Objective:
To evaluate three Tai Chi (TC) exercise programs as intervention measures to compare their effects on improving rate of change in bone mineral density (BMD) in elderly individuals with osteoporosis (OP) and to propose the optimal exercise duration.

Methods:
A randomized controlled trial (RCT) was conducted to identify study participants based on inclusion and exclusion criteria. Due to subject attrition, the number of participants analyzed decreased from 60 to 49. These participants were divided into four groups: 24-style TC Chuan group (24TCCG) (n = 13, 7 males/6 females), TC Kung Fu Fan group (TCKFFG) (n = 12, 5 males/7 females), TC Softball group (TCSBG) (n = 11, 6 males/5 females), and a control group (CG) (n = 13, 6 males/7 females). Except for the control group, each group received different TC exercise programs four times a week for 60 min per session, lasting for 16 weeks. BMD was measured using dual-energy X-ray absorptiometry (DXA) at the L2-L4 lumbar vertebrae, Ward's triangle, femoral neck, and greater trochanter. The rate of change of BMD was calculated using the formula.

Results:
Compared with CG, all three TC groups showed significant improvements in BMD changes (P < 0.05), but their effects on the improvement of femoral neck and greater tuberosity BMD change rates were similar (P > 0.05). In addition, compared to the other exercise regimens, 24TCCG demonstrated more significant improvements in BMD at the L2-L4 lumbar vertebrae region and exhibited a more pronounced improvement in Ward's triangle BMD after only 8 weeks (P < 0.05). Short-term (≤ 4 weeks) TCKFFG was more effective than TCSBG in enhancing femoral neck BMD (P < 0.05). However, statistical significance was not found (P > 0.05) in all other cases.

Conclusion:
These three TC exercise programs have similar positive effects on the BMD of the femoral neck and greater trochanter. However, compared with other exercise schemes, 24TCC showed a more significant improvement in BMD of the L2-L4 lumbar vertebrae region after just 8 weeks, as well as a more pronounced improvement in BMD of Ward's triangle. In terms of improving femoral neck BMD, TCKFF was found to be more effective than TCSB in less than 4 weeks. This study provides evidence for the effectiveness of TC exercise in improving BMD and preventing OP in the middle-aged and elderly high-risk population.

Keywords: 24-Style TC Chuan; Bone mineral density; Middle-aged and elderly; Osteoporosis; TC Kung Fu Fan; TC Softball; Tai Chi.

PMID: 38072989 DOI: 10.1186/s13018-023-04324-0

Effect of different types of Tai Chi exercise programs on the rate of change in bone mineral density in middle-aged adults at risk of osteoporosis: a randomized controlled trial