Effects of 28 days of resistance exercise and consuming a commercially available pre-workout supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers in males

This study determined the effects of 28 days of heavy resistance exercise combined with the nutritional supplement, NO-Shotgun(R) on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers

Body Composition Estimation and Satisfaction in College Students

College students are at an elevated risk for engaging in unhealthy lifestyle behaviors, including disordered eating and low levels of exercise. Evidence also suggests that college students inaccurately estimate their weight status (e.g., reporting they are overweight when they are at a normal weight) and report high levels of body dissatisfaction. Efforts to promote healthy behavior change and body satisfaction first require an accurate perception of the problem. The purpose of this study was to 1) determine the accuracy with which college students estimate their weight and body composition, and 2) better understand the relationship between body composition and body satisfaction. Methods: Forty-five college students (males = 21 and females = 24), between 18 and 30 years of age, completed a survey with items assessing demographic characteristics, weight status estimation, body composition estimation, and the Body Part Satisfaction Scale (BPSS). Body composition was assessed using Dual x-ray absorptiometry (DXA). Paired samples t-tests were used to compare means between participant’s objective measurements and their estimated measurements. Bivariate analyses were used to determine relationships between body part dissatisfaction and body composition. Results: Males and females accurately estimated their weight (d =-.16, SD = 2.56, t(44) = -.414, p = 0.68), but significantly underestimated their body fat percentage (d =-4.37, SD = 7.62, t(44) = -3.85), p = 0.001). Greater body dissatisfaction was associated with a higher body fat percentage (r =. 353), but not body fat percentage estimation (r = .164). In the trunk region, a higher body fat percentage in that region was significantly associated with greater dissatisfaction for abdomen size (r = .323); higher body fat percentage in the arms and legs were mildly associated with greater dissatisfaction in the respective areas (r = .268; r = .260), though not statistically significant. Conclusions: Although college students accurately estimated their weight, they significantly underestimated their fat mass, indicating a misunderstanding regarding the proportion of their body weight composed of fat tissue. As expected, greater fat mass in specific body parts (e.g., arms, legs, and truck) was related with greater dissatisfaction in those specific areas. Future research should continue to investigate these relationships and body composition estimation accuracy in more diverse samples. Health promotion initiatives should aim to educate students on body composition and continue to promote healthy behavior change along with body satisfaction

Effects of Capsaicin and Evodiamine Ingestion on Energy Expenditure and Fat Oxidation at Rest and After Moderately-Intense Exercise in Young Men

Capsaicin and evodiamine are two thermogenic agents each recognized for their ability to stimulate the sympathetic nervous system and are thus found in many dietary supplements. Therefore, the purpose of this study was to observe the effects that capsaicin and evodiamine have on hemodynamics, energy expenditure, and markers of lipid oxidation while at rest and after a single bout of moderate-intensity exercise in young men. In a randomized, cross-over design, 11 men orally ingested 500 mg of capsaicin, evodiamine, or placebo while at rest after 30 minutes of resting energy expenditure assessment using open-circuit spirometry. After an additional 30 minutes of rest after supplement ingestion, resting energy expenditure was assessed again for 30 minutes. After the second resting energy expenditure assessment, treadmill exercise was performed until expending approximately 500 kilocalories (~30 minutes) at 65% peak oxygen consumption. Energy expenditure was assessed for another 30 minutes into the post-exercise period. Heart rate and blood pressure, core temperature, and venous blood samples were obtained 30 minutes before and one hour after supplement ingestion (i.e. immediately pre-exercise), and immediately after and 45 minutes post-exercise. Markers of lipid oxidation (serum glycerol, free fatty acids, serum glucose, epinephrine, and norepinephrine) were determined spectrophotometrically and with ELISA. Two-way analyses of variance (ANOVA) were performed for each dependent variable (p ≤ 0.05). Significant main effects for Time existed for hemodynamics, energy expenditure, serum catecholamines and markers of fat oxidation immediately following exercise (p \u3c 0.05). However, no significant Supplement x Time interactions were noted for any criterion variable (p \u3e 0.05), suggesting no preferential difference between supplements. Neither capsaicin nor evodiamine, at a single dose of 500 mg, are effective at inducing thermogenesis and increasing fat oxidation at rest or during exercise in young men

A Comparison of Flexed Vs. Relaxed Skinfold Methodology in College Aged Males and Females

