This study examined the effects of self myofascial release (SMR) on lower limb power performance and whether body composition affects these effects. Fifteen participants performed countermovement jumps before and after SMR on key muscle groups. Peak force, power, and rate of force development were measured. Body composition was analyzed via DXA scan. Only peak rate of force development increased significantly following SMR. Significant negative correlations were found between changes in peak force, power, and rate of force development and leg segment mass and lean mass. This suggests SMR may not benefit power for individuals with larger leg mass and lean mass but could improve range of motion or be appropriate for those where absolute power is not a priority or below a muscle pressure threshold.
The effects of post-activation potentiation on rate of force development in N...Patrick Peterson
The purpose of this study is t to quantify the changes in early (t < 0.1s) and late phase (t < 0.1s) rate of force development as a result of post- activation potentiation. The phenomenon in which the force exerted by a muscle is increased following a previous contraction is known as post-activation potentiation (PAP) (Robbins, 2005). Two proposed mechanisms of PAP are an improved contractile environment and a neuromuscular response to potentiation. The first of which is a local response. Increased sensitivity of actin-myosin to calcium due to the phosphorylation of myosin regulatory light chains (R-LC) (Vandenboom, 1995). The second proposed mechanism is a systemic response of the nervous system. Recent studies have proposed that increased recruitment of higher order motor units result in the increase in force of subsequent muscle contractions (Tillin, 2009). The rate at which contractile force is produced following the onset of muscle contraction is commonly referred to as rate of force development (RFD) (Andersen, 2009). RFD can be divided into early (t < 0.1s) and late phase (t < 0.1s) (de Oliveria et al., 2013). Early phase RFD is primarily influenced by the central nervous system response to the stimulus whilst the late phase is influenced by contractile force and muscle cross sectional area (Aagaard, 2002). For this study a sample size 20 NCAA Division I athletes comprising of 10 males and 10 females performed two explosive plyometric exercises on a force plate to gather a baseline reading. Then a heavy resistance exercise (80% 1RM) that mimicked the same motor pattern of the corresponding plyometric was performed prior to the second test to elicit PAP. Differences in early and late- phase RFD pre- and post- intervention were then analyzed using Pearson’s correlation coefficient (r). Both groups showed statistically significant improvements in both the inertial vertical jump (VJ) and inertial standing broad jump (BJ) following the conditioning stimulus (p = 0.05). The greatest differences were seen in early- phase RFD of both plyometric exercises. The greatest of which occurred in the VJ following a barbell back squat (r = 0.78)(p = 0.01). No statistically significant differences were observed in late- phase RFD under either condition. These findings would suggest that changes in RFD due to PAP are a result of a systemic response of the central nervous system.
Comparative Study on Physical Fitness of Volleyball and Football Players in U...iosrjce
Background: Physical fitness is an essential first and foremost criterion in every game. Without having physical
fitness no one can elicit his amble performance level. Therefore it is essential to investigate that in which game
among Volleyball and Football, the level of physical fitness is more essential. Aim: The purpose of this study
was to investigate the level of physical fitness of volleyball player and football player in university level.
Methodology: For the present study 15 male volleyball players and 15 male football players were selected
randomly and they had participated in university competition in 2004 from Jadavpur University. Age group of
the subjects was 18-24 years. To find out the physical fitness APHERED Youth Physical Fitness Test were
conducted. Statistics: For comparison of various physical fitness components of volley ball players and football
player independent t-test has done and level of significance has verified at 0.05 levels. Result: Finding reveals
that muscular strength of football player (5.33 times/min. pull ups) was higher than volley ball player (4.87
times/min. pull ups), the muscular endurance of football player (39.86 times sit ups) was higher than volleyball
player (38.73 times sit ups), agility of football player (19.32 sec.) was higher than volleyball player (19.78 sec.),
explosive leg strength of football player (6.90 mts.) was higher than volleyball player (6.78 mts.), Speed of
football player (6.70 sec.) was higher than volley ball player (6.99 sec.) and also cardiovascular endurance of
football player (1.82 min.) was higher than volleyball player (1.82 min.) but the difference in agility and speed
were significant at 0.05 level. Conclusion: The physical fitness of football player was higher than the volleyball
player.
