The effect of exercise and soy protein intake on physical frailty score improvement in community-dwelling elderly: a randomized controlled trial

OBJECTIVE: This study examined the effects of combined exercise and nutrition interventions on physical frailty in community-dwelling older adults. MATERIALS AND METHODS: A randomized controlled trial was conducted with 84 participants (68 women; mean age of 75.5 ± 6.3 years). Participants were assigned to either an exercise-only group or a combined exercise and nutrition group. The 3-month intervention included weekly 1-h exercise sessions (10 sessions total). Outcomes assessed were walking speed, limb skeletal muscle mass index, trunk muscle mass, grip strength, weight loss, fatigue, exercise habits, general cognitive function (Montreal Cognitive Assessment Japanese version, MoCA-J), and biochemical blood test data. RESULTS: Among the 84 participants, 77 (39 exercise-only, 38 exercise + nutrition group) were analyzed. Pre-post comparisons showed a main effect of physical frailty for both groups: 0.82 ± 0.79 pre-post and 0.51 ± 0.68 pre-intervention vs. post-intervention for the exercise group, and 0.82 ± 0.69 pre-post and 0.50 ± 0.60 post-post for the exercise+nutrition group. Walking speed was 1.27 ± 0.21 m/s pre and 1.29 ± 0.21 m/s post in the exercise group and 1.18 ± 0.19 m/s pre and 1.27 ± 0.19 m/s post in the exercise + nutrition group, showing a main effect and interaction effect. Other measures showed significant effects on limb skeletal muscle mass, trunk muscle mass, grip strength, and trunk muscle mass in both groups. CONCLUSIONS: Exercise intervention, with or without nutritional supplementation, significantly reduced physical frailty in older adults. Combining exercise with soy protein intake may improve short-term motor function and physical frailty.