This study tested whether applying a scientifically based nutritional strategy rather than a freely chosen strategy could improve marathon performance in non-elite runners. Runners were divided into two groups - one that chose their own nutrition and one following a targeted intake of fluids, carbohydrates, sodium, and caffeine. Those following the scientific strategy completed the marathon on average 10 minutes and 55 seconds faster, representing a 4.7% improvement. Both groups experienced low levels of gastrointestinal symptoms, with no significant differences between groups. The results suggest that a scientific nutritional approach can enhance marathon performance for recreational runners compared to allowing them to choose their own intake.
This document presents an analysis of different training plans for collegiate distance runners to optimize performance. It reviews literature on physiological determinants of running performance, including maximal oxygen uptake (VO2 max), running economy, and lactate threshold. Studies show high-intensity interval training is most effective for improving VO2 max, while both high-intensity and high-volume plans can improve running economy. The document concludes that an optimal plan would emphasize high-intensity workouts to enhance VO2 max and include strength training and long runs to aid running economy and lactate threshold.
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.
Anthropometric determinants of rowing ergometer performance in physically ina...Fernando Maria Saura
This document summarizes a study that evaluated anthropometric characteristics as determinants of 500 m rowing ergometer performance in physically inactive college females. The study involved 196 college females aged 19-23 years who were measured for various anthropometric parameters including body mass, height, limb lengths, and indices. Participants then performed a 500 m maximal effort trial on a rowing ergometer. Stepwise multiple regression analysis revealed that body mass, height, limb lengths, BMI, slenderness index, and Choszcz-Podstawski index were statistically significant determinants of performance. The best results were seen in females with heights of 170-180 cm and limb lengths of 75-80 cm and 85-90 cm.
Familiarization, reliability, and evaluation of a multiple sprint running tes...Pablo Vicencio Ardiles
This study investigated the use of self-selected recovery periods in a multiple sprint test to reliably quantify an individual's ability to resist fatigue. Twenty active students completed 4 trials of 12 x 30m sprints with self-selected recovery between sprints. The results showed learning effects in the first 2 trials as evidenced by more subjects failing to maintain sprint performance. Reliability was good between trials 3 and 4, with a coefficient of variation of 11.1% and intraclass correlation of 0.76. Perceived exertion increased progressively throughout trials despite no change in sprint times. Aerobic fitness showed little correlation with mean recovery time.
Impact of Yogic Exercise on Body Fat Percentage on Middle Aged Obese PeopleSports Journal
Purpose: The Purpose of the study was to find out the effect of yogic exercises on body fat percentage of middle aged obese people.
Selection of Subjects: For the present study 20 male obese people from locality of Bilaspur were selected randomly as the subjects for the study. The age of the subjects ranged between 40-50 years.
Selection of Variables: The variables selected for the present study were yogic training (independent variable), body fat percentage (dependent variable).
Methodology: For the study pretest – post-test randomized group design, which consists of control group (10 subjects) and experimental group (10 subjects) were used. The data were collected through the pretest, before training and post-test, after six weeks of yogic exercises training.
Statistical Technique: For comparing pre and post-test means of experimental and control groups, descriptive analysis and Analysis of Co-Variance (ANCOVA) were used and the level of significance was set at 0.05 level of confidence.
Result: The result of the study showed that there was insignificant difference between pre and post-test (experimental group) of body fat percentage.
This document summarizes a study that compared lipid oxidation and perceived exertion levels during different types of exercise in obese individuals. Ten obese men performed three 45-minute exercises: continuous exercise at the fat max intensity, and two intermittent exercises that alternated between intensities above and below the fat max. While total energy expenditure was highest with continuous exercise, the amount of fat oxidized was equivalent across all exercises. Perceived exertion as measured by the Borg scale was lower for the intermittent exercises compared to continuous exercise. The study concludes that intermittent exercise is less strenuous but similarly effective for fat oxidation in obese individuals compared to continuous exercise.
This document summarizes research on the effects of high-intensity interval training (HIIT) on obesity. It finds that HIIT can be an effective strategy for promoting health in sedentary overweight or obese individuals. Specifically, several studies have found that HIIT can increase fat oxidation, improve insulin sensitivity, and reduce waist circumference and blood pressure in this population. Both interval training protocols based on the Wingate test and modified low-volume HIIT programs have led to metabolic benefits. While more research is still needed, HIIT shows promise as a time-efficient exercise strategy to induce beneficial adaptations for weight loss and health in overweight and obese individuals.
This document presents an analysis of different training plans for collegiate distance runners to optimize performance. It reviews literature on physiological determinants of running performance, including maximal oxygen uptake (VO2 max), running economy, and lactate threshold. Studies show high-intensity interval training is most effective for improving VO2 max, while both high-intensity and high-volume plans can improve running economy. The document concludes that an optimal plan would emphasize high-intensity workouts to enhance VO2 max and include strength training and long runs to aid running economy and lactate threshold.
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.
Anthropometric determinants of rowing ergometer performance in physically ina...Fernando Maria Saura
This document summarizes a study that evaluated anthropometric characteristics as determinants of 500 m rowing ergometer performance in physically inactive college females. The study involved 196 college females aged 19-23 years who were measured for various anthropometric parameters including body mass, height, limb lengths, and indices. Participants then performed a 500 m maximal effort trial on a rowing ergometer. Stepwise multiple regression analysis revealed that body mass, height, limb lengths, BMI, slenderness index, and Choszcz-Podstawski index were statistically significant determinants of performance. The best results were seen in females with heights of 170-180 cm and limb lengths of 75-80 cm and 85-90 cm.
Familiarization, reliability, and evaluation of a multiple sprint running tes...Pablo Vicencio Ardiles
This study investigated the use of self-selected recovery periods in a multiple sprint test to reliably quantify an individual's ability to resist fatigue. Twenty active students completed 4 trials of 12 x 30m sprints with self-selected recovery between sprints. The results showed learning effects in the first 2 trials as evidenced by more subjects failing to maintain sprint performance. Reliability was good between trials 3 and 4, with a coefficient of variation of 11.1% and intraclass correlation of 0.76. Perceived exertion increased progressively throughout trials despite no change in sprint times. Aerobic fitness showed little correlation with mean recovery time.
Impact of Yogic Exercise on Body Fat Percentage on Middle Aged Obese PeopleSports Journal
Purpose: The Purpose of the study was to find out the effect of yogic exercises on body fat percentage of middle aged obese people.
Selection of Subjects: For the present study 20 male obese people from locality of Bilaspur were selected randomly as the subjects for the study. The age of the subjects ranged between 40-50 years.
Selection of Variables: The variables selected for the present study were yogic training (independent variable), body fat percentage (dependent variable).
Methodology: For the study pretest – post-test randomized group design, which consists of control group (10 subjects) and experimental group (10 subjects) were used. The data were collected through the pretest, before training and post-test, after six weeks of yogic exercises training.
Statistical Technique: For comparing pre and post-test means of experimental and control groups, descriptive analysis and Analysis of Co-Variance (ANCOVA) were used and the level of significance was set at 0.05 level of confidence.
Result: The result of the study showed that there was insignificant difference between pre and post-test (experimental group) of body fat percentage.
This document summarizes a study that compared lipid oxidation and perceived exertion levels during different types of exercise in obese individuals. Ten obese men performed three 45-minute exercises: continuous exercise at the fat max intensity, and two intermittent exercises that alternated between intensities above and below the fat max. While total energy expenditure was highest with continuous exercise, the amount of fat oxidized was equivalent across all exercises. Perceived exertion as measured by the Borg scale was lower for the intermittent exercises compared to continuous exercise. The study concludes that intermittent exercise is less strenuous but similarly effective for fat oxidation in obese individuals compared to continuous exercise.
This document summarizes research on the effects of high-intensity interval training (HIIT) on obesity. It finds that HIIT can be an effective strategy for promoting health in sedentary overweight or obese individuals. Specifically, several studies have found that HIIT can increase fat oxidation, improve insulin sensitivity, and reduce waist circumference and blood pressure in this population. Both interval training protocols based on the Wingate test and modified low-volume HIIT programs have led to metabolic benefits. While more research is still needed, HIIT shows promise as a time-efficient exercise strategy to induce beneficial adaptations for weight loss and health in overweight and obese individuals.
The document examines the effects of a 60-minute moderate intensity spinning class on total body water (TBW) levels in 14 subjects. Bioelectrical impedance analysis was used to measure subjects' pre- and post-exercise TBW. Results showed no significant change in TBW after the spinning class, indicating that moderate intensity spinning does not affect TBW levels.
Glucose and homeostasis model assessment of insulin resistanceMasoumeh Hosseini
This study examined the acute effects of a single moderate-intensity aerobic exercise session on markers of type 2 diabetes in male smokers. Fifteen sedentary male smokers underwent a 40-minute run and had blood samples taken pre- and post-exercise to measure glucose, insulin, and insulin resistance levels. The study found that glucose concentration, serum insulin levels, and insulin resistance decreased significantly following the single exercise session. This suggests that even short-term moderate exercise can positively influence indicators of type 2 diabetes in smokers.
This study aims at exploring the eff ect of a 4-week hypoxic training on some physiological and biochemical parameters in the 400-m competing athletes of the Palestinian athletics team. Twelve trained male athletes were divided into two groups, normoxic training (n = 6) and hypoxic training (n = 6) for residing at sea-level.The training period was 90min, 3 days per week for 4 weeks.Therefore,physiological measurements showed (Vital Capacity (VC), Maximal Oxygen Consumption (VO2max) and Heart-Rate (HR)); Biochemical measurements (Erythropoietin (EPO), Hemoglobin (Hb), Hematocrit (Hct) and Partial Oxygen Pressure PO2); the numerical level of running 400m.
