Beta-hydroxy-beta-methylbutyrate (HMB) has been used extensively as a dietary supplement for athletes and physically active people. HMB is a leucine metabolite, which is one of three branched chain amino acids. HMB plays multiple roles in the human body of which most important ones include protein metabolism, insulin activity and skeletal muscle hypertrophy. The ergogenic effects of HMB supplementation are related to the enhancement of sarcolemma integrity, inhibition of protein degradation (ubiquitin pathway), decreased cell apoptosis, increased protein synthesis (mTOR pathway), stimulation of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and enhancement of muscle stem cells proliferation and differentiation. HMB supplementation has been carried out with various groups of athletes. In endurance and martial arts athletes, HMB supplementation revealed positive effects on specific aerobic capacity variables. Positive results were also disclosed in resistance trained athletes, where changes in strength, body fat and muscle mass as well as anaerobic performance and power output were observed. The purpose of this review was to present the main mechanisms of HMB action, especially related to muscle protein synthesis and degradation, and ergogenic effects on different types of sports and physical activities.

The aim of this study was to evaluate the influence of natural sun exposure and six weeks of a high dose of vitamin D supplementation on vitamin D, testosterone and cortisol serum concentrations as well as speed, power and VO2max in professional soccer players. Materials: The study was conducted from January to September. At the beginning of the study, 33 professional soccer players were enrolled; however, only 28 subjects (height 181.5 cm; body mass 77.81 ± 8.8 kg; body fat 12.38% ± 2.4% and muscle mass 40.27 ± 5.3 kg) completed the study. The research consisted of three stages. The first one, lasting 10 days, was conducted in January during a training camp in the south part of Cyprus at a latitude of 34 33°, where participants experienced natural sun exposure; it was called a winter sun exposure (WSE) period. The second stage, which was a supplementation period (SP), lasted 6 weeks, during which all subjects were randomly assigned either to an experimental group—EG (n = 15)—or a placebo group—PG (n = 13)—and were administered 6000 IU/d cholecalciferol or a placebo, respectively. The third stage took place in September, after summertime (summer sun exposure—SSE). The data of the 25(OH)D, free and total testosterone (fT, tT), cortisol as well as 5 and 30 m sprint tests (STs), power of the left leg (PLL) and VO2max were evaluated before and after the WSE period, the SP and SSE. Results: In January, the baseline value of vitamin D in 12 subjects was ≤20 ng/mL, and 14 of them had levels between 20–30 ng/mL and 2 individuals >30 ng/mL. After the WSE period, significant changes in 25(OH)D, fT, tT and cortisol concentration, as well as in the 5 m ST, were observed. After the SP, in the EG, significant changes were found in 25(OH)D, fT, tT and the 5 m ST. Furthermore, a positive correlation between the concentration of 25(OH) fT and tT was observed. After SSE, 2 out of 28 players had <20 ng/mL 25(OH)D, 12 of them had 25(OH)D between 20 and 30 ng/mL and 14 of them had 25(OH)D between 30 and 50 ng/mL. Significant differences in 25(OH)D, fT, tT concentration and the 5 m ST performance were observed following SSE compared with the WSE period. Conclusion: Due to the serum level of 25(OH)D demonstrated by most participants at the beginning of the study and after summertime, all-year-round supplementation with high doses of vitamin D seems to be a reasonable solution to enhance high 25(OH)D concentration in blood and physical performance. In the middle of the winter, almost half of the soccer players were serum deficient of 25(OH)D. After ten days of sun exposure and 6 weeks of vitamin D supplementation, the concentration of 25(OH)D significantly increased, as did testosterone and results in the 5 m sprint test also improved. Therefore, athletes should be constantly monitored for serum levels of 25(OH)D throughout the year and should be supplemented if deficiencies or insufficient amounts of this vitamin occur.

