The effects of whole-body vibration training and vitamin D supplementation on muscle strength, muscle mass, and bone density in institutionalized elderly women: a 6-month randomized, controlled trial

Sarcopenia and osteoporosis represent a growing public health problem. We studied the potential benefit of whole-body vibration (WBV) training given a conventional or a high dose of daily vitamin D supplementation in improving strength, muscle mass, and bone density in postmenopausal women. In a 2 × 2 factorial-design trial, 113 institutionalized elderly females aged over 70 years (mean age 79.6 years) were randomly assigned either to a WBV or a no-training group, receiving either a conventional dose (880 IU/day) or a high dose (1600 IU/day) of vitamin D(3). The primary aim was to determine the effects of 6 months of WBV and/or vitamin D supplementation on isometric and dynamic strength, leg muscle mass, and hip bone mineral density (BMD). Additionally, the increase in 25-hydroxyvitamin D [25(OH)D] levels between conventional and high-dose supplementation was compared. After 6 months of treatment, dynamic muscle strength, hip BMD, and vitamin D serum levels improved significantly in all groups, whereas isometric strength and muscle mass did not change. When compared with no training, the WBV program did not result in additional improvements. When compared with 880 IU, a high dose of 1600 IU of vitamin D did result in higher serum vitamin D levels but did not result in additional improvements. In institutionalized women older than 70 years, the WBV training protocol tested is not more efficient in enhancing muscle mass, strength, and hip BMD compared with vitamin D supplementation. A higher dose of 1600 IU of vitamin D does not provide additional musculoskeletal benefit in this population compared with conventional doses.