Abstract
Background and purpose: Diet and muscle fiber type are all major factors in predicting intramuscular carnosine concentration [1]. Constituent substrate availability, including the amino acids L-histidine and more specifically beta alanine, play the greatest role in determining the concentration of intramuscular carnosine, a potent intracellular Hydrogen ion buffer. The purpose of this review is to analyze the efficacy of beta alanine supplementation on exercise performance, specifically activities relying on anaerobic glycolysis.
Method: The review included articles from peer-reviewed journals with sufficient data related to the purpose and focus of the study. Inclusion criteria included randomized control trials, systematic reviews and meta-analysis published since 2007.
Results: Twenty relevant studies were identified; various experimental protocols were employed, including both acute and chronic effects of beta alanine supplementation on physical performance. All studies were published 2007 through 2017, providing a robust overview of experimentation over the last 10 years.
Discussion and conclusion: Among studies analyzed in this mini-review, the consensus reached regarding the efficacy of beta alanine supplementation for performance enhancement was relatively positive. Most studies followed similar supplementary strategies, consuming anywhere from 1.6 to 6.4g/day for 2 to 10 weeks. The majority of these studies demonstrated statistically significant increases in intramuscular carnosine content, a physiological parameter that is positively correlated with sprinting and power performance. Many studies presented results in support of enhanced muscular endurance performance subsequent to supplementation relative to the placebo group. Researchers also noted a decline in peak aerobic capacity concurrent to a delay in the onset of blood lactate accumulation, supporting the notion of enhanced glycolytic capacity. More research is necessary to identify optimal dosing strategies for performance optimization across the spectrum of physical activities.
- A meta-analysis of 16 studies found that rinsing the mouth with a carbohydrate solution during endurance exercise has a small but statistically significant effect of improving performance compared to a placebo.
- The overall effect size was 0.28, indicating a small performance benefit from carbohydrate mouth rinsing. Higher carbohydrate concentrations in the mouth rinse resulted in better performance.
- Study characteristics like exercise mode, pre-exercise diet, and type of carbohydrate did not significantly affect the results of the meta-analysis.
Match analysis studies
have also demonstrated that football requires
participants to repeatedly produce maximal or
nearmaximal actions of short durationwith brief
recovery periods [40,45]. For these reasons, foot-
ball training should commonly include physical
exercises aimed to enhance both aerobic fitness
and repeated-sprint ability (RSA).
Beetroot juice supplementation and its effect on 1Kody Springsteen
1. The study aimed to examine the effects of beetroot juice supplementation on 1-mile time trial performance. Ten moderately active subjects (6 male, 4 female) completed 1-mile time trials after consuming either beetroot juice or a placebo drink.
2. Results showed no significant differences in 1-mile time trial times between the beetroot juice and placebo trials for males or females. Time differences between trials for each subject ranged from an improvement of 5 seconds to a decline of 5 seconds.
3. The study found that a single dose of beetroot juice did not significantly improve 1-mile run time trial performance in moderately active males or females, as the p-values for both groups were greater than 0.
IOSR Journal of Humanities and Social Science is an International Journal edited by International Organization of Scientific Research (IOSR).The Journal provides a common forum where all aspects of humanities and social sciences are presented. IOSR-JHSS publishes original papers, review papers, conceptual framework, analytical and simulation models, case studies, empirical research, technical notes etc.
- The document examines the prospective associations between objectively measured physical activity, sedentary time, cardiorespiratory fitness, and cardiometabolic risk factors over 4 years in people with type 2 diabetes.
- It finds that increases in physical activity energy expenditure and cardiorespiratory fitness, and decreases in sedentary time, were associated with improvements in waist circumference, blood pressure, and clustered cardiometabolic risk.
- Baseline measures of these factors were generally not predictive of cardiometabolic risk at the 4-year follow up, suggesting the importance of changes over time rather than single measures.
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.
K. Sletten - Performance enhancing effects of nitrate related supplementsKristian Sletten
This extended paper systematically reviewed 23 studies on the effects of nitric oxide (NO)-related supplementation on aerobic performance in healthy humans. The studies showed that NO supplementation, in the form of beetroot, arginine, citrulline or pharmacological NO substances, can improve exercise performance by increasing time to exhaustion and lowering submaximal oxygen consumption. The ergogenic effects appeared to be more consistent for untrained individuals and with high-intensity exercise. While NO supplements may enhance aerobic performance, the size of the effect depends on training status, exercise type, and supplementation regimen.
Objective to analyze the mechanism and effect of chromium on the recovery of bodybuilding. By consulting the data, the experimental. analysis method was adopted. The results of research practice show that the comparison of relevant indicators among people who exercise regularly shows that people who exercise regularly have a higher content of chromium than normal human body, and there is a signifi cant difference between the two. The combination of chromium and people who exercise regularly can increase the biological
activity of insulin in human body. Chromium supplementation will produce the effect of sports and fi tness lipid metabolism, consume fatty. acids, and promote the conversion of amino acids into protein to grow muscle faster, and enhance the size and strength of muscle fi ber. Enhance metabolism. The conclusion is that chromium can effectively repair excessive oxygen free radicals in human body, break the balance between antioxidant, timely repair oxygen free radicals without causing accumulation in the body, reduce the cycle damage of free radicals to the body, etc. People should pay attention to timely supplement chromium after exercise, the body will have a series of good effects.
Effect of aerobic training on selected bio- chemical and anthropometrical var...Sports Journal
The purpose of the study was to find out the effect of aerobic training on bio- chemical and
anthropometrical variables of college men. For this purpose 50 college men were selected from Sri
Ramakrishna Vidyalaya College of Arts and Science. The age of the subjects was ranged between 18 to
23 years. Body Weight and Body Fat were selected as a anthropometrical variable and Low Density Lipo
protein, High Density Lipo protein and Very Low Density Lipo Protein were selected as Bio- chemical
variables. 12 weeks of aerobic training program were given to the subjects, and pre and posttest were
conduced to the subject before and after 12 weeks of time with the use of standard test and qualified
medical personal. The collected data were statistically analyzed by using Paired sample t test. From the
statistical result it was concluded that the Aerobic dance was significantly improved the Bio- chemical
and Anthropometrical characteristic namely Body Weight, Body Fat, Low Density Lipo protein, High
Density Lipo protein and Very Low Density Lipo Protein in 0.05 level of significance
Effect of Four -Weeks Yogic Training Program on Selected Hematological Parame...Sports Journal
The aim of present study was to know the Effect of four - weeks yogic training program on selected Hematological parameters among male students. The training was conducted in the morning session of one hour for the period of four- weeks. The study was conducted on higher secondary school level male students. Total ten male students were be selected as subject. These subjects were selected in terms of purposive samples from the 8th, 9th, 10th, 11th and 12th standards from Senior Secondary Model School Punjabi University Patiala. Two Hematological variables namely Erythrocytes and Leucocytes were selected for the purpose of this research. The results of the study reveals that there was significant effect of four weeks yogic protocol on erythrocytes and leucocytes count among male students.
The document summarizes a study that compared the effects of a high-carbohydrate diet versus a high-fat diet on workout performance over six days. Six participants followed a high-carb diet for three days, then a high-fat diet for three days. Data showed that on a high-carb diet, participants increased speed initially but then decreased or plateaued by day three as carbohydrate stores depleted. However, on a high-fat diet, participants sustained or increased speed for longer periods of time each day as fat provided prolonged energy. The results suggest that a high-fat diet may improve workout performance more than a high-carb diet.
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 document summarizes a literature review on the effects of physical training on asthma in adults. The review analyzed 6 studies that involved a physical training intervention for adults with asthma, measuring effects on physical fitness, pulmonary function, asthma control, and quality of life. The studies generally found that physical training significantly improved measures of physical fitness like VO2max, but results on lung function were inconclusive. Some individual studies reported improvements in asthma control, severity, and quality of life with training, but overall the evidence is insufficient to conclude on effects in those areas. No studies reported any negative effects of exercise on asthma.
The study evaluated the effects of exercise training, with or without supplemental oxygen, on adults with complex congenital heart disease. Eight patients participated in a randomized crossover study that assigned them to exercise initially with or without supplemental oxygen. The results showed that exercise training improved cardiorespiratory fitness, muscle function, and walking distance. Additionally, patients tolerated high-intensity exercise and no safety issues arose. However, recruiting patients proved difficult.
A step towards personalized sports nutrition carbohydrate intake during exe...Rodney Martins
This review article summarizes the current understanding of carbohydrate intake during endurance exercise and proposes new guidelines. Recent studies show that during exercise lasting approximately 1 hour, mouth rinsing with a carbohydrate solution or small amounts of intake can improve performance. For exercise lasting 2-3 hours, the recommendation is to ingest approximately 60 grams of carbohydrate per hour from a single source. During ultra-endurance events, around 90 grams per hour is recommended using multiple transportable carbohydrates. These guidelines account for exercise duration and intensity and provide more specific advice than previous recommendations.
O Chil é uma plataforma online gratuita que visa aumentar a competitividade e integração do setor agroalimentar, fornecendo ferramentas de gestão de conhecimento e serviços como hospedagem de sites, publicação de documentos e eventos. A plataforma permite a comunicação entre profissionais do setor e consumidores e promove os valores europeus da agricultura.
