A combined health promotion program of exercise with protein and vitamin D-enriched menu enhances skeletal muscle mass and strength in Japanese elderly men.

The study aimed to investigate the effectiveness of combining a protein and vitamin D-enriched menu with an exercise program to reduce frailty risk and enhance muscle performance. However, current evidence lacks accurate dosage and effectiveness information for this combination. This study involved Japanese men in their 60s who were randomly assigned to two groups : the ExN group, which received a 10-day exercise program along with enriched diet, and the Ex group, which underwent the exercise program alone. The effects of these interventions on muscle mass, strength, and serum vitamin D metabolite levels were assessed. The ExN intervention resulted in a significant increase in skeletal muscle mass and serum 25-hydroxyvitamin D3 (25(OH)D3) levels, while the Ex intervention did not yield the same effects. These results indicate that a combined program of exercise with protein and vitamin D-enriched meal improves serum 25(OH)D3 levels and skeletal muscle mass among older Japanese men. J. Med. Invest. 72 : 76-84, February, 2025.