Standing balance after vestibular stimulation in Tai Chi-practicing and nonpracticing healthy older adults

OBJECTIVE: To compare the effects of vestibular stimulation on standing balance control between Tai Chi practitioners and older subjects. DESIGN: Cross-sectional study. SETTING: University-based rehabilitation center. PARTICIPANTS: Tai Chi practitioners (n=24; age +/- standard deviation, 69.3+/-5.0y) and control subjects (n=24; age, 71.6+/-6.1y) were recruited. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subjects stood on a force platform with eyes closed before and after stimulation of their horizontal semicircular canals, applied by means of whole head-and-body rotation at 80 degrees /s for 60 seconds, with subjects seated in a rotational chair. Body sway during stance was measured as total sway path, peak amplitudes, and mean velocities of sway in both anteroposterior (AP) and mediolateral (ML) directions. RESULTS: After head-and-body rotation, significant within-group increases were found in all measures in both AP and ML directions during stance with eyes closed in older control subjects but not in Tai Chi practitioners along the AP direction. In fact, significantly smaller increases in total sway path, peak amplitude, and mean velocity of body sway in the AP direction were found in the Tai Chi practitioners when compared with those of control subjects. CONCLUSIONS: Our results show that long-term Tai Chi practitioners had better AP standing balance control after vestibular stimulation than older control subjects.     

Joint kinetics during Tai Chi gait and normal walking gait in young and elderly Tai Chi Chuan practitioners

BACKGROUND: Tai Chi Chuan is becoming a popular exercise among elders. This study measured the inter-segmental forces and moments at the lower extremity joints during a Tai Chi gait as compared to those during normal walking gait, in both apparently healthy young and elderly Tai Chi Chuan practitioners. METHODS: Three-dimensional inter-segmental joint reaction force and moment were computed using the Inverse Dynamic Approach based on the kinematics and ground reaction force measurements in a laboratory setting in six young (two females, mean age 28; SD 6 years) and six elderly (five females, mean age 72; SD 8 years) subjects who had previous training of Yang style Tai Chi Chuan. FINDINGS: The results showed significant gait differences in both age groups, with significantly smaller peak compressive forces, larger peak shear forces in the ankle, knee and hip joints, and larger peak moments in the knee and hip joints during Tai Chi gait as compared to normal gait. Moreover, the peak shear force was oriented more in the medial-lateral direction at the ankle and knee joints, and the peak moment was in the frontal plane at the knee and hip joints. The results also showed significant age differences, with significantly smaller peak shear forces in all three joints in the elderly group than in the young group during Tai Chi gait. INTERPRETATION: Tai Chi gait has an increased shear force and frontal plane torque at lower extremity joints than normal gait. The shear force at all three lower extremity joints during Tai Chi gait is lower in the elderly subjects than young subjects. This data suggest that, in Tai Chi Chuan training, elderly people with degenerative joint diseases in the lower extremity should use caution when practicing Tai Chi Chuan.     

Mediolateral sway in single-leg stance is the best discriminator of balance performance for Tai-Chi practitioners

OBJECTIVES: To identify a balance measure that can best distinguish Tai-Chi from non-Tai-Chi practitioners and to examine whether longer Tai-Chi practice results in better balance control. DESIGN: Cross-sectional comparative study. SETTING: Community. PARTICIPANTS: Nineteen Tai-Chi practitioners (who practiced Tai Chi for 30-45min at least 3/wk for >1y) and 19 healthy subjects with regular exercise habits (who practiced Tai Chi for 30-45min at least 3/wk for >1y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Scores on 2 clinical tests (functional reach, gait) and 1 laboratory test (postural sway). RESULTS: Tai-Chi practitioners had better clinical test scores for functional reach, gait speed, stride length, and sway parameters during single-leg stance (P<.05). Sway in mediolateral direction during single-leg stance was the balance performance variable that best discriminated the Tai-Chi group from non-Tai-Chi group. More experience practicing Tai Chi was associated with better balance performance. CONCLUSIONS: Tai-Chi practitioners performed better both in clinical and laboratory tests when compared with subjects who did not practice Tai Chi. More Tai-Chi experience was associated with better postural control.     