The document examines the effects of a 60-minute moderate intensity spinning class on total body water (TBW) levels in 14 subjects. Bioelectrical impedance analysis was used to measure subjects' pre- and post-exercise TBW. Results showed no significant change in TBW after the spinning class, indicating that moderate intensity spinning does not affect TBW levels.
Glucose and homeostasis model assessment of insulin resistanceMasoumeh Hosseini
This study examined the acute effects of a single moderate-intensity aerobic exercise session on markers of type 2 diabetes in male smokers. Fifteen sedentary male smokers underwent a 40-minute run and had blood samples taken pre- and post-exercise to measure glucose, insulin, and insulin resistance levels. The study found that glucose concentration, serum insulin levels, and insulin resistance decreased significantly following the single exercise session. This suggests that even short-term moderate exercise can positively influence indicators of type 2 diabetes in smokers.
This study aims at exploring the eff ect of a 4-week hypoxic training on some physiological and biochemical parameters in the 400-m competing athletes of the Palestinian athletics team. Twelve trained male athletes were divided into two groups, normoxic training (n = 6) and hypoxic training (n = 6) for residing at sea-level.The training period was 90min, 3 days per week for 4 weeks.Therefore,physiological measurements showed (Vital Capacity (VC), Maximal Oxygen Consumption (VO2max) and Heart-Rate (HR)); Biochemical measurements (Erythropoietin (EPO), Hemoglobin (Hb), Hematocrit (Hct) and Partial Oxygen Pressure PO2); the numerical level of running 400m.
Abstract
Background and purpose: Diet and muscle fiber type are all major factors in predicting intramuscular carnosine concentration [1]. Constituent substrate availability, including the amino acids L-histidine and more specifically beta alanine, play the greatest role in determining the concentration of intramuscular carnosine, a potent intracellular Hydrogen ion buffer. The purpose of this review is to analyze the efficacy of beta alanine supplementation on exercise performance, specifically activities relying on anaerobic glycolysis.
Method: The review included articles from peer-reviewed journals with sufficient data related to the purpose and focus of the study. Inclusion criteria included randomized control trials, systematic reviews and meta-analysis published since 2007.
Results: Twenty relevant studies were identified; various experimental protocols were employed, including both acute and chronic effects of beta alanine supplementation on physical performance. All studies were published 2007 through 2017, providing a robust overview of experimentation over the last 10 years.
Discussion and conclusion: Among studies analyzed in this mini-review, the consensus reached regarding the efficacy of beta alanine supplementation for performance enhancement was relatively positive. Most studies followed similar supplementary strategies, consuming anywhere from 1.6 to 6.4g/day for 2 to 10 weeks. The majority of these studies demonstrated statistically significant increases in intramuscular carnosine content, a physiological parameter that is positively correlated with sprinting and power performance. Many studies presented results in support of enhanced muscular endurance performance subsequent to supplementation relative to the placebo group. Researchers also noted a decline in peak aerobic capacity concurrent to a delay in the onset of blood lactate accumulation, supporting the notion of enhanced glycolytic capacity. More research is necessary to identify optimal dosing strategies for performance optimization across the spectrum of physical activities.
- A meta-analysis of 16 studies found that rinsing the mouth with a carbohydrate solution during endurance exercise has a small but statistically significant effect of improving performance compared to a placebo.
- The overall effect size was 0.28, indicating a small performance benefit from carbohydrate mouth rinsing. Higher carbohydrate concentrations in the mouth rinse resulted in better performance.
- Study characteristics like exercise mode, pre-exercise diet, and type of carbohydrate did not significantly affect the results of the meta-analysis.
Match analysis studies
have also demonstrated that football requires
participants to repeatedly produce maximal or
nearmaximal actions of short durationwith brief
recovery periods [40,45]. For these reasons, foot-
ball training should commonly include physical
exercises aimed to enhance both aerobic fitness
and repeated-sprint ability (RSA).
Beetroot juice supplementation and its effect on 1Kody Springsteen
1. The study aimed to examine the effects of beetroot juice supplementation on 1-mile time trial performance. Ten moderately active subjects (6 male, 4 female) completed 1-mile time trials after consuming either beetroot juice or a placebo drink.
2. Results showed no significant differences in 1-mile time trial times between the beetroot juice and placebo trials for males or females. Time differences between trials for each subject ranged from an improvement of 5 seconds to a decline of 5 seconds.
3. The study found that a single dose of beetroot juice did not significantly improve 1-mile run time trial performance in moderately active males or females, as the p-values for both groups were greater than 0.
IOSR Journal of Humanities and Social Science is an International Journal edited by International Organization of Scientific Research (IOSR).The Journal provides a common forum where all aspects of humanities and social sciences are presented. IOSR-JHSS publishes original papers, review papers, conceptual framework, analytical and simulation models, case studies, empirical research, technical notes etc.
- The document examines the prospective associations between objectively measured physical activity, sedentary time, cardiorespiratory fitness, and cardiometabolic risk factors over 4 years in people with type 2 diabetes.
- It finds that increases in physical activity energy expenditure and cardiorespiratory fitness, and decreases in sedentary time, were associated with improvements in waist circumference, blood pressure, and clustered cardiometabolic risk.
- Baseline measures of these factors were generally not predictive of cardiometabolic risk at the 4-year follow up, suggesting the importance of changes over time rather than single measures.
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.
K. Sletten - Performance enhancing effects of nitrate related supplementsKristian Sletten
This extended paper systematically reviewed 23 studies on the effects of nitric oxide (NO)-related supplementation on aerobic performance in healthy humans. The studies showed that NO supplementation, in the form of beetroot, arginine, citrulline or pharmacological NO substances, can improve exercise performance by increasing time to exhaustion and lowering submaximal oxygen consumption. The ergogenic effects appeared to be more consistent for untrained individuals and with high-intensity exercise. While NO supplements may enhance aerobic performance, the size of the effect depends on training status, exercise type, and supplementation regimen.
Objective to analyze the mechanism and effect of chromium on the recovery of bodybuilding. By consulting the data, the experimental. analysis method was adopted. The results of research practice show that the comparison of relevant indicators among people who exercise regularly shows that people who exercise regularly have a higher content of chromium than normal human body, and there is a signifi cant difference between the two. The combination of chromium and people who exercise regularly can increase the biological
activity of insulin in human body. Chromium supplementation will produce the effect of sports and fi tness lipid metabolism, consume fatty. acids, and promote the conversion of amino acids into protein to grow muscle faster, and enhance the size and strength of muscle fi ber. Enhance metabolism. The conclusion is that chromium can effectively repair excessive oxygen free radicals in human body, break the balance between antioxidant, timely repair oxygen free radicals without causing accumulation in the body, reduce the cycle damage of free radicals to the body, etc. People should pay attention to timely supplement chromium after exercise, the body will have a series of good effects.
Effect of aerobic training on selected bio- chemical and anthropometrical var...Sports Journal
The purpose of the study was to find out the effect of aerobic training on bio- chemical and
anthropometrical variables of college men. For this purpose 50 college men were selected from Sri
Ramakrishna Vidyalaya College of Arts and Science. The age of the subjects was ranged between 18 to
23 years. Body Weight and Body Fat were selected as a anthropometrical variable and Low Density Lipo
protein, High Density Lipo protein and Very Low Density Lipo Protein were selected as Bio- chemical
variables. 12 weeks of aerobic training program were given to the subjects, and pre and posttest were
conduced to the subject before and after 12 weeks of time with the use of standard test and qualified
medical personal. The collected data were statistically analyzed by using Paired sample t test. From the
statistical result it was concluded that the Aerobic dance was significantly improved the Bio- chemical
and Anthropometrical characteristic namely Body Weight, Body Fat, Low Density Lipo protein, High
Density Lipo protein and Very Low Density Lipo Protein in 0.05 level of significance
Effect of Four -Weeks Yogic Training Program on Selected Hematological Parame...Sports Journal
The aim of present study was to know the Effect of four - weeks yogic training program on selected Hematological parameters among male students. The training was conducted in the morning session of one hour for the period of four- weeks. The study was conducted on higher secondary school level male students. Total ten male students were be selected as subject. These subjects were selected in terms of purposive samples from the 8th, 9th, 10th, 11th and 12th standards from Senior Secondary Model School Punjabi University Patiala. Two Hematological variables namely Erythrocytes and Leucocytes were selected for the purpose of this research. The results of the study reveals that there was significant effect of four weeks yogic protocol on erythrocytes and leucocytes count among male students.
The document summarizes a study that compared the effects of a high-carbohydrate diet versus a high-fat diet on workout performance over six days. Six participants followed a high-carb diet for three days, then a high-fat diet for three days. Data showed that on a high-carb diet, participants increased speed initially but then decreased or plateaued by day three as carbohydrate stores depleted. However, on a high-fat diet, participants sustained or increased speed for longer periods of time each day as fat provided prolonged energy. The results suggest that a high-fat diet may improve workout performance more than a high-carb diet.
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 document summarizes a literature review on the effects of physical training on asthma in adults. The review analyzed 6 studies that involved a physical training intervention for adults with asthma, measuring effects on physical fitness, pulmonary function, asthma control, and quality of life. The studies generally found that physical training significantly improved measures of physical fitness like VO2max, but results on lung function were inconclusive. Some individual studies reported improvements in asthma control, severity, and quality of life with training, but overall the evidence is insufficient to conclude on effects in those areas. No studies reported any negative effects of exercise on asthma.
