Effects of Whey Protein Supplementation Pre- or Post-Resistance Training on Muscle Mass, Muscular Strength, and Functional Capacity in Pre-Conditioned Older Women: A Randomized Clinical Trial

Resistance training increases the effectiveness of dietary protein in preserving muscle mass and supporting physical function.

In older women aged 60 and above who regularly perform resistance training, taking 35 grams of whey protein either before or after the workout three times a week for 12 weeks increases muscle mass by 3.4–4.2%, improves strength by 8.1–8.3%, and reduces 10-meter walk time by 10.8–11.8% compared to a placebo, regardless of whether the protein is taken before or after training.

In older women who already engage in resistance training, taking whey protein supplements does not lead to greater improvements in walking speed compared to taking a placebo, after accounting for initial strength and muscle mass.

In older women who have already been physically active, 8 weeks of strength training increases muscle mass and strength, but more gains after that require adding whey protein to their diet.

Consuming 35 grams of hydrolyzed whey protein with 3.8 grams of leucine increases muscle protein synthesis and leads to greater gains in muscle mass and strength in older women who are already engaged in resistance training.

Older women who regularly perform resistance training and consume about 1.5 grams of protein per kilogram of body weight daily, including 35 grams of whey protein on training days, experience increases in skeletal muscle mass and strength.