Low-dose creatine supplementation enhances fatigue resistance in the absence of weight gain.
Study Goal
The researchers aimed to examine the effects of low-dose creatine supplementation on body composition, muscle function, and body creatine retention.
Results Summary
The study found no significant changes in body composition or maximal strength, but creatine supplementation increased plasma creatine levels and improved resistance to muscle fatigue during high-intensity contractions.
Population
Twenty healthy men and women (21 ± 2 years old).
Effective Dosage
0.03 g/kg/day (≈2.3 g/day).
Duration
6 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
low-dose creatine supplementation | no change | body mass | healthy men and women | - | no significant differences | #1 |
low-dose creatine supplementation | no change | fat-free mass | healthy men and women | - | no significant differences | #2 |
low-dose creatine supplementation | no change | fat mass | healthy men and women | - | no significant differences | #3 |
low-dose creatine supplementation | no change | body fat percentage | healthy men and women | - | no significant differences | #4 |
low-dose creatine supplementation | no change | total body water | healthy men and women | - | no significant differences | #5 |
low-dose creatine supplementation | no change | maximal strength | healthy men and women | - | no significant differences | #6 |
low-dose creatine supplementation | increase | plasma creatine concentration | creatine-supplemented volunteers | +182% | increased significantly | #7 |
low-dose creatine supplementation | increase | fatigue resistance during set 2 | creatine-supplemented volunteers | 7% | more resistant to fatigue | #8 |
low-dose creatine supplementation | increase | fatigue resistance during set 3 | creatine-supplemented volunteers | 9% | more resistant to fatigue | #9 |
low-dose creatine supplementation | increase | fatigue resistance during set 4 | creatine-supplemented volunteers | 9% | more resistant to fatigue | #10 |
low-dose creatine supplementation | increase | fatigue resistance during set 5 | creatine-supplemented volunteers | 11% | more resistant to fatigue | #11 |
placebo | no change | plasma creatine concentration | placebo-supplemented participants | - | no difference | #12 |
placebo | no change | fatigue resistance during set 2 | placebo-supplemented participants | 0% | no improvement | #13 |
placebo | no change | fatigue resistance during set 3 | placebo-supplemented participants | 1% | no improvement | #14 |
placebo | no change | fatigue resistance during set 4 | placebo-supplemented participants | 0% | no improvement | #15 |
placebo | decrease | fatigue resistance during set 5 | placebo-supplemented participants | -1% | no improvement | #16 |
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). CONCLUSION: 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.