The impact of exercise and vitamin D supplementation on physical function in community-dwelling elderly individuals: A randomized trial

We investigated the impact of exercise and vitamin D supplementation on physical function and locomotor dysfunction in community-dwelling elderly individuals. In total, 148 community-dwelling elderly individuals (aged ≥60 years) who were not taking osteoporosis medications participated in a 24-week intervention. The participants were randomly divided into an exercise group, vitamin D group, and exercise and vitamin D group. The participants and outcome-assessing staff were not blinded to group assignment. Exercise comprised three daily sets each of single-leg standing (1 min/leg/set) and squatting (5–6 repetitions/set); vitamin D supplementation was 1000 IU/day. Participants were contacted every 2 weeks to check on their condition and encourage continued participation. The primary outcome was lower limb muscle strength and mass; secondary outcomes were several physical function measurements, serum 25-hydroxyvitamin D levels, and results of a self-assessment questionnaire completed pre- and post-intervention. We analyzed data from 45, 42, and 43 participants in the exercise, vitamin D, and exercise and vitamin D groups, respectively, who completed the intervention. Locomotive syndrome, which involves reduced mobility due to locomotive organ impairment, was diagnosed in 99 participants (76.2%). Many physical function measurements improved in all groups. Lower limb muscle mass increased significantly in all three groups, with no significant differences between the groups in the degree of change. The average serum 25-hydroxyvitamin D of all vitamin D-supplemented participants increased from 28.1 ng/ml to 47.3 ng/ml after vitamin D supplementation. Both exercise and vitamin D supplementation independently improved physical function and increased muscle mass in community-dwelling elderly individuals. Moreover, the combination of exercise and vitamin D supplementation might further enhance these positive effects. UMIN Clinical Trial, UMIN000028229.