This thesis examines the effects of varying loads and repetitions on caloric expenditure during back squats. Fifteen subjects performed four different 4-minute squat protocols using loads of 5kg, 10kg, 15kg, or 20kg at contraction speeds of 1, 2, 3, or 4 seconds respectively, to maintain the same total work. Heart rate and physical activity energy expenditure were measured. Results showed that mean heart rate and caloric expenditure decreased as load increased from 5kg to 20kg. The 5kg protocol elicited the highest caloric expenditure, suggesting that a high-repetition, low-load protocol maximizes energy use during back squats in a short time period.
Training Load and Fatigue Marker Associations with Injury and IllnessFernando Farias
This paper provides a comprehensive review of the litera-
ture that has reported the monitoring of longitudinal
training load and fatigue and its relationship with injury
and illness. The current findings highlight disparity in the
terms used to define training load, fatigue, injury and ill-
ness, as well as a lack of investigation of fatigue and
training load interactions. Key stages of training and
competition where the athlete is at an increased risk of
injury/illness risk were identified. These included periods
of training load intensification, accumulation of training
load and acute change in load. Modifying training load
during these periods may help reduce the potential for
injury and illness.
A evidência apresentada sugere que a variação é um componente necessário do planejamento efetivo do treinamento. Apoiando essa perspectiva, outras pesquisas sugerem que a monotonia de treinamento elevado - que pode ser amplamente percebida como uma falta de variação20 - leva a uma maior incidência de síndromes de overtraining21, um mau desempenho e freqüência de infecções banais.22 Inversamente, as reduções na monotonia têm Tem sido associada a uma maior incidência de melhor desempenho pessoal 22, e os índices de monotonia têm sido defendidos como ferramentas benéficas de treinamento-regulação na elite rowing23 e no sprint24.
1) A study investigated the effects of 22 weeks of periodized soccer training focused on technical-tactical ability in young players.
2) The training reduced markers of muscle damage (CK and LDH levels) over time and improved high-intensity performance and tactical metrics in games.
3) Players who saw greater reductions in muscle damage markers also had larger increases in high-intensity actions during games.
Acute cardiopulmonary and metabolic responses to high intensity interval trai...Fernando Farias
Results from the present study quantify the effects of altering either the intensity of the
work or the recovery interval when performing interval sessions consisting of 60s of work and
60s of recovery for multiple repetitions. The information provided may aid those interested in
designing interval training sessions by providing ranges of values that could be expected for
individuals who possess moderate levels of cardiopulmonary fitness. Using a work intensity of
80% or 100% VGO2peak and a recovery intensity of 0% or 50% VGO2peak, subjects were able to
exercise within the ACSM recommended range for exercise intensity. Based upon the data it
would appear that a protocol such as the 80/0 may be appropriate for those individuals who
are just beginning a program or have little experience with interval-type activity. By contrast, a
100/50 protocol could not be completed by all of the subjects and therefore may be too intense
for some individuals.
Effects of Velocity Loss During Resistance Training on Performance in Profess...Fernando Farias
To analyze the effects of two resistance training (RT) programs that used the same relative loading but different repetition volume, using the velocity loss during the set as the independent variable: 15% (VL15) vs. 30% (VL30). Methods: Sixteen professional soccer players with RT experience (age 23.8 ± 3.5 years, body mass 75.5 ± 8.6 kg) were randomly assigned to two groups: VL15 (n = 8) or VL30 (n = 8) that followed a 6-week (18 sessions) velocity-based squat training program. Repetition velocity was monitored in all sessions. Assessments performed before (Pre) and after training (Post) included: estimated one- repetition maximum (1RM) and change in average mean propulsive velocity (AMPV) against absolute loads common to Pre and Post tests; countermovement jump (CMJ); 30-m sprint (T30); and Yo-yo intermittent recovery test (YYIRT).
Short inter-set rest blunts resistance exercise-inducedFernando Farias
Manipulating the rest-recovery interval between sets of resistance exercise may influence
training-induced muscle remodelling. The aim of this study was to determine the acute muscle
anabolic response to resistance exercise performed with short or long inter-set rest intervals.
In a study with a parallel-group design, 16 males completed four sets of bilateral leg-press and
knee-extension exercise at 75% of one-repetition maximum to momentary muscular failure,
followed by ingestion of 25 g of whey protein. Resistance exercise sets were interspersed by
1 min (n = 8) or 5 min of passive rest (n = 8). Muscle biopsies were obtained at rest, 0, 4, 24
and 28 h postexercise during a primed continuous infusion of l-[ring-13C6]phenylalanine to
determine myofibrillar protein synthesis and intracellular signalling.
Eccentric training can improve muscle strength, power, and stretch-shortening cycle function to a greater extent than concentric or traditional resistance training. While both eccentric and concentric training increase muscle strength, the increases tend to be mode-specific. Eccentric training with loads greater than concentric strength limits elicits greater overall strength gains. Faster contraction velocities during eccentric training may further enhance strength and power adaptations. Eccentric training appears especially effective for improving performance requiring stretch-shortening cycle function.
Cold water immersion versus whole body cryotherapyFernando Farias
Cold-water immersion was more effective in
accelerating recovery kinetics than whole-body cryotherapy for countermovement jump
performance at 72h post-exercise. Cold-water immersion also demonstrated lower soreness
and higher perceived recovery levels across 24-48h post-exercise.
Training Load and Fatigue Marker Associations with Injury and IllnessFernando Farias
This paper provides a comprehensive review of the litera-
ture that has reported the monitoring of longitudinal
training load and fatigue and its relationship with injury
and illness. The current findings highlight disparity in the
terms used to define training load, fatigue, injury and ill-
ness, as well as a lack of investigation of fatigue and
training load interactions. Key stages of training and
competition where the athlete is at an increased risk of
injury/illness risk were identified. These included periods
of training load intensification, accumulation of training
load and acute change in load. Modifying training load
during these periods may help reduce the potential for
injury and illness.
A evidência apresentada sugere que a variação é um componente necessário do planejamento efetivo do treinamento. Apoiando essa perspectiva, outras pesquisas sugerem que a monotonia de treinamento elevado - que pode ser amplamente percebida como uma falta de variação20 - leva a uma maior incidência de síndromes de overtraining21, um mau desempenho e freqüência de infecções banais.22 Inversamente, as reduções na monotonia têm Tem sido associada a uma maior incidência de melhor desempenho pessoal 22, e os índices de monotonia têm sido defendidos como ferramentas benéficas de treinamento-regulação na elite rowing23 e no sprint24.
1) A study investigated the effects of 22 weeks of periodized soccer training focused on technical-tactical ability in young players.
2) The training reduced markers of muscle damage (CK and LDH levels) over time and improved high-intensity performance and tactical metrics in games.
3) Players who saw greater reductions in muscle damage markers also had larger increases in high-intensity actions during games.
Acute cardiopulmonary and metabolic responses to high intensity interval trai...Fernando Farias
Results from the present study quantify the effects of altering either the intensity of the
work or the recovery interval when performing interval sessions consisting of 60s of work and
60s of recovery for multiple repetitions. The information provided may aid those interested in
designing interval training sessions by providing ranges of values that could be expected for
individuals who possess moderate levels of cardiopulmonary fitness. Using a work intensity of
80% or 100% VGO2peak and a recovery intensity of 0% or 50% VGO2peak, subjects were able to
exercise within the ACSM recommended range for exercise intensity. Based upon the data it
would appear that a protocol such as the 80/0 may be appropriate for those individuals who
are just beginning a program or have little experience with interval-type activity. By contrast, a
100/50 protocol could not be completed by all of the subjects and therefore may be too intense
for some individuals.
Effects of Velocity Loss During Resistance Training on Performance in Profess...Fernando Farias
To analyze the effects of two resistance training (RT) programs that used the same relative loading but different repetition volume, using the velocity loss during the set as the independent variable: 15% (VL15) vs. 30% (VL30). Methods: Sixteen professional soccer players with RT experience (age 23.8 ± 3.5 years, body mass 75.5 ± 8.6 kg) were randomly assigned to two groups: VL15 (n = 8) or VL30 (n = 8) that followed a 6-week (18 sessions) velocity-based squat training program. Repetition velocity was monitored in all sessions. Assessments performed before (Pre) and after training (Post) included: estimated one- repetition maximum (1RM) and change in average mean propulsive velocity (AMPV) against absolute loads common to Pre and Post tests; countermovement jump (CMJ); 30-m sprint (T30); and Yo-yo intermittent recovery test (YYIRT).
Short inter-set rest blunts resistance exercise-inducedFernando Farias
Manipulating the rest-recovery interval between sets of resistance exercise may influence
training-induced muscle remodelling. The aim of this study was to determine the acute muscle
anabolic response to resistance exercise performed with short or long inter-set rest intervals.
In a study with a parallel-group design, 16 males completed four sets of bilateral leg-press and
knee-extension exercise at 75% of one-repetition maximum to momentary muscular failure,
followed by ingestion of 25 g of whey protein. Resistance exercise sets were interspersed by
1 min (n = 8) or 5 min of passive rest (n = 8). Muscle biopsies were obtained at rest, 0, 4, 24
and 28 h postexercise during a primed continuous infusion of l-[ring-13C6]phenylalanine to
determine myofibrillar protein synthesis and intracellular signalling.
Eccentric training can improve muscle strength, power, and stretch-shortening cycle function to a greater extent than concentric or traditional resistance training. While both eccentric and concentric training increase muscle strength, the increases tend to be mode-specific. Eccentric training with loads greater than concentric strength limits elicits greater overall strength gains. Faster contraction velocities during eccentric training may further enhance strength and power adaptations. Eccentric training appears especially effective for improving performance requiring stretch-shortening cycle function.
Cold water immersion versus whole body cryotherapyFernando Farias
Cold-water immersion was more effective in
accelerating recovery kinetics than whole-body cryotherapy for countermovement jump
performance at 72h post-exercise. Cold-water immersion also demonstrated lower soreness
and higher perceived recovery levels across 24-48h post-exercise.
Melhorar ou até mesmo manter o desempenho atlético em jogadores de esportes de equipe competitivos durante o longo período da temporada é um dos maiores desafios para qualquer treinador comprometido. Tempo muito limitado está disponível entre as partidas semanais para introduzir sessões intensivas de treinamento de força e poder, com uma freqüência normal de 1-2 unidades por semana. Este fato estimula a busca de métodos de treinamento mais eficientes capazes de melhorar uma ampla variedade de habilidades funcionais, evitando ao mesmo tempo os efeitos de fadiga.
Comparison of anticipation time of judokas, Wrestlers and BoxersSports Journal
Objective of the study was to see if there is any significant difference exists between the judokas, wrestlers and boxers on anticipation time by comparing their anticipation time performances. To test the hypothesis that the three groups have non-significant differences on anticipation time variables namely number of early and late responses and also average time deviation from early and late responses, 96 male only sportspersons having mean age 22.49 ± 2.37 were being randomly tested who had at least participated at state level in their respective sport. Each sports person was given three trials of 20 responses and the average value of all the three trials was recorded on Basin anticipation timer (B.A.T.) machine. One way MANOVA using SPSS 23 statistical package was applied to get and analyze the results. There was a statistically non-significant difference in 4 anticipation time variables based on the sport which they practice, F (8, 180) = .651, p > .05; Wilk's Λ = 0.945, partial η2 = .028. The null hypothesis that there would be no significant difference between the three groups was therefore accepted and alternate hypothesis was rejected.
The hamstring muscle group is the most frequently injured, representing
approximately 12 to 24% of all athletic injuries.1,2 These injuries may be due to
disproportionate training performed for the quadriceps,3 with hamstring strains
occurring more frequently in those who demonstrated hamstring weakness, and
lower hamstring-to-quadriceps strength ratios.2 Thus, hamstring strength is impor-
tant for athletic performance and injury prevention in a variety of sports.
Comparative Study on Selected Strength between Non Sports Performer and Sport...iosrjce
purpose of the present study was to compare the strength between sports perform students and non
sports perform students of Jamboni block. The present studies, twenty-five(25) sports perform college student
were selected throw purposive sampling process from the Seva Bharati Mahavidyalaya (SBM) boys hostel
.Other twenty-five(25) college student fifteen randomly selected from dept. of commerce & science of Seva
Bharati Mahavidyalaya, which established at Jamboni block in Paschim Medinipur district in West Bengal
state. Age range of selected subjects in present studies were in between 19 to 23 year. The selected strength
were evaluated in the present study throw sit-up>abdominal strength, pull-up> arm/shoulder strength, standing
broad jump>leg explosive power, selected variables were tested according to “AAPHER youth test Battery”
and “t” test used to test the hypothesis.
Changes During Passive Recovery In Lower Limbs Tiredness After Strenuous WorkoutIOSR Journals
Abstract: Lower limbs tiredness is a widely accepted indicator for recovery state prediction. The study was
designed and purposed to know the rate and trend of lower limbs tiredness recovery after strenuous workout in
passive state. Ten athletes from LNIPE, Gwalior having almost similar anthropometric measurements,
physiological capacity, chronological age(18-19 year), training age(5-6 year), event(sprinters) etc. residing in
same campus having similar daily routine were selected as participant in this experiment. The experiment was
conducted in a highly controlled environment using sophisticate equipments. Target Heart Rate Zone of the
workout lasting for 20 minutes was 80%-90% of their Maximum Heart Rate. Three readings including pre, post
and 30 minutes post workout was considered for both the two tests (Isometric Leg Strength Test and Sergeant
Jump Test) selected for the purpose. rANOVA was employed separately to derive out meaningful information
from the raw data. In both the tests well controlled workout for 20 minutes resulted in significant increase state
of post workout readings. With passage of time after 30 minutes post passive recovery there was no
improvement in state of tiredness. Thus scope of future research is there in planning out means and methods to
promote lower limbs tiredness recovery during this post recovery period.
