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Background Probiotic Bacillus coagulans GBI-30, 6086 (BC30) has been shown to increase protein digestion in an in vitro model of the stomach and small intestine. Once active in the small intestine after germination, BC30 aids the digestion of carbohydrates and proteins. The extent to which BC30 administration may impact protein digestion and amino acid appearance in humans after protein ingestion is currently unknown. This study examined the impact of adding BC30 to a 25-g dose of milk protein concentrate on post-prandial changes in blood amino acids concentrations. Methods 14 males and 16 females (n = 30, 26.4 ± 6.5 years; 172.3 ± 10.8 cm; 78.2 ± 14.8 kg; 22.6 ± 7.2% fat) completed two supplementation protocols that each spanned two weeks separated by a washout period that lasted three weeks. Participants were instructed to track their dietary intake and ingest a daily 25-g dose of milk protein concentrate with (MPCBC30) or without (MPC) the addition of BC30. Body composition and demographics were assessed upon arrival to the laboratory. Upon ingestion of their final assigned supplemental dose, blood samples were taken at 0 (baseline), 30, 60, 90, 120, 180, and 240 min post-consumption and analyzed for amino acid concentrations. Results Arginine (p = 0.03) and Isoleucine (p = 0.05) revealed greater area-under-the curve (AUC) in MPCBC30 group compared to MPC. In addition, Arginine (p = 0.02), Serine (p = 0.01), Ornithine (p = 0.02), Methionine (p = 0.04), Glutamic Acid (p = 0.01), Phenylalanine (p = 0.05), Isoleucine (p = 0.04), Tyrosine (p = 0.02), Essential Amino Acids (p = 0.02), and Total Amino Acids (p < 0.01) all revealed significantly greater concentration maximum (CMax) in MPCBC30 compared to MPC. Finally, time to reach CMax (TMax) was significantly faster for Glutamine (p < 0.01), Citrulline (p < 0.01), Threonine (p = 0.04), Alanine (p = 0.02) in MPCBC30 when compared to MPC. Greater mean differences between groups for AUC and CMax in women when compared to the mean differences in men were found for several amino acids. Conclusion In concert with previous in vitro evidence of improved protein digestion and amino acid appearance, these results reveal that adding BC30 to protein sources such as milk protein concentrate can improve AUC, CMax, and faster TMax. Follow-up research should examine differences between gender and explore how aging can impact these outcomes. Retrospectively registered on June 11, 2020 at ClinicalTrials.gov as NCT04427020.

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Currier, BS, Harty, PS, Zabriskie, HA, Stecker, RA, Moon, JM, Jagim, AR, and Kerksick, CM. Fat-free mass index in a diverse sample of male collegiate athletes. J Strength Cond Res 33(6): 1474–1479, 2019—Fat-free mass index (FFMI) is a body composition metric that has been used to assess relative muscularity in athletes. Fat-free mass index is calculated by dividing FFM by height squared, although further height corrections through linear regression may be needed in taller individuals. This study reported height-adjusted FFMI (FFMIAdj) data in 209 male collegiate athletes from 10 sports (baseball, cross country, football, golf, ice hockey, weightlifting, rugby, swimming, track and field, and water polo) and the FFMIAdj natural upper limit for sports with sufficient sample size. The body composition of all subjects (mean ± SD; age: 20.7 ± 1.9 years, height: 182.9 ± 6.7 cm, body mass: 90.8 ± 16.8 kg, and percent body fat: 15.6 ± 5.3) was measured using dual-energy x-ray absorptiometry. Linear regression was used to adjust for height, and the FFMIAdj natural upper limit was determined by calculating the 97.5th percentile of all values. One-way analyses of variance with Games-Howell post hoc comparisons were used to determine between-sport differences. A paired-samples t-test revealed a significant difference (p < 0.001) between unadjusted and adjusted mean FFMI values. The overall mean FFMIAdj was 22.8 ± 2.8 kg·m−2. Significant between-sport differences (p < 0.001) in FFMIAdj were identified. Average FFMIAdj was highest in football athletes (24.28 ± 2.39 kg·m−2) and lowest in water polo athletes (20.68 ± 3.56 kg·m−2). The FFMIAdj upper limit was calculated for all athletes (28.32 kg·m−2), rugby (29.1 kg·m−2), and baseball (25.5 kg·m−2). This study reported FFMIAdj values in a diverse cohort of male collegiate athletes, providing data for the first time in several sports. These values can be used to guide nutritional and exercise interventions, predict athletic performance, and provide coaches with standardized information regarding the potential for further FFM accretion in male athletes.

