In postmenopausal women, supplementation with creatine monohydrate at doses of 5 grams or higher combined with resistance training increases leg press one-repetition maximum strength by approximately 7.5 kilograms compared to placebo over a period of 12 to 104 weeks.

Creatine fills muscle cells with a special energy molecule that lets muscles produce force faster and longer during hard exercise. This allows people to lift heavier weights or do more reps, which stresses the muscles just enough to make them grow bigger and stronger. At the same time, the nervous system gets better at turning on more muscle fibers at once, so even without bigger muscles, the body can push harder. Together, these changes make the leg press strength go up by about 7.5 kilograms.