The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available ...literature, the position of the Society is as follows:An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4-2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein.Higher protein intakes (2.3-3.1 g/kg/d) may be needed to maximize the retention of lean body mass in resistance-trained subjects during hypocaloric periods.There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass).Recommendations regarding the optimal protein intake per serving for athletes to maximize MPS are mixed and are dependent upon age and recent resistance exercise stimuli. General recommendations are 0.25 g of a high-quality protein per kg of body weight, or an absolute dose of 20-40 g.Acute protein doses should strive to contain 700-3000 mg of leucine and/or a higher relative leucine content, in addition to a balanced array of the essential amino acids (EAAs).These protein doses should ideally be evenly distributed, every 3-4 h, across the day.The optimal time period during which to ingest protein is likely a matter of individual tolerance, since benefits are derived from pre- or post-workout ingestion; however, the anabolic effect of exercise is long-lasting (at least 24 h), but likely diminishes with increasing time post-exercise.While it is possible for physically active individuals to obtain their daily protein requirements through the consumption of whole foods, supplementation is a practical way of ensuring intake of adequate protein quality and quantity, while minimizing caloric intake, particularly for athletes who typically complete high volumes of training. Rapidly digested proteins that contain high proportions of essential amino acids (EAAs) and adequate leucine, are most effective in stimulating MPS. Different types and quality of protein can affect amino acid bioavailability following protein supplementation. Athletes should consider focusing on whole food sources of protein that contain all of the EAAs (i.e., it is the EAAs that are required to stimulate MPS). Endurance athletes should focus on achieving adequate carbohydrate intake to promote optimal performance; the addition of protein may help to offset muscle damage and promote recovery. Pre-sleep casein protein intake (30-40 g) provides increases in overnight MPS and metabolic rate without influencing lipolysis.
Multi-ingredient thermogenic supplements can acutely increase resting energy expenditure (REE) and subjective energy. However, less is understood about the effects of chronic consumption on body ...composition, metabolism, and subjective variables such as mood, sleep quality, and eating behaviors. Fifty-two healthy, exercise-trained participants (50% female; mean ± SD age: 23.5 ± 3.0 years; body fat percentage: 27.3 ± 8.0%) were randomized 2:2:1 to take a whey protein supplement alone (PRO; n = 20), in combination with a thermogenic supplement (PRO + FB; n = 19), or no supplement at all (CON; n = 13) for four weeks. Body composition, anthropometric, metabolic, hemodynamic, and subjective outcomes were collected before and after the intervention. Greater changes in REE occurred in PRO + FB as compared to CON (111.2 kcal/d, 95% CI 2.4 to 219.9 kcal/d, p = 0.04), without significant differences between PRO and CON (42.7 kcal/d, 95% CI −65.0 to 150.3 kcal/d, p = 0.61) or between PRO + FB and PRO (68.5 kcal/d, 95% CI −28.3, 165.3, p = 0.21). No changes in hemodynamic outcomes (blood pressure and heart rate) were observed. In exercising adults, four weeks of supplementation with protein and a multi-ingredient thermogenic product maintained fasted REE as compared to no supplementation, for which a decrease in REE was observed, without differential effects on body composition, anthropometrics, or subjective variables.
Thermogenic supplements are often consumed by individuals seeking to improve energy levels and reduce body fat. These supplements are sold in powdered or ready-to-drink (RTD) forms and consist of a ...blend of ingredients such as caffeine, green tea extract, and other botanical compounds. While there is evidence that thermogenic supplements can positively affect resting energy expenditure (REE), the effect varies based on the combination of active ingredients. Additionally, there is some concern that thermogenic supplements may cause unwanted side effects on hemodynamic variables, like heart rate (HR) and blood pressure (BP). Therefore, further investigation into the efficacy and safety of commercially available products is warranted.