Keyword: Isometric Leg Strength Test, Sergeant Jump Test, Recovery, rANOVA
Muscle activation during various hamstring exercisesFernando Farias
The main findings of this investigation demonstrate that
there are significant differences in activation within muscles
when comparing all exercises. Although one might expect
similar activation for a given muscle for activities of similar
kinematics, such as the prone leg curl and glute-ham raise,
this is not the case with the data herein
The work evaluates the response of the heart rate of non-mechanics handling some specific loads in the common postures employed during road-side repair of automobile and later, the result was validated with the auto-mechanics during repair activities. The purpose is to specify the safe work-impulse of auto-mechanics in the common postures, such as, bending, stooping and supine posture, used during roadside repair. The safe work-impulse was determined for preselected healthy non-mechanics of the classified age groups who gave informed consent. Increase in heart rates at exhaustion of non-mechanics in each age group, in lifting predetermined loads were measured using digital premium pressure monitor with a comfit cuff. Consequently, the work-impulse charts for the load classifications and different age-groups were developed for the different postures. The heart rates of the auto-mechanics performing specific tasks during engine repairs were then measured to determine the equivalent work-impulse, using the developed charts. The result revealed that, auto-mechanics handling the same mass of load under the same conditions have lower safe work-impulse. In conclusion, the study reveals that roadside auto-mechanics have the capacity to sustain higher safe work-impulse in bending and supine postures than in stooping posture.
The purpose of this investigation is comparing the effects of three admitting models using maximum admits in increasing the maximum strength and hypertrophy of unexercised men in the muscles of arm forth. Statistical sample of this investigation are 45 non-athlete male students of Mazandaran University of Science and Technology of the Department of Public Physical Education. Maximum strength and the mass of muscles in the sample was measured using the maximum repeating test in moving arm form by Haler or measured using the arm, before and after the match. Then, the samples were grouped in 3 empirical groups (15 per groups). They exercised for 8 weeks, 3 sessions per week, and 75 minutes per session. The data were analyzed by variance and (LSD) by using SPSS20 software (p≤0.05). There was no meaningful difference among 3 models; normally pyramidal, Counter-pyramidal, and Flat-pyramidal in increasing the shape of arm forth. Also, there was a meaningful difference between two methods, pyramids and flat pyramid after the test. There was no meaningful difference among the methods between counter-pyramidal and flat-pyramidal. So, we can suggest that when the purpose is increasing the muscle, we can use every method, but if the purpose is increasing the strength, it is preferring to use flat pyramidal method.
The document summarizes a study that examined the effects of endurance, resistance, and concurrent (endurance and resistance) training on cardiac structure in female students. The study found that 8 weeks of concurrent training significantly increased left ventricular end diastolic diameter compared to endurance or resistance training alone. Concurrent training also significantly increased left ventricular end systolic diameter, mass, and mass index. No other measured variables showed significant differences between groups. The results indicate that concurrent training may have a greater impact on cardiac adaptations than single-mode endurance or resistance training.
EFFECTS OF STRENGTH TRAINING ON SQUAT AND SPRINT PERFORMANCE IN SOCCER PLAYERSFernando Farias
We have demonstrated that a simple in-season strength training program resulted in an improvement in maximal back squat performance, which was reflected in improve- ments in short sprint performance, as identified by a decrease in sprint time over 5, 10, and 20 m, in professional soccer players, in line with the hypotheses. Furthermore, the changes in relative 1RM squat strength demonstrate strong associations with the changes in 5 (r = 0.62), 10 (r = 0.78), and 20-m (r = 0.60) sprint performances.
Training the vertical jump to head the ball in soccer Fernando Farias
IN MODERN SOCCER, HEADING
THE BALL IS BOTH AN OFFENSIVE
TOOL USED TO SCORE GOALS
AND A DEFENSIVE MEASURE
AGAINST OPPOSING TEAMS. PRO-
FICIENCY IN HEADING THE BALL
REQUIRES PROPER TECHNIQUE IN
CONJUNCTION WITH AN EFFEC-
TIVE VERTICAL JUMP. THE AIM OF
THIS ARTICLE IS TO ADDRESS THE
FACTORS INVOLVED IN VERTICAL
JUMP PERFORMANCE AND HOW
THEY RELATE SPECIFICALLY TO
HEADING THE BALL
Sprint running acceleration is a key feature of physical performance in team sports, and recent
literature shows that the ability to generate large magnitudes of horizontal ground reaction force
and mechanical effectiveness of force application are paramount. We tested the hypothesis that
very-heavy loaded sled sprint training would induce an improvement in horizontal force
production, via an increased effectiveness of application. Training-induced changes in sprint
performance and mechanical outputs were computed using a field method based on velocity-
time data, before and after an 8-week protocol (16 sessions of 10x20-m sprints). 16 male
amateur soccer players were assigned to either a very-heavy sled (80% body-mass sled load)
or a control group (unresisted sprints). The main outcome of this pilot study is that very-heavy
sled resisted sprint training, using much greater loads than traditionally recommended, clearly
increased maximal horizontal force production compared to standard unloaded sprint training
(effect size of 0.80 vs 0.20 for controls, unclear between-group difference) and mechanical
effectiveness (i.e. more horizontally applied force; effect size of 0.95 vs -0.11, moderate
between-group difference)
The use of stretching in the training programs of recrea-
tional and competitive athletes has been historically common-
place. The role of stretching in enhancing athletic performance
has been debated (49). The purpose of this review was to
examine the literature regarding the effect of stretching on
performance, without regard to any of the other purported
effects of stretching, including improvements in joint range
of motion, muscle length, or recovery from or susceptibility
to injury.
F
oam rollers and massage sticks have increased in popularity
in the fitness industry and are often recommended by
strength and conditioning professionals (5,6,10). There is
evidence that shows positive effects of foam rolling on range of
motion (ROM), recovery, and performance (8,9,10,14). Despite its
effectiveness, the mechanisms as to how foam rolling works are
not fully understood. However, it is likely that acute responses in
foam rolling are similar to those elicited by manual therapy, which
are thought to be neurophysiological in origin .
The effect of instability training on knee joint proprioception and core stre...Fernando Farias
A general 10-week IT program utilizing Swiss balls and body mass as a resistance proved effective for improving knee proprioception as well as trunk flexion and extension strength in previously inactive individuals. The present study demonstrates that the use of body weight as a resis- tance under unstable conditions can provide significant improvements in knee proprioception (for as long as 9 months after training) and trunk strength for the untrained population that should contribute to general health and functionality.
Os resultados atuais indicaram que a ocorrência de lesões de isquiotibiais podem estar associadas a uma mudança hierárquica na distribuição da atividade metabólica dentro do complexo muscular do isquiotibial após o trabalho excêntrico em que o Semitendinoso provavelmente deveria tomar a parte principal, seguido pelo BÍceps Femural e Semimembranoso. Quando o BF aumenta sua contribuição e é ativado em uma extensão proporcionalmente maior, o risco de sofrer uma lesão do isquiotibial pode aumentar substancialmente.
This document provides an analysis of an athlete's needs for wrestling. It summarizes the athlete's profile, including that he is a 28-year-old male wrestler weighing 71kg who competes in Greco-Roman and freestyle wrestling. It analyzes the physiological and biomechanical demands of wrestling, including the predominant muscle groups used and energy systems relied upon. It also evaluates the athlete's current strength, power, speed, flexibility and injury risk to identify areas for improvement in his training to better meet the physical demands of wrestling.
A strong relationship exists between good health and the ability to perform daily activities vigorously while being associated with a low risk of prematurely developing hypokinetic diseases. Health-related fitness testing provides essential data to educate participants on their fitness status, develop appropriate exercise prescriptions, and establish motivational and attainable fitness goals while stratifying cardiovascular risk. Proper screening and testing procedures should be followed to safely assess factors like cardiorespiratory fitness, muscular strength and endurance, flexibility, and body composition.
The document discusses positive behavior support systems for non-classroom settings in schools. It emphasizes active supervision by staff, teaching and encouraging positive expectations and routines, precorrecting to remind students of rules, and providing positive reinforcement. Key components of non-classroom setting systems include staff having more positive than negative interactions with students, students being able to describe expectations, and implementing features like school-wide implementation and data-based decision making.
Melhorar ou até mesmo manter o desempenho atlético em jogadores de esportes de equipe competitivos durante o longo período da temporada é um dos maiores desafios para qualquer treinador comprometido. Tempo muito limitado está disponível entre as partidas semanais para introduzir sessões intensivas de treinamento de força e poder, com uma freqüência normal de 1-2 unidades por semana. Este fato estimula a busca de métodos de treinamento mais eficientes capazes de melhorar uma ampla variedade de habilidades funcionais, evitando ao mesmo tempo os efeitos de fadiga.
Comparison of anticipation time of judokas, Wrestlers and BoxersSports Journal
Objective of the study was to see if there is any significant difference exists between the judokas, wrestlers and boxers on anticipation time by comparing their anticipation time performances. To test the hypothesis that the three groups have non-significant differences on anticipation time variables namely number of early and late responses and also average time deviation from early and late responses, 96 male only sportspersons having mean age 22.49 ± 2.37 were being randomly tested who had at least participated at state level in their respective sport. Each sports person was given three trials of 20 responses and the average value of all the three trials was recorded on Basin anticipation timer (B.A.T.) machine. One way MANOVA using SPSS 23 statistical package was applied to get and analyze the results. There was a statistically non-significant difference in 4 anticipation time variables based on the sport which they practice, F (8, 180) = .651, p > .05; Wilk's Λ = 0.945, partial η2 = .028. The null hypothesis that there would be no significant difference between the three groups was therefore accepted and alternate hypothesis was rejected.
The hamstring muscle group is the most frequently injured, representing
approximately 12 to 24% of all athletic injuries.1,2 These injuries may be due to
disproportionate training performed for the quadriceps,3 with hamstring strains
occurring more frequently in those who demonstrated hamstring weakness, and
lower hamstring-to-quadriceps strength ratios.2 Thus, hamstring strength is impor-
tant for athletic performance and injury prevention in a variety of sports.
Comparative Study on Selected Strength between Non Sports Performer and Sport...iosrjce
purpose of the present study was to compare the strength between sports perform students and non
sports perform students of Jamboni block. The present studies, twenty-five(25) sports perform college student
were selected throw purposive sampling process from the Seva Bharati Mahavidyalaya (SBM) boys hostel
.Other twenty-five(25) college student fifteen randomly selected from dept. of commerce & science of Seva
Bharati Mahavidyalaya, which established at Jamboni block in Paschim Medinipur district in West Bengal
state. Age range of selected subjects in present studies were in between 19 to 23 year. The selected strength
were evaluated in the present study throw sit-up>abdominal strength, pull-up> arm/shoulder strength, standing
broad jump>leg explosive power, selected variables were tested according to “AAPHER youth test Battery”
and “t” test used to test the hypothesis.
Changes During Passive Recovery In Lower Limbs Tiredness After Strenuous WorkoutIOSR Journals
Abstract: Lower limbs tiredness is a widely accepted indicator for recovery state prediction. The study was
designed and purposed to know the rate and trend of lower limbs tiredness recovery after strenuous workout in
passive state. Ten athletes from LNIPE, Gwalior having almost similar anthropometric measurements,
physiological capacity, chronological age(18-19 year), training age(5-6 year), event(sprinters) etc. residing in
same campus having similar daily routine were selected as participant in this experiment. The experiment was
conducted in a highly controlled environment using sophisticate equipments. Target Heart Rate Zone of the
workout lasting for 20 minutes was 80%-90% of their Maximum Heart Rate. Three readings including pre, post
and 30 minutes post workout was considered for both the two tests (Isometric Leg Strength Test and Sergeant
Jump Test) selected for the purpose. rANOVA was employed separately to derive out meaningful information
from the raw data. In both the tests well controlled workout for 20 minutes resulted in significant increase state
of post workout readings. With passage of time after 30 minutes post passive recovery there was no
improvement in state of tiredness. Thus scope of future research is there in planning out means and methods to
promote lower limbs tiredness recovery during this post recovery period.
Keyword: Isometric Leg Strength Test, Sergeant Jump Test, Recovery, rANOVA
Muscle activation during various hamstring exercisesFernando Farias
The main findings of this investigation demonstrate that
there are significant differences in activation within muscles
when comparing all exercises. Although one might expect
similar activation for a given muscle for activities of similar
kinematics, such as the prone leg curl and glute-ham raise,
this is not the case with the data herein
The work evaluates the response of the heart rate of non-mechanics handling some specific loads in the common postures employed during road-side repair of automobile and later, the result was validated with the auto-mechanics during repair activities. The purpose is to specify the safe work-impulse of auto-mechanics in the common postures, such as, bending, stooping and supine posture, used during roadside repair. The safe work-impulse was determined for preselected healthy non-mechanics of the classified age groups who gave informed consent. Increase in heart rates at exhaustion of non-mechanics in each age group, in lifting predetermined loads were measured using digital premium pressure monitor with a comfit cuff. Consequently, the work-impulse charts for the load classifications and different age-groups were developed for the different postures. The heart rates of the auto-mechanics performing specific tasks during engine repairs were then measured to determine the equivalent work-impulse, using the developed charts. The result revealed that, auto-mechanics handling the same mass of load under the same conditions have lower safe work-impulse. In conclusion, the study reveals that roadside auto-mechanics have the capacity to sustain higher safe work-impulse in bending and supine postures than in stooping posture.
The purpose of this investigation is comparing the effects of three admitting models using maximum admits in increasing the maximum strength and hypertrophy of unexercised men in the muscles of arm forth. Statistical sample of this investigation are 45 non-athlete male students of Mazandaran University of Science and Technology of the Department of Public Physical Education. Maximum strength and the mass of muscles in the sample was measured using the maximum repeating test in moving arm form by Haler or measured using the arm, before and after the match. Then, the samples were grouped in 3 empirical groups (15 per groups). They exercised for 8 weeks, 3 sessions per week, and 75 minutes per session. The data were analyzed by variance and (LSD) by using SPSS20 software (p≤0.05). There was no meaningful difference among 3 models; normally pyramidal, Counter-pyramidal, and Flat-pyramidal in increasing the shape of arm forth. Also, there was a meaningful difference between two methods, pyramids and flat pyramid after the test. There was no meaningful difference among the methods between counter-pyramidal and flat-pyramidal. So, we can suggest that when the purpose is increasing the muscle, we can use every method, but if the purpose is increasing the strength, it is preferring to use flat pyramidal method.