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.
The Effects Of Creatine On Repeated Sprint Performance, Maximum Strength And ...Carl Page
Working as part of a research team investigating the effects of creatine on repeated sprint performance, maximum strength and power.
The nutritional supplement creatine has been gaining popularity exponentially over the past decade, so much so, that it is one of the most widely used Ergogenic aids. Theoretically, an increase in creatine stores within the muscle may enhance the rate of ATP synthesis and PCr resynthesis during high-intensity exercise, and therefore, improve performance. However, within the scientific literature the effects of creatine on exercise performance remain equivocal.
Bibliografia periodizzazione nell’allenamento della forza rapida. Sds Scuola dello Sport 73/74
Klaus Wirth, Dietmar Schmidtbleicher
http://www.calzetti-mariucci.it/shop/categorie/rivista-sds-scuola-dello-sport
Body composition assessment of english premier leagueFernando Farias
The measurement of body composition is now a fun-
damental component of sport science support in elite-
level soccer. Indeed, regular assessments of body com-
position are often used to determine suitability for
competition as well as to monitor the effectiveness of
dietary and training interventions (Sutton, Scott,
Wallace, & Reilly, 2009).
The effects of post-activation potentiation on rate of force development in N...Patrick Peterson
The purpose of this study is t to quantify the changes in early (t < 0.1s) and late phase (t < 0.1s) rate of force development as a result of post- activation potentiation. The phenomenon in which the force exerted by a muscle is increased following a previous contraction is known as post-activation potentiation (PAP) (Robbins, 2005). Two proposed mechanisms of PAP are an improved contractile environment and a neuromuscular response to potentiation. The first of which is a local response. Increased sensitivity of actin-myosin to calcium due to the phosphorylation of myosin regulatory light chains (R-LC) (Vandenboom, 1995). The second proposed mechanism is a systemic response of the nervous system. Recent studies have proposed that increased recruitment of higher order motor units result in the increase in force of subsequent muscle contractions (Tillin, 2009). The rate at which contractile force is produced following the onset of muscle contraction is commonly referred to as rate of force development (RFD) (Andersen, 2009). RFD can be divided into early (t < 0.1s) and late phase (t < 0.1s) (de Oliveria et al., 2013). Early phase RFD is primarily influenced by the central nervous system response to the stimulus whilst the late phase is influenced by contractile force and muscle cross sectional area (Aagaard, 2002). For this study a sample size 20 NCAA Division I athletes comprising of 10 males and 10 females performed two explosive plyometric exercises on a force plate to gather a baseline reading. Then a heavy resistance exercise (80% 1RM) that mimicked the same motor pattern of the corresponding plyometric was performed prior to the second test to elicit PAP. Differences in early and late- phase RFD pre- and post- intervention were then analyzed using Pearson’s correlation coefficient (r). Both groups showed statistically significant improvements in both the inertial vertical jump (VJ) and inertial standing broad jump (BJ) following the conditioning stimulus (p = 0.05). The greatest differences were seen in early- phase RFD of both plyometric exercises. The greatest of which occurred in the VJ following a barbell back squat (r = 0.78)(p = 0.01). No statistically significant differences were observed in late- phase RFD under either condition. These findings would suggest that changes in RFD due to PAP are a result of a systemic response of the central nervous system.
Comparative Study on Physical Fitness of Volleyball and Football Players in U...iosrjce
Background: Physical fitness is an essential first and foremost criterion in every game. Without having physical
fitness no one can elicit his amble performance level. Therefore it is essential to investigate that in which game
among Volleyball and Football, the level of physical fitness is more essential. Aim: The purpose of this study
was to investigate the level of physical fitness of volleyball player and football player in university level.
