title: Beneficial effects of regular Tai Chi exercise on musculoskeletal system.
abstract: This study was performed to evaluate the potential benefits of regular Tai Chi Chun (TCC) exercise on bone mineral density (BMD) and neuromuscular function in postmenopausal women. In this cross-sectional study, 99 healthy postmenopausal women, with a mean age of 55.9+/-3.1 years and within 10 years after the menopause, were recruited; including 48 subjects who had been regularly practicing TCC exercise for more than 3 h/week and 51 age- and sex-matched sedentary controls (CON). BMD was measured in the lumbar spine and proximal femur of the non-dominant leg (femoral neck, greater trochanter, and Ward's triangle), using dual-energy X-ray absorptiometry (DXA). Neuromuscular function was evaluated, including magnitude of trunk bend-and-reach, quadriceps muscle strength, and single-stance time on the nondominant leg. The TCC group showed overall higher BMD at all measurement sites, with a significant difference found at the spine (7.1%), greater trochanter (7.2%), and Ward's triangle (7.1%) of the proximal femur (all; P<0.05). Functional tests revealed an average 43.3% significantly greater quadriceps strength (P<0.01), and 67.8% significantly longer single-stance time in the TCC group as compared with the CON group (P<0.05), as well as a greater magnitude of trunk bend-and-reach in the TCC group (P=0.08). Bivariate linear correlation analysis showed that quadriceps muscle strength was significantly correlated with the single-stance time (r=0.41; P<0.01). This study revealed that regular TCC exercise may have an association with higher BMD and better neuromuscular function in early postmenopausal women.
authors.affiliation: Department of Orthopaedics and Traumatology, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong. lingqin@cuhk.edu.hk
authors.forename: Ling
authors.initials: L
authors.lastname: Qin
authors.forename: Wingyee
authors.initials: W
authors.lastname: Choy
authors.forename: Kwoksui
authors.initials: K
authors.lastname: Leung
authors.forename: Ping Chung
authors.initials: PC
authors.lastname: Leung
authors.forename: Szeki
authors.initials: S
authors.lastname: Au
authors.forename: Wingyin
authors.initials: W
authors.lastname: Hung
authors.forename: Maximilian
authors.initials: M
authors.lastname: Dambacher
authors.forename: Kaiming
authors.initials: K
authors.lastname: Chan
mesh_terms: D000368:Aged; D015519:Bone Density; D003430:Cross-Sectional Studies; D005260:Female; D006723:Hong Kong; D006801:Humans; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D009142:Musculoskeletal Physiological Phenomena; D017698:Postmenopause / Q000502:physiology; D004856:Postural Balance / Q000502:physiology; D026302:Tai Ji