Creatine supplementation and resistance training in vulnerable older women: A randomized double-blind placebo-controlled clinical trial

Abstract

This study aimed to examine the efficacy of creatine supplementation, associated or not with resistance training, in vulnerable older women. A 24-week, double-blind, randomized, placebo-controlled trial was performed. Sixty subjects were assigned to compose the following groups: placebo (PL), creatine supplementation (CR), placebo with resistance training (PL+RT), and creatine supplementation with resistance training (CR+RT). The subjects were assessed at baseline and after 24weeks. The primary outcome was muscle strength, as assessed by one-repetition maximum (1-RM) tests. Secondary outcomes included appendicular lean mass, bone mass, biochemical bone markers, and physical function tests. The changes in 1-RM leg press were significantly greater in the CR+RT group (+19.9%) than in the PL (+2.4%) and the CR groups (+3.7%), but not than in the PL+RT group (+15%) (p=0.002, p=0.002, and p=0.357, respectively). The CR+RT group showed superior gains in 1-RM bench press (+10%) when compared with all the other groups (p≤0.05). The CR+RT group (+1.31%) showed greater appendicular lean mass accrual than the PL (−1.2%), the CR (+0.3%), and the PL+RT groups (−0.2%) (p≤0.05). The CR and the PL+RT groups experienced comparable gains in appendicular lean mass (p=0.62), but superior to those seen in the PL group. Changes in fat mass, bone mass and serum bone markers did not significantly differ between the groups (p>0.05). In conclusion, creatine supplementation combined with resistance training improved appendicular lean mass and muscle function, but not bone mass, in older vulnerable women. Clinicaltrials.gov: NCT01472393.