The document summarizes a study that examined the effects of endurance, resistance, and concurrent (endurance and resistance) training on cardiac structure in female students. The study found that 8 weeks of concurrent training significantly increased left ventricular end diastolic diameter compared to endurance or resistance training alone. Concurrent training also significantly increased left ventricular end systolic diameter, mass, and mass index. No other measured variables showed significant differences between groups. The results indicate that concurrent training may have a greater impact on cardiac adaptations than single-mode endurance or resistance training.
EFFECTS OF STRENGTH TRAINING ON SQUAT AND SPRINT PERFORMANCE IN SOCCER PLAYERSFernando Farias
We have demonstrated that a simple in-season strength training program resulted in an improvement in maximal back squat performance, which was reflected in improve- ments in short sprint performance, as identified by a decrease in sprint time over 5, 10, and 20 m, in professional soccer players, in line with the hypotheses. Furthermore, the changes in relative 1RM squat strength demonstrate strong associations with the changes in 5 (r = 0.62), 10 (r = 0.78), and 20-m (r = 0.60) sprint performances.
Training the vertical jump to head the ball in soccer Fernando Farias
IN MODERN SOCCER, HEADING
THE BALL IS BOTH AN OFFENSIVE
TOOL USED TO SCORE GOALS
AND A DEFENSIVE MEASURE
AGAINST OPPOSING TEAMS. PRO-
FICIENCY IN HEADING THE BALL
REQUIRES PROPER TECHNIQUE IN
CONJUNCTION WITH AN EFFEC-
TIVE VERTICAL JUMP. THE AIM OF
THIS ARTICLE IS TO ADDRESS THE
FACTORS INVOLVED IN VERTICAL
JUMP PERFORMANCE AND HOW
THEY RELATE SPECIFICALLY TO
HEADING THE BALL
Sprint running acceleration is a key feature of physical performance in team sports, and recent
literature shows that the ability to generate large magnitudes of horizontal ground reaction force
and mechanical effectiveness of force application are paramount. We tested the hypothesis that
very-heavy loaded sled sprint training would induce an improvement in horizontal force
production, via an increased effectiveness of application. Training-induced changes in sprint
performance and mechanical outputs were computed using a field method based on velocity-
time data, before and after an 8-week protocol (16 sessions of 10x20-m sprints). 16 male
amateur soccer players were assigned to either a very-heavy sled (80% body-mass sled load)
or a control group (unresisted sprints). The main outcome of this pilot study is that very-heavy
sled resisted sprint training, using much greater loads than traditionally recommended, clearly
increased maximal horizontal force production compared to standard unloaded sprint training
(effect size of 0.80 vs 0.20 for controls, unclear between-group difference) and mechanical
effectiveness (i.e. more horizontally applied force; effect size of 0.95 vs -0.11, moderate
between-group difference)
The use of stretching in the training programs of recrea-
tional and competitive athletes has been historically common-
place. The role of stretching in enhancing athletic performance
has been debated (49). The purpose of this review was to
examine the literature regarding the effect of stretching on
performance, without regard to any of the other purported
effects of stretching, including improvements in joint range
of motion, muscle length, or recovery from or susceptibility
to injury.
F
oam rollers and massage sticks have increased in popularity
in the fitness industry and are often recommended by
strength and conditioning professionals (5,6,10). There is
evidence that shows positive effects of foam rolling on range of
motion (ROM), recovery, and performance (8,9,10,14). Despite its
effectiveness, the mechanisms as to how foam rolling works are
not fully understood. However, it is likely that acute responses in
foam rolling are similar to those elicited by manual therapy, which
are thought to be neurophysiological in origin .
The effect of instability training on knee joint proprioception and core stre...Fernando Farias
A general 10-week IT program utilizing Swiss balls and body mass as a resistance proved effective for improving knee proprioception as well as trunk flexion and extension strength in previously inactive individuals. The present study demonstrates that the use of body weight as a resis- tance under unstable conditions can provide significant improvements in knee proprioception (for as long as 9 months after training) and trunk strength for the untrained population that should contribute to general health and functionality.
Os resultados atuais indicaram que a ocorrência de lesões de isquiotibiais podem estar associadas a uma mudança hierárquica na distribuição da atividade metabólica dentro do complexo muscular do isquiotibial após o trabalho excêntrico em que o Semitendinoso provavelmente deveria tomar a parte principal, seguido pelo BÍceps Femural e Semimembranoso. Quando o BF aumenta sua contribuição e é ativado em uma extensão proporcionalmente maior, o risco de sofrer uma lesão do isquiotibial pode aumentar substancialmente.
This document provides an analysis of an athlete's needs for wrestling. It summarizes the athlete's profile, including that he is a 28-year-old male wrestler weighing 71kg who competes in Greco-Roman and freestyle wrestling. It analyzes the physiological and biomechanical demands of wrestling, including the predominant muscle groups used and energy systems relied upon. It also evaluates the athlete's current strength, power, speed, flexibility and injury risk to identify areas for improvement in his training to better meet the physical demands of wrestling.
A strong relationship exists between good health and the ability to perform daily activities vigorously while being associated with a low risk of prematurely developing hypokinetic diseases. Health-related fitness testing provides essential data to educate participants on their fitness status, develop appropriate exercise prescriptions, and establish motivational and attainable fitness goals while stratifying cardiovascular risk. Proper screening and testing procedures should be followed to safely assess factors like cardiorespiratory fitness, muscular strength and endurance, flexibility, and body composition.
The document discusses positive behavior support systems for non-classroom settings in schools. It emphasizes active supervision by staff, teaching and encouraging positive expectations and routines, precorrecting to remind students of rules, and providing positive reinforcement. Key components of non-classroom setting systems include staff having more positive than negative interactions with students, students being able to describe expectations, and implementing features like school-wide implementation and data-based decision making.
O documento discute as necessidades humanas básicas de comida e bebida, mas também o desejo por diversão, arte, amor e felicidade. Reforça que as pessoas não querem apenas o básico para sobreviver, mas sim uma vida plena que traz prazer e realização.
Dr.Szirmay Rókus / textile industry developing /szirmay-design
This document discusses textile developments for military, sports, and lifesaving clothing. It describes standards like AQAP and SOLAS that relate to quality assurance and maritime safety. It also lists various sewing tools, techniques, materials, and types of clothing produced like protective coats, uniforms, and sportswear. Experiments are described that test properties like thermal resistance, moisture resistance, strength, and durability of the materials.
Este documento proporciona instrucciones en 10 pasos para registrarse y agregar canales RSS a Netvibes. Los pasos incluyen ingresar un correo electrónico y contraseña para registrarse, hacer clic en "Agregar contenido" y "Agregar un feed", ingresar la URL del sitio web, y hacer clic en "Agregar feed" para añadir con éxito el canal RSS a la cuenta de Netvibes.
Joe Doherty has over 18 years of experience as an Industrial Hygiene, Occupational Safety, Health and Environmental Manager and Supervisor. He served for 18.5 years in the US Navy as a Safety and Health Specialist. He is skilled in managing safety programs, conducting inspections, investigations, training, and ensuring regulatory compliance. He has extensive experience developing and implementing safety programs, procedures, and training for facilities, shipyards, and vessels.
PREDICTORS OF A PROPOSED COMBAT READINESS TESTJA Larson
The document summarizes a dissertation that examined the relationship between performance on the proposed U.S. Army Combat Readiness Test (ACRT) and various measures of physical fitness. Forty-three male subjects participated in field and laboratory testing sessions. In the field, subjects completed the proposed ACRT, which includes events like sprinting, obstacle courses, and casualty drags. In the lab, subjects underwent assessments of muscular strength and endurance, postural stability, aerobic capacity, anaerobic capacity, flexibility, body composition, fat-free mass, and agility. Regression analysis identified that muscular endurance, aerobic capacity, body composition, fat-free mass, and agility contributed to a model that
This document discusses core stability, core strength, and their relationship to athletic performance. It begins by defining key terms like performance, core stability, and core strength. It then explores the functional anatomy of the core and different types of core training. The document reviews evidence that core training provides benefits in rehabilitation by reducing lower back injuries, but evidence of performance enhancement in sports is less clear. Specifically, some studies found improvements in core stability and strength from training but ambiguous results on actual sports performance. The relationship between core stability, functional movement, and different performance tests is also examined but results suggest only weak to moderate correlations. While core and functional training are important for injury prevention, the evidence does not strongly support them as the primary focus for performance
This document provides a literature review on the effects of tart cherry supplementation on muscle damage and recovery. It discusses how muscle damage can occur through mechanical or metabolic mechanisms and causes delayed onset muscle soreness (DOMS). Tart cherries contain antioxidants and anti-inflammatories that may reduce muscle damage and inflammation. Previous research found tart cherry supplementation improved recovery following exercise in trained individuals, but no studies have examined untrained people. This study aims to investigate if tart cherry supplementation can reduce muscle soreness, accelerate force regeneration, and lower creatine kinase levels in untrained people after muscle-damaging exercise.
EFFECTS OF REST INTERVALS ON NEUROMUSCULAR ACTIVITY i EvonCanales257
EFFECTS OF REST INTERVALS ON NEUROMUSCULAR ACTIVITY i
Running head: EFFECTS OF REST INTERVALS ON NEUROMUSCULAR ACTIVITY
Thesis
Submitted to the School of Health and Human Performance at Kean University in Partial
Fulfillment of the Requirement of the Degree of Master’s of Science in Exercise Science
Richard Osolinski
Advisor: Dr. Walter Andzel
Dr. Timothy Marshall
Kean University
Union, NJ
March, 2019
Faculty Advisor___________________________________Date_______________
Faculty Advisor___________________________________Date_______________
EFFECTS OF REST INTERVALS ON NEUROMUSCULAR ACTIVITY ii
Table of Content
Appendices ....................................................................................................................................iii
List of Tables ................................................................................................................................ iv
Acknowledgements..........................................................................................................................v
Abstract...........................................................................................................................................vi
1. Introduction...............……………………………………………………......….......................1
Hypotheses.………….....………………………………........................….............................10
Limitations...……………......…………………………………………..................................11
Delimitations....……………....…………………………………………................................11
Operational Definitions........................……….....…………………………………...……....12
2. Review of the Literature..........................…………………………………………………....13
Biological Mechanisms.......…...……………………………………………….....................13
Effects of Resistance Training.………………………………………………........................15
Manipulation of Loads..... …………......…………………………………….........................19
Manipulation of Pair Training...........………………………………………..........................22
Manipulation of Sets/Volume .................……………………………………........................24
Manipulation of Training Frequency………………………………………...........................26
Manipulation of Rest Intervals................................................................................................29
Summary of the Review of Literature.…...……………………………….............................29
3. Methods..............……………………………………………………………..........................34
Participants…………………………………………………………….………......................34
Instrumentation.……………………………………………………………...........................34
Procedures…………………………………………………………………............................35
Testing Procedures.………………………………………………………..............................36
Statistical Analysis.…………………………………………………………..........................37
4. Results…………...………………………………………………...................... ...
American Thoracic Society American College Of Chest Physicians ATS ACCP Stat...Justin Knight
This document provides guidelines for cardiopulmonary exercise testing (CPET) based on expert consensus. CPET provides a global assessment of how the body functions during exercise by evaluating multiple organ systems together. It is increasingly being used clinically to evaluate unexplained exercise intolerance, functional capacity, and impairment. The document covers indications for CPET, methodology, measurements and interpretations, reference values, and patterns of abnormal exercise responses in various diseases. The intended audience is those performing and using CPET to assist clinical decision making.
This study evaluated a new method of monitoring exercise training called the session rating of perceived exertion (RPE) method. The session RPE method uses a participant's perceived exertion after a training session as a marker of training intensity. The study compared the session RPE method to an objective heart rate (HR) monitoring method during steady state and interval cycling, as well as basketball practice. It found a consistent relationship between the two monitoring methods, though the session RPE scores were generally higher. Even with different subjects, the relationships between the methods were similar. The study concluded the session RPE method is a valid way to quantify training during various types of exercise when objective monitoring is not possible.
This study investigated the effects of 4 weeks of zinc magnesium aspartame (ZMA) supplementation on strength and recovery in recreational male resistance athletes. 14 participants were randomly assigned to ingest either ZMA or a placebo daily for 4 weeks while performing a standardized resistance training program. Testing was conducted before and after the supplementation period to assess changes in 1 repetition maximum (1RM) strength on chest press, diverging row, and leg press exercises, as well as changes in sleep and recovery. The results showed a significant increase in leg press 1RM strength for those taking ZMA but no other significant changes in strength tests or recovery measures. The study concludes that ZMA may have limited benefits for strength and recovery and further research is needed.
This study examined the effects of caffeine supplementation on metabolic indices in female softball players. Eight female softball players completed a VO2max test on a treadmill after consuming either caffeine (6mg/kg) or a placebo. Results showed that caffeine significantly increased VO2max levels but did not significantly affect ventilatory threshold or time to exhaustion. This suggests that caffeine improves aerobic capacity but does not impact other metabolic thresholds during continuous exercise.
Cargas baixas e altas-adaptações-ao-trein0-de-força-schoenfeld2017.pdfFrancisco de Sousa
High-load (over 60% of 1RM) and low-load (under 60% of 1RM) resistance training protocols were compared in terms of strength and hypertrophy adaptations. A meta-analysis of 21 studies found that gains in maximum strength were significantly greater with high-load training, while increases in muscle size were similar between high-load and low-load training. The findings indicate that maximum strength benefits most from heavy loads, but muscle hypertrophy can be achieved equally across a range of loading intensities.
