Low-dose creatine supplementation enhances fatigue resistance in the absence of weight gain.
OBJECTIVE
We examined the effects of 6 wk of low-dose creatine supplementation on body composition, muscle function, and body creatine retention.


METHODS
Twenty healthy men and women (21 ± 2 y old) were randomized to receive creatine (0.03 g · kg(-1) · d(-1); n = 10, 4 women) or placebo (n = 10, 4 women) for 6 wk in a double-blind placebo-controlled fashion. Participants were tested on two occasions before supplementation to establish a reliable baseline, and then were retested after supplementation. Testing included body composition, maximal strength (three-repetition maximal concentric knee extension at 180 degrees/s), muscle fatigue (five sets of 30 concentric knee extensions at 180 degrees/s), and plasma creatine concentration.


RESULTS
There were no significant differences in body mass, fat-free mass, fat mass, body fat percentage, total body water, or maximal strength in either group from before to after supplementation (all P > 0.05). After supplementation, plasma creatine increased significantly in the creatine group (+182%, P = 0.03), with no difference in the placebo group. Compared with baseline values, creatine-supplemented volunteers were more resistant to fatigue during sets 2 (7%), 3 (9%), 4 (9%), and 5 (11%) (all P < 0.05). In placebo-supplemented participants, there was no improvement in fatigue resistance during sets 2 (0%), 3 (1%), 4 (0%), and 5 (-1%) (all P > 0.05).


CONCLUSIONS
Ingesting a low dose (≈2.3 g/d) of creatine for 6 wk significantly increased plasma creatine concentration and enhanced resistance to fatigue during repeated bouts of high-intensity contractions.
Rawson
Eric S
ES
Department of Exercise Science, Bloomsburg University, Bloomsburg, Pennsylvania, USA. erawson@bloomu.edu
Stec
Michael J
MJ
Frederickson
Sara J
SJ
Miles
Mary P
MP
D000328:Adult; D001835:Body Weight / Q000187:drug effects; D003401:Creatine / Q000097:blood / Q000494:pharmacology*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D018763:Muscle Fatigue / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000502:physiology; D055815:Young Adult
D003401:Creatine