Position-specific body composition values in female collegiate rugby union athletes. J Strength Cond Res 35(11): 3158-3163, 2021-Rugby union is a fullcontact, intermittent team sport. Anthropometric characteristics of rugby union athletes have been shown to influence suitability for a given position and affect performance. However, little anthropometric data exist in female rugby union athletes. Thus, the purpose of this study was to report position-specific anthropometric, body composition, and bone density values in female collegiate rugby union athletes and to identify between-position differences in these variables. This investigation was a cross-sectional study involving 101 female collegiate rugby union athletes, categorized as forwards and backs as well as by position (props, hookers, locks, flankers, number 8 forwards, halfback, fly-half, centers, wings, and fullbacks). Anthropometric characteristics of all athletes were measured, and body composition was assessed via dual-energy x-ray absorptiometry. Outcome variables included age, height, body mass, BMI, body fat percentage, fat mass (FM), FM index, fat-free mass (FFM), FFM index, lean soft tissue, bone mineral content, bone mineral area, and bone mineral density. Anthropometric and body composition differences between forwards and backs were identified via independent t-tests and Mann-Whitney U tests, depending on normality of the variable. Between-position differences were assessed using one-way analysis of variances (ANOVAs) with Tukey post-hoc comparisons or Welch's ANOVA with Dunnett's T3 post-hoc test. Significant differences (p , 0.014) were identified between forwards and backs for every anthropometric variable, with forwards displaying greater height (167.7 6 7.2 cm), body mass (81.5 6 15.1 kg), and body fat percentage (28.2 6 6.1%) relative to backs (164.5 6 5.1 cm; 64.5 6 7.7 kg; 21.9 6 3.7%). Likewise, significant differences were identified for every anthropometric variable between several positions (p , 0.01). Significant (p , 0.05) interposition differences were identified within the subgroup of forwards, but not within the subgroup of backs. The present investigation is the first to report position-specific anthropometric and body composition data in female collegiate rugby union athletes. The results of this study can be used by rugby union coaches for recruiting and personnel decisions, to determine a player's suitability for a given position, and to further inform training and nutritional interventions in this population.

Background Large (48-g), isonitrogenous doses of rice and whey protein have previously been shown to stimulate similar adaptations to resistance training, but the impact of consuming smaller doses has yet to be compared. We evaluated the ability of 24-g doses of rice or whey protein concentrate to augment adaptations following 8 weeks of resistance training. Methods Healthy resistance-trained males (n = 24, 32.8 ± 6.7 years, 179.3 ± 8.5 cm, 87.4 ± 8.5 kg, 27.2 ± 1.9 kg/m2, 27.8 ± 6.0% fat) were randomly assigned and matched according to fat-free mass to consume 24-g doses of rice (n = 12, Growing Naturals, LLC) or whey (n = 12, NutraBio Labs, Inc.) protein concentrate for 8 weeks while completing a standardized resistance training program. Body composition (DXA), muscular strength (one-repetition maximum [1RM]) and endurance (repetitions to fatigue [RTF] at 80% 1RM) using bench press (BP) and leg press (LP) exercises along with anaerobic capacity (Wingate) were assessed before and after the intervention. Subjects were asked to maintain regular dietary habits and record dietary intake every 2 weeks. Outcomes were assessed using 2 × 2 mixed (group x time) factorial ANOVA with repeated measures on time and independent samples t-tests using the change scores from baseline. A p-value of 0.05 and 95% confidence intervals on the changes between groups were used to determine outcomes. Results No baseline differences (p > 0.05) were found for key body composition and performance outcomes. No changes (p > 0.05) in dietary status occurred within or between groups (34 ± 4 kcal/kg/day, 3.7 ± 0.77 g/kg/day, 1.31 ± 0.28 g/kg/day, 1.87 ± 0.23 g/kg/day) throughout the study for daily relative energy (34 ± 4 kcals/kg/day), carbohydrate (3.7 ± 0.77 g/kg/day), fat (1.31 ± 0.28 g/kg/day), and protein (1.87 ± 0.23 g/kg/day) intake. Significant main effects for time were revealed for body mass (p = 0.02), total body water (p = 0.01), lean mass (p = 0.008), fat-free mass (p = 0.007), BP 1RM (p = 0.02), BP volume (p = 0.04), and LP 1RM (p = 0.01). Changes between groups were similar for body mass (− 0.88, 2.03 kg, p = 0.42), fat-free mass (− 0.68, 1.99 kg, p = 0.32), lean mass (− 0.73, 1.91 kg, p = 0.37), fat mass (− 0.48, 1.02 kg, p = 0.46), and % fat (− 0.63, 0.71%, p = 0.90). No significant between group differences were seen for BP 1RM (− 13.8, 7.1 kg, p = 0.51), LP 1RM (− 38.8, 49.6 kg, p = 0.80), BP RTF (− 2.02, 0.35 reps, p = 0.16), LP RTF (− 1.7, 3.3 reps, p = 0.50), and Wingate peak power (− 72.5, 53.4 watts, p = 0.76) following the eight-week supplementation period. Conclusions Eight weeks of daily isonitrogenous 24-g doses of rice or whey protein in combination with an eight-week resistance training program led to similar changes in body composition and performance outcomes. Retroactively registered on as NCT04411173.