Effects of Aging and Tai Chi on Finger-Pointing Toward Stationary and Moving Visual Targets

Kwok JC, Hui-Chan CW, Tsang WW. Effects of aging and Tai Chi on finger-pointing toward stationary and moving visual targets.

Objective

To examine the aging effect on speed and accuracy in finger pointing toward stationary and moving visual targets between young and older healthy subjects and whether or not Tai Chi practitioners perform better than healthy older controls in these tasks.

Design

Cross-sectional study.

Setting

University-based rehabilitation center.

Participants

University students (n=30) (aged 24.2±3.1y), were compared with healthy older control subjects (n=30) (aged 72.3±7.2y) and experienced (n=31) (mean years of practice, 7.1±6.5y) Tai Chi practitioners (aged 70.3±5.9y).

Interventions

Not applicable.

Main Outcome Measures

Subjects pointed with the index finger of their dominant hand from a fixed starting position on a desk to a visual signal (1.2cm diameter dot) appearing on a display unit, as quickly and as accurately as possible. Outcome measures included (1) reaction time—the time from the appearance of the dot to the onset of the anterior deltoid electromyographic response; (2) movement time—the time from onset of the electromyographic response to touching of the dot; and (3) accuracy—the absolute deviation of the subject's finger-pointing location from center of the dot.

Results

Young subjects achieved significantly faster reaction and movement times with significantly better accuracy than older control subjects in all finger-pointing tasks. Tai Chi practitioners attained significantly better accuracy than older controls in pointing to stationary visual signals appearing contralaterally and centrally to their pointing hand. They also demonstrated significantly better accuracy when the target was moving. Accuracy in Tai Chi practitioners was similar to young controls.

Conclusions

Eye-hand coordination in finger-pointing declines with age in time and accuracy domains. However, Tai Chi practitioners attained significantly better accuracy than control subjects similar in age, sex, and physical activity level.     

The effects on sensorimotor performance and balance with Tai Chi training

OBJECTIVES: To compare the effects of short-term and long-term Tai Chi training on the sensorimotor and balance performance of able-bodied subjects. DESIGN: A nonrandomized cross-sectional controlled trial. SETTING: Sport laboratory. PARTICIPANTS: Forty-eight healthy subjects, 16 with 3 months of experience in Tai Chi training, 16 with 1 to 3 years of experience in Tai Chi training, and 16 with no experience in Tai Chi training. INTERVENTION: Experimental. MAIN OUTCOME MEASURES: The reflex contraction latencies (reaction time) of medial hamstrings and gastrocnemius after perturbation, the active knee joint angle-repositioning error, and the balance time on a tilt board were measured and analyzed with 1-way analysis of covariance. Significant results were further analyzed with post hoc linear contrasts. RESULTS: Long-term Tai Chi practitioners had a significantly faster reflex reaction time in hamstrings (P<.000) and gastrocnemius (P=.043) muscles and a longer balance time on a tilt board (P<.000) than short-term Tai Chi practitioners and nonpractitioners. Both long- and short-term Tai Chi practitioners had significantly less knee joint angle-repositioning error than nonpractitioners (P=.001 and P=.027, respectively). CONCLUSIONS: Tai Chi training of more than 1 year might have the benefits of faster hamstrings and gastrocnemius reflex reaction and improved knee joint position sense (JPS). These changes might be associated with an improved dynamic standing balance. Better knee JPS was shown in subjects with 3 months of Tai Chi practice, but this had not led to a significant improvement in balance.     

Trunk Position Sense in Older Tai Chi Sword Practitioners

To examine whether older Tai Chi sword practitioners had developed better trunk position sense than healthy control subjects, 16 female Tai Chi sword practitioners from a local community Tai Chi Club in Hong Kong were compared with 11 female healthy control subjects. Active trunk repositioning was used to test trunk proprioceptive acuity. Tai Chi sword practitioners made significantly smaller absolute angle errors than control subjects in trunk rotation to the left (2.2° ± 0.9° vs. 4.4° ± 2.7°; p = 0.006) and to the right (2.1° ± 0.9° vs. 4.2° ± 2.9° of control; p = 0.01), but there were negligible improvements in trunk forward flexion (3.9° ± 3.0° and 4.8° ± 3.0°, respectively; p = 0.46). These results demonstrate that Tai Chi sword practitioners had developed better position sense in trunk rotation but not in trunk flexion than healthy older subjects.     