The study evaluated the effects of exercise training, with or without supplemental oxygen, on adults with complex congenital heart disease. Eight patients participated in a randomized crossover study that assigned them to exercise initially with or without supplemental oxygen. The results showed that exercise training improved cardiorespiratory fitness, muscle function, and walking distance. Additionally, patients tolerated high-intensity exercise and no safety issues arose. However, recruiting patients proved difficult.
A step towards personalized sports nutrition carbohydrate intake during exe...Rodney Martins
This review article summarizes the current understanding of carbohydrate intake during endurance exercise and proposes new guidelines. Recent studies show that during exercise lasting approximately 1 hour, mouth rinsing with a carbohydrate solution or small amounts of intake can improve performance. For exercise lasting 2-3 hours, the recommendation is to ingest approximately 60 grams of carbohydrate per hour from a single source. During ultra-endurance events, around 90 grams per hour is recommended using multiple transportable carbohydrates. These guidelines account for exercise duration and intensity and provide more specific advice than previous recommendations.
O Chil é uma plataforma online gratuita que visa aumentar a competitividade e integração do setor agroalimentar, fornecendo ferramentas de gestão de conhecimento e serviços como hospedagem de sites, publicação de documentos e eventos. A plataforma permite a comunicação entre profissionais do setor e consumidores e promove os valores europeus da agricultura.
This document provides tips for freelancers on how to find work. It recommends establishing an online portfolio to showcase skills and using websites like Upwork and 99designs to create profiles. The document stresses the importance of in-person networking and promoting services on social media to potential clients. It also advises freelancers to be professionally prepared with contracts and accounting systems while waiting for work opportunities to arise.
Este documento describe las características y funciones básicas de las plantas. Explica que las plantas son seres vivos capaces de producir su propio alimento y que son beneficiosas para los humanos ya que nos alimentamos de ellas y respiramos el oxígeno que producen. Describe que las plantas, al igual que otros seres vivos, nacen, crecen, se reproducen y mueren. Explica las funciones de la raíz, tallo y hojas y cómo estas cumplen un papel importante en procesos como la fotosí
Este documento presenta resúmenes breves de varios robots y personajes de ficción populares como Wall-E, Optimus Prime, Arturito, Bender, C-3PO, Zeus, Norm, el robot de Síndrome, los Zords de Power Rangers y Bumblebee.
Formato estandar para el diseño de secuencias didacticasjuvenal caballero
La secuencia didáctica tiene como objetivo identificar y analizar estrategias a favor de la preservación del planeta. Se desarrollará en cuatro fases: 1) Preguntarse por qué debemos cuidar el medio ambiente, 2) Explorar conceptos como energía solar, biosfera y recursos naturales, 3) Producir mapas conceptuales sobre estos temas y 4) Aplicar los conocimientos creando dibujos sobre recursos naturales y su cuidado. La evaluación considerará mapas conceptuales, dibujos y trabajo en grupo.
The PHCE Marketing Co. Ltd is a private Mauritian company established in 2013 that provides services for industrial kitchen equipment, laundry equipment, sauna and hammam, and water heaters. The company aims to build long-term client relationships and provide exceptional customer service through innovation and technology. PHCE Marketing has a team of highly qualified technicians with over 10 years of experience who provide maintenance and repairs, supply spare parts, and install new equipment for hotels, restaurants, and other commercial clients.
This weekly homework assignment outlines tasks for a junior high group from Monday to Friday. Students are to write sentences using vocabulary from class on Monday, questions using food words on Tuesday, negative sentences using "must" and "need" on Wednesday, and questions using "must" and "need" on Thursday. Friday's task is not specified.
El documento presenta resúmenes breves de varias películas y series de ciencia ficción que incluyen robots como protagonistas, como WALL-E, RoboCop, y La guerra de las galaxias, entre otros.
This document discusses the importance and features of school museums. It notes that museums bring history and science to life for students in a way that lectures cannot. Museums should contain both ancient and modern collections with some demonstrations of scientific processes. The document then outlines the various advantages of museums, including helping to teach history, geography, and civics. It suggests that museums should have local, national, and international sections. Finally, it stresses the importance of organization, record keeping, and creating an engaging environment in the museum.
El documento presenta una breve descripción de varios robots ficticios. WALL-E fue diseñado para limpiar la Tierra después de que la humanidad la abandonara. EVA fue enviada a investigar si había vida en el planeta. Bumblebee puede transformarse en un Volkswagen amarillo y es adaptable a entornos submarinos. Optimus Prime es el líder de los Autobots en Transformers. Megatron es el líder malvado de los Decepticons. C-3PO fue diseñado para el servicio de los humanos y domina seis millones de formas
Los robots son máquinas automáticas programables capaces de realizar operaciones de manera autónoma y sustituir a los seres humanos en tareas pesadas, repetitivas o peligrosas. Un robot típico tiene un microcontrolador como cerebro, manipuladores y herramientas como extremidades, y sensores como terminales nerviosos. El documento también menciona varios robots famosos de películas y series como WALL-E, R2-D2, Bender y Sonny.
1) El documento describe el origen histórico del Gambito Budapest en una partida de 1918 entre Rubinstein y Mieses, donde Mieses jugó las negras y ganó a pesar de cometer errores, demostrando el potencial de la apertura.
2) Explica que la variante 4.Af4 es una de las respuestas más populares de las blancas contra el Gambito Budapest, buscando oponerse al activo juego de las negras.
3) Señala que el análisis en el documento tiene como objetivo ense
Gunther y sus amigos van a buscar monstruos mutantes en las calles de Nueva York. Encuentran un fragmento de gema alienígena que transforma a un hombre en un cienpies. Luchan contra el cienpies y otros animales mutados. Más tarde encuentran un objeto llamado Ar vour en un templo submarino y luchan contra máquinas mutantes alienígenas. Regresan a la plaza victoriosos con el objeto.
The Scout movement began in 1907 when Robert Baden-Powell held a camping event for boys in England. This led to the publication of Scouting for Boys and the founding of the Boy Scouts. In 1910, the first Girl Guides group was formed to allow girls to participate. Scouting arrived in India in 1909 and was initially only open to European and Anglo-Indian children. The movement focuses on developing youth through activities promoting physical, intellectual, social and spiritual growth based on principles of duty to God, others and self.
The document describes a game where teams have to describe pictures of situations using passive voice in the simple past tense within a time limit to earn points, with the goal of the game being for each team to collect the most points possible by correctly using passive voice to describe the pictures.
Este documento ofrece consejos sobre cómo realizar búsquedas efectivas en Internet. Explica las diferencias entre buscadores, metabuscadores, directorios y guías, y recomienda utilizar diferentes herramientas de búsqueda para obtener resultados más completos. También destaca la importancia de formular preguntas claras utilizando palabras clave relevantes antes de iniciar una búsqueda.
Many successful ultra-endurance athletes have switched from a high-carbohydrate to a low-carbohydrate diet, but they have not previously been studied to determine the extent of metabolic adaptations. The concept that a diet high in carbohydrate is necessary for optimizing exercise performance gained credence in the late 1960s when it was discovered that muscle glycogen depletion was associated with fatigue, and that a high-carbohydrate diet-maintained muscle glycogen and performance.
This document summarizes a study that compared the post-exercise nutrition knowledge and practices of masters (≥50 years) and younger (≤30 years) triathletes in Australia. The study found that over 40% of triathletes did not know the recommended post-exercise carbohydrate and protein intake amounts. Both groups consumed inadequate carbohydrate after exercise compared to recommendations, with masters triathletes consuming significantly less carbohydrate and energy than younger triathletes. The results suggest triathletes have poor knowledge of post-exercise nutrition guidelines and masters triathletes may not be optimizing their recovery with current intake practices.
Circuit training vs cardiovascular endurance exercise (research)Joshua Plisko
This document summarizes a study that compared the effects of circuit training versus traditional cardiovascular endurance exercise in physical education classes. The study found that a six-week circuit training protocol significantly improved students' fitness levels on the PACER assessment, with a 63% greater increase compared to students who did traditional endurance exercise. The purpose of the study was to test an alternative training method to the commonly used jogging in PE classes and see its impact on fitness. It used a causal comparative design to examine ninth grade students assigned to either a circuit training or endurance exercise group that trained 3 times per week.
A Comparative Study of VO2 Max in Young Female Athletes and Non-AthletesIOSR Journals
Abstract:
Aims And Objectives: The purpose of this study was to compare maximum oxygen uptake(VO2
max ) between young female athletes and non-athletes and to show the importance of sports for physical
fitness.
Material & Methods: The present study was carried out in 50 females between the age group of 18-22 yrs.
They were divided into to groups, study group (25 athletes) and control group. (25 non-athletes) The maximum
oxygen uptake (VO2 max) was compared between cases and controls by using Queen’ college step test.(
Harward step test) .
Results: The VO2 max was higher in female athletes than non-athletes.
Conclusion: The present study showed VO2 max levels more in female athletes. Now a days, physical inactivity
is seen among students due to sedentary lifestyle which may lead to many health problems. Hence, we suggest
that students should get involved in sports and it should make a compulsory subject in colleges.
