Men's Osteoporosis Support Group
Exercise, calcium and vitamin D effect on BMD
J Clin Endocrinol Metab. 2011 Jan 5. [Epub ahead of print]. Independent and Combined Effects of Calcium-Vitamin D3 and Exercise on Bone Structure and Strength in Older Men: An 18-Month Factorial Design Randomized Controlled Trial. Kukuljan S and others. PMID: 21209030. This was an 18 month, randomized, controlled trial involving 180 Australian men aged 50-79 to determine if calcium- and vitamin D-fortified milk would add any benefit to an exercise program. The exercise involved progressive resistance training with weight-bearing impact activities done 3 days/week. The milk supplement included 1000 mg/day calcium and 800 IU/day of vitamin D3. The results showed no effect on any skeletal site for the fortified milk. However, the exercise gave gains in the femoral neck section modulus and in the areal BMD and cross-sectional area. Exercise also improved the lumbar spine trabecular BMD. The authors concluded, “A community-based multi-component exercise program successfully improved LS and femoral neck BMD and strength in healthy older men, but providing additional calcium-vitamin D3 to these replete men did not enhance the osteogenic response.”
Editor's comments. This recent Update showed weight-bearing exercise that involved wearing a weighted vest or jumping to a height that increased body weight about 2.5 times was effective to either maintain or increase hip bone mineral density (BMD), particularly if done seven days per week. The Kukuljan and others study got increased BMD with a 3 day per week program. But it was progressive, which might be significant. When they say progressive, I assume that means both progressive with additional weight and additional time/repetitions over time.
Interesting is that there was no effect from added calcium or vitamin D. However, these men were replete—they had normal calcium and vitamin D levels when in the program. Thus you wouldn't expect any effect from adding more calcium and/or vitamin D. Only if there is a shortage of one or both nutrients would you expect improvements in BMD by supplementing with them.
Bottom line: do weight-bearing exercise as many times per week as you can—ideally all seven days. If you can make it progressive, that would be better.