This study analyzed muscle activation in the abdomen and other areas of 7 commercial abdominal machines (Ab Slide, Ab Twister, Ab Rocker, Ab Roller, Ab Doer, Torso Track, SAM) and 2 common exercises (crunch, bent-knee sit-up) using electromyography. The results showed the Ab Slide and Torso Track activated abdominal muscles the most while minimizing back and hip muscle activation. Exercises like the Ab Doer, Ab Twister, and bent-knee sit-up activated back muscles more and may irritate existing back issues. Overall, different exercises activated various muscles to different degrees, providing information to help address individual rehabilitation or training needs.
This chapter provides background information on blood flow and muscle physiology relevant to the study. It discusses how blood flows through the body via the cardiovascular system, being pumped from the heart through arteries and returning through veins. It also covers concepts like capillary exchange, blood flow redistribution during exercise, and reactive hyperemia. The chapter then summarizes muscle structure, the mechanisms of muscle contraction, different muscle fiber types, and common adaptations to exercise like neurological, genetic, hypertrophic, and fatigue-resistance changes. Finally, it reviews related literature relevant to the study's hypotheses about changes in arm volume and blood flow after different exercise protocols.
corredores-de-distãncia-fatores-que-afetam-corrida-em-saunders2004.pdfFrancisco de Sousa
This document discusses factors that affect running economy (RE) in trained distance runners. It defines RE as the energy demand for a given running velocity, as measured by oxygen consumption. Good RE means using less oxygen and energy at a given speed. RE is correlated with distance running performance and is a better predictor of performance than maximal oxygen uptake in elite runners with similar fitness levels. The document examines how RE is measured, factors influencing it like physiology, biomechanics, and interventions that may improve it like strength training and altitude exposure. It emphasizes that improving RE could enhance distance running performance.
This document is a literature review and methods section from a honours project examining the relationships between exercise behaviour, stages of change, self-determination theory, and future time perspective. The literature review provides background on the stages of change model, self-determination continuum, and future time perspective theory. It indicates that higher stages of change are associated with more intrinsic motivation. The study aims to examine how future time perspective and self-determination relate to exercise behaviour and stages of change. The methods section describes using online questionnaires to measure these variables in university students and analyzing the results to address the study objectives.
This study aimed to compare quadriceps muscle activation and perceived exertion during the leg press and Smith machine squat exercises. The researchers measured muscle activation via EMG and perceived exertion ratings in athletes performing each exercise across a range of loads. They developed predictive equations to determine equivalent loads between exercises that produce the same muscle activation and perceived exertion. The muscle activation equation was less accurate due to individual variability, while the perceived exertion equation was more accurate as it reflects the overall exertion of each exercise rather than specific muscles. These equations provide a new tool to convert loads between exercises over a training period.
Respond to the 5 post below.100-200 wordsAPA FORMAT (NO TITLE PA.docxaudeleypearl
Respond to the 5 post below.100-200 words
APA FORMAT (NO TITLE PAGE NEEDED)
Due Sunday January 26, 2020
Adam J
1. After selecting and reading two of the provided articles, I was able to notice some differences and similarities between the two studies. As I read the article by Grenier and McGill (2007), the focus seemed to be on explaining the methods of improving lumbar stability and determining which of these two methods was more efficient at providing stability to this region. Through this study, Grenier and McGill found that when comparing abdominal hollowing and abdominal bracing, major differences could be found. In fact, through this study, we are able to see that the strategy of abdominal bracing provided a 32% improvement in the observed stability of the lumbar spine. Although Okubo, et al. (2010) were also concerned with lumbar stability, their study focused more on specific exercises that maximize specific abdominal muscle activation. The information presented by Okubo, et al. shows that different exercises are necessary if our goal is to improve the overall stability of our lumbar spine.
The information gleaned from the two articles described above are both important when working with a patient/client who has need of improving their spinal stability. After reading these two articles, I feel instructing a patient/client to incorporate an abdominal brace can help prevent injury from occurring during the prescribed exercise program. McGill (2016) also claims that his studies have shown an instant reduction in pain levels in many of his patients when abdominal bracing is used. When abdominal bracing is used in combination with the exercises described by Okubo, et al. (2010), I believe we can help patients/clients avoid injury during exercise, while also improving the overall stability of the spine by strengthening the muscles associated with lumbar stability.
Josh Y
2. I chose to review the articles by Ishida, Suehiro, Kurozumi, and Watanabe (2016) and Grenier and McGill (2007). Both studies made use of electromyography, which helped to quantify their data, rather than basing it on subjects’ perceptions of or description of what they felt during the study. The overarching purpose of both studies was to examine core stability and how different techniques contribute to core stability
Grenier and McGill (2007) examined abdominal hollowing and abdominal bracing. To test the two techniques, subjects were handed either a bilateral or asymmetrical weight in their hands. Electromyographic findings showed that the abdominal brace increased stability by 32%.
Ishida, Suehiro, Kurozumi, and Watanabe (2016) studied abdominal bracing and expiration in relation to sudden trunk loading. Subjects were loaded while at rest and while performing each of the stabilization techniques (expiration and bracing). The timing of when the loading would be applied was unknown to the subjects. There proved to be no difference between expiration and braci ...
Fisioterapia respiratoria toracica en neuminias en adultos.pdfJavierManriqueSoto1
This review analyzed 6 randomized controlled trials with 434 participants to evaluate the effectiveness of chest physiotherapy for pneumonia in adults. The review found that chest physiotherapy did not improve mortality or cure rates compared to no treatment or placebo. However, osteopathic manipulative treatment and positive expiratory pressure reduced the duration of hospital stay compared to no treatment. Additionally, positive expiratory pressure reduced fever duration and osteopathic manipulative treatment reduced intravenous and total antibiotic treatment duration compared to placebo or no treatment. The review was limited by the small number and size of included studies.
HIGH-INTENSITY CIRCUIT TRAINING USING BODY WEIGHTFernando Farias
Traditionally, resistance training often is
performed separately from aerobic training V
typically on two or three nonconsecutive days
each week. The American College of Sports
Medicine (ACSM) recommends 8 to 12 repeti-
tions of a resistance training exercise for each
major muscle group at an intensity of 40% to 80%
of a one-repetition max (RM) depending on the
training level of the participant.
The Discrepancy in Estimated VO2MAX Concerning Diverse PracticesCarl Page
This document summarizes a study that estimated VO2max (maximal oxygen consumption) levels in participants using various exercise tests. It found that estimates of VO2max can vary depending on the test used, and are also affected by individual factors like genetics, body composition, and training status. The study measured heart rate responses and oxygen consumption during tests like treadmill running, step tests, and 12-minute runs to estimate VO2max in participants and compare the results across tests. It concluded that more accurate VO2max measurements can be obtained in a laboratory setting using expired gas analysis compared to field tests.
The document outlines a learning module to teach students about family fitness and developing a health-related fitness (HRF) plan. It includes learning competencies, such as understanding the benefits of HRF, performing fitness tests, and designing physical activities to promote cardiovascular and muscular fitness for the family. Students are expected to create a comprehensive HRF plan for their family, assessing strengths and weaknesses, and providing exercise options. The document provides guidance on assessment, including criteria to evaluate students' HRF plans for their families.
This document reviews the macronutrient considerations for the sport of bodybuilding. It discusses that the major goals for competitive bodybuilders are to increase muscle mass in the off-season when there are no competitions, and to reduce body fat to very low levels while retaining muscle mass during the pre-contest period. The review provides recommendations for macronutrient intake and energy balance during the off-season and pre-contest phases to optimize these goals.
1. THE PENNSYLVANIA STATE UNIVERSITY
SCHREYER HONORS COLLEGE
DEPARTMENT OF KINESIOLOGY
THE EFFECTS OF VARYING LOADS AND REPETITIONS ON CALORIC
EXPENDITURE DURING TRADITIONAL BACK SQUATS
SAMUEL THOMAS BARRETT
Spring 2014
A thesis
submitted in partial fulfillment
of the requirements
for a baccalaureate
in Kinesiology
with honors in Kinesiology
Reviewed and approved* by the following:
Jinger S. Gottschall
Associate Professor of Kinesiology
Thesis Supervisor
Steriani Elavsky
Associate Professor of Kinesiology
Honors Adviser
* Signatures are on file in the Schreyer Honors College.
2. i
ABSTRACT
A leading topic of interest in the health-fitness and wellness industry is how to
maximize caloric expenditure in the shortest amount of time through physical activity.
The goal of this study is to identify a resistance training (RT) protocol that appeals to
these two demands through the use of the back squat exercise. A total of 15 subjects
between the ages of 18 and 40 participated in four separate exercise protocols in a
randomized order. Each protocol performed the same amount of work in the same 4
minute duration using either a 5kg, 10kg, 15kg, or 20kg load at a contraction speed of 1,
2, 3, or 4 seconds respectively. The mean physical activity energy expenditure (PAEE)
demonstrated a trend of decreasing as the loading increased from 5kg to 20 kg with a
29.3% difference between the 5kg and 20gk condition values. All of the mean heart rate
(HR) recordings exhibited a similar trend of decreasing as loading increased from 5kg to
20kg with the exception of the mean minimum HR (MNHR) measurements in which case
the largest value was associated with the 10 kg load as opposed to the 5kg load. The
mean values for MNHR indicated an 8.7% difference between the 10kg condition and the
20kg condition while the 5kg condition displayed a 4.9% difference. For the average
heart HR (AHR) values, there proved to be a 13.4% difference between the 5kg and 20kg
conditions while the maximal HR (MXHR) values showed a 13.8% difference. In
conclusion, using a work load that maximizes the total work output as a result of a high
capacity for the number of repetitions performed at the fastest rate of contraction will
most likely yield the highest PAEE.
3. ii
TABLE OF CONTENTS
List of Figures..........................................................................................................................iii
List of Tables ...........................................................................................................................iv
Acknowledgements..................................................................................................................v
Chapter 1 -Introduction............................................................................................................1
Background......................................................................................................................1
Purpose.............................................................................................................................6
Hypothesis........................................................................................................................9
Chapter 2 –Review of Literature..............................................................................................11
Review of Heart Rate Monitor Literature ........................................................................11
Review of Physical Activity Energy Expenditure Literature...........................................12
Chapter 3 -Methods..................................................................................................................20
Subjects............................................................................................................................20
Equipment........................................................................................................................21
Experimental Procedure...................................................................................................21
Statistical Analysis...........................................................................................................24
Chapter 4 -Results....................................................................................................................25
Chapter 5 -Discussion..............................................................................................................29
Practical Applications ......................................................................................................36
Limitations .......................................................................................................................38
Future Studies ..................................................................................................................38
REFERENCES.................................................................................................................40
4. iii
LIST OF FIGURES
Figure 1. Subjects performing the 10kg squat protocol...........................................................24
Figure 2. Mean MNHR (bpm) as a result of performing a four minute protocol for each of
the four conditions ranging from low-load high-repetition fast contractions (5 kg) to
high-load low-repetition slow contractions (20kg). .........................................................25
Figure 3. Mean AHR (bpm) as a result of performing a four minute protocol for each of
the four conditions ranging from low-load high-repetition fast contractions (5 kg) to
high-load low-repetition slow contractions (20kg). .........................................................26
Figure 4. Mean MXHR (bpm) as a result of performing a four minute protocol for each of
the four conditions ranging from low-load high-repetition fast contractions (5 kg) to
high-load low-repetition slow contractions (20kg). .........................................................26
Figure 5. Mean PAEE as a result of performing a four minute protocol for each of the
four conditions ranging from low-load high-repetition fast contractions (5 kg) to
high-load low-repetition slow contractions (20kg). .........................................................27
5. iv
LIST OF TABLES
Table 1 BMI Body Weight Classifications..............................................................................8
Table 2. Subject Information ...................................................................................................20
Table 3. Resistance Training Protocols....................................................................................23
Table 4. Mean Values of HR and PAEE for all Conditions.....................................................28
6. v
ACKNOWLEDGEMENTS
First, I would like to extent a huge thank you to my thesis supervisor Dr. Jinger
Gottschall. Her unwavering optimism and encouragement enabled me to continue putting
one foot in front of the other during times of both logistical and emotional struggle
throughout the thesis process. It goes without saying that this project would not have
been possible without her guidance and enthusiasm. She is without question one of the
most outstanding individuals I have had the pleasure of meeting.
Second, I would like to thank my honors advisor Dr. Steriani Elavsky who has, on
several occasions, gone above and beyond expectations in her efforts to find the answers
to whatever questions I may have had. She kept me on task with deadline reminders and
even took the time to set up appointments in order to touch base and ensure that we were
on the same page with my course schedule. My years at University Park would have
definitely been a whole lot more chaotic if it weren’t for her help.
Lastly, I would like to especially thank all of my friends and family whom
without their relentless support I may not have made it through my undergraduate years
at all. They took the time to take an interest in my own and even now continue to
motivate me to succeed at whatever I set my mind to. Time and time again they were able
to remind me of the light at the end of the tunnel and refused to allow me to throw in the
towel. Thank you all so much, it is a debt for which I may never be able to repay, but that
won’t stop me from trying.
7. 1
Chapter 1 -Introduction
Background
Including regular resistance training into either a currently active or previously
inactive lifestyle has obtained substantial awareness over the past few decades regarding
its many health benefits consisting of improved strength, bone density, body composition,
anaerobic capacity, flexibility, physical function, and more. The importance of resistance
training for improved health and well-being was recognized by the American College of
Sports Medicine (ACSM), American Heart Association, and Surgeon General's Report on
Physical Activity and Health (Robergs, 2007). Tremendous progress has been made in
our attempt to understand the many benefits of resistance training and the key variables
that govern the extent to which those benefits are experienced.