Key words:- VO2 Max; athlete & non athlete ;Young females
The effect of high-fat versus high-carb diet on body composition in strength-...RefoRefaat
Low-fat, high-carb (LFHC) and low-carb, high-fat (LCHF) diets change body composition as a consequence of the reduction of body fat of overweight persons. The
aim of this study is the assessment of the impact of LFHC and LCHF diets on body
composition of men of a healthy body mass who do strength sports while maintaining the appropriate calorific value in a diet and protein intake. The research involved
55 men aged 19–35, with an average BMI of 24.01 ± 1.17 (min. 20.1, max. 26.1). The
participants were divided into two groups following two interventional diets: highfat diet or high-carb diet, for 12 weeks. The body composition of the participants
Effect of brisk walking on body fat percentage of sedentary collegeAlexander Decker
This study examined the effects of a 6-week brisk walking program on body fat percentage in 30 sedentary college students aged 18-25. Body fat percentage was measured before, during, and after the training using skinfold calipers. Results showed a significant reduction in body fat percentage from the beginning to the end of the 6-week training program. While there was no significant difference between the first two measurements, body fat percentage significantly decreased between the second and third, third and fourth, and fourth and fifth measurements, indicating the effectiveness of brisk walking at reducing body fat in this population.
This document discusses aerobic training as part of a pulmonary rehabilitation program for patients with chronic respiratory diseases such as COPD. It provides details on implementing continuous and interval aerobic training, including frequency, intensity, duration, and mode. Both training methods are shown to improve exercise capacity, health-related quality of life, and symptom control, with no significant differences found between moderate and high intensity programs. Ground walking is recommended over stationary cycling to better improve endurance walking capacity.
Physiological responses of general vs. specific aerobic endurance exercises i...Fernando Farias
The study aimed to compare the physiological and perceptual
responses of two high intensity intermittent aerobic exercises (HIIE), i.e. the
15s/15s exercise and an exercise on the Hoff track (HTE).
This study evaluated a novel method for indirectly assessing muscle glycogen levels in athletes through non-invasive measurements of maximal blood lactate levels ([La-]b max) and maximal carbohydrate oxidation rates (CHOox max). The results showed that 30% of men and 24% of women had suboptimal [La-]b max, indicating lower glycogen levels. [La-]b max, CHOox max, and respiratory exchange ratio were significantly higher in athletes with optimal vs. suboptimal [La-]b max, while fat oxidation was lower. This suggests [La-]b max and CHOox max may be a practical way to identify athletes with insufficient glycogen storage and risk for impaired performance.
Carbohydrates are the primary fuel source for endurance athletes like marathon runners. Research shows that consuming carbohydrates improves athletic performance by storing glucose in the form of glycogen in muscles and liver. A carbohydrate load diet in the days leading up to a marathon maximizes glycogen storage and increases energy available during the race. Specifically, carbohydrate intake 1-3 days before a marathon is associated with faster race times compared to intake only on the morning of or during the race. Athletes should aim to consume 6-10 grams of carbohydrates per kilogram of body weight daily as part of their training diet in order to perform at their best in marathons and other endurance events.
Effect of aerobic exercise on walking capacity in subjects with parkinsonism-...Sports Journal
This literature review examines the effect of aerobic exercise on walking capacity in subjects with parkinsonism. Seven studies that utilized aerobic exercises like treadmill training and body weight supported treadmill training with subjects with Parkinson's disease were reviewed. The results across the studies found that aerobic exercise improved walking parameters like speed, stride length, home ambulation, and reduced movement initiation time. The literature review concluded that aerobic exercises can improve walking capacity in patients with parkinsonism.
exercise as determinant prevention of high blood pressure in container crane ...INFOGAIN PUBLICATION
Metabolic syndrome (Mets) is a multiple risk factor for coronary heart disease, diabetes, and several organ malfunctions that comes up from insulin resistance and metabolic dysfunctions caused of abnormal adipose deposition. One of the component criteria of metabolic syndrome is elevated blood pressure. Unhealthy lifestyle and sedentary physical activity are considered to have relationship with metabolic syndrome incidents in workers. This study aimed to analyze smoking habit, regular exercise and family’s medical history associated with blood pressure using International Diabetic Federation Criteria for Mets in a container crane operator’s population. The study was explored in a cross sectional study of 40 container crane operator. Using logistic regression for analyzing, the study found that regular exercise had significant association with blood pressure in worker adjusted with age.
The document discusses a study assessing NCAA swimmers' use of sodium bicarbonate (SB), including their knowledge, beliefs, and perceived benefits. It reviews literature showing many athletes consume supplements without fully understanding them. Studies found swimmers commonly use multivitamins and creatine. SB acts as a buffer against lactic acid buildup, potentially improving short-term, high-intensity performance. However, its effects on swimmers specifically are unclear due to limited research. The purpose of this study is to understand NCAA swimmers' SB use, attitudes, and nutrition knowledge.
EFFECTS OF HIGH INTENSITY INTERVAL TRAINING AND HIGH VOLUME ENDURANCE TRAINING Fernando Farias
Maximal aerobic capacity increased significantly
in both the HIIT and HVET group in
response to the 6 week training program, and the percentage improvement was
similar (7%)
in both groups.
There was no change in CMJ, CMJ flight time or 5 m speed in either group in
response to training. Compared to baseline, performance in the VJ and 20 m sprint
decreased significantly in the HVET group following the 6 week train
ing program, and did
not change in the HIIT group. Average power and peak power during the fifth and sixth
cycling test increased and the rate of fatigue decreased in the HIIT group only.
1) The study examined the effects of a 6-week aerobic exercise program on serum resistin levels in 24 sedentary obese women divided into an exercise or control group.
2) While the exercise group showed improvements in body weight and abdominal obesity after the program, their serum resistin levels did not change significantly compared to pre-training levels.
3) The findings suggest that more substantial weight loss, of at least 5% of body weight, may be needed to see improvements in adipocytokine levels like resistin in obese individuals.
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.
3. 646 Hansen et al.
60 g/hr when glucose is consumed and up to 90 g/hr when
a combination of glucose and fructose is consumed (Burke
et al., 2011; Jeukendrup, 2011).
A previous study has shown that marathon runners
in general consume less fluid and carbohydrate during
competition than the scientifically based recommended
amounts. Thus, Pfeiffer et al. (2012) reported a fluid intake
of 0.354 ± 0.187 L/hr and a carbohydrate intake of 35 ±
26 g/hr during a marathon with a mean finish time of 3:46
hr. This suggests that there could be a potential for perfor-
mance enhancement by intervening with a scientifically
based nutritional strategy in endurance events.
Hottenrott et al. (2012) conducted a nutritional inter-
ventionstudyinwhichtheycomparedcyclingperformance
achieved by applying scientifically based and freely chosen
nutritionalstrategies.Cyclingwasperformedonanergome-
ter,inalaboratory.Briefly,thestudyshowedthatendurance-
trained cyclists performed a 64 km time trial on average
6.3% faster when applying the scientifically based as com-
pared with the freely chosen nutritional strategy. The study
wasperformedasarandomizedcrossoverstudyinwhichthe
cyclistsfirstperformeda2.5-hrcyclingboutat70%oftheir
maximal oxygen uptake and subsequently the 64 km time
trial. The scientifically based nutritional strategy consisted
of a target intake of 60 g maltodextrin and glucose, 30 g
fructose, 0.5 g sodium, and 0.05 g caffeine per hour. The
study also revealed that the cyclists on average consumed
20%and28%lessfluidandcarbohydrate,respectively,when
applying their freely chosen as compared with the scientifi-
cally based nutritional strategy. It is unknown whether it
is possible to achieve a similar performance enhancement
through a nutritional intervention with marathon runners
during real world competition conditions.
Gastrointestinal(GI)symptomsduringrunningmight
cause runners to reduce intake of fluid and carbohydrate.
Runners competing in marathon races have been reported
to suffer from GI symptoms (Rehrer et al., 1989). On the
other hand, studies have also shown that during intense
16 km endurance runs, where the runners had a high car-
bohydrate intake through energy gels, GI symptoms were
generally low. At the same time, there was a correlation
between GI symptoms during the runs and history of GI
symptoms (Pfeiffer et al., 2009; Pfeiffer et al., 2012). Obvi-
ously, serious GI symptoms can influence performance in
a marathon race.
The main purpose of the current study was to test the
hypothesis that a marathon race could be completed faster
by applying a scientifically based nutritional strategy as
compared with a freely chosen nutritional strategy. In addi-
tion, GI symptoms were evaluated for all runners involved
sinceGIsymptomscanaffectfluidandcarbohydrateintake
during a marathon race and eventually affect performance.
Methods
Participants and Experimental Design
Following approval by the ethical committee ofThe North
Denmark Region Committee on Health Research Ethics,
104 nonelite marathon runners, who fulfilled the study’s
inclusion criteria, volunteered. Inclusion criteria were that
volunteers should be healthy men or women between 18
and 60 years and planning to run Copenhagen Marathon
2013 (CPH2013). The volunteers signed informed con-
sent forms. Their characteristics are included in Figure
1. The study was designed as a matched pairs design
(Figure 1) that has a relatively large statistical power
compared with the number of participants. A substantial
dropout during the training and familiarization period
before the marathon race was anticipated. In addition, it
was necessary to have an ample number of runners for
a strict pairing process. Consequently, it was assessed
necessary to initially recruit a considerable number of
just over one hundred runners at the very beginning of the
study. These runners were subsequently divided in two
groups and eventually, after a training and familiarization
period, pairs were matched with one runner from each
group, as described in details below. One of the groups
(FRE) had to apply a freely chosen nutritional strategy
in CPH2013, while the other group (SCI) had to apply a
scientifically based nutritional strategy in the same race.
