Regular Tai Chi Chuan exercise may retard bone loss in postmenopausal women: A case-control study

Objective: To evaluate the potential benefits of regular Tai Chi Chuan exercise on the weight-bearing bones of postmenopausal women. Design: Case-control study. Setting: University medical school in Hong Kong. Participants: Postmenopausal women (age range, 50-59y), including 17 self-selected regular Tai Chi Chuan exercisers (TCE) with over 4 years of regular exercise, and 17 age- and gender-matched nonexercising controls (CON). Interventions: Not applicable. Main Outcome Measures: Bone mineral density (BMD) in the lumbar spine and proximal femur was measured at baseline and at follow-up 12 months later by using dual-energy x-ray absorptiometry (DXA) and in the distal tibia using multislice peripheral quantitative computed tomography (pQCT). Results: Baseline results showed that the TCE group had significantly higher BMD (10.1%-14.8%, all P<.05) than the CON group in the lumbar spine, proximal femur, and the ultradistal tibia. The follow-up measurements showed generalized bone loss in both groups. Although both DXA and pQCT measurements revealed decelerated rates of bone loss in the TCE group, only the more sensitive pQCT showed significantly reduced rate of bone loss in trabecular BMD of the ultradistal tibia (TCE vs CON: -1.10%+/-1.26% vs -2.18%+/-1.60%, P<.05) and of cortical BMD of the distal tibial diaphysis (TCE vs CON: -0.90%+/-1.36% vs -1.86%+/-0.93%, P<.05). Conclusion: This is the first case-control study to show that regular Tai Chi Chuan exercise may help retard bone loss in the weight-bearing bones of postmenopausal women.