In this year-long study of 117 older adults (≥60 y) were studies in four treatment arms: 1) 3 g HMB plus 2,000 IU Vitamin D per day with exercise; 2) 3 g HMB plus 2,000 IU Vitamin D per day with no exercise; 3) Placebo with exercise; and 4) Placebo with no exercise. All participants had baseline Vitamin D levels from 15-30 ng/mL, which would be considered insufficient for optimal physical functioning. HMB plus Vitamin D supplementation significantly increased lean mass within the non-exercising group at 6 months. Additionally, in the non-exercising groups knee extension peak torque (60⁰/s) was significantly improved at 3 months in the HMB plus Vitamin D group compared with the non-exercising placebo group. A functional index of the physical tests, which included handgrip strength, get up, and get up and go measurements, showed that HMB plus Vitamin D resulted in a significant increase in the functional index at 3, 6, and 12 months of the study. The authors concluded that HMB plus Vitamin D could enhance muscle strength and physical function in older adults even without engaging in an exercise program.