Division of Runners Into Two Groups
As a part of the process of creating two comparable
groups of runners from which the pairs could subse-
quently be matched, the runners initially responded to
a self-administered questionnaire on basic characteris-
tics like body mass, height, and age. In addition, they
answered questions about their previous marathon race
experience and their self-estimated finish time in the
upcoming marathon race. Furthermore, the runners
performed a 10.0 km running time trial approximately 7
weeks before CPH2013. For this running time trial, the
runners were instructed to run in a flat terrain without
traffic lights or other hindrances and perform the trial
in a nonfatigued condition. The time to complete the
10 km running time trial was reported to the authors.
Based on the 10 km running time trial time and the self-
administered questionnaire responses, the runners were
divided into comparable groups.
Two Different Nutritional Strategies
Runners in FRE applied their own freely chosen nutri-
tional strategy in the marathon race. Further, runners in
FRE were not informed about the nutritional strategy
applied by runners in SCI. For comparison, runners in SCI
applied a scientifically based nutritional strategy consist-
ing of a combined intake of energy gels (H5 EnergyGel+,
H5 Ltd, Leicestershire, UK) and water. Runners in SCI
were instructed to consume two energy gels and 0.200
L of water 10 to 15 min before the start of CPH2013.
Furthermore, these runners were instructed to consume
one energy gel at the 40th min after the start of the race
and subsequently one gel every 20th min in the remainder
of the race.A single gel contained 20 g maltodextrin and
glucose, 0.02 g sodium, and 0.03 g caffeine. With regard
4. Marathon and Nutritional Strategy 647
to the water intake, runners in SCI were instructed to drink
at the official race depots.An intake of 0.750 L water per
hr was the recommended target. Depending on estimated
finish time and the distance between the water depots,
runners were presented with an individualized plan for
their water intake. This plan consisted of a table in which
the runners were able to see how many cups (0–2 cups)
of water, they should consume at each of the 10 official
race depots. Each cup contained approximately 0.200
L of water. Runners were recommended to stop while
consuming water, to minimize spill and thereby secure
an adequate intake. By following the scientifically based
nutritional strategy strictly, each runner would consume
close to the target intake of 0.750 L water, 60 g malto-
dextrin and glucose, 0.06 g sodium, and 0.09 g caffeine
per hour.
Familiarization
Four to five weeks before CPH2013, all runners in both
groups were asked to complete a half marathon. For the
runners in SCI, the half marathon served as a familiar-
ization session in which they gained experience with the
scientifically based nutritional strategy that they should
Figure 1 — Flowchart illustrating the progress of runners in the study. FRE, freely chosen nutritional strat-
egy; SCI, scientifically based nutritional strategy. The data on body mass is self-reported. *Different from
FRE (p = .023).
5. 648 Hansen et al.
apply later in the marathon race. Thus, they applied the
same nutritional strategy in the half marathon as in the
marathon race.As a part of the strategy, energy gels were
carried by the runners in belts. For further familiarization
during training, each runner in SCI was supplied with 20
energy gels 30 days before CPH2013. It has been recom-
mended that athletes practice their nutritional strategy
to train the gut’s capacity to absorb carbohydrate during
exercise and thereby increase exogenous carbohydrate
oxidation (Jeukendrup, 2011).
Training
All runners in both groups were asked to follow their
own personal training regimen in the run-up to CPH2013.
Runners submitted a training journal by the end of each
week during the last 11 weeks before the marathon race.
In the weekly training journal the runners had to report
the following three training variables regarding the last
week’s training: total number of covered km, total number
of running sessions, and number of running sessions that
involved interval run. For each runner, a single mean
value was initially calculated across the 11 weeks for
each of the three variables by summing all the weekly
submitted values and dividing this sum by the number of
weeks that the runner had submitted a training journal.
Subsequently, the overall mean (and standard deviation,
SD) for each group across the entire 11-week period was
calculated for each training variable.
Matched Pairing
The day before the marathon race, runners from SCI were
paired with runners from FRE according to gender as
well as their reported 10 km running time trial time. The
strict matching criteria were that pairs had to consist of
runners 1) of the same gender and 2) with a maximal dif-
ference of 1% in the 10 km running time trial time. Only
pairs that fulfilled these matching criteria were included,
and that resulted in a total of 14 matched pairs (Table 1).
The Marathon Race
Between 90 and 15 min before the start of CPH2013, all
runners were weighed (Tanita, Model HD-351, Tokyo,
Japan) wearing their running clothes and shoes. At the
same time, blood glucose was measured in a single drop of
blood taken from a fingertip. A Contour XT Meter (Bayer
HealthCare, Toronto, Canada) was used for this blood
analysis.Anearlierversionofthisbloodglucosemeasuring
apparatus has been reported to have a very high accuracy
(Pfützner et al., 2012). Finish time and split times for each
runner were measured by the race officials of CPH2013
usingaRFIDchip(UltimateSportServiceApS,Svendborg,
Denmark). Approximately 5 to 10 min after finishing the
marathon race, the runners were weighed again, wearing
the same clothes as during the weighing before the race.
In addition, at the same time, blood glucose was measured
again, applying the same method as before the race.
Table 1 Marathon Race Experience and Estimated Marathon Running Ability in the Form of Self-
Reported 10 km Running Time Trial Time Obtained Before CPH2013
Previously Completed
Marathon?
Self-Reported 10 km Running Time
Trial Time
Finish Time in CPH2013
FRE SCI FRE SCI FRE SCI
1+15 yes yes 0:38:15 0:37:52 3:03:15 2:48:21
2+16 yes yes 0:39:12 0:39:25 3:12:47 2:55:07
3+17 yes no 0:41:56 0:41:39 3:22:54 3:31:55
4+18 yes yes 0:42:10 0:42:15 4:08:33 3:23:42
5+19 yes yes 0:42:34 0:42:45 3:43:12 3:56:12
6+20 yes no 0:44:21 0:44:22 3:52:07 3:38:30
7+21 yes yes 0:44:46 0:45:01 3:38:42 3:37:25
8+22 no yes 0:45:10 0:45:15 3:56:44 3:37:24
9+23a yes yes 0:47:48 0:47:46 3:54:34 3:45:53
10+24 yes no 0:48:44 0:49:02 3:48:28 3:36:51
11+25 yes no 0:49:11 0:49:17 3:56:37 3:43:51
12+26a yes yes 0:49:53 0:49:56 3:55:55 3:50:49
13+27a yes no 0:50:20 0:50:41 4:09:03 3:59:38
14+28 no yes 0:55:01 0:55:01 4:49:00 4:33:29
Mean 0:45:40 0:45:44 3:49:26 3:38:31
± SD ± 0:04:32 ± 0:04:37 ± 0:25:05 ± 0:24:54b
Note. Included is also marathon finish time in CPH2013.
aPairs consisting of females.
bDifferent from FRE (p = .010).
6. Marathon and Nutritional Strategy 649
Intake and Gastrointestinal Symptoms
Same evening after the marathon race, all runners received
a self-administered questionnaire regarding their intake
of water, energy drink, energy gels, fruit, and any other
products from 15 min before the start and throughout the
race. The carbohydrate content of the different products
was assessed from the product manufacturers’ homep-
ages or from standard tables (Hark & Deen, 2006). The
questionnaire also addressed GI symptoms during the
race, with respect to abdominal symptoms such as reflux,
heartburn, nausea, bloating, vomiting, abdominal pain,
urge to defecate, and diarrhea—as well as such systemic
symptoms as headache, dizziness, urge to urinate, and
muscle cramps. Runners assessed the GI symptoms on a
10-point scale ranging from 0, no problem at all, to 9, the
worst it has ever been.This way of assessing GI symptoms
is based on the method applied by Pfeiffer et al. (2009).
Statistical Analysis
A statistical power analysis applying an alpha level of
0.05, a power of 0.80, and a SD of 24 min estimated that
an 8% difference in performance could be detected with 16
pairs.The Kolmogorov–Smirnov test was applied to evalu-
ate whether data were normally distributed. Student’s two-
tailed unpaired and paired t tests were applied whenever
appropriate. To test for differences between FRE and SCI
in running velocity throughout the marathon race, two-way
repeated-measuresANOVA with section of the marathon
course as within-subject factor and nutritional strategy as
between-subject factor was performed. As post hoc test,
Student’s paired samples two-tailed t tests with step-down
Holm-Bonferroni adjustment (Ludbrook, 1998) were
applied. GI symptoms were evaluated with Wilcoxon’s
signed-rank tests since most data were mainly recorded
in the no problems at all category and were therefore not
normally distributed. GI symptoms that were scored >4
were termed serious. Pearson’s correlation coefficients
were calculated for correlations between 10 km running
time trial time and finish time for CPH2013 for FRE and
SCI separately. Spearman’s correlation coefficient was
calculated for correlations between nonparametric data,
such as GI symptoms and history of GI symptoms. Effect
size (ES) was calculated as: ES = (Me—Mc)/SDc, where
Me and Mc represent mean of experimental and control
group, respectively. SDc represents standard deviation of
the control group. Classification of ES was as follows:
0.2, small difference; 0.5, moderate difference; 0.8, large
difference.Version 20 of IBM SPSS Statistics was applied
(SPSS Inc., Chicago, IL, USA). Data are presented as
mean ± SD unless otherwise indicated. The significance
level was set at p < .05.
