We are an ageing population with life expectancy currently increasing at 2 years per decade. Crucially, healthy life expectancy is not keeping pace and older adults are now spending longer in poor health.~Sarcopenia represents a major, serious and increasing public health problem. While the causes of sarcopenia are still unclear, vitamin D deficiency, which is widespread among older adults (reaching 90% in residential care), is associated with an increased risk of falls and fractures as well as skeletal muscle weakness. While it is known that vitamin D is essential for bone health, relatively little is known about the direct effects of vitamin D3 supplementation on human muscle mass and function in humans.~Physical activity (resistance exercise training (RET) in particular) is the most potent stimulus for skeletal muscle hypertrophy in both young and older adults. The researchers and others have shown that even in very old adults (>75 years) and frail patient groups, RET improves muscle strength and functional outcomes although the hypertrophic ability of older muscle is blunted compared with younger adults. Therefore in order to help older adults maintain good musculoskeletal health, interventions to optimise responsiveness to physical activity are likely to be most effective if they are multimodal, and include resistance exercise. One example of this is to combine resistance exercise training with vitamin D supplementation.~The aim of the EXVITD study is to determine whether vitamin D3 supplementation is any more effective in improving musculoskeletal function when combined with exercise training compared with exercise training alone.~The researchers aim to recruit 127 men and women aged 65 years or over who are ambulatory (with or without walking aids) and live in supported housing settings. Recruitment will be via local housing trusts/seniors groups.~Participants will be randomised to RET (x3 per week) + 800 International Units (IU) vitamin D3 (daily) supplement or RET + placebo for six months. Participants will be stratified on the basis of vitamin D status, physical activity (measured directly pre-randomisation using accelerometry), and sex.~Tests will include, but are not limited to, lower limb extensor power (LLEP) output, body composition, Short Physical Performance Battery (SPPB), Timed-up-and-go (TUG),power required to rise from a chair, physical activity, perception of musculoskeletal comfort/pain, falls as events, quality of life and venepuncture for biochemical markers.
This study aims to determine whether vitamin D3 supplementation is any more effective in improving musculoskeletal function when combined with exercise training compared with exercise training alone.