Speed effect of selected Tai Chi Chuan movement on leg muscle activity in young and old practitioners

Background

Tai Chi Chuan is becoming a popular exercise for improving balance and preventing falls in the elderly. To date, there is no quantitative study investigating the effect of Tai Chi Chuan movement speed on leg muscle function. This study investigated the effect of Tai Chi Chuan exercise performed at different speed on leg muscle activity characteristics in both young and old Tai Chi Chuan practitioners.

Methods

Surface electromyography of six leg muscles and kinematics of lower extremity joints were measured in young and old subjects during Tai Chi Chuan practice at fast, normal, and slow speed, respectively. The magnitude and duration of activation, and durations of isometric, concentric and eccentric actions of each muscle were compared among three speeds and between two groups.

Findings

The activation duration of all six leg muscles was significantly longer at slower speed than at faster speed (P < 0.039). The durations of isometric, concentric and eccentric actions were either longer at the slower speed or did not change with speed for all six leg muscles. The action of knee extensor was primarily isometric at slower speed (P = 0.004), and increased significantly to concentric and eccentric at faster speed (P < 0.031). The activation magnitude of posterior leg muscles increased with speed (P < 0.009). The old subjects had significantly shorter activation duration and lower activation magnitude in several leg muscles than the young, but similar speed effect as the young.

Interpretation

The activation duration and function of leg muscles, especially the knee extensor muscle, are significantly affected by the speed of the selected Tai Chi Chuan movement. Practicing Tai Chi Chuan at different speed may alter the role of muscular function in movement control.     

The effects of practicing sitting Tai Chi on balance control and eye-hand coordination in the older adults: a randomized controlled trial

Abstract

Purpose: The purpose of this study was to examine the effects of 3 months of sitting Tai Chi training on the sitting balance control and eye-hand coordination of older adults subjects. Methods: We randomly assigned 59 older adults from four residential care facilities to either sitting Tai Chi group or mobilizing exercises group as control. The sitting Tai Chi group underwent 3 months of training with a total of 36 sessions (1 hour/session, 3 sessions/week). The outcome measures included sitting balance tests (testing sequential weight shifting and forward reaching in a sitting position) and eye-hand coordination tests (reaction time, movement time and accuracy in finger pointing task). Results: The Tai Chi practitioners showed significant improvement in their sequential weight shifting while sitting (improved by 29.0%, p?≤?0.05) and in their maximum reaching distance from a sitting position (improved by 21.2%, p?≤?0.05). No such improvements were found in the control group. In the eye-hand coordination test, the sitting Tai Chi practitioners had significant improvements in accuracy (improved by 17.3%, p?≤?0.05). Also, no improvement was found in the control group. Conclusions: The results demonstrate 3-months of sitting Tai Chi training can improve sitting balance and accuracy in finger pointing task in the older adults.

• Implications for Rehabilitation

• Traditional Tai Chi poses difficulties for older adults with poor standing balance.

• This pilot study showed that a 3 months sitting Tai Chi training can improve sitting balance and accuracy in the finger pointing task in the older adults.

• Sitting Tai Chi can be a therapy option for older adults with poor standing balance.