Results
Environmental Race Conditions
CPH2013 took place in Copenhagen 19th May 2013
between 9:30 a.m. and 3:30 p.m. Conditions were cloudy
and rainy. Air temperature was 15°C at 9:30 a.m., 17°C
at 12:00 a.m., and 19°C at 2:00 p.m. Barometric pres-
sure was 1019 hourPa. Wind speed was on average 3
m/s, and relative humidity was 93%, while 7 mm of rain
was registered during the race. The 42.195 km marathon
course in CPH2013 can be described as relatively flat.
Baseline
Height, body mass, and gender distribution were not
different between FRE and SCI (p = .179 and p = .427,
respectively). However, runners in FRE were younger
than runners in SCI (p = .023; Figure 1). There was no
significant difference between the two groups in the 10
km running time trial time (p = .246; Table 1). Pearson’s
correlation coefficient showed high correlation between
the 10 km running time trial time and finish time in
CPH2013 for both FRE (r = .842, p < .001) and SCI (r =
.865, p < .001; Figure 2). Training regimen in the run-up
to CPH2013 was not different between FRE and SCI.
This applies to both total number of covered km (FRE:
31.9 ± 10.6 km/week, and SCI: 35.0 ± 12.2 km/week;
p = .462), total number of running sessions (FRE: 2.6 ±
0.6 running sessions/week, and SCI: 2.6 ± 0.7 running
sessions/week; p = .817), as well as number of running
sessions that involved interval running (FRE: 0.7 ± 0.4
sessions/week, and SCI: 0.4 ± 0.3 sessions/week; p =
.081). There was no difference between FRE and SCI
with regard to compliance of reporting training, which
amounted to 94 ± 10% and 96 ± 8%, respectively (p =
.864). Twelve and 14 runners in FRE and SCI, respec-
tively, performed a half-marathon in the preparation phase
before the marathon race.
Intake of Carbohydrate and Fluid
Carbohydrate intake was 145.6 ± 70.3 g and 234.3 ± 46.6
g for runners in FRE and SCI, respectively (p = .003;
Figure 2 — Correlation between prerace 10 km running time
trial time and marathon finish time in CPH2013.
7. 650 Hansen et al.
Table 2). Runners in FRE had their carbohydrate from
energy drinks, gels, and fruit. Fluid intake was 2.34 ±
0.93 L and 2.44 ± 0.65 L for runners in FRE and SCI,
respectively, and not different between groups (p = .740;
Table 2).
Performance
The self-reported best marathon finish time (3:43 ± 0:22
hr, performed 1.5 ± 0.8 years before CHP2013) of the
runners who had previous marathon experience (n = 20)
was comparable with the finish time in the current study
(Table 1). Finish time for runners in SCI was 10:55 ±
13:09 min shorter than for runners in FRE, which corre-
sponds to a 4.7 ± 5.6% difference (p = .010; Table 1). The
effect size was –0.43. Figure 3 represents an illustration
of the development of running velocity throughout the
marathon race for the two groups. The ANOVA showed
that there was a significant interaction between section of
the marathon course and nutritional strategy (p < .001).
The post hoc analysis showed that running velocity was
significantly different between FRE and SCI from section
30 to 35 km and through the rest of the race (p = .003
to .005). The correlation coefficient (r) was –0.205 (p =
.295) for correlation between carbohydrate intake (g/hr)
and finish time when including all 28 runners.
Body Mass and Blood Glucose
Before the marathon race, the measured body mass in FRE
andSCIwas79.0±10.8kgand75.5±15.2kg,respectively
(p = .679).After the race, body mass in FRE and SCI was
78.9 ± 10.7 kg and 75.4 ± 14.9 kg, respectively (p = .662).
Body mass was not different before as compared with after
the race, which applies to both FRE (p = .888) or SCI (p
= .589). The changes in body mass from before to after
the race were not different between the groups (p = .665).
Before the marathon race, blood glucose in FRE and
SCI was 4.8 ± 0.5 mmol/l and 5.1 ± 0.5 mmol/l, respec-
tively (p = .419).After the race, blood glucose in FRE and
SCI was 4.9 ± 0.7 mmol/l and 6.3 ± 0.9 mmol/l, respec-
tively (p = .002). Blood glucose was not different before as
compared with after the race for FRE (P = .644). In con-
trast, blood glucose was higher after than before the race
for SCI (p = .0003). The changes in blood glucose from
before to after the race were different between the groups
(p = .001). The effect size of these changes was 2.39.
GI Symptoms
GI symptoms, as experienced in the marathon race and
subsequently reported by the runners, were not different
between FRE and SCI (p = .140 to 0.823; Table 3). None
Table 2 Intake of Carbohydrate and Fluid in CPH2013 (Mean ± SD)
Nutritional Strategy Carbohydrate Fluid
(g/hr) (g/kg BM) (L/hr) (L/kg BM)
FRE 38.0 ± 17.5 1.9 ± 1.0 0.603 ± 0.209 0.029 ± 0.012
SCI 64.7 ± 12.3a 3.2 ± 0.9b 0.681 ± 0.193 0.034 ± 0.009
Note. Data are mean ± SD. BM is body mass measured before the start of CPH2013. Regarding data for FRE: n = 14
for intake per hr, and n = 12 for intake per kg body mass. Regarding data for SCI: n = 14 for intake per hr, and n = 13
for intake per kg body mass. Different from FRE:
ap = .002.
bp = .021.
Figure 3 — Development of running velocity throughout the marathon race. *Different from FRE (p
= .003 to .005).
8. Marathon and Nutritional Strategy 651
of the mean scores exceeded 4 that in the current study
would have been termed serious. Runners in both groups
reported no problem at all or very minor problems during
the race with regard to headache, dizziness, heartburn,
nausea, bloating, and vomiting.
Runners in FRE had no problem at all or very minor
problems with regard to reflux. Three runners (21%) in
FRE reported serious abdominal pain during the race with
scores ranging between 6 and 7. One participant (7%) in
FRE reported serious symptoms in urge to defecate and
diarrhea with a score of 9 in both symptoms. Two run-
ners (14%) in FRE reported serious urge to urinate with
scores of 5 and 9. Three runners (21%) in FRE reported
serious muscle cramps with scores ranging between 6
and 9. Spearman’s correlations coefficient showed fair
correlation between abdominal symptoms during the race
and history of abdominal symptoms (r = .613, p = .020),
while there was no correlation between systemic symp-
toms during the race and history of systemic symptoms
(r = .356, p = .212) for runners in FRE.
Runners in SCI reported no problem at all or very
minor problems with regard to abdominal pain during the
race. One participant (7%) in SCI reported serious symp-
toms in reflux with a score of 8. One participant (7%) in
SCI reported serious symptoms in urge to defecate with
a score of 7. Three runners (21%) in SCI reported seri-
ous urge to urinate during the race with scores ranging
between 5 and 8. Three runners (21%) in SCI reported
serious muscle cramps with scores ranging between 6
and 7. Spearman’s correlations coefficient showed a high
correlation between abdominal symptoms during the race
and history of abdominal symptoms (r = .765, p < .001),
while there was no correlation between systemic symp-
toms during the race and history of systemic symptoms
(r = .106, p = .718) for runners in SCI.
Discussion
The current study focused on nutritional strategy, intake,
performance, and GI symptoms in nonelite runners
performing a marathon race. It resulted in three major
findings. First, runners who applied a freely chosen nutri-
tional strategy consumed considerably less carbohydrate
than runners applying a scientifically based strategy did.
Second, finish time in the race was longer for runners
applying the freely chosen nutritional strategy. Third, GI
symptoms were not different between runners applying
the two different nutritional strategies.
Fluid Intake and Hydration State
Fluid intake was not different between FRE and SCI, and
at the same time it was within a recommended range of
0.400 to 0.800 L/hr (Sawka et al., 2007). In addition, the
fluid intake was larger than previously reported voluntary
intake (Pfeiffer et al., 2012). This indicated that both
groups in the current study apparently were hydrated, and
that dehydration did not play a key role for performance.
Measurements of body mass before and after the mara-
thon race supported this. Hence, neither in FRE nor in SCI
was the body mass different after the race as compared
with before. Still, one important note should be made
regarding the body mass. Runners were weighed in dry
conditions before the race, while the runners were wet
at the weighing after the race due to rain during the race.
A test performed in our laboratory after the race showed
that an estimated 0.90 L of fluid, or 0.90 kg, could be
contained in a runner’s wet clothes, typically consisting of
just shirt, shorts, socks, and shoes. Still, subtracting this
mass from the runners’ body mass after the race resulted
in body mass losses of less than 2% that is considered
Table 3 Self-Reported Scores of GI Symptoms in CPH2013
Symptom
FRE SCI
Min Max Mean (Median) Min Max Mean (Median)
Abdominal symptoms
reflux 0 3 0.29 (0) 0 8 1.21 (0)
heartburn 0 0 0 (0) 0 1 0.14 (0)
nausea 0 3 0.43 (0) 0 3 0.21 (0)
bloating 0 4 0.29 (0) 0 3 0.21 (0)
vomiting 0 0 0 (0) 0 1 0.14 (0)
abdominal pain 0 7 1.79 (0) 0 3 0.86 (0)
urge to defecate 0 9 1.14 (0) 0 7 0.50 (0)
diarrhea 0 9 0.64 (0) 0 0 0 (0)
Systemic symptoms
headache 0 4 0.43 (0) 0 0 0 (0)
dizziness 0 4 0.64 (0) 0 2 0.36 (0)
urge to urinate 0 9 2.57 (2.5) 0 8 2.14 (1)
muscle cramps 0 9 2.21 (0.5) 0 7 1.79 (0)
Note. Min and max are lowest and highest reported scores in the groups, respectively. n = 14 for FRE; n = 14 for SCI.