Twenty-eight individuals (14 F, 14 M; age: 23.3 ± 3.9 yrs; height: 169.4 ± 8.6 cm; body mass: 73.3 ± 13.1 kg) completed two visits in a randomized, double-blind, crossover fashion. Each visit began with baseline REE, HR, and BP assessments, which were followed by ingestion of an active RTD thermogenic beverage (RTD; OxyShred Ultra Energy) or placebo (PL). Assessments were repeated at the intervals of 35-50- and 85-100-minutes post-ingestion. In addition, subjective outcomes of energy, focus, concentration, alertness, and mood were collected five times throughout each visit. Repeated-measures analysis of variance was performed with condition and time specified as within-subjects factors and sex and resistance training (RT) status as between-subjects factors. Statistical significance was accepted at
< 0.05.
A significant condition × time interaction was observed for REE (
< 0.001). Higher REE values were demonstrated at 35-50 min (0.08 ± 0.02 kcal/min;
= 0.001; 5.2% difference) and 85-100 min (0.08 ± 0.02 kcal/min;
= 0.001; 5.5% difference) after RTD ingestion as compared to PL. No significant condition × time interactions were observed for respiratory quotient, HR, or BP. Condition main effects indicated lower HR (3.0 ± 0.9 bpm;
= 0.003), higher SBP (3.5 ± 1.1 mm Hg;
= 0.003) and higher DBP (3.5 ± 0.9 mm Hg;
< 0.001) in RTD as compared to PL, irrespective of time. Condition × time interactions were observed for all subjective outcomes (
≤ 0.02). Post hoc tests indicated statistically significant benefits of the RTD over PL for energy, focus, concentration, and alertness, without significant differences for mood after correction for multiple comparisons. Sex and RT status were not involved in interactions for any outcomes, except for a Sex × RT status interaction for energy, indicating higher energy ratings in non-resistance-trained vs. resistance-trained males.
These data suggest that acute ingestion of a thermogenic RTD beverage significantly increases REE, and this elevated caloric expenditure is sustained for at least 100 minutes following ingestion. Furthermore, the RTD beverage increased measures of energy, focus, concentration, and alertness as compared to placebo. While minor differences in hemodynamic variables were observed between conditions, all values stayed within normal ranges. Individuals aiming to increase energy expenditure may benefit from acute ingestion of an RTD thermogenic supplement.
We examined if 12 weeks of capsaicinoid (CAP) supplementation affected appetite, body composition and metabolic health markers. Seventy seven healthy male and female volunteers (30 ± 1 y, ...171.2 ± 9.8 cm, 81.0 ± 2.2 kg, 27.5 ± 0.6 kg/m2) were randomly assigned to ingest either low-dose CAP (2 mg/d; L-CAP, n = 27), high-dose CAP (4 mg/d; H-CAP, n = 22) from Capsimax or placebo (corn starch; PLA, n = 28) for 12 weeks. At baseline (0 WK), 6 weeks (6 WK) and 12 weeks (12 WK) waist: hip ratio, body composition via dual energy x-ray absorptiometry (DEXA, 0 WK and 12 WK only), self-reported Calorie intakes, appetite levels via Council on Nutrition Appetite Questionnaire (CNAQ) and serum metabolic health markers (0 WK and 12 WK only) were analyzed. Moreover, an oral glucose tolerance test (OGTT) was administered at 0 WK and 12 WK, and serum glucose and insulin responses were examined 30–120 min post test-drink consumption. Waist: hip ratio significantly decreased in L-CAP from 0 WK to 6 WK (p < 0.05), although supplementation did not significantly affect body composition. H-CAP consumed less kcal/d compared to PLA at 12 WK (difference = 257 kcal/d, p < 0.05) and L-CAP participants at 12 WK (difference = 247, p < 0.05). Twenty-three percent (9/39) of the originally-enrolled H-CAP participants reported GI distress, although no participants in the L-CAP group reported such adverse events. Interestingly, H-CAP participants presented significant increases in serum insulin as well as significant decreases in serum HDL cholesterol levels from WK0 to WK12. However, supplementation did not affect the insulin response to the administered OGTT and/or other indices of insulin sensitivity. These data suggest that H-CAP supplementation reduces self-reported energy intake after 12 weeks of supplementation, and L-CAP supplementation also reduces waist: hip ratio. Longer-term effects of capsaicinoid supplementation on basal insulin and cholesterol levels warrant further investigation.
