Randomized Controlled Trial on the Effects of Resistance Training with or without Nutritional Supplementation of Soy Peptide for the Frail Elderly

Abstract

A randomized controlled trial wa carried out to examine whether supplementation with soya peptide enhance the effects of resistance training for community-dwelling frail elderly in Japan. Subjects included 33 elderly persons who had reported one or more fall experiences in the previous year (designated as "fallers") and 50 elderly persons who had 2 or more geriatric syndromes among fall experience, urinary incontinence, disability in one or more items of 5 instrumental activities of daily living and a low frequency of going outdoors. Subjects within each subgroup were randomly allocated into an exercise group and exercise plus nutritional supplementation group. Both groups participated in a 1-hour supervised resistance training class twice a week for 12 weeks. The nutritional supplementation group was given a soya peptide beverage equivalent to an intake of 32 g of soya protein per week during this period. After the 12-week intervention period, the exercise plus nutritional supplementation group within the "fallers" showed a greater improvement in knee extension power and usual walking speed and greater reduction in white blood cell count than the exercise group. However, no significant additive effect of supplementation was apparent in the multiple geriatric syndrome subgroup. It is concluded that soya peptide may enhance the effect of resistance training in a certain subset of frail elderly.