Background: Supplementing β-alanine (BA) improves exercise performance in efforts that are highly dependent on anaerobic glycolysis. As it has not yet been established whether it relates to climbing, the current study aimed to investigate the effects of BA on climbing-specific performance. Methods: Fifteen elite climbers performed intermittent high-force high-velocity campus board exercise, and two bouldering traverses, hard and easy. They ingested 4.0 g·d−1 BA or placebo for four weeks in a double-blind, pre/post experimental design. Results: In the campus board trial, ANOVA revealed a tendency toward significance (p = 0.066). Post hoc analysis revealed that there was a significant (p = 0.002) and “large” (d = 1.55) increase in the total number of “slaps” in the BA group. No significant supplementation × group interaction was found in “hard” traverse and a significant interaction for mean changes in number of moves (p = 0.025) and in time to failure (p = 0.044) on an “easy” traverse. Post hoc analysis revealed that only the BA group significantly improved from baseline in number of moves (+9.5) and time to failure (+32 s). Effect sizes were d = 1.73 and d = 1.44, respectively. Conclusions: Four weeks of BA supplementation can improve performance during continuous climbing lasting about 1 min and repeated bouts of upper body campus-like movements. However, it failed to enhance climbing of a shorter duration.

Pre-exercise caffeine and guarana-based multi-ingredient supplement (MS) consumption may be more effective for physical performance improvement than caffeine and guarana alone due to the synergistic effect of biologically active ingredients in multi-ingredient supplements. This study aimed to examine the acute effect of MS on the reactive agility and jump performance in recreational handball male players. A randomized, double-blind, crossover study involved twenty-four male handball players (body mass 74.6 ± 8.8 kg; body height 179 ± 7 cm; age 23.8 ± 1.4 years). Participants were tested under three conditions: placebo, caffeine + guarana (CAF + GUA), or MS ingestion 45 min before exercise tests. Participants performed a reactive agility test (Y-shaped test) and countermovement jump (CMJ). None of the supplements improved countermovement jump height (p = 0.06). The time needed to complete the agility test was significantly (p = 0.02) shorter in the MS condition than in the placebo. The differences in agility between PL vs. CAF + GUA and MS vs. CAF + GUA conditions were not statistically significant (p = 0.88 and p = 0.07, respectively). The results of this study indicate that the caffeine-based multi-ingredient performance was effective in improvement in reactive agility but not in jump height in recreational handball male players. A similar effect was not observed with CAF + GUA ingestion alone.

Background: The purpose of this research was to investigate the acute effects of a pre-workout supplement on anaerobic performance in resistance-trained men. Methods: Twenty-three men underwent three randomized, double-blind testing sessions separated by a seven-day break. The participants performed three tests: isokinetic strength, three repetition maximum (3-RM) strength and Wingate. Statistical analysis was conducted in R environment. Linear mixed models were estimated via R package lme4. Results: Mean T@0.2 s was significantly greater in supplemented condition for right and left knee flexors (PL: 103.2 ± 37.6 Nm; supplemented condition: 131.8 ± 29.3 Nm (p = 0.001)), and PL: 103.7 ± 39.3; supplemented condition: 129.4 ± 28.4 (p = 0.001)). T@0.2 s for right and left knee extensors (PL: 202.6 ± 58.6 Nm; supplemented condition: 237.2 ± 54.7 Nm (p = 0.001); PL: 203.3 ± 63.2 Nm, supplemented condition: 229.8 ± 50.8 Nm (p = 0.002)). Significant difference was in mean anaerobic power between supplemented and PL condition for right and left knee flexors (p = 0.002, p = 0.005) and for right and left knee extensors (p = 0.001 and p = 0.002). TTP was significantly shorter in supplemented condition for both sides knee flexors (p = 0.002). There was a significant difference for mean power in the Wingate test (placebo: 8.5 ± 0.6 W/kg; supplemented condition: 8.7 ± 0.5 W/kg (p = 0.038)). Mean 3-RM was significantly greater in supplemented condition (p = 0.001). Conclusions: The supplement significantly improves upper and lower body strength and power output in resistance-trained men.