A few variables that have been tested already include measurements of relative
muscular effort (RME), effects of load-volume, rate of contraction, work performance,
and repetition cadence. RME refers to the muscle force implemented during a particular
task relative to the maximum amount of force the muscle is capable of producing. Load-
volume relates the magnitude of the training load to the total amount of accumulated
mass lifted. The rate of contraction concerns the degree of acceleration that takes place
while displacing the training load through its designated range of motion. The total
amount of force generated to move a particular mass through a particular distance
dictates the total amount of work performed, while the pace at which each phase of a lift
8. 2
is executed will determine the repetition cadence. One commonality between these
variables is a direct influence on physical activity energy expenditure (PAEE).
Physical activity may be defined more broadly as all bodily actions produced by
the contraction of skeletal muscle that increase energy expenditure (EE) above basal level
(Butte, 2012). PAEE is the most variable portion of any individual’s total energy
expenditure (TEE) and can range from as little as 5% of the TEE to 45-50% depending
on their physical activity level. Numerous methods for measuring PAEE have been tested
and evaluated including heart rate (HR) monitors. These devices have been used to
incorporate the FLEX HR technique for measuring PAEE which has proven to be a valid
and reliable method on the basis of the linear relationship between HR and EE (Butte,
2012).
The back squat is a common exercise utilized in a multitude of settings ranging
from clinical rehabilitation to strength and conditioning for athletic performance. This is
because there are so many similar movements demonstrated in numerous activities of
daily living in cultures all over the world as well as athletic movements. Additionally, it
is a multi-joint exercise requiring various large muscle groups to function in an organized
manner. From a performance perspective, both in terms of simple functional movements
to ease activities of daily living as well as athletic performance, the back squat exercise
will benefit both the joint structures themselves, by strengthening the ligaments, tendons,
and bones that constitute them, as well as the physical functions such as strength, speed,
power, and neuromuscular efficiency of the muscles that cross those joint structures. This
is especially true for the knee, hip, and low-back joint structures which perform most of
the work. A strong correlation between speed as well as relative and absolute strength has
9. 3
been found as a result of exploiting free weight squats in particular (Keiner, 2013). When
participating in RT exercises such as the back squat, it is important to perform each
repetition through a full range of motion (ROM) as recommended by the American
College of Sports Medicine. By doing so, strength adaptations may occur at each angle
within the ROM which may lead to enhanced injury prevention due to the strengthening
of the various joint structures as previously mentioned (Cotter, 2013).
Despite all of the benefits that may be acquired from squats as part of a RT
program, if the movement is not executed properly the risk for injury could substantially
increase. Therefore proper execution of the exercise is essential to minimizing this risk.
The back squat is often performed following two common sets of instructions regarding
proper form. In one case, the knees are not allowed to pass over the toes during the lift. In
the other case, the knees are allowed to pass over the toes during the lift. A study
performed by List et al. (2013) found that restricting the distance traveled by the knees
results in an increased range of motion for thoracic curvature leading to higher stresses in
the hips and low-back. When the knees were allowed to pass over the toes during the lift,
a larger ROM was demonstrated in the knees and to a much lesser degree in the thoracic
curvature and other spinal segments leading to lower stresses in the back and a larger
capacity for strength training of the leg muscles. This would suggest that squatting
instructors should be more open to allowing anterior knee displacements slightly beyond
the position of the toes (List, 2013).
An alternative mode in which the squat exercise is often manipulated concerns the
technique that is used to reverse the movement once the desired depth has been
established. In one case a momentary pause is demonstrated before reversing the
10. 4
movement in which case there is no rebound effect to alter the movement mechanics. In
the second case there will be a rebound effect to introduce an element of bouncing out of
the end range of depth. With the work and load being standardized between both the
rebound and no rebound modes of squatting, the rebound uses less oxygen and in effect
proves to be significantly more efficient in its energy cost. It is suggested that the
increased efficiency is the result of an elastic recoil effect from the muscles and tendons.
As the muscle-tendon unit is stretched at the bottom of the movement, elastic potential
energy is stored and then reconverted into kinetic energy upon reversing the movement
back towards the standing position (Villagra, 1993).
One of many factors effecting caloric expenditure during exercise is the effort
displayed by muscle groups that cross all participating joint structures. For multi-joint
exercises it is unknown whether all of the muscle groups involved have the same relative
muscular effort (RME), which can be defined as the muscle force needed to perform a
task relative to the maximum force that muscle can produce, or not (Bryanton, 2012). In
the case of the back squat exercise, there are two manipulations that can be made to
influence the RME of the muscles involved, more specifically the muscles responsible for
the necessary joint rotations to perform the movement including the ankle plantar flexors,
knee extensors, and hip extensors. These two manipulations consist of the depth to which
the squat is performed and the magnitude of the load (Bryanton, 2012).
Another energetic influence along the lines of muscular effort that has drawn
some attention is the rate of muscular contraction while performing a particular exercise.
It had been widely accepted since the 1990’s that resistance training with an emphasis on
PAEE should be performed using slow muscle contractions. One argument for this
11. 5
reasoning claims that slow repetition speeds increase the workout’s intensity and
effectiveness (Mazzetti, 2007). Exercise intensity may be defined by both the training
load’s percentage of the individual’s 1RM and the rate of acceleration at which the
training load is moved. Since neither of these factors will increase by using slower
repetition speeds, the exercise intensity will not increase either. Slow contractions instead
only prolong repetition durations resulting in greater muscle fatigue and apparent
muscularity due to an increase in blood flow to the muscle, neither of which contributes
to EE efficiency.
On the contrary there has also been evidence supporting explosive muscle
contractions as having a higher PAEE rate due to the activation of the energy-inefficient
fast twitch muscle cells (Ferguson, 2001; Mazzetti, 2007; He, 2000). For a muscle to
generate more force it either has to increase the frequency of contractions for all active
muscle cells, recruit more muscle cells through the activation of higher-recruitment
threshold motor nerves (Behm 1993; Grimbly 1977), or a combination of the two. High-
recruitment threshold motor nerves are known to have a higher synapse proportion with
fast muscle cells further reducing the energy efficiency during force production
(Mazzetti, 2007; Schiaffino, 1970).
The intense physiological and metabolic reactions to RT are the result of
mechanical stimuli. These stimuli are defined by multiple criteria that ultimately result in
various training methods. Such variables involved in previous studies have included
loading, contraction velocity, exercise volume, repetition cadence (i.e. eccentric,
concentric, and isometric contraction durations), and rest interval duration. These aspects
ultimately dictate the power being generated and the work being performed while at the
12. 6
same time determining the PAEE (Buitrago, 2013; Villagra, 1993). A few of the
physiological and metabolic reactions investigated during the different training methods
so far have been the rate of EE, oxygen uptake (VO2), lactate concentration, HR, and
excess post-exercise oxygen consumption (EPOC) (Buitrago, 2012, 2013). Disparities in
the metabolic and physiological reactions to different RT methods emphasizing the
different mechanical stimuli may reveal a more accurate specification of their
effectiveness at achieving particular training goals (Buitrago, 2013).
Purpose
Despite the awareness of all the benefits tied to participating in regular exercise,
the majority of American adults still fail to engage in even the minimum exercise
recommendations. There are currently two methods of how to achieve the recommended
levels of exercise by ACSM, the Center for Disease Control, and the Office of the
Surgeon General. The first and earliest method was based on the assumption of
increasing exercise intensity (vigorous) to improve health as a result of first improving
fitness levels and recommended that individuals exercise at a minimum intensity of 50%
of their maximal oxygen uptake reserve 3-5 days per week. The more modern
recommendation of exercising at a minimal intensity of 40% of their maximal oxygen
uptake reserve 5-7 days per week is based on public health objectives and appreciates the
value of physical activity levels (low to moderate) that improve health without
necessarily improving personal fitness. This was accomplished by lowering the minimum
intensity required while increasing the frequency of participation. In addition, the
13. 7
duration of exercise became more flexible by allowing for multiple bouts of shorter
exercise periods to reach the recommended duration. Many of these changes were largely
made under the assumption that lowering the exercise intensity will result in improved
exercise adherence. Although this assumption rings true with 23% of American adults
participating in low to moderate physical activity levels five or more times per week
compared to the 15% who participate in vigorous physical activity three or more times
per week, these numbers are still far too low (Kilpatrick, 2007).
Obesity in the United States is currently classified as an epidemic and is
significantly perpetuated by these sedentary lifestyle habits among other factors such as
poor dietary options. The current circumstances confirm a need to introduce this
population to physical activities geared toward maximizing their impact on weight
management. Despite the growing concerns, documented evidence of the increasing
prevalence and efforts to emphasize physical activity and proper nutrition, obesity has
continued to root itself within the American population. In 2000, no states reported a
pervasiveness of obesity ≥30%, but by 2009 nine states had surpassed that number. Only
one year before that, in 2008, the prevalence of obesity in the United States had reached
an overall 33.8% between men and women (Menez, 2013).
The anthropometric tool of choice most commonly utilized to assess relative
weight and classify it into such categories as underweight, normal, overweight, and obese
is body mass index (BMI). BMI is expressed as the individual’s body weight in
kilograms over their height in meters squared (kg/m2
). The ranges for each category are
broken down as such:
14. 8
Table 1. BMI Body Weight Classifications
Classification of Body Weight BMI Range (kg/m2
)
Underweight < 18.5
Normal Weight 18.5 – 24.9
Overweight 25 – 29.9
Obese ≥ 30
Grade 1 30 – 34.9
Grade 2 35 – 39.9
Grade 3 ≥ 40 (Severe Obesity)
Since the first expansion of the obesity subgroup (grades 1-3), the American
Heart Association has proposed to once again expand it into additional subgroups of
grades 4 and 5 to classify BMI values of ≥ 50 kg/m2
and ≥ 60 kg/m2
respectively.
However, this method of classification is notorious for its inability to distinguish between
lean and fat body mass especially in patients with BMI ≥ 30 kg/m2
(Bastien, 2014).
It is primarily the acquisition of excess body fat that is more often connected to
metabolic abnormalities. For this reason obesity has been linked to elevated morbidity
and mortality rates. Obese individuals are more susceptible to acquiring diseases such as
coronary disease, hypertension, and type 2 diabetes mellitus. The increased mortality rate
of these individuals is the result of a higher susceptibility to cardiovascular disease, renal
failure, obesity-related cancers, and diabetes (Menez, 2013).
With a better understanding of how to maximize PAEE from RT, individuals who
are currently classified as obese, at risk for becoming obese, or simply prefer to maintain
or improve their body composition, will have an easier time achieving these goals. In a
fast paced world where a lot of reward for little effort is highly desirable, especially in the
weight management category, efficiency is of the utmost importance in order to keep
individuals motivated and on task. Knowledge of whether or not one RT method truly
15. 9
surpasses others in its ability to influence PAEE would be vital to a number of
professionals including physicians, physician assistants, fitness trainers, physical
therapists, and more. But above all, the most important population to reach with this
information would be the general public to make use of it themselves before reaching a
point where a health care professional feels the need to intervene.
Hypothesis
Previous studies have only examined one or possible even a few of the variables
previously mentioned (RME, load-volume ratios, rate of contraction, and multiple
training methods) and may or may not have focused on or even considered the
contribution to PAEE (Abboud, 2013; Behm, 1993; Bryanton, 2012; Buitrago, 2012,
2013; Ferguson, 2001; Grimbly, 1977; He, 200; Schiaffino 1970). Attributes and findings
from these various studies need to be incorporated into a single study with the intent of
understanding how they contribute to the resulting PAEE. This would require the study to
incorporate multiple training methods for comparison, consider depth and loading for
each training method, and maintain a standardized work output and time constraint with a
spectrum of varying contraction speeds ranging from very fast to very slow. With each
training method performing the same amount of work over the same amount of time it
will be much more clear as to which, if any, ratio of loading to number of repetitions,
ultimately dictating the contraction speed, has a higher rate of PAEE.
16. 10
We hypothesize that the training method with the lowest loading and highest
number of repetitions, therefore having the fastest muscle contractions, will result in the
most significant PAEE. Based on the data collected from previous studies about the
magnitude of influence from quicker contraction speeds on increased energy expenditure,
possibly due to the recruitment of energy inefficient motor units (Mazzetti, 2007), we
believe this will supersede the influence of heavier loads with slower contraction rates.
Not only will the faster contraction condition likely recruit the highest proportion of less
energy efficient muscle fibers, but it will do so far more often than any of the slower
conditions throughout the duration of the protocol. Following this logic, we even expect
to see a trend of the highest PAEE resulting from the fastest contraction speed and then
continuing to decrease as the contraction speed decreases.
17. 11
Chapter 2 –Review of Literature
Review of Heart Rate Monitor Literature
A commonly accepted claim is that activities of daily living correspond to
submaximal exercises ranging from low to moderate intensities. For this reason the HR
method for measuring EE does not consider the constraints of daily physical activities
and is not a good predictor of EE for low activity levels (Gastinger, 2012). When
compared to the EE measured from breath-by-breath gas exchange using an indirect
calorimetry system, HR monitors demonstrate significant differences in measurements
while standing at rest for an individual and while standing at rest or walking at 5 and 6
km/hr for a group (Gastinger, 2012). These differences are a testament to the inaccuracies
of HR monitors at low to moderate activity levels. Advantages to using HR monitors
include portability, ease of use, and that they are non-invasive.
Due to the overlap between active and sedentary HR, a threshold value must be
established to discriminate between the two. Studies planning to utilize the HR monitor
method are better off applying it to a group setting due to measures of the prediction
errors for the group mean being as low as 3%, whereas for individuals the range of
prediction errors were greater than 10%. More considerations to be taken into account
when using these monitors is the necessity to calibrate them for use on individuals taking
prescription drugs that may affect HR (Butte, 2012). HR is also subject to additional
factors such as activity mode, posture, environmental conditions, and fitness levels
18. 12
(Gastinger, 2012). More accurate measurements will arise from addressing more of the
previously stated criteria.
Review of Physical Activity Energy Expenditure Literature
Physical activity is a construct that can be defined both qualitatively and quantitatively.
Qualitatively, it can be placed into different categorizations depending on how taxing the activity
is to an individual’s aerobic and anaerobic energy systems. Ranging from least to most activity,
such categories may include sedentary behaviors, locomotion, leisure activities, and exercise.
