Li F, Harmer P, Fisher KJ, McAuley E, Chaumeton N, Eckstrom E, Wilson NL.

Oregon Research Institute, 1715 Franklin Boulevard, Eugene, OR 97403, USA.This email address is being protected from spambots. You need JavaScript enabled to view it.

BACKGROUND: The authors' objective was to evaluate the efficacy of a 6-month Tai Chi intervention for decreasing the number of falls and the risk for falling in older persons. METHODS: This randomized controlled trial involved a sample of 256 physically inactive, community-dwelling adults aged 70 to 92 (mean age, 77.48 years; standard deviation, 4.95 years) who were recruited through a patient database in Portland, Oregon. Participants were randomized to participate in a three-times-per-week Tai Chi group or to a stretching control group for 6 months. The primary outcome measure was the number of falls; the secondary outcome measures included functional balance (Berg Balance Scale, Dynamic Gait Index, Functional Reach, and single-leg standing), physical performance (50-foot speed walk, Up&Go), and fear of falling, assessed at baseline, 3 months, 6 months (intervention termination), and at a 6-month postintervention follow-up. RESULTS: At the end of the 6-month intervention, significantly fewer falls (n=38 vs 73; p=.007), lower proportions of fallers (28% vs 46%; p=.01), and fewer injurious falls (7% vs 18%; p=.03) were observed in the Tai Chi group compared with the stretching control group. After adjusting for baseline covariates, the risk for multiple falls in the Tai Chi group was 55% lower than that of the stretching control group (risk ratio,.45; 95% confidence interval, 0.30 to 0.70). Compared with the stretching control participants, the Tai Chi participants showed significant improvements (p<.001) in all measures of functional balance, physical performance, and reduced fear of falling. Intervention gains in these measures were maintained at a 6-month postintervention follow-up in the Tai Chi group. CONCLUSIONS: A three-times-per-week, 6-month Tai Chi program is effective in decreasing the number of falls, the risk for falling, and the fear of falling, and it improves functional balance and physical performance in physically inactive persons aged 70 years or older.

PMID: 15814861 [PubMed - indexed for MEDLINE]

Tsang WW, Hui-Chan CW.

Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong (SAR), China.

PURPOSE: Our previous studies showed that experienced Tai Chi practitioners had better joint proprioception and balance control during weight shifting. The objective of the present study was to examine whether experienced golfers had attained similar improvement when compared with the Tai Chi practitioners, as well as healthy elderly subjects and young university students. METHODS: We compared 12 experienced elderly Tai Chi practitioners, with 11 experienced elderly golfers, 12 healthy elderly subjects, and 12 young university students, who were all males, using: 1) passive knee joint repositioning test to assess their joint proprioceptive acuity and 2) limits of stability test to assess their ability to voluntarily weight shift within their base of support. RESULTS: Both Tai Chi practitioners and golfers had better knee joint proprioceptive acuity than did the elderly control subjects (P < 0.05). Of special interest is that their performance was similar to that of the young subjects. In the limits of stability test, Tai Chi practitioners and golfers had faster reaction time, leaned further without losing stability, and showed better control of leaning trajectory than did elderly control subjects (all P < 0.05). The latter two outcome measures were also comparable to those of the young subjects. CONCLUSION: These results demonstrate that both experienced Tai Chi practitioners and golfers had improved knee joint proprioception and limits of stability, when compared with those of elderly control subjects similar in age, gender (male), and physical activity level. Such improved outcome measures were comparable to those of young male subjects. These findings suggest that experienced Tai Chi practitioners and golfers had improved joint proprioceptive acuity and dynamic standing balance control, despite the known aging effects in these specific sensorimotor functions.

PMID: 15064594 [PubMed - indexed for MEDLINE]

Tsang WW, Hui-Chan CW.

Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (SAR), China.

PURPOSE: The objectives of this cross-sectional study were to examine whether older Tai Chi practitioners had better knee muscle strength, less body sway in perturbed single-leg stance, and greater balance confidence than healthy older adults. METHODS: Tai Chi and control subjects (N = 24 each, aged 69.3 +/- 5.0 and 71.6 +/- 6.1 yr, respectively) were matched with respect to age, gender, height, weight, and physical activity level. Concentric and eccentric isokinetic tests of the subjects" dominant knee extensors and flexors were conducted at an angular velocity of 30 degrees.s(-1). Control of body sway was assessed in static double-leg stance and in single-leg stance perturbed by forward or backward platform perturbations. The Activities-specific Balance Confidence (ABC) scale was used to investigate subjects" balance confidence in daily activities. RESULTS: Tai Chi practitioners had higher peak torque-to-body weight ratios in concentric and eccentric isokinetic contractions of their knee extensors and flexors (P = 0.044). They manifested less anteroposterior body sway angles in perturbed single-leg but not static double-leg stance than did control subjects (P < 0.001). Tai Chi practitioners also reported significantly higher balance confidence score ratios (P = 0.001). Older adults" knee muscle strengths showed negative correlations with body sway angles in perturbed single-leg stance and positive correlations with ABC score ratios. Moreover, their body sway angles in perturbed single-leg stance were negatively correlated with their ABC score ratios (all P < 0.05). CONCLUSION: Our results demonstrate that long-term Tai Chi practitioners had better knee muscle strength, less body sway in perturbed single-leg stance, and greater balance confidence. Significant correlations among these three measures uncover the importance of knee muscle strength and balance control during perturbed single-leg stance in older adults" balance confidence in their daily activities.

PMID: 15692325 [PubMed - indexed for MEDLINE]