Tracking changes in body composition may provide key information about the effectiveness of training programs for athletes. This study reports on the agreement between bioelectrical impedance ...analysis (BIA) and dual-energy X-ray absorptiometry (DXA) for tracking body composition changes during a seven-week offseason training program in 29 NCAA collegiate American football players. Body composition in subjects (mean ± SD; age: 19.7 ± 1.5 y; height: 179.8 ± 6.6 cm; body mass (BM: 96.1 ± 12.6 kg; DXA body fat: 20.9 ± 4.4%) was estimated using BIA (InBody 770) and DXA (Hologic Horizon) before and after the training intervention. Repeated measures ANOVA and post hoc comparisons were performed. Longitudinal agreement between methods was also examined by concordance correlation coefficient (CCC) and Bland-Altman analysis alongside linear regression to identify bias. Significant method by time interactions were observed for BM (DXA: 1.1 ± 2.4 kg; BIA: 1.4 ± 2.5 kg;
< 0.03), arms fat-free mass (FFM) (DXA: 0.4 ± 0.5 kg; BIA: 0.2 ± 0.4 kg;
< 0.03), and legs FFM (DXA: 0.6 ± 1.1 kg; BIA: 0.1 ± 0.6 kg;
< 0.01). Post hoc comparisons indicated that DXA-but not BIA-detected increases in FFM of the arms and legs. Time main effects, but no method by time interactions, were observed for total FFM (DXA: 1.6 ± 1.9 kg; BIA: 1.2 ± 2.1 kg;
= 0.004) and trunk FFM (DXA: 0.7 ± 1.3 kg; BIA: 0.5 ± 1.0 kg;
= 0.02). Changes in total BM (CCC = 0.96), FFM (CCC = 0.49), and fat mass (CCC = 0.50) were significantly correlated between BIA and DXA. DXA and BIA may similarly track increases in whole-body FFM in American collegiate football players; however, BIA may possess less sensitivity in detecting segmental FFM increases, particularly in the appendages.
Purpose
Quantify and compare the movement demands of gameplay in a male only and a female only touch rugby team competing in the International Touch World Cup (2019).
Methods
Movement demands (male: ...n = 16; female: n = 15) were assessed across 16 games (male open's: 8; female open's: 8) with 10 Hz global positioning system devices. Separate linear mixed models and Cohen's effect size (ES) comparisons were used to analyze variables by half (1st vs. 2nd half) and gender (male vs. female).
Results
Within game comparisons revealed reductions in run distance (ES = -0.26; p = 0.003) and worst-case scenario one-minute relative distance (ES = -0.29; p = 0.019) from the first to second half in a male only team. The female only team experienced an increase in walk distance (ES = 0.42; p <0.001) and a reduction in run distance (ES = -0.27; p <0.001) from the first to second half. Gender comparisons revealed the male only team maintained a higher average speed (ES = -0.49; p = 0.006) while covering a greater run distance (ES = -1.03; p = <0.001) and sprint distance (ES = -0.98; p < 0.001) than the female only team. The male only team also achieved a higher peak speed than the female only team (ES = -0.70; p < 0.001).
Conclusions
Movement demands of touch games remain consistent from the first to second half in male only and female only teams. However, male only games appear to be played at a higher intensity than female only games. Results from our study suggest gender specific conditioning programs should be implemented to best prepare players for international competition.