Quantitatively, exercise can be classified based on the frequency at which the activity is
participated in, the duration of the activity, and the intensity of the activity (Butte, 2012). PAEE is
highly variable among individuals and depends on what the activity is, how often it is performed,
for how long, and how much physiological effort is exerted in the process.
Bryanton (2012) investigated to methods, consisting of barbell loading and depth,
to influence the RME while performing a barbell back squat. The results for this study
showed that increasing the barbell load affected the ankle plantar flexor RME, increasing
the squat depth affected knee extensor RME, while both affected hip extensor RME.
More specifically, knee extensor RME was shown to be lowest between 30 and 44
degrees of knee flexion, and highest between 105 and 119 degrees of knee flexion. No
significant difference in knee extensor RME was seen from 60-74 degrees and 90-104
degrees of knee flexion (Bryanton, 2012). With both elements playing a role in the
resulting RME, both need to be considered when evaluating the difference in caloric
expenditure for the same exercise under different conditions.
19. 13
In order to take a closer look at the influence of contraction speed on PAEE
Mazzetti (2007) compared three separate squat exercise protocols focused on explosive
versus slow muscle contraction to a baseline measurement. Measurements taken during
each protocol consisted of total oxygen consumption from expired air using a metabolic
cart calibrated for each experiment as well as blood lactate accumulation from finger-
prick blood samples. All familiarization and testing performed by each subject was done
using a plate loaded squat machine. The first protocol (SLOW) required two seconds for
both the eccentric and concentric contractions for a total of four seconds using a 60%
1RM load. This was done for four sets of 8 repetitions with 90 seconds of rest in
between. The second protocol (EXPL) followed all of the same criteria for the SLOW
squat with the exception of an explosive concentric contraction phase lasting about one
second. The final protocol (HEAVYEXPL) used a two second eccentric phase with an
explosive concentric phase to lift an 80% 1RM load for six sets of four repetitions with a
90 second rest interval.
The total amount of work performed was the same for all three protocols;
however the time it took to perform the total amount of work was longer for the SLOW
protocol compared to the EXPL and HEAVYEXPL protocols which were equal in
duration. Mazzetti (2007) found that using a moderate load with explosive concentric
contractions yields a significantly higher total oxidative energy expenditure as well as a
higher total oxidative energy expenditure plus anaerobic energy expenditure than that of a
slow contraction or heavy explosive protocol. Finally, the average rate of energy
expenditure for the explosive contraction protocol was also significantly greater than the
slow contraction and heavy explosive contraction protocols (Mazzetti, 2007). This may
20. 14
suggest that the use of lighter weights with quicker contraction rates may prove to be the
more effective method of reaching weight management goals through RT.
Buitrago (2012) performed a study concerned with the effects of different loads
and modes at which each repetition is performed and focused on how these two factors
influence blood lactate concentration, oxygen uptake, HR, exercise time, number of
repetitions, and accumulated lifted mass. Subjects were tested for a 1RM to define the
individualized loads that would be utilized for each condition. A total of three different
loads consisting of 55%-1RM (LOW), 70%-1RM (MID), and 85%-1RM (HIGH) were
used to perform a single set of resistance training using a seated bench press machine.
Each set was performed using one of four different exercise modes defined as 4-1-4-1 (4-
s concentric, 1-s isometric, 4-s eccentric and 1-s isometric successive actions), 2-1-2-1
(2-s concentric, 1-s isometric, 2-s eccentric and 1-s isometric successive actions), 1-1-1-1
(1-s concentric, 1-s isometric, 1-s eccentric and 1-s isometric successive actions), and
MAX (maximum velocity concentric, 1-s isometric, 1-s eccentric and 1-s isometric
successive actions). Oxygen uptake measurements were taken using an open air
spirometry system which began 10 minutes prior to exercise beginning and continued to
be taken for 30 minutes post-exercise. Blood lactate was determined by an enzymatic-
amperometric analyzer from blood samples taken from the ear lobe while HR was
recorded using a Polar telemetric HR-system. Measurements for both blood lactate and
HR were taken every two minutes post-exercise for 30 minutes. Finally, for each of the
12 possible conditions the number of repetitions completed was recorded as well as the
exercise duration. The accumulated lifted mass was calculated by multiplying the number
of repetitions by the mass lifted.
21. 15
Both load and mode significantly affected the number of repetitions performed.
As load decreased, the number of repetitions performed significantly increased. However,
the number of repetitions increased with increasing mode except in the case of 1-1-1-1
and MAX where there was no significant difference. Exercise time was also effected by
load and mode in which case it was significantly higher at LOW loads compared to MID
and HIGH loads. MID loads also demonstrated a significantly longer exercise time
compared to HIGH. In the case of exercise mode, 4-1-4-1 resulted in a significantly
higher exercise time than that of the 2-1-2-1, 1-1-1-1, and MAX. There was no
significant difference between 2-1-2-1, 1-1-1-1, and MAX modes. Accumulated mass
lifted decreased significantly between all loads as they increased, but increased as the
speed of the repetitions increased except between 1-1-1-1 and MAX in which case there
was no difference. Oxygen uptake was significantly different depending on the load
being used. LOW load showed the highest oxygen uptake followed by MID and then
HIGH, but there was no significant difference between MID and HIGH. Mode also
showed no significant difference for oxygen uptake. Blood lactate concentrations were
significantly higher for LOW and MID loads compared to HIGH load, but with no
significant difference between LOW and MID. Different modes showed no change in
blood lactate concentrations. No significant difference was detected in HR between all of
the different loads and modes (Buitrago, 2012).
In an effort to describe the relationship between EPOC and RT, Abboud (2013)
investigated the effects of load-volume on EPOC after acute bouts of resistance training
in resistance-trained men. Eight individuals performed two RT sessions of equal intensity
but different totals of accumulated mass lifted consisting of 10,000 and 20,000 kg.
22. 16
Resting metabolic rate (RMR) was assessed before and after exercise at multiple time
intervals. Rating of perceived muscle soreness and creatine kinase levels were also
measured in order to determine if differences in EPOC may have been associated with the
differences in the degree of muscle damage inflicted by the exercise protocols. No
significant difference in RMR as a result of EPOC was demonstrated over time or
between conditions. However, the results of the study did show that the 20,000 kg session
was significantly longer and expended a significantly larger amount of energy. Abboud
(2013) suggests that because of the training condition of the subjects they had reached a
higher level of adaptation to the stresses of exercise and were therefore less responsive to
the metabolic effects of recovery from RT. These results may advocate the exclusion of
EE due to EPOC while testing trained subjects for PAEE as a result of RT.
RT is highly variable and adaptable to meet the demand of the desired effect such
as hypertrophy, functional capacity, energy balance, and weight management (Buitrago,
2013). For this reason there is a wide array of training methods that can be adopted to fit
the individual’s needs. Buitrago (2013) tested four different training methods to highlight
the advantages of each. The first method focused on strength endurance and utilized a
55% 1RM with four second concentric and eccentric contraction phases for each
repetition. The second training method focused on fast force endurance which used the
same loading as the strength endurance method but incorporated an explosive concentric
contraction phase and reduced the eccentric contraction phase to one second. The third
training method was designed for hypertrophy and used a 70% 1RM load with two
second concentric and eccentric contraction phases. The final training method focused on
23. 17
maximum strength with an 85% 1RM load and applied an explosive concentric phase
with a one second eccentric phase.
Buitrago’s results showed that the total concentric power involved in each
training method was significantly higher for the fast force endurance and maximum
strength methods. The fast force endurance method also proved to produce a significantly
higher amount of total concentric work than the other three methods. When comparing
the total exercise time, the strength endurance method measured significantly higher than
the others while the maximum strength method measured significantly lower. Oxygen
consumption was measured to be significantly higher in the strength endurance than the
hypertrophy and maximum strength methods. Maximum blood lactate concentration was
significantly higher in the fast force endurance method when compared to the maximum
strength method. No significant difference for EPOC was measured for any of the four
training methods. By determining the generated power and the work performed, the
energy demands of the exercise can also be determined. Buitrago (2013) concludes that
the fast force endurance training method will consume the most energy because it
measured significantly higher in the concentric work and power categories. However, this
relationship discloses no information about the quantity of energy consumed or the
contribution of aerobic and anaerobic metabolism to the total energy supply. Mazzetti
(2007) and Buitrago (2013) have both drawn the same conclusion regarding training
methods utilizing explosive contractions suggesting that this factor seems to play a
significant role in maximizing PAEE.
Continuing with specificity of training mode to training results, one study
compared traditional strength (TS) training programs, which include rest intervals
24. 18
between sets of heavier loads, to high-resistance circuit (HRC) training including
relatively low loading with minimal rest between sets (Romero-Arenas, 2013). Healthy,
untrained elderly men and women between the ages of 55-75 years were randomly
assigned to the TS, HRC, or control group. Measurements of the isokinetic peak torque
were taken in both upper and lower body extremities as well as peak VO2 and body
composition for each subject. Both training programs consisted of exercising two times
per week for 12 weeks. The TS training program required subjects to complete two warm
up sets of each exercise for six exercises with 1 and 2 minutes of rest in between
respectively before starting the first working set of the subject's 6RM. The number of
working sets performed each week varied according to a specific periodized training
program. Three minutes of rest were taken between each working set and each exercise
for the first three exercises (leg curl, pec deck, and seated calf raise) until a five minute
rest period was given before starting the next three exercises (seated pulley row, leg
extension, and preacher curls). The same warm up and working sets of 6RM were used
for these three exercises as well.
The only difference between the TS and HRC training programs was the rest
interval between exercises and the progression through the exercises. For both training
programs the eccentric phase of each repetition was performed for three seconds while
the concentric phase was performed at maximum velocity. The HRC training program
was broken up into two circuits of the same six exercises, the first including the leg curl,
pec deck, and seated calf raises, while the second included the seated pulley, leg
extension, and preacher curls. For the HRC training program the first set of the first three
exercises, including the same warm up and working sets, was performed in series with 35
25. 19
seconds of rest in between each exercise. After finishing a set of the last exercise in the
sequence, three minutes of rest were allotted before beginning the second series of sets
and so on until the required number of working sets was completed. Five minutes of rest
were allowed between the end of the first circuit and the start of the second circuit which
followed the same exercise and rest intervals as the first circuit. Both the TS and HRC
groups demonstrated significant increases in isokinetic strength previous to beginning the
training programs and were also significantly greater than the mean of the control group.
Also, both TS and HRC groups showed significant increases in lean mass and
bone mineral density, but only the HRC group showed a significant decrease in fat mass
which was also significantly greater than the decrease in the control group. The walking
economy of the HRC group also experienced a significant increase although there was no
significant different between each group. Therefore both TS and HRC prove to be
effective in increasing isokinetic strength, lean mass, and bone mineral density, but only
the HRC program provokes a significant decrease in fat mass and improves
cardiovascular adaptations accomplishing this through the reduction of rest intervals
alone (Romero-Arenas, 2013).
26. 20
Chapter 3 -Methods
Subjects
A total of fifteen subjects, six males and nine females, participated in the
experiment and were between ages 18 and 40. Each had a minimum of two years of
weightlifting experience and participated in weekly exercise training sessions that include
squats. All of the experimental procedures and formalities were approved by the
Institutional Review Board for the involvement of human participants. The procedures
were disclosed to all participants both verbally and in writing. Written consent was
received from each individual prior to their involvement in the experiment.
Table 2. Subject Information
Age 29.91 ± 6.72
Height (inches) 65.53 ± 4.19
Height (meters) 1.66 ± 0.11
Weight (lbs) 147.2 ± 28.33
Weight (kg) 66.91 ± 12.88
Data are means ± SD.
27. 21
Equipment
Each subject was fitted with a wireless Polar Team2
heart rate monitor prior to
beginning the experiment. Additional equipment used during each trial included a Les
Mills SMARTBARTM
as well as Les Mills SMARTBARTM
weight plates (2.5kg and 5kg)
for each subject. Tape was placed on the floor to mark the stance width and angle of the
feet for each participant. A metronome was also utilized to set and maintain the pace of
each repetition for each of the different exercise protocols.
Experimental Procedure
Data collection for this experiment was administered over a single session for
each subject. Prior to each subject’s participation in the experiment, a 10 minute cycling
warm up was administered to prepare for the physical activity involved. Following the
warm up each subject was fitted with a heart rate monitor and performed a short squat
routine involving the squat counts from each of the four protocols in order to give each of
the subjects a chance to establish a comfortable squatting stance and familiarize
themselves with the pacing of each protocol. During this time tape was placed along the
medial length of each foot marking the preferred squatting stance to ensure the
consistency of joint angles across all trials. Following the squat warm up the subjects
were given 2-3 minutes to establish a baseline HR which played two major rolls. First, it
allowed each subject to act as their own control, serving as a base for comparison of any
changes that took place throughout the four protocols. Second, after the completion of
each protocol, subsequent protocols could only be performed following the restoration of
28. 22
the baseline HR. A metronome was set to beep at the required pace for each protocol to
promote consistent results by ensuring that the same number of repetitions were
performed at the same pace for each subject during each protocol. At the sound of each
beep from the metronome, the subject would either have reached the proper depth at the
end of the eccentric portion of the lift or would have returned to the full standing position
at the end of the concentric portion of the lift.
Each of the four exercise protocols was performed over a four minute duration for
each subject with rest intervals in between to reestablish baseline heart rates. The first
protocol used a 20 kilogram load and performed each repetition with a four second count
for both the eccentric and concentric portions of the lift for a total of 30 repetitions over
the four minute period. The second exercise protocol incorporated a 15 kilogram load and
performed each repetition with a three second count for both the eccentric and concentric
portions of the lift for a total of 40 repetitions over the four minute duration. The third
exercise protocol utilized a 10 kilogram load and performed each repetition with a two
second count for both the eccentric and concentric portions of the lift for a total of 60
repetitions over the four minute duration. The final exercise protocol applied a 5 kilogram
load and performed each repetition with both a one second eccentric and concentric
portion of the lift for a total of 120 repetitions over the four minute duration. These
particular loads and repetition rates were specifically designed to ensure that each
protocol performed the same amount of work. The order of each of the four exercise
protocols was randomized for each set of 3-4 subjects to ensure the results were not
skewed as a result of fatigue.