Methodology: For the present study 15 male volleyball players and 15 male football players were selected
randomly and they had participated in university competition in 2004 from Jadavpur University. Age group of
the subjects was 18-24 years. To find out the physical fitness APHERED Youth Physical Fitness Test were
conducted. Statistics: For comparison of various physical fitness components of volley ball players and football
player independent t-test has done and level of significance has verified at 0.05 levels. Result: Finding reveals
that muscular strength of football player (5.33 times/min. pull ups) was higher than volley ball player (4.87
times/min. pull ups), the muscular endurance of football player (39.86 times sit ups) was higher than volleyball
player (38.73 times sit ups), agility of football player (19.32 sec.) was higher than volleyball player (19.78 sec.),
explosive leg strength of football player (6.90 mts.) was higher than volleyball player (6.78 mts.), Speed of
football player (6.70 sec.) was higher than volley ball player (6.99 sec.) and also cardiovascular endurance of
football player (1.82 min.) was higher than volleyball player (1.82 min.) but the difference in agility and speed
were significant at 0.05 level. Conclusion: The physical fitness of football player was higher than the volleyball
player.
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.
The Effects Of Creatine On Repeated Sprint Performance, Maximum Strength And ...Carl Page
Working as part of a research team investigating the effects of creatine on repeated sprint performance, maximum strength and power.
The nutritional supplement creatine has been gaining popularity exponentially over the past decade, so much so, that it is one of the most widely used Ergogenic aids. Theoretically, an increase in creatine stores within the muscle may enhance the rate of ATP synthesis and PCr resynthesis during high-intensity exercise, and therefore, improve performance. However, within the scientific literature the effects of creatine on exercise performance remain equivocal.
Bibliografia periodizzazione nell’allenamento della forza rapida. Sds Scuola dello Sport 73/74
Klaus Wirth, Dietmar Schmidtbleicher
http://www.calzetti-mariucci.it/shop/categorie/rivista-sds-scuola-dello-sport
Body composition assessment of english premier leagueFernando Farias
The measurement of body composition is now a fun-
damental component of sport science support in elite-
level soccer. Indeed, regular assessments of body com-
position are often used to determine suitability for
competition as well as to monitor the effectiveness of
dietary and training interventions (Sutton, Scott,
Wallace, & Reilly, 2009).
The Challenges of Sarcopenia: Definition, Underlying Mechanisms, Intervention...InsideScientific
During this webinar, Drs. Peterson and Guralnik will discuss sarcopenia, the physiological mechanisms underlying the disease, and the current avenues of treatment and assessment that are being researched and developed for patients.
Sarcopenia is the age-related loss of muscle that causes decreased strength and functional limitations. Muscle loss occurs universally in people as we age, but some people lose muscle at an accelerated rate compared to others. While chronic disease can cause sarcopenia, it can also result from a sedentary lifestyle, hospitalizations and extended bed rest due to other conditions.
A gradual decline in muscle mass and strength begins around 30 years of age with this condition, and annual losses get larger throughout life. The self-reporting of functional difficulties to health care providers may give an indication that sarcopenia is present, but a more precise definition is needed for research and clinical use.
Efforts made in Europe and the US have used grip strength, gait speed and lean mass to define sarcopenia, but these definitions lead to large differences in prevalence rate and discordance in who is labelled as “sarcopenic”. To assess this condition, lean mass as measured by dual x-ray absorptiometry (DXA) may not accurately reflect actual muscle mass, but a new technique using dilution of deuterium-labelled creatine may prove to be superior in clinically diagnosing sarcopenia. Currently, a consensus has not been reached on the clinical outcome assessments that can be used by regulatory agencies to judge the effectiveness of drugs for sarcopenia.
A number of potential interventions are being explored to treat sarcopenia in older people, but no drugs are currently approved for this condition. The antidiabetic drug metformin shows promise in preventing many age-associated conditions, but appears to blunt the benefits of exercise on muscle. Senolytic drugs, which clear senescent cells, may improve muscle repair following injury preferentially in older individuals.
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
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.
