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Effects of a multi-component exercise program and calcium-vitamin-D3-fortified milk on bone mineral density in older
S Kukuljan1, C A Nowson, S L Bass
1Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
Summary:
We examined the independent and combined effects of a multi-component exercise program and calcium-vitamin-D(3)-fortified milk on bone mineral density (BMD) in older men. Exercise resulted in a 1.8% net gain in femoral neck BMD, but additional calcium-vitamin D(3) did not enhance the response in this group of older well-nourished men.
Introduction:
This 12-month randomised controlled trial assessed whether calcium-vitamin-D(3)-fortified milk could enhance the effects of a multi-component exercise program on BMD in older men.
Methods:
Men (n = 180) aged 50-79 years were randomised into: (1) exercise + fortified milk; (2) exercise; (3) fortified milk; or (4) controls. Exercise consisted of high intensity progressive resistance training with weight-bearing impact exercise. Men assigned to fortified milk consumed 400 mL/day of low fat milk providing an additional 1,000 mg/day calcium and 800 IU/day vitamin D(3). Femoral neck (FN), total hip, lumbar spine and trochanter BMD and body composition (DXA), muscle strength 25-hydroxyvitamin D and parathyroid hormone (PTH) were assessed.
Results:
There were no exercise-by-fortified milk interactions at any skeletal site. Exercise resulted in a 1.8% net gain in FN BMD relative to no-exercise (p < 0.001); lean mass (0.6 kg, p < 0.05) and muscle strength (20-52%, p < 0.001) also increased in response to exercise. For lumbar spine BMD, there was a net 1.4-1.5% increase in all treatment groups relative to controls (all p < 0.01). There were no main effects of fortified milk at any skeletal site.
Conclusion:
A multi-component community-based exercise program was effective for increasing FN BMD in older men, but additional calcium-vitamin D(3) did not enhance the osteogenic response.
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