9. 652 Hansen et al.
a threshold below which endurance performance is not
affected negatively (Montain, 2008; Shirreffs & Sawka,
2011).A rough estimate of the sweat rate, assuming a 0.9
kg loss of body mass and a fluid intake of 2.3 l, amounts
to 0.9 L/hr that compares reasonable well with sweat
rates in comparable activities and weather conditions
(Sawka et al., 2007).
Carbohydrate Intake and Performance
Carbohydrate intake in FRE was comparable to previ-
ously reported voluntary intake (Pfeiffer et al., 2012).
More importantly though, it was considerably lower
in FRE than in SCI. And it is likely that this difference
in carbohydrate intake between FRE and SCI was the
major reason for the difference in performance between
the two groups in the current study. The lower intake
of carbohydrate might have resulted in less effective
metabolic processes for runners in FRE including less
glucose supply to the brain (Nybo, 2003a; Nybo et al.,
2003b) and working muscles (McConell et al., 1999).
During the first part of the marathon race, the body con-
tains a storage of glycogen which is gradually broken
down. This storage is only sufficient for a limited time
when applying a particular workload. Thereafter, running
velocity will decrease because of insufficient supply of
glucose. This has previously been shown for prolonged
cycling (Widrick et al., 1993). It should also be noted
that marathon finish time has previously been correlated
with carbohydrate intake indicating better performance
with larger intake (Pfeiffer et al., 2012).
The maximal uptake of glucose is approx. 60 g/hr as
previously summarized (Burke et al., 2011; Jeukendrup,
2011). That amount is in line with the intake in SCI in
the current study. Still, it should be noted that research
has shown that it is possible to enhance performance by
ingesting even larger total amounts of combined multiple
transportable carbohydrates of glucose and fructose in
a ratio of 2:1 (Currell & Jeukendrup, 2008). The latter
was found by having cyclists cycling for 2 hour while
ingesting a total amount of carbohydrate of 1.8 g/min
consisting of either a glucose-only beverage or a glucose
and fructose beverage. An argument for not producing
energy gels consisting of combined glucose and fructose
is that the latter causes the gels to have a (too) sweet
taste, which might cause that athletes ingest inadequate
amounts of gels.
Of note is that elite marathon runners apparently
over the last several years have increased focus on in-
race nutrition and hydration practices and actually have
an intake that corresponds to the present intake by the
runners in SCI (Stellingwerff, 2012; Stellingwerff, 2013).
Caffeine
The gels that were used in the current study contained
caffeine. Thus, the better performance that was observed
for runners in SCI as compared with runners in FRE
was obtained with a combined intake of carbohydrate
and caffeine in SCI. Caffeine has been shown to be
able to enhance running (Wiles et al., 1992) and cycling
performance (Kovacs et al., 1998). The reason for the
performance enhancing effect is, however, not fully under-
stood. It has been shown that caffeine intake increases the
overall concentrations of plasma free-fatty acids, which
potentially could have a sparing effect on the carbohydrate
storage in the body during prolonged exercise (Cox et al.,
2002). Others have shown that caffeine intake increased
the exogenous carbohydrate oxidation rate and suggested
that this was mediated through increased intestinal glucose
absorption and eventually could result in performance
enhancement (Yeo et al., 2005). In addition, it has been
speculated that caffeine has an impact on the central ner-
vous system, causing signals of fatigue during exercise to
be overridden (Cox et al., 2002). In the study byYeo et al.
(2005) exogenous glucose oxidation was investigated in
cyclists during 2 hour of cycling. It was reported that this
was 26% higher when adding a caffeine intake of 5 mg/
kg/hr to a glucose drink intake (48 g/hr) as compared with
ingesting the same glucose drink without caffeine. In the
study by Kovacs et al. (1998), time trial cycling perfor-
mance (lasting about 1 hr) was investigated in a group of
triathletes and cyclists. It was reported that performance
was enhanced when adding a caffeine intake of 3.2 mg/
kg/hr to the intake of a fluid that contained 68 g/L glucose.
However, when only adding a caffeine intake of 2.1 mg/
kg/hr, the performance was not different from performance
obtained by intake of the glucose drink without caffeine
(Kovacs et al., 1998). In the current study, caffeine intake
was on average 1.00 mg/kg/hr for the runners in SCI. This
amount was thus considerably lower than the amounts
applied in the studies by Yeo et al. (2005) and Kovacs et
al. (1998). It is therefore suggested that the difference in
performance between the two groups in the current study
was primarily caused by the difference in carbohydrate
intake between runners in SCI and runners in FRE. In
further support of this, it occurs unlikely that all runners
in FRE ingested complete caffeine free products. In other
words, it is likely that at least some of the runners in FRE
did also have some caffeine intake, although this can
unfortunately not be documented.
Blood Glucose
Runners in SCI had higher blood glucose concentrations
after the marathon race than before the race. That may
intuitively appear surprising. However, it has previously
been reported that blood glucose increases in the initial
phase of recovery following intense exercise, and that
this possibly is a result of an imbalance between glucose
production and utilization in which production exceeds
utilization for the initial 5 min (Calles et al., 1983). One
interpretation of the higher blood glucose values after the
race in SCI, while not in FRE, could be that the higher
total intake of carbohydrate throughout the race in SCI
caused carbohydrate availability in only that group to be
large enough for excess glucose production in the initial
phase after the finish.
10. Marathon and Nutritional Strategy 653
GI Symptoms
GI symptoms in both FRE and SCI were generally low,
which indicated that runners overall had a high level of
GI tolerance. Notably, the higher carbohydrate intake
in SCI, as compared with that in FRE, did not result in
more GI symptoms. The GI symptoms in the current
study are comparable to those reported by Pfeiffer et
al. (2009, 2012). Furthermore, the individually reported
abdominal symptoms from the marathon race in the
current study were positively correlated with history
of abdominal symptoms. This is a finding that has also
reported previously (Pfeiffer et al., 2009, 2012). An
interpretation is that the prevalence and severity of GI
symptoms does not seem to be affected by the intake
of carbohydrates during a marathon race but rather
by individual tolerance and history of GI symptoms.
Whether individual GI tolerance is trainable remains
to be investigated more thoroughly.
Strengths and Limitations of the Study
As part of the preparation for the marathon race, run-
ners in SCI familiarized themselves with the scientifi-
cally based nutritional strategy. This was done in a half
marathon 4–5 weeks before CPH2013 and in addition
during training before the marathon race. It has previ-
ously been advised that athletes test their tolerance
during hard training sessions, ideally under conditions
similar to those of the race that they are going to com-
pete in (Pfeiffer et al., 2009). The runners’ own training
regimens were not interfered with, since this was not a
training intervention study. Merely, to be able to describe
the training that was performed, runners were asked
to report training diaries. Based on these reports, it is
suggested that training was similar in FRE and SCI and
therefore not influencing the difference in performance
observed between the two groups. The two groups
were similar with regard to height, body mass, gender,
self-estimated marathon finish time, and 10 km running
time trial time. However, runners in FRE were on aver-
age approximately 8 years younger than runners in SCI
were. It is though suggested that the age difference was
not in favor of SCI with regard to performance. Direct
observation of intake was not an option in the current
study due to limited resources. Therefore, the memory
of the runners was relied on, which can be a challenge
in prolonged exercise such as a marathon (Rutishauser,
2005). The target carbohydrate intake was the same for
all runners in SCI regardless of individual factors. It is
thus possible that more individualized strategies taking
into account for example body mass and history of GI
symptoms would have resulted in even larger difference
in performance between FRE and SCI than observed.
Carbohydrate loading before prolonged running can
enhance performance (Fallowfield & Williams, 1993)
and there could have been a difference in carbohydrate
loading between the two groups. However, the current
study did not focus on this aspect.
Practical Perspectives
It is unknown why nonelite runners apparently ingest
too little carbohydrate during marathon races. Possible
reasons for an inadequate intake could include fear of GI
symptoms and inadequate availability of carbohydrate
during the race. It is also possible that runners do not have
sufficient knowledge about scientifically based nutritional
strategies and that they do not familiarize themselves
sufficiently with adequate intake during training. Still,
the current study indicates that all these aspects are either
exaggerated or can largely be dealt with.A practical per-
spective of the current study is that, apparently, it requires
an informational and perhaps even pedagogical effort by,
for example, coaches, trainers, or other influential persons
to close the performance-deteriorating gap between the
freely chosen and the scientifically based intake. Seem-
ingly, nonelite runners are not by themselves focusing
sufficiently on their nutritional strategy and its association
with their performance as it has been reported previously
(O’Neal et al., 2011).
Conclusions
It was tested whether a marathon race was completed
faster by applying a scientifically based rather than a
freely chosen in-race nutritional strategy. It was found
that nonelite runners completed a marathon race on aver-
age 11 min, corresponding to 5%, faster by applying a
scientifically based nutritional strategy as compared with
a freely chosen nutritional strategy. Furthermore, average
values of gastrointestinal symptoms were low and not
different between the two groups of runners that applied
the two different nutritional strategies.
Acknowledgments
Runners are thanked for their enthusiastic participation in the
study. H5 Ltd, Leicestershire, United Kingdom, EnergySport,
Langvad, Denmark, Sport24, Aalborg, Denmark, and Aalborg
University, Denmark, are all thanked for their support in form
of grants. Copenhagen Marathon race organizers are thanked
for their kind cooperation.
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