29. 23
Table 3. Resistance Training Protocols
Resistance
Training
Condition
5 kg 10 kg 15 kg 20 kg
Contraction
Mode
c-e c-e c-e c-e
Repetition
Cadence (s)
1-1 2-2 3-3 4-4
*c = concentric phase, e = eccentric phase
The range of the loading involved was chosen to accommodate a wide range of
participants and allowed them all to handle the weight with minimal to no assistance.
Each subject would position the bar just under the spinous process of their C7 vertebrae.
Once each set of subjects were situated and comfortable, the metronome would be set to
the proper pacing for each repetition and begin to beep. The data recording began at the
start of the second repetition in order to allow each subject a practice repetition to adjust
to the pacing. All squats were performed in front of a mirror, allowing each subject to
monitor their own consistency, and to a depth where the hips were roughly two inches
above parallel with the knees. After each protocol was completed, the subjects would
remove the loaded bar from their back and place it on the floor where the weights would
be replaced with the proper loading for the next protocol. The data of interest recorded
from each subject for each protocol was the minimum HR (MNHR), average HR (AHR),
and maximum HR (MXHR) which were ultimately used to calculate the total PAEE for
each condition which was also recorded.
30. 24
Figure 1. Subjects performing the 10kg squat protocol
Statistical Analysis
Averages were calculated for each of the minimum, average, and
maximum heart rates as well as the total caloric expenditure for each protocol. The data
is represented as means ± standard deviations (SD). An ANOVA was performed to
compare the means of each protocol in order to assess how statistically different they
were from one another, specifically, the means of the minimum, average, and maximum
HR as well as the total PAEE. Following the ANOVA, a Tukey post-hoc analysis was
run between all conditions to assess how statistically different the means for each
condition were from the other three conditions. Statistical significance was defined as P ≤
0.05 for this study.
31. 25
Chapter 4 -Results
Mean PAEE demonstrated a trend of decreasing as the loading increased from
5kg to 20 kg with a 29.3% difference between the 5kg and 20gk condition values. The
differences in mean HR for the minimum, average, and maximum measurements as well
as the PAEE are displayed as a visual comparison in Figures 1-4 and are also listed in
Table 4 represented as the means ± SD.
Figure 2. Mean MNHR (bpm) as a result of performing a four minute protocol for each of
the four conditions ranging from low-load high-repetition fast contractions (5 kg) to high-
load low-repetition slow contractions (20kg).
32. 26
Figure 3. Mean AHR (bpm) as a result of performing a four minute protocol for each of the
four conditions ranging from low-load high-repetition fast contractions (5 kg) to high-load
low-repetition slow contractions (20kg).
Figure 4. Mean MXHR (bpm) as a result of performing a four minute protocol for each of
the four conditions ranging from low-load high-repetition fast contractions (5 kg) to high-
load low-repetition slow contractions (20kg).
33. 27
Figure 5. Mean PAEE as a result of performing a four minute protocol for each of the four
conditions ranging from low-load high-repetition fast contractions (5 kg) to high-load low-
repetition slow contractions (20kg).
All of the mean HR recordings exhibited a similar trend of decreasing as loading
increased from 5kg to 20kg with the exception of the mean MNHR measurements in
which case the largest value was associated with the 10kg load as opposed to the 5kg
load. The mean values for MNHR indicated an 8.7% difference between the 10kg
condition and the 20kg condition while the 5kg condition displayed a 4.9% difference. In
regards to the AHR values, there proved to be a 13.4% difference between the 5kg and
20kg conditions while the MXHR values showed a 13.8% difference.
34. 28
Table 4. Mean Values of HR and PAEE for all Conditions
Condition Min HR Ave HR Max HR kcal
5 kg 104 ± 20 135 ± 23 147 ± 26 47 ± 15
10 kg 108 ± 22 127 ± 25 137 ± 27 42 ± 17
15 kg 99 ± 17 120 ± 22 132 ± 26 38 ± 13
20 kg 99 ± 16 118 ± 18 128 ± 25 35 ± 12
Data are means ± SD.
The mean values in each category for each condition were compared to one
another using a Tukey post-hoc analysis to determine their statistical differences (P ≤
0.05). The 5kg condition registered a significant difference in AHR (P < 0.01), MXHR
(P < 0.001), and PAEE (P < 0.01) in comparison to the 10kg condition, but showed no
significant difference in the MNHR category. Also, compared to the 15kg condition the
5kg condition registered a significant difference in AHR (P < 0.01), MXHR (P < 0.001),
and PAEE (P < 0.001), but no significant difference in MNHR. Lastly, when considering
the results of the 20kg condition the 5kg condition once again reported a significant
differences in the AHR (P < 0.001), MXHR (P < 0.001), and PAEE (P < 0.001), but
with no significant difference between MNHR values. The 10kg condition showed a
significant difference in MNHR (P < 0.01), AHR (P < 0.05), MXHR (P < 0.05), and
PAEE (P < 0.05) categories compared to that of the 15kg condition. The 10 kg condition
also demonstrated a significant difference in the AHR (P < 0.05), MXHR (P < 0.05), and
PAEE (P < 0.05) categories compared to that of the 20kg condition with no significant
difference in the MNHR values. The final comparison between the 20kg condition and
the 15kg condition revealed only a significant difference in the PAEE (P < 0.05).
35. 29
Chapter 5 -Discussion
The results obtained from this study suggest that a resistance training program
utilizing low to moderate loads with a high number of repetitions performed with more
explosive rates of contraction will yield the highest PAEE. In almost every case, with the
exception of the mean MNHR measurements, the values of the four data categories
demonstrated a decreasing trend as the loading increased. As the load increased, the rate
of contraction decreased. This relationship would suggest that the rate of contraction has
greater influence over PAEE than loading. Despite the total amount of work performed
being the same for each condition, which should theoretically yield the same PAEE, this
was clearly not the case because the PAEE was measured to be significantly different for
each condition compared to all others. We know this occurs due to the considerable
number of variables that influence the PAEE during exercise.
First and foremost, if the total amount of work performed between separate
training protocols is not the same, it will be the protocol that performs the most amount
of work that will have the highest PAEE (Hunter, 2003; Scott, 2011). This is due to the
positive correlation relationship between work and EE. Secondly, it is the muscle-
endurance type exercise protocols, 40-60% 1RM, that will have significantly higher EE
contributions from the different energy systems to include both anaerobic EE, and
possibly even aerobic EE compared to that of muscle-strength, 70+% 1RM, oriented
protocols. This is largely due to the first condition in which a muscle-endurance protocol
36. 30
allows for more work to be performed through the use of a lighter load at a higher
volume compared to that of a heavier load at a lower volume. However, when comparing
the EE contribution from the physiological recovery mechanisms that take place
following both muscle-endurance and muscle-strength oriented protocols, there doesn't
seem to be much of a difference at all. In other words, the amount of recovery EE
following a bout of exercise appears to be very much independent of any contributions
from aerobic EE, anaerobic EE, and even the total amount of work. Given these
consequences, the first place to start when planning an RT program geared towards
weight management would be to include muscle-endurance type exercises due to their
capacity to allow for large amounts of work to be performed and result in a PAEE with
larger contributions from both aerobic and anaerobic energy systems (Scott, 2011).
Beyond utilizing muscle-endurance type exercises to address weight management
through maximizing PAEE, the system by which they are administered my also play an
important role. The results of a study performed by Clark et al. (2010) suggests that the
use of a mixed-interval endurance training protocol will elicit the greatest benefit to
weight management compared to that of circuit resistance training (incorporating
endurance type exercises) and traditional endurance training protocols. The circuit
resistance training protocol proved to have a nearly identical rate of caloric expenditure,
however the mixed-interval method allowed subjects to train within their target HR range
for a longer period of time admitting a greater training effect. It should also be
acknowledged that these results strictly refer to the acute physiological responses and
37. 31
therefore do not express any absolute claim to the outcome of chronic adherence to the
specific exercise regimens (Clark, 2010).
The influence of RME on PAEE is not likely to have changed very much between
each condition of this study. Squat depth most significantly affects the muscular effort of
the knee extensors while the barbell load has more influence over the ankle plantar
flexors. Both depth and loading play a role in the hip extensor RME. Since squat depth
remained constant between conditions, the knee extensor RME would have also been
relatively constant and to a slightly lesser degree the hip extensors as well (Bryanton,
2012). The only varying RME, and therefore PAEE, would come from the ankle plantar
flexors and possibly a small amount from the hip extensors as the loading increased. With
larger muscles expending larger quantities of energy to perform movements, the role of
the hip and knee extensors on influencing PAEE is much larger than the ankle plantar
flexors. Since the RME of these muscle groups remain relatively constant across
conditions, the contribution to the PAEE from RME for each protocol will also remain
relatively constant.
In addition to load-volume influencing the total amount of work being performed
and therefore playing a role in the PAEE, repetition cadence will also require
consideration for the same purpose. Without standardizing the total amount of work to be
performed across all protocols, including range of motion, it will be the fasted repetition
speed that will ultimately accumulate the highest total mass lifted and therefore
performing the most work (Buitrago, 2012). In theory by slowing the repetition speed the
time under tension for the muscles involved is prolonged therefore increasing muscular
38. 32
effort and possibly EE (Westcott, 2001). This would be especially true for the concentric
portion of the lift because it is this portion that is the most costly. However, this has been
proven not to be the case most likely for the previously mentioned factor of total work
performance. On top of that, faster repetition performance is unavoidably coupled with
alternative muscle fiber recruitment (Mazzettie, 2007).
The basis for the higher rates of energy expenditure from the faster contractions,
despite lighter loading, is likely due to the reliance on faster muscle fiber activation
(Ferguson, 2001; Mazzetti, 2007). These muscle fibers compared to smaller slower
muscle fibers have been known to be extremely energy inefficient upon activation (He,
2000; Mazzetti, 2007). The faster contraction rates are likely to invoke a higher ratio of
fast to slow muscle fiber activation resulting in the disproportionate energy expenditure
even under the same loading compared to slow contractions. The reason these faster
contraction rates recruit a larger portion of the energy inefficient fast muscle fibers is
because they are capable of involving higher threshold motor units (Behm, 1993;
Grimbly, 1977; Mazzetti, 2007). On top of that, the higher the threshold of activation that
is required of these motor units, the more fibers they innervate further perpetuating the
inefficiency of energy required to perform the movement (Mazzetti, 2007; Schiaffino,
1970).
The TEE of a RT program, even at high intensities, is easily dwarfed when
compared to that of a prolonged aerobic activity combine with caloric restrictions.
However, RT is known to be responsible for evoking the physiological phenomenon of
EPOC which is capable of remaining above resting levels for up to 48 hours. During this
39. 33
time period numerous energy-requiring processes are taking place in order to restore
homeostatic conditions. Examples of physiological factors being address and corrected
by these energy-requiring processes include heart rate, ventilation rate, body temperature,
oxygen levels in the blood and muscles, adenosine triphosphate and creatine phosphate
replenishment, glycogen re-synthesis, protein synthesis, and more (Abboud, 2013).
Since the degree to which EPOC is elevated above resting levels depends on how
far these physiological factors deviate from normal, trained individuals will be expected
to experience less of an effect from EPOC as opposed to untrained individuals (Hackney,
2008). Considering that all of the participating subjects had a two year minimum of
weightlifting experience and participated in weekly exercise routines that included
squats, caloric expenditure due to EPOC was assumed to be negligible (Abboud, 2013)
(Hackney, 2008). This is due to the training adaptations experienced by fitness trained
individuals that result in a down-regulation of acute energetically costly responses to RT
(Abboud, 2013; Webber, 1993).
Many studies have focused on exercise intensity as the determining factor of
PAEE. Though, intensity can be defined and altered by several methods such as loading
(Hooper, 2013; Naclerio, 2011; Westscott, 2001), number of repetitions (Hooper, 2013;
Naclerio, 2011), speed of contractions (Hooper, 2013; Hunter, 2003; Mazzetti, 2007;
Westcott, 2001), rest intervals (Romero-Arenas, 2013), and repetition cadence (Villagra,
1993; Westcott, 2001). More specifically, exercise intensity could be increased either by
increasing the loading (%1RM) or number of repetitions, using faster contraction speeds,
reducing rest intervals, increasing the eccentric and isometric contraction phase durations
40. 34
of each repetition while shortening the concentric contraction phase, or any combination
of these.
The number of repetitions to achieve muscular failure at 7 ranges of %1RM was
established during a study performed by Naclerio (2011). These %1RM ranges consisted
of 30-40%, >40-50%, >50-60%, >60-70%, >70-80%, >80-90%, and >90%. The
corresponding number of repetitions performed for each range were 46.0 ± 7.4, 34.4 ±
5.9, 26.0 ± 4.2, 18.0 ± 4.2, 13.0 ± 2.6, 7.8 ± 2.1, and 4.7 ± 0.9 respectively. During this
study subjects who had 2-5 years of recreational resistance training performed a bench
press exercise applying maximal force to reach maximal velocity and power during the
concentric phase of the lift (Naclerio, 2011). Given these results, one can better gauge the
intensity of an exercise protocol based on how many repetitions are performed at a
particular %1RM.
A study conducted by Hooper et al. had subjects perform a resistance training
protocol to fatigue while sampling blood lactate and measuring ratings of perceived
exertion using the CR-10 scale. All subjects involved had at least 6 months of RT
experience and were familiar with the exercises involved. The protocol consisted of a
back squat, bench press, and deadlift exercise performed for 10 repetitions at 75%-1RM.
