Physical activity and biochemical markers of bone turnover in elderly patients

To assess the role of physical therapy in improving the remodelling processes of bone turnover, biochemical markers of bone formation and resorption (osteocalcin, parathormone, bone-specific alcaline phosphatase, somatotropic hormone, C-terminal propeptide type I procollagen, somatomedin, insulin-like growth factor bound protein, C-terminal telopeptide type I collagen) have been investigated in elderly patients before and after a cycle of physical therapy. Patients of both sexes, immobilized on hospital admission day because of fractures or neurologic diseases, underwent physiotherapy for one month. Following physical treatment we found significant increases of osteocalcin, bone-specific alcaline phosphatase and somatomedin in the female group, while no significant difference was detected in males. Our data support that the mechanical stimulus significantly improves the recovery of osteoblastic activity in women, while in men the increases in bone remodelling markers are not significant. Differences in life-style between male and female patients are proposed as determinants in the bone remodelling response to physical therapy.