Outlaw, JJ, Smith-Ryan, AE, Buckley, AL, Urbina, SL, Hayward, S, Wingfield, HL, Campbell, B, Foster, C, Taylor, LW, and Wilborn, CD. Effects of β-alanine on body composition and performance measures ...in collegiate women. J Strength Cond Res 30(9): 2627-2637, 2016-The purpose of this study was to evaluate the effects of β-alanine (BA) supplementation and resistance training on body composition and performance. In a double-blind placebo-controlled design, 16 untrained collegiate females (mean ± SD: 21.0 ± 2.2 years; 64.8 ± 8.5 kg; 164.5 ± 7.0 cm; 30.1 ± 5.1 percent body fat %BF) completed 8 weeks of resistance training while consuming either 3.4 g BA or placebo (PL; 5 g maltodextrin) before training sessions. Training consisted of 4 days per week upper- and lower-body exercises. Lean body mass (LBM), fat mass (FM), and %BF were assessed using dual-energy x-ray absorptiometry. Maximal oxygen consumption (VCombining Dot AboveO2max), aerobic time to exhaustion, Wingate peak power, bench press and leg press 1RM (BPmax; LPmax), and repetitions at 65% (BPreps; LPreps), vertical jump (VJ), and standing broad jump were assessed using standard National Strength and Conditioning Association guidelines. All measurements were taken at baseline (T1), 4 weeks (T2), and 8 weeks (T3). Repeated-measures analysis of variance and 95% confidence intervals were used to determine significance. Body composition (LBM, FM, and %BF) improved over time (p < 0.01) for both groups. Maximal strength and VJ increased significantly from baseline to T3 (p ≤ 0.05). There was a significant interaction for LPreps (p = 0.040), with only BA group resulting in significantly greater LPreps (p = 0.041) at T2 and T3. Results from this study suggest that 8 weeks, 4 days per week progressive resistance training and BA supplementation may be effective for improving lower-body muscular endurance. β-alanine had no additive effects on body composition or maximal strength in collegiate women.
Two of the most popular forms of protein on the market are whey and casein. Both proteins are derived from milk but each protein differs in absorption rate and bioavailability, thus it is possible ...that each type of protein may contribute differently to the adaptations elicited through resistance training. Therefore, the purpose of this study was to investigate the potential effects of ingestion of two types of protein in conjunction with a controlled resistance training program in collegiate female basketball players. Sixteen NCAA Division III female basketball players were matched according to body mass and randomly assigned in a double-blind manner to consume 24 g whey protein (WP) (N = 8, 20.0 ± 1.9 years, 1.58 ± 0.27 m, 66. 0 ± 4.9 kg, 27.0 ± 4.9 %BF) or 24 g casein protein (CP) (N = 8, 21.0 ± 2.8 years, 1.53 ± 0.29 m, 68.0 ± 2.9 kg, 25.0 ± 5.7 %BF) immediately pre- and post-exercise for eight weeks. Subjects participated in a supervised 4-day per week undulating periodized training program. At 0 and 8 weeks, subjects underwent DXA body composition analysis, and at 0 and 8 weeks underwent one repetition maximum (1RM) strength, muscle endurance, vertical jump, 5-10-5 agility run, and broad jump testing sessions. Data were analyzed using repeated measures ANOVA, and presented as mean ± SD changes from baseline after 60 days. No significant group x time interaction effects were observed among groups in changes in any variable (p > 0.05). A significant time effect was observed for body fat (WP: -2.0 ± 1.1 %BF; CP: -1.0 ± 1.6 %BF, p < 0.001), lean mass (WP: 1.5 ± 1.0 kg; CP: 1. 4 ± 1.0 kg, p < 0.001), fat mass (WP: -1.3 ± 1.2 kg; CP: -0.6 ± 1.4 kg, p < 0.001), leg press 1RM (WP: 88.7 ± 43.9 kg; CP: 90.0 ± 48.5 kg, p < 0.001), bench press 1RM (WP: 7.5 ± 4.6 kg; CP: 4.3 ± 4.5 kg, p = 0.01), vertical jump (WP: 4.1 ± 1.8 cm; CP: 3.5 ± 7.6 cm, p < 0.001), 5-10-5 (WP: -0.3 ± 0.2 sec; CP: -0.09 ± 0.42 sec, p < 0.001), and broad jump (WP: 10.4 ± 6.6 cm; CP: 12. 9 ± 7.1 cm, p < 0.001). The combination of a controlled undulating resistance training program with pre- and post-exercise protein supplementation is capable of inducing significant changes in performance and body composition. There does not appear to be a difference in the performance- enhancing effects between whey and casein proteins. Key pointsFemales can experience and increase in performance makers from consuming protein after resistance training.Females can have a decreased body fat composition when ingesting protein with daily resistance training and conditioning.There was no significant difference in performance markers between whey and casein.
