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

•Creatine with resistance training improved muscle function in vulnerable older women.•Creatine with resistance training also increased lean mass in this population.•Whether or not creatine can improve bone mass remains to be elucidated.

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 24 weeks. 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.