An Evaluation of Select Physical Activity Exercise Classes on Bone Metabolism

Area of Science:

• Exercise Physiology
• Bone Metabolism
• Sports Science

Background:

• Weight-bearing activities are known to optimize bone mass and prevent osteoporosis.
• The effects of non-weight-bearing activities on bone metabolism are less understood.
• Structured physical activity may offer benefits for bone health.

Purpose of the Study:

• To evaluate the efficacy of structured physical activity classes on bone metabolism.
• To assess the impact of yoga and cardio-kickboxing on bone turnover markers.
• To investigate changes in bone mineral density (BMD) following a 12-week intervention.

Main Methods:

• Twenty-eight premenopausal women (ages 18-35) participated in either a yoga or cardio-kickboxing class twice weekly for 12 weeks.
• Bone mineral density (BMD) of the spine, hip, and total body was measured using dual-energy X-ray absorptiometry (DXA) pre- and post-intervention.
• Serum osteocalcin (OC) levels, a marker of bone formation, were measured via ELISA pre- and post-intervention.

Main Results:

• BMD levels remained stable and did not significantly increase in either group over the 12-week intervention period.
• Both yoga and cardio-kickboxing classes led to a significant increase in serum osteocalcin (OC) levels (68% and 67%, respectively, P < 0.001).
• Baseline characteristics were similar between the yoga and cardio-kickboxing groups.

Conclusions:

• Twelve weeks of yoga and cardio-kickboxing were insufficient to induce measurable changes in bone mineral density (BMD).
• The significant increase in osteocalcin (OC) suggests that these non-weight-bearing activities initiated the bone formation process.
• These findings indicate that structured physical activity, even without weight-bearing, may provide a stimulus for future bone growth, provided exercise is maintained.