Response of calciotropic hormones and bone turnover to brisk walking according to age and fitness level.

Ageing is associated with a gradual bone loss and physical activity has been suggested as practical strategy for a non-pharmacological prevention of osteoporosis. However, until now, the specific mechanism by which physical activity affects bone tissue is not thoroughly understood. The aim of this study was to evaluate the effect of strenuous exercise on bone metabolism as a function of age and fitness level.

Effect of antioxidants and exercise on bone metabolism.

We examined the effects of antioxidant supplementation in association with progressive aerobic training on the bone metabolism of healthy elderly individuals. For 8 weeks, 13 participants (mean age 74 years) received vitamin C (500 mg) and vitamin E (100 mg) daily and participated in a supervised progressive aerobic training programme. After the 8 weeks, 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations were increased significantly by 42.

No negative impact of reduced leptin secretion on bone metabolism in male decathletes.

This study investigated the effect of intense physical activities that generate high mechanical constraints on bone metabolism and serum leptin concentrations and the potential relationships among bone mineral density (BMD), bone biochemical markers and leptin variation. Thirteen male decathletes (mean age 22.4 +/- 2.

The role of androgens or growth factors in the bone resorption process in recent spinal cord injured patients: a cross-sectional study.

Study Design: This cross-sectional study compared the androgen and growth factor profiles and the bone turnover of patients with spinal cord injury (SCI) versus able-bodied controls (AB).

Objective: Determine whether androgens, GH, or either IGF-I or IGFBP-3, are implicated in bone turnover alteration in patients with recent SCI.

Setting: Propara Center, Montpellier, France.

The intensity level of physical exercise and the bone metabolism response.

This study investigated the short-term effects of the intensity level of physical exercise on bone metabolism and related hormones. The responses of calciotropic hormones and bone biochemical markers were evaluated in seven male cyclists (mean age 24.4 years, range 20-39) during two 50-min cycling tests performed 15% below (-VT) and 15% above (+VT) the ventilatory threshold.