Abstract
To evaluate the effectiveness of a 24-week program of nutritional supplementation using whey protein ingested after resistance exercise, on increasing muscle mass and physical function among elderly with sarcopenia. We carried out a randomized controlled pilot trial, in elderly with sarcopenia, aged 65-years of age or older, allocated to three groups of participants each: the exercise and whey protein supplementation group, the exercise group, and the whey protein supplementation group. A stratified randomization strategy was used for group allocation to achieve a comparable age and sex distribution among the groups. Sarcopenia was defined using the Asian Working Group for sarcopenia criteria, as follows: low hand grip strength or slow gait speed, and low skeletal muscle mass index. A 24-week program of resistance exercise, carried out twice per week, was combined with whey protein supplementation, containing 11.0 g of protein and 2,300 mg of leucine. The nutrition intake for participants in all three experimental groups was adjusted to a level of at least 30.0 kcal/ kg ideal body weight/day of total energy intake, 1.2 g/kg ideal body weight/day of protein intake, and more during the intervention period. Between-group differences in the pre- to post-intervention change in skeletal muscle mass and physical function were evaluated using an analysis of variance. The pre- to post-intervention increase in the skeletal muscle mass index was significantly higher for the three experimental groups （three group: p<0.05）． The pre- to post-intervention increase in the knee extension strength was significantly higher for the exercise and whey protein supplementation group and the exercise group, （exercise and whey protein group and exercise group: p<0.05）． However, We could not observed the increase in skeletal muscle mass index and knee extension strength was significantly greater for the exercise and whey protein supplementation group than for the exercise group. Whey protein supplementation, ingested after resistance exercise, could not be additional effective for the treatment of sarcopenia among elderly.
