Improvement of memory function via a combination of exercise and soy peptide supplementation in community-dwelling older adults: A randomized controlled trial

BACKGROUND: Soy peptide, when consumed as a functional food, has been reported to improve cognitive function. This study aimed to verify the combined effect of soy peptide supplementation and exercise on cognitive function among community-dwelling older adults in Japan. METHODS: In this population-based, non-blinded randomized controlled trial, 72 community-dwelling older adults who were independent in activities of daily living were randomly assigned to an “exercise plus nutrition” program (Ex + Nt group, n = 36) or an exercise program (Ex group, n = 36). For 3 months, both groups participated in an exercise and cognitive training regimen once per week, with the Ex + Nt group receiving soy supplementation once per week. Pre- and post-intervention measurements included grip strength, gait speed, skeletal muscle mass index, and scores on Addenbrooke's Cognitive Examination-Revised, trail-making test A, and the Geriatric Depression Scale. Participant enrollment for this study started in January 2019 and ended in April 2019. RESULTS: Exercise training increased the skeletal muscle mass index by 2.0% and 3.0% in the Ex + Nt and Ex groups, respectively. The Ex + Nt group exhibited a significant 0.3-point increase in the memory score. CONCLUSION: A 3-month exercise program combined with soy peptide supplementation may be effective in improving both motor and memory function in community-dwelling older adults.