The effects of six weeks of supplementation with multi-ingredient performance supplements and resistance training on anabolic hormones,body composition,strength,and power in resistance-trained men

Background: resistance training (rt) enhances muscle protein synthesis and hypertrophy while increasing strength and power. some multi-ingredient performance supplements (mips) have been shown to augment the physiological improvements associated with rt. the purpose of this study was to investigate the impact of specific pre- and post-workout mips on anabolic hormones,body composition,muscle strength,and power in resistance-trained men participating in a periodized rt program.methods: twenty-four ( mean ± se; 24.0 ± 0.9 years; 180.5 ± 5.8 cm; 83.7 ± 0.5 kg) resistance-trained men completed 6 wks of periodized rt (3x/wk). participants were assigned to one of two groups based upon maximal voluntary contraction of the quadriceps (biodex) to lean mass (lm) ratio. group 1 (n = 13; mips) consumed one serving of no-shotgun® (whey protein,casein protein,branched-chain amino acids,creatine,beta alanine,and caffeine) before each workout and one serving of no-synthesize® (whey protein,casein protein,branched-chain amino acids,creatine,and beta alanine; vital pharmaceuticals,inc.,davie,fl) immediately after each workout and on non-rt days. group 2 (n = 11; placebo; pla) consumed a flavor-matched isocaloric maltodextrin placebo. serum insulin-like growth factor 1,human growth hormone,testosterone,body composition (dxa),circumferences,1-repetition maximal strength (1rm) of the upper (chest press) and lower body (leg press),and anaerobic power (wingate test) were assessed before and after the intervention. statistical analysis included a 2 × 2 (group x time) anova with repeated measures. tukey lsd post hoc tests were used to examine pairwise differences. significance was set at p < 0.05. results: there was a main time effect (p = 0.035) for testosterone to increase,but no differences between groups were observed. there were no differences in the other blood hormones. group x time interactions were observed for lm (mips: pre,62.9 ± 2.1 to post,65.7 ± 2.0 vs. pla: pre,63.5 ± 2.3 to post,64.8 ± 2.5 kg; p = 0.017). only a main effect of time was noted for circumference measures. both groups increased upper and lower body 1rm strength to a similar degree. mips significantly increased peak anaerobic power (pre,932.7 ± 172.5 w vs. post,1119.2 ± 183.8 w,p = 0.002) while pla remained unchanged (pre,974.4 ± 44.1 w vs. post,1033.7 ± 48.6 w,p = 0.166).conclusion: consumption of mips during the course of a periodized rt program facilitated training-induced improvement in lm in trained males,whereas the consumption of pla did not. mips improved measures of anaerobic power while pla did not. © 2012 ormsbee et al.; licensee biomed central ltd.