Does Lifetime Physical Activity Contribute to Bone Health?

Background: Most past studies on the relationship between physical activity (PA) and bone health consist of exercise training as interventions in randomized controlled trials, while little research has been performed on the cumulative effects of daily life activity and bone mass in large scale studies. Methods: We investigated the relationship between daily life physical activity and bone mass measurements by pooling 4-year public data from a national survey. PA measurements were collected from the physical activity questionnaires, and femoral and spinal bone mass density (BMD) and bone mineral content (BMC) were obtained from the Femoral and spinal Dual Energy X-ray Absorptiometry examination data.  ANOVA and ANCOVA models were fitted to assess the difference in bone measurement across different PA levels. Analysis was stratified by gender and age, adjusting for possible confounding factors. Results: Data were collected from 11,766 subjects. The results showed that different domains of PA affect bone health differently. Amongst all, vigorous PA at leisure time indicated a significant positive association with bone health. This finding was consistent at most bone sites, and was observed more often in male less than 50 years old. Increasing trend in BMD and BMC was also seen in other forms of PA. Conclusion: high level of leisure time PA raised the values of bone measurements.