A comparison of 2 circuit exercise training techniques
BASES Presentation
1. www.derby.ac.uk
Self Myofascial Release (SMR) is commonly used as a warm up
modality due to the positive effects on range of motion (ROM),
although the acute effects on athletic performance are not fully
understood. Research has demonstrated significant reduction
(Janot, Malin, Cook, Hagenbucher, Draeger, Jordan, Quinn, 2014),
increase (Peacock, Krein, Silver, Sanders & von Carlowitz, 2014)
and no change (Healey, Hatfield, Blanpied, Dorfman, Riebe, 2014)
in peak power following an SMR protocol. No potential
mechanism for these differences has been explored in the
current literature. Therefore the purpose of this study was to
develop an understanding if a relationship exists between body
composition and the effects of an SMR intervention on lower limb
power performance (LLPP).
Fifteen participants (Table 1) were required to complete 3
Counter Movement Jumps (CMJ) on a force plate (400 Series
Force Plate, Fitech, Skye, Australia) both with and without SMR. An
SMR Procedure was completed for a minute per muscle group
(table 2) immediately prior to measurements of CMJ.
Mean values for the 3 CMJ were used to calculate Peak Force (PF),
Peak Power (PP), Peak Rate of Force Development (PRFD) and
Jump Height. Body composition was analysed using a Dual-
Energy X-Ray Absorptiometry (DXA), Leg Segment Mass (LSM),
Segment Body Fat % (LSBF) and Leg Segment Lean Mass (LSLM)
were obtained from each scan.
Table 1 Anthropometric characteristics
Table 2 Musculature targeted by SMR.
Figure 1 Start point of CMJ Figure 2 SMR of Peroneals
Does Body Composition affect Self Myofascial Release’s effect
on lower limb power?
Cooke, K. , Keenan, J.
University of Derby, College of Life and Natural Sciences, Derby, DE22 1BG
Introduction
Method
Only PRFD was significantly higher following SMR t(14)=-2.182,
P=0.047, no other significant results were found between
experimental conditions.
Significant negative correlations were however observed between
changes in PF, PP and PRFD and LSM (figures 3-5) and PF and PP
and LSLM (figures 6 & 7), no other significant correlations were
found between experimental conditions although LSBF & PF was
approaching a significant positive correlation (R=0.494, P=0.061)
(see figure 8).
Age
(years)
Mass (kg)
Height
(cm)
LSM
(kg)
LSLM
(kg)
LSBF
(%)
Male
(n=9)
22.31
±1.59
79.78
±10.94
178.88
±6.13
27.74
±4.23
21.13
±2.66
17.03
±5.98
Female
(n=6)
23.73
±2.89
64.00
±7.84
168.20
±4.42
23.40
±3.47
15.40
±2.64
33.15
±5.98
Gastrocnemius Illiotibial Band Adductors Gluteus Maximus
Soleus/Achilles
Tendon
Rectus Femoris Vastus Medialis
TFL/ Anterior
Gluteus Medius/
Gluteus Minimus
Peroneals Vastus Lateralis Piriformis
Acknowledgements
Summary & Conclusion
Results
References
There are observed differences within the participant group for
the change in PP, PF, & PRFD dependent upon LSM & LSLM. This
study suggests that SMR as a warm up must be administered with
care, as it may not always be appropriate for individuals with
large LSM and LSLM who are requiring peak LLPP. However SMR
may be an appropriate warm up for individuals with low LSM and
LSLM who are requiring an improvement in ROM or for
individuals where absolute PP is not the main priority. Further
research should look to investigate at which point performance
and ROM are affected by a threshold pressure through the
musculature.
To my supervisor James Keenan, not only for continued support and
guidance but for your patience! Also to my friends and family who are
consistently excellent.
Healey, K., Hatfield, D., Planpied, P., Dorfman, L., & Riebe, D. (2014). The Effects of Foam Rolling on Myofascial
Release and Performance. The Journal of Strength and Conditioning Research, 30-31.
Janot, J., Malin, B., Cook, R., Hagenbucher, J., Draeger, A., Jordan, M., Quinn,E. (2013). Effects of Self Myofascial
Release and Static Stretching on Anaerobic Power Output. Journal of Fitness Research, 41-54.
Peacock, C. A., Krein, D. D., Silver, T. A., Sanders, G. J., & von Carlowitz, K.-P. A. (2014). An Acute bout of Self
Myofascial Release in the form of Foam Rolling impoves performance testing. International Journal of Exercise
Science, 202-211.
