| The effects of oral creatine supplementation on muscle
phosphocreatine (PCr) concentration, muscle strength, and body
composition were investigated in young female volunteers (n = 19)
during 10 wk of resistance training (3 h/wk). Compared with placebo,
4 days of high-dose creatine intake (20 g/day) increased (P < 0.05)
muscle PCr concentration by 6%. Thereafter, this increase was
maintained during 10 wk of training associated with low-dose creatine
intake (5 g/day). Compared with placebo, maximal strength of the
muscle groups trained, maximal intermittent exercise capacity of the
arm flexors, and fat-free mass were increased 20-25, 10-25, and 60%
more (P < 0. 05), respectively, during creatine supplementation.
Muscle PCr and strength, intermittent exercise capacity, and fat-free
mass subsequently remained at a higher level in the creatine group
than in the placebo group during 10 wk of detraining while low-dose
creatine was continued. Finally, on cessation of creatine intake,
muscle PCr in the creatine group returned to normal within 4 wk. It
is concluded that long-term creatine supplementation enhances the
progress of muscle strength during resistance training in sedentary
females.
|