The number of repetition performed was reduced by 1 each set until only 1 repetition
remained allowing for a potential total of 165 repetitions. The protocol elicited a mean
blood lactate value of 14.21 ± 2.19 mmol·L-1
and an average rating of perceived exertion
level of about a 7.5. Each repetition for the protocol was performed as fast as possible
likely playing a crucial role in the results that were yielded given the relationship of
41. 35
contraction speed to EE in addition to the high number of repetitions and loading
(Hooper, 2013).
Hunter et al. (2003) performed a study to compare the energy expenditure of two
different resistance training protocols consisting of a super slow training (SST) protocol
and a traditional training protocol (TT). The exercises selected to be performed in order
for both protocols were leg extension, bench press, biceps curl, leg curl, french curl, bent
row, reverse curl, military press, upright row, and squat. In the SST protocol one set of 8
repetitions at 25% 1RM for each exercise was performed with a 10 second concentric
phase and a 5 second eccentric phase. The TT protocol required two sets of 8 repetitions
for each exercise. Each set was paced to 30 seconds with 60 seconds of rest between sets.
Both the concentric and eccentric portions of each repetition for each exercise were
approximately 1 second in duration. The results of the study showed the TT protocol to
have expended 48% more energy which can be attributed to a multitude of factors. Not
only was the total amount of work higher for the TT protocol, but it utilized a heavier
load being lifted at a faster rate of contraction. This suggests that any number of these
differences between protocols may have some degree of influence over the intensity, and
as a result the PAEE as well (Hunter, 2003).
Given the parameters of this study, the results are very much in support of high
repetitions of fast contraction rates to maximize intensity relative to PAEE. They are less
conclusive in terms of rest intervals due to the fact that only one set of each condition
was completed and the rest between conditions was based on the heart rate recovery of
each subject as opposed to a set interval. There is also little insight on the effects of
42. 36
repetitions cadence in the sense that the isometric portions were always only for a short
pause while the eccentric and concentric portions were always equal to one another.
Increasing the loading by itself will in fact increase the intensity given that it will require
noticeably more effort to perform the same number of repetitions as a lighter load. In the
case that the increase in loading is proportional to the decrease in the number of
repetitions performed, the intensity will in fact be significantly less in terms of the total
PAEE as proven by the result of this study where it was the lightest loading that resulted
in the greatest PAEE.
In summary, although the results of this study reflect the findings of previous
research, it arrived at this conclusion using a more direct strategy by eliminating more
variables which may have ultimately pinpointed the largest contributing variable to
PAEE. Aside from the same amount of work being performed for each condition, it was
performed in the same amount of time, using the same workloads for each subject.
Despite the workloads not being individualized through the use of 1RM percentages, the
quickest contraction speeds still yielded the highest PAEE for each subject. For these
reasons, the mode for maximizing PAEE through the use of a high volume of explosive
repetitions has received further support and confirmation.
Practical Applications
The results of this study in light of similar previous studies suggest that the top
three considerations when designing a weight management oriented RT program may be
43. 37
argued to be the total accumulated mass lifted, the load used to maximize that total, and
the rate of contraction for each repetition. Specifically, maximizing the total accumulated
mass lifted through the use of a low to moderate load with a high number of repetitions
while utilizing maximal rates of contraction. Integrating these features into a mixed-
interval endurance training program may possibly result in an even higher efficiency of
PAEE along with the potential for additional training effects. By incorporating the most
appropriate factors to reach the designated exercise goals, participants will see quicker
results through higher efficiencies and be more likely to adhere to their programs.
This is critical to all professions concerning public health including physicians,
physical therapists, fitness instructors and more and is the key to remedying the obesity
epidemic that plagues such a considerable portion of not only the United States but the
global population as well. A weight management program utilizing this information
would likely prescribe a mixed interval style muscle-endurance RT program (40-60%
1RM depending on experience level) with concentric and eccentric contractions
performed as fast as possible (≤ 1 second). The exercise duration would be based on the
individual’s VO2max and increase as exercise adaptations begin to occur. Total
accumulated mass lifted will be maximized and dictated by prescribing the optimal
combination of loading and exercise durations.
44. 38
Limitations
In spite of the relatively clear cut results gathered from this study, it did have its
share of limitations. One of which would arise from the lack of ability to strictly regulate
the ROM during each repetition, depth in particular. Squat depth was monitored by
simple observation thus the amount of error as a result of this is sensitive to the
perspective of the subjects themselves as well as the study supervisors. Furthermore, the
precision to which each subject was able to follow the rhythm of the metronome for each
protocol was also subject to a certain degree of error. For this reason, the contraction
speed demonstrated between each subject for each protocol is susceptible to the same
degree of error.
Future Studies
Careful thought was invested into developing a study that will yield clean
results with minimal complications; however, additional measures could have been taken
to yield additional feedback. First, albeit contraction speed appears to have proven time
and time again to be the primary contributor to PAEE during RT, including this study,
however it may be supplemented by utilizing an optimal percentage of the individual’s
1RM. Supplemental study to find this optimal percentage or range of percentages of 1RM
may yield even greater potential for PAEE. Other measurements that could be added to
the procedure would be that of oxygen consumption and blood lactate concentrations for
45. 39
a better understanding of how both the aerobic and anaerobic energy systems contribute
to the total PAEE.
Additionally, even though the fastest contraction condition may have yielded the
highest PAEE, its potential impact during practical application is limited by individual
adherence to exercise programs. For this reason, it would be beneficial to take note of the
subjects’ rating of perceived exertion both during and after each exercise condition. The
results of previous studies have shown that exercise intensities above an individual’s
ventilatory threshold demonstrated less positive responses (Kilpatrick, 2007). Muscle
activity levels have also been known to be influenced by their force generation
capabilities. For this reason the addition of EMG recording for the primary muscle groups
involved may provide further insight from the results (Fujita, 2011). Since force
generation can be altered by the load, the contraction rate, or both, the EMG recordings
should provide both quantitative and qualitative information about which of the two
factors, or combination of them, provokes the most muscle activity.
46. 40
REFERENCES
Abboud, George J (07/2013). "Effects of load-volume on EPOC after acute bouts of
resistance training in resistance-trained men". Journal of strength and
conditioning research (1064-8011), 27 (7), p. 1936
DOI: 10.1519/JSC.0b013e3182772eed
Bastien, Marjorie (2014). "Overview of epidemiology and contribution of obesity to
cardiovascular disease". Progress in cardiovascular diseases (0033-0620), 56
(4), p. 369.
DOI: 10.1016/j.pcad.2013.10.016
Behm, D G (01/1993). "Intended rather than actual movement velocity determines
velocity-specific training response". Journal of applied physiology (1985) (8750-
7587), 74 (1), p. 359.
Bryanton, Megan A. (2012). "Effect of squat depth and barbell load on relative muscular
effort in squatting". Journal of strength and conditioning research (1064-8011),
26 (10), p. 2820.
Buitrago, S (07/2012). "Effects of load and training modes on physiological and
metabolic responses in resistance exercise". European journal of applied
physiology (1439-6319), 112 (7), p. 2739.
DOI: 10.1007/s00421-011-2249-9
47. 41
Buitrago, Sebastian (04/2013). "Mechanical load and physiological responses of four
different resistance training methods in bench press exercise". Journal of strength
and conditioning research (1064-8011), 27 (4), p. 1091.
DOI: 10.1519/JSC.0b013e318260ec77
Butte, N F (01/2012). "Assessing physical activity using wearable monitors: measures of
physical activity". Medicine and science in sports and exercise (0195-9131), 44 (1
suppl 1), p. S5.
DOI: 10.1249/MSS.0b013e3182399c0e
Clark, J E (08/2010). "Examining matched acute physiological responses to various
modes of exercise in individuals who are overweight". Journal of strength and
conditioning research (1064-8011), 24 (8), p. 2239.
DOI: 10.1519/JSC.0b013e3181ce245c
Cotter, Jashua (07/2013). “Knee joint kinetics in relation to commonly prescribed squat
loads and depths”. Journal of strength and conditioning research (1064-8011), 27
(7), p. 1765
DOI: 10.1519/JSC.0b013e3182773319
Ferguson, R A (2001). "Muscle oxygen uptake and energy turnover during dynamic
exercise at different contraction frequencies in humans". The Journal of
physiology (0022-3751), 536, p. 261.
DOI: 10.1111/j.1469-7793.2001.00261.x
48. 42
Fujita, Eiji (12/2011). "Association between knee extensor strength and EMG activities
during squat movement". Medicine and science in sports and exercise (0195-
9131), 43 (12), p. 2328.
DOI: 10.1249/MSS.0b013e3182207ed8
Gastinger, Steven (2012). "Energy expenditure estimate by heart-rate monitor and a
portable electromagnetic-coil system". International journal of sport nutrition and
exercise metabolism (1526-484X), 22 (2), p. 117
Grimby, L (01/1977). "Firing rate and recruitment order of toe extensor motor units in
different modes of voluntary conraction". The Journal of physiology (0022-3751),
264 (3), p. 865.
DOI: 10.1016/S0006-3495(00)76349-1
Hackney, K J (09/2008). "Resting energy expenditure and delayed-onset muscle soreness
after full-body resistance training with an eccentric concentration". Journal of
strength and conditioning research (1064-8011), 22 (5), p. 1602
DOI: 10.1519/JSC.0b013e31818222c5
He, Z H (08/2000). "ATP consumption and efficiency of human single muscle fibers with
different myosin isoform composition". Biophysical journal (0006-3495), 79
(2), p. 94513
DOI: 10.1016/S0006-3495(00)76349-1
49. 43
Hooper, David R. (01/2013). "Effects of resistance training fatigue on joint
biomechanics". Journal of strength and conditioning research (1064-8011), 27
(1), p. 146
DOI: 10.1519/JSC.0b013e31825390da
Hunter, G R (02/2003). "Comparison of metabolic and heart rate responses to super slow
vs. traditional resistance training". Journal of strength and conditioning research
(1064-8011), 17 (1), p. 76.
Keiner, Michael (2013). “Strength performance in youth: trainability of adolescents and
children in the back and front squats”. Journal of strength and conditioning
research (1064-8011), 27 (2), p. 357-362
DOI: 10.1519/JSC.0b013e3182576fbf
Kilpatrick, M (08/2007). "Affective responses to exercise are dependent on intensity
rather than total work". Medicine and science in sports and exercise (0195-9131),
39 (8), p. 1417.
DOI: 10.1249/mss.0b013e31806ad73c
List, Renate (06/2013). “Kinematics of the trunk and the lower extremities during
restricted and unrestricted squat”. Journal of strength and conditioning research
(1064-8011), 27 (6), p.1529
DOI: 10.1519/JSC.0b013e3182736034
50. 44
Mazzetti, Scott (08/2007). "Effect of explosive versus slow contractions and exercise
intensity on energy expenditure". Medicine and science in sports and exercise
(0195-9131), 39 (8), p. 1291.
DOI: 10.1249/mss.0b013e318058a603
Menez, S (12/2013). "Perspectives on obesity and its treatment: health care providers and
the general public in rural West Virginia and urban Baltimore". Health education
& behavior (1090-1981), 40 (6), p. 663.
DOI: 10.1177/1090198112473101
Naclerio, Fernando (07/2011). "Control of resistance training intensity by the OMNI
perceived exertion scale". Journal of strength and conditioning research (1064-
8011), 25 (7), p. 1879.
DOI: 10.1519/JSC.0b013e3181e501e9
Robergs, Robert A. (02/2007). “Energy expenditure during bench press and squat
exercises". Journal of strength and conditioning research (1064-8011), 21 (1), p.
123.
DOI: 10.1519/00124278-200702000-00023
Romero-Arenas, S (03/2013). "Effects of high-resistance circuit training in an elderly
population". Experimental gerontology (0531-5565), 48 (3), p. 334
DOI: 10.1016/j.exger.2013.01.007
Schiaffino, S (10/1970). “Relations between structure and function in rat skeletal muscle
fibers". The Journal of cell biology (0021-9525), 47 (1), p. 107.
51. 45
DOI: 10.1083/jcb.47.1.107
Scott, Christopher B (04/2011). "Aerobic, anaerobic, and excess postexercise oxygen
consumption energy expenditure of muscular endurance and strength: 1-set of
bench press to muscular fatigue". Journal of strength and conditioning research
(1064- 8011), 25 (4), p. 903.
DOI: 10.1519/JSC.0b013e3181c6a128
Villagra, F (1993). "Metabolic cost and efficiency in 2 forms of squatting exercise in
children and adults". European journal of applied physiology and occupational
physiology (0301-5548), 67 (6), p. 549.
DOI: 10.1007/BF00241653
Webber, J (04/1993). "Metabolic actions of catecholamines in man". Baillière's clinical
endocrinology and metabolism (0950-351X), 7 (2), p. 393
DOI: 10.1016/S0950-351X(05)80181-8
Westcott, WL (2001). "Effects of regular and slow speed resistance training on muscle
strength". Journal of sports medicine and physical fitness (0022-4707), 41 (2), p.
154.
52. ACADEMIC VITA
Samuel T. Barrett
615 School Lane
Wallingford, PA 19086
Stbarrett99@gmail.com
________________________________________
EDUCATION:
The Pennsylvania State University, State College, PA
Bachelor of Science in Kinesiology, May 2014
Honors in Kinesiology
Thesis Supervisor: Dr. Jinger Gottschall
AWARDS:
The President's Freshman Award
The President Sparks Award
The Even Pugh Scholar Award (Junior)
The Even Pugh Scholar Award (Senior)
Abby Sutherland Scholarship
ASSOCIATION MEMBERSHIPS/ACTIVITIES:
National Society of Collegiate Scholars Member
Penn State Powerlifting Club Member
PROFESSIONAL EXPERIENCE:
Motion Analysis Laboratory- Assistant
Supervisor: Riley Sheehan
Spring 2013
Fitness Together, Summer- Intern
Supervisor: Bruce Kelly
Summer 2012
Excel Physical Therapy- Volunteer
Supervisor: Gregory Masiko
Summer 2013
Optimum Physical Therapy- Volunteer
Supervisor: Jessica Laniak
Summer 2013