Aerobic exercise and thermal stress instigate robust challenges to the immune system. Various attempts to modify or supplement the diet have been proposed to bolster the immune system responses. The purpose of this study was to identify the impact of yeast beta-glucan (Saccharomyces cerevisiae) supplementation on exercise-induced muscle damage and inflammation. Healthy, active men (29.6 ± 6.7 years, 178.1 ± 7.2 cm, 83.2 ± 11.2 kg, 49.6 ± 5.1 mL/kg/min, n = 16) and women (30.1 ± 8.9 years, 165.6 ± 4.1 cm, 66.7 ± 10.0 kg, 38.7 ± 5.8 mL/kg/min, n = 15) were randomly assigned in a double-blind and cross-over fashion to supplement for 13 days with either 250 mg/day of yeast beta-glucan (YBG) or a maltodextrin placebo (PLA). Participants arrived fasted and completed a bout of treadmill exercise at 55% peak aerobic capacity (VO2Peak) in a hot (37.2 ± 1.8 °C) and humid (45.2 ± 8.8%) environment. Prior to and 0, 2, and 72 h after completing exercise, changes in white blood cell counts, pro- and anti-inflammatory cytokines, markers of muscle damage, markers of muscle function, soreness, and profile of mood states (POMS) were assessed. In response to exercise and heat, both groups experienced significant increases in white blood cell counts, plasma creatine kinase and myoglobin, and soreness along with reductions in peak torque and total work with no between-group differences. Concentrations of serum pro-inflammatory cytokines in YBG were lower than PLA for macrophage inflammatory protein 1β (MIP-1β) (p = 0.044) and tended to be lower for interleukin 8 (IL-8) (p = 0.079), monocyte chemoattractment protein 1 (MCP-1) (p = 0.095), and tumor necrosis factor α (TNF-α) (p = 0.085). Paired samples t-tests using delta values between baseline and 72 h post-exercise revealed significant differences between groups for IL-8 (p = 0.044, 95% Confidence Interval (CI): (0.013, 0.938, d = −0.34), MCP-1 (p = 0.038, 95% CI: 0.087, 2.942, d = −0.33), and MIP-1β (p = 0.010, 95% CI: 0.13, 0.85, d = −0.33). POMS outcomes changed across time with anger scores in PLA exhibiting a sharper decline than YBG (p = 0.04). Vigor scores (p = 0.04) in YBG remained stable while scores in PLA were significantly reduced 72 h after exercise. In conclusion, a 13-day prophylactic period of supplementation with 250 mg of yeast-derived beta-glucans invoked favorable changes in cytokine markers of inflammation after completing a prolonged bout of heated treadmill exercise.

Glucosamine (GLU) is a natural compound found in cartilage, and supplementation with glucosamine has been shown to improve joint heath and has been linked to reduced mortality rates. GLU is poorly absorbed and may exhibit functional properties in the gut. The purpose of this study was to examine the impact of glucosamine on gastrointestinal function as well as changes in fecal microbiota and metabolome. Healthy males (n = 6) and females (n = 5) (33.4 ± 7.7 years, 174.1 ± 12.0 cm, 76.5 ± 12.9 kg, 25.2 ± 3.1 kg/m2, n = 11) completed two supplementation protocols that each spanned three weeks separated by a washout period that lasted two weeks. In a randomized, double-blind, placebo-controlled, crossover fashion, participants ingested a daily dose of GLU hydrochloride (3000 mg GlucosaGreen®, TSI Group Ltd., USA) or maltodextrin placebo. Study participants completed bowel habit and gastrointestinal symptoms questionnaires in addition to providing a stool sample that was analyzed for fecal microbiota and metabolome at baseline and after the completion of each supplementation period. GLU significantly reduced stomach bloating and showed a trend towards reducing constipation and hard stools. Phylogenetic diversity (Faith’s PD) and proportions of Pseudomonadaceae, Peptococcaceae, and Bacillaceae were significantly reduced following GLU consumption. GLU supplementation significantly reduced individual, total branched-chain, and total amino acid excretion, with no glucosamine being detected in any of the fecal samples. GLU had no effect on fecal short-chain fatty acids levels. GLU supplementation provided functional gut health benefits and induced fecal microbiota and metabolome changes.