Extracellular signal-regulated kinase (ERK) 1/2 signaling has been shown to be increased after heavy resistance exercise and suggested to play a role in the hypertrophic adaptations that are known to ...occur with training. However, the role that ERK1/2 may play in response to lower intensities of resistance exercise is unknown. Therefore, the purpose of this study was to determine the effects of resistance exercise intensity on ERK1/2 activity in human skeletal muscle. Twelve recreationally active men completed separate bouts of single-legged resistance exercise with 8-10 repetitions (reps) at 80-85% 1 repetition maximum (1RM) (85%) and 18-20 reps at 60-65% 1RM (65%) in a randomized crossover fashion. For both resistance exercise sessions, vastus lateralis biopsies and blood draws were taken immediately before exercise (PRE) and at 30 minutes (30MPST), 2 hours (2HRPST), and 6 hours (6HRPST) post exercise, with an additional blood draw occurring immediately after exercise (POST). The phosphorylated levels of pIGF-1R, pMEK1, pERK1/2, and activated Elk-1 were assessed by phosphoELISA, and serum insulin-like growth factor 1 (IGF-1) was assessed via enzyme-linked immunosorbent assay. Statistical analyses used a 2 × 4 (muscle responses) and 2 × 5 (serum responses) multivariate analysis of variance on delta values from baseline (p < 0.05). Both exercise intensities significantly increased the activity of insulin-like growth factor 1 receptor (IGF-1R), mitogen-activated protein kinase 1, ERK1/2, and Elk-1, with peak activity occurring at 2HRPST (p < 0.001). However, 65% resulted in a preferential increase in IGF-1R and Elk-1 activation when compared with 85% (p < 0.05). No differences were observed for serum IGF-1 levels regardless of intensity and time. These findings demonstrate that resistance exercise upregulates ERK1/2 signaling in a manner that does not appear to be preferentially dependent on exercise intensity.
Capsaicinoids (CAPs) found in chili peppers and pepper extracts, are responsible for enhanced metabolism. The objective of the study was to evaluate the effects of CAPs on body fat and fat mass while ...considering interactions with body habitus, diet and metabolic propensity.
Seventy-five (
= 75) volunteer (male and female, age: 18 and 56 years) healthy subjects were recruited. This is a parallel group, randomized, double-blind, placebo controlled exploratory study. Subjects were randomly assigned to receive either placebo, 2 mg CAPs or 4 mg CAPs dosing for 12 weeks. After initial screening, subjects were evaluated with respect to fat mass and percent body fat at baseline and immediately following a 12-week treatment period. The current study evaluates two measures of fat loss while considering six baseline variables related to fat loss. Baseline measurements of importance in this paper are those used to evaluate body habitus, diet, and metabolic propensity. Lean mass and fat mass (body habitus); protein intake, fat intake and carbohydrate intake; and total serum cholesterol level (metabolic propensity) were assessed. Body fat and fat mass were respectively re-expressed as percent change in body fat and change in fat mass by application of formula outcome = (12-week value - baseline value) / baseline value) × 100. Thus, percent change in body fat and change in fat mass served as dependent variables in the evaluation of CAPs. Inferential statistical tests were derived from the model to compare low dose CAPs to placebo and high dose CAPs to placebo.
Percent change in body fat after 12 weeks of treatment was 5.91 percentage units lower in CAPs 4 mg subjects than placebo subjects after adjustment for covariates (
= 0.0402). Percent change in fat mass after 12 weeks of treatment was 6.68 percentage units lower in Caps 4 mg subjects than placebo subjects after adjustment for covariates (
= 0.0487).
These results suggest potential benefits of Capsaicinoids (CAPs) on body fat and fat mass in post hoc analysis. Further studies are required to explore pharmacological, physiological, and metabolic benefits of both chronic and acute Capsaicinoids consumption.
ISRCTN10458693 'retrospectively registered'.
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