Skinfold caliper measurements are routinely utilized in assessing individual’s body composition and subcutaneous fat thicknesses. The precise separation of subcutaneous fat from muscle is critical to obtaining accurate measurements of body composition. The current investigation examined the accuracy of a flexed skinfold method (FSM) compared to the traditional relaxed skinfold method (RSF) and DEXA in 20 males (mean age = 20.8 + 2.5 yrs) and 20 females (mean age = 20.8 + 1.6 yrs). Body composition was assessed by FSM and RSF in a counterbalanced design within gender for RSF and FSM, using Lange skinfold calipers with the Jackson-Pollock 3-site method and the Siri’s percent body fat equation. Each site (chest, umbilical, and thigh for males; triceps, super iliac, and thigh for females) was measured three times and the average was utilized to calculate body density and percent body fat. The same researcher performed all skinfold measurements and DEXA scan on a single occasion. A 2 X 3 ANOVA was used to determine the effect of gender (females and males) and different body composition methods (FSM, RSM, and DEXA) along with Bland-Altman plots. No statistical differences were observed between FSM and RSM in body fat percentage (FSM: 15.7 + 7.5% vs. RSM: 16.0 + 7.5%; p = 0.74), chest (FSM: 4.3 + 1.2mm vs. RSM: 4.6 + 1.6mm; p = 0.83), triceps (FSM: 18.7 + 6.1mm vs. RSM: 18.6 + 5.4mm; p = 0.52), super iliac (FSM: 15.2 + 4.3mm vs. RSM: 15.1 + 4.8mm; p = 0.62), or umbilical measurement (FSM: 17.1 + 6.3mm vs. RSM: 17.3 + 6.2mm; p = 0.62). However, there was a significant difference in thigh skinfold location, indicating that subcutaneous fat measured by FSM was lower than one measured by RSM (FL: 17.5 + 7.2mm, RL: 18.5 + 7.4mm; p = 0.003). Additionally, both FSM and RSM underestimated body fat percentage as compared to DEXA (FSM: 15.7 + 7.5%, RSM: 16.0 + 7.5%, vs. DEXA: 18.9 + 7.5%; p \u3c 0.01). It appears that assessing overall body composition using a flexed skinfold method does not necessarily improve the overall accuracy of skinfold body composition measurement when compared against a relaxed method

Nutrient Administration and Resistance Training

Skeletal muscle tissue is tightly regulated throughout our bodies by balancing its synthesis and breakdown. Many factors are known to exist that cause profound changes on the overall status of skeletal muscle, some of which include exercise, nutrition, hormonal influences and disease. Muscle hypertrophy results when protein synthesis is greater than protein breakdown. Resistance training is a popular form of exercise that has been shown to increase muscular strength and muscular hypertrophy. In general, resistance training causes a stimulation of protein synthesis as well as an increase in protein breakdown, resulting in a negative balance of protein. Providing nutrients, specifically amino acids, helps to stimulate protein synthesis and improve the overall net balance of protein. Strategies to increase the concentration and availability of amino acids after resistance exercise are of great interest and have been shown to effectively increase overall protein synthesis. [1-3] After exercise, providing carbohydrate has been shown to mildly stimulate protein synthesis while addition of free amino acids prior to and after exercise, specifically essential amino acids, causes a rapid pronounced increase in protein synthesis as well as protein balance.[1,3] Evidence exists for a dose-response relationship of infused amino acids while no specific regimen exists for optimal dosing upon ingestion. Ingestion of whole or intact protein sources (e.g., protein powders, meal-replacements) has been shown to cause similar improvements in protein balance after resistance exercise when compared to free amino acid supplements. Future research should seek to determine optimal dosing of ingested intact amino acids in addition to identifying the cellular mechanistic machinery (e.g. transcriptional and translational mechanisms) for causing the increase in protein synthesis

ISSN exercise & sport nutrition review: research & recommendations

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients

Exercise Prescription: A Case Study Approach to the ACSM Guidelines

You will find no better preparation source for the American College of Sports Medicine (ACSM) certification than the new, second edition of Exercise Prescription: A Case Study Approach to the ACSM Guidelines. Authors David Swain and Brian Leutholtz present a series of case studies to help you translate the ACSM guidelines for exercise prescription into practical knowledge. [From the Publisher]https://digitalcommons.odu.edu/hms_books/1005/thumbnail.jp