CREATINE SUPPLEMENTATION INCREASES REPEATED BOUT RESISTANCE EXERCISE PERFORMANCE
Stec, M. J., Miles, M. P., & Rawson, E. S. (June 03, 2010). Low-dose creatine supplementation enhances fatigue resistance in the absence of weight gain. Presentation 1918 at the 2010 Annual Meeting of the American College of Sports Medicine, Baltimore, Maryland; June 2-5.
This study examined the effects of six weeks of low-dose creatine supplementation on body composition, muscle function, and body creatine retention in non-vegetarian men and women. Ss were assigned to creatine (0.03 g/kg/d; M = 6; F = 4) or placebo (M = 6; F = 4) groups for six weeks. Ss were tested on two occasions pre-supplementation to establish a baseline, and then retested post-supplementation. Testing included: body composition, maximal strength (3 RM concentric knee extension at 180°/sec), muscle fatigue (5 x 30 concentric knee extensions at 180°/sec), and plasma creatine concentration.
There were no significant differences between the groups for body mass, fat free mass, fat mass, % body fat, total body water, or maximal strength from pre- to post-supplementation. Following supplementation, plasma creatine increased significantly only in the creatine group. There was a significant effect of sets and a significant group by set interaction in the analysis of knee extensor fatigue indicating that muscle fatigue increased across sets and that fatigue was different between groups. Relative to baseline values, creatine supplemented volunteers were significantly more resistant to fatigue during sets two through five.
Implication. Ingesting a low dose (2.3g/d) of creatine for six weeks significantly increases plasma creatine concentration and enhances resistance to fatigue during repeated bouts of high-intensity contractions.