Introduction. Competitive and rock climbers primarily rely on anaerobic energy metabolism, and acidosis may limit their performance. It is supposed that supplements that improve buffering capacities of the body, like β-alanine (BA) and sodium bicarbonate/citrate (SB/SC), may be useful in this sport. The aim of the study was to explore the efficacy of co-supplementation of BA and SC on climbing performance. Material and methods. 13 climbers (age 40.2 ±7.9 years, height 175.4 ±8.4 cm, body mass 68.6 ±13.9 kg, UIAA metric 9.2 ±0.8) were randomly assigned to the supplement (SG; n = 7) or control group (CG: n = 6). For 4 wks, the SG was taking a supplement containing: BA 4 g·d, SC 0.6 g·d and histidine 0.2 g·d. Climbers were tested on two bouldering circuits done back and forth until exhaustion: “hard” and “easy”. Results. Climbers from the SG significantly increased their performance in terms of the number of moves done in both circuits, hard F(1,11) = 5.44, p = 0.04, ɳ2 = 0.33 and easy F(1,11) = 4.91, p = 0.05, ɳ2 = 0.33. Within group effect sizes were d = 0.49 and 0.46 for SG and 0.18 and 0.27 for CG, respectively. Conclusions. Co supplementation of BA and SC may improve performance in climbing, especially efforts lasting at least about one minute of continuous effort.

Background: The purpose of this study was to investigate the acute effects of commercially available pre-workout supplement on anaerobic performance in resistance trained men.Methods: Twenty-three men underwent three testing sessions administrated in a randomized and double-blind fashion separated by a seven-day break. The participants performed three exercise tests: isokinetic strength test, maximal strength test and Wingate test. Statistical analysis was conducted in R environment. Linear mixed models were estimated via R package lme4.Results: The mean knee peak torque was significantly greater in supplemented group for right and left knee flexors (placebo: 103.17 ± 37.61 Nm, and supplemented group: 131.84 ± 29.31 Nm where p=0.001, and placebo: 103.72 ± 39.35, and supplemented group: 129.38 ± 28.44, where p=0.001; respectively) as well as for right and left knee extensors (placebo: 202.65 ± 58.64 Nm, and supplemented group: 237.22 ± 54.75 Nm where p=0.001, and placebo: 203.27 ± 63.2 Nm versus supplemented group: 229.84 ± 50.8 Nm where p=0.002; respectively).The significant difference was observed in mean anaerobic power between supplemented and placebo group for right and left knee flexors (p=0.002 and p=0.005, respectively) as well as for right and left knee extensors (p=0.001 and p=0.002; respectively).There was also observed that the time to peak torque was significantly greater in supplemented group for right and left knee flexors (p=0.002 for both legs). The significant difference was also observed in mean power between supplemented and placebo group during Wingate test (placebo: 8.49 ± 0.57 W/kg, and supplemented group: 8.66 ± 0.55 W/kg where p=0.038). Moreover the mean 3-RM strength test was significantly greater in supplemented group with p=0.001.Conclusions: The results of the study indicate that the supplement significantly improves upper and lower body strength and power output in resistance trained men.

BackgroundThe purpose of this investigation was to examine the acute effects of a commercially available multi-ingredient performance supplement (MIPS) in comparison to caffeine, on reactive agility and jump height, in recreationally-trained handball male players. MethodsThe study followed a randomized double-blind, crossover design. Twenty-four individuals were treated with placebo, caffeine or multi-ingredient performance supplement (MIPS). Dosage of caffeine in caffeine supplement and MIPS contain the same amounts of caffeine for each subject (5 mg/kg) . All subjects attended a familiarization session 1 week before testing. Participants underwent reactive agility test (Y-test: 1-1-2 test) on three separate days with 72 h apart between test days. Just after accomplishing of each repetition of reactive agility tests participants were asked to perform countermovement jump (CMJ; 2 repetitions separated by one minute break) to establish the average height of jump, that is directly related to lower body power. To assess the significance of differences between the groups studied, Friedmann ANOVA test was used, the chi-square value (χ2) calculated and the p value of statistical significance estimated. ResultsThe research indicated significant inter-group differences in 1-1-2 agility test (p=0.04). The time was significantly shorter for MIPS supplement group in comparison to placebo (-3.4%; p=0.02) and to caffeine (-2.8%; p=0.004) group. Significant improvements (p<0.01) were observed in jump height for MIPS supplement group in comparison to placebo (+5.2%; p=0.001) and caffeine (+5.1%; p=0.001) groups, but not in caffeine to placebo comparison (p=0.84). ConclusionsThe results of these study may contribute to the assessment of the usefulness of multi-ingredient performance type supplementation in comparison to the ingestion of identical amounts of caffeine only in enhancing reactive agility and jump performance.