     

Effectiveness of a community-based Tai Chi program and implications for public health initiatives

OBJECTIVES: To establish whether the reported beneficial physiologic effects of Tai Chi when performed under stringent experimental conditions can be generalized to the community. DESIGN: Phase 1: pre-post comparison in a group inexperienced in Tai Chi. Phase 2: baseline comparison between inexperienced and experienced Tai Chi groups. SETTING: A community in Hong Kong. PARTICIPANTS: Phase 1: 51 subjects inexperienced in Tai Chi (novice group) participated in the program. Phase 2: baseline measures of the novice group were compared with those of an experienced group (n=49) who had practiced Tai Chi for at least 6 months. INTERVENTION: A Cheng 119 style program was taught by a Tai Chi master for 1.5 hours, 3 times weekly, for 12 weeks. MAIN OUTCOME MEASURES: Lung function and physical activity evaluated before and after the completion of the program. Resting heart rate, blood pressure, oxygen saturation, handgrip strength, flexibility, and balance measured at the program commencement, 6 weeks, and 12 weeks. RESULTS: Phase 1: after the program, the novice group had increased handgrip strength, flexibility, and peak expiratory flow rate. Phase 2: the experienced group had greater flexibility, lower resting heart rate but higher diastolic blood pressure than the novice group prior to training. CONCLUSIONS: A community-based Tai Chi program produces beneficial effects comparable to those reported from experimental laboratory trials of Tai Chi; therefore, it should be considered as a public health strategy.     

Tai chi improves cognitive and physical function in the elderly: a randomized controlled trial

[Purpose] To investigate the effect of Tai Chi on cognitive and physical function in the elderly. [Subjects and Methods] A randomized trial design was used. A total 150 subjects were enrolled and were divided into Tai Chi and control groups. Subjects in the Tai Chi group participated Tai Chi for 6 months, and subjects in the control group participated in other non-athletic activities. [Results] There were no differences between the groups in the one leg standing time with eyes open, left grip strength, or the Frontal Assessment Battery at bedside after 3 and 6 months of intervention. The Mini-Mental State Examination scores after 3 and 6 months were higher in the Tai Chi group than in the control group. The right grip strength after 3 months increased more in the Tai Chi group than in the control group. Both the 5-m high walking speed and 10-m normal walking speed were significantly lower after 3 and 6 months of Tai Chi practice. [Conclusion] These results suggest that regular Tai Chi practice may improve cognitive and physical function in the elderly.Key words: Tai Chi, Mobility, Cognition     

Improvement of isokinetic knee extensor strength and reduction of postural sway in the elderly from long-term Tai Chi exercise

OBJECTIVES: To compare isokinetic strength of leg muscles and foot center of pressure (COP) as a measure of sway between long-term Tai Chi practitioners and controls. DESIGN: Cross-sectional study. SETTING: Community setting. PARTICIPANTS: Twenty subjects in the Tai Chi group and 19 subjects in the control group (age, >55 y). INTERVENTION: Subjects in Tai Chi group had practiced Tai Chi for a minimum of 3 years. MAIN OUTCOME MEASURES: Concentric and eccentric strength of knee extensors and flexors at 60 degrees/s and 120 degrees/s, and foot COP displacement during quiet stance with eyes open or closed. RESULTS: People in the Tai Chi group had significantly higher knee extensor strength at all speeds tested (P<.013), and smaller foot COP excursions for both eyes open and eyes closed conditions (P<.05) than people in control group. No significant difference existed in knee flexors between the 2 groups (P<.713). The COP excursions correlated significantly with the eccentric strength of knee extensors (P<.07) but not with the concentric strength of knee extensors (P<.14) or with the isokinetic strength of knee flexors at most of the speeds (P<.27). CONCLUSION: These findings support the hypothesis that the maintenance of eccentric strength of postural muscles in the lower extremities, which is beneficial for maintaining good postural stability, is helped through the long-term practice of Tai Chi.     

太极拳练习者膝关节疼痛调查研究

目的:了解太极拳练习者膝关节疼痛的发病率。探讨太极拳练习者发生膝关节疼痛的原因和预防膝关节疼痛的方法。方法:采用现场发放问卷的方式对373位太极拳练习者的性别、年龄;练习太极拳时间;准备活动时间;准备活动形式;对拳理了解程度;学习太极拳前是否有膝关节疼痛;练习太极拳过程中是否有膝关节疼痛等问题进行调查。结果:收回有效问卷355份,练习太极拳前有膝关节疼痛131人占36.90%,练习过程中出现膝关节疼痛175人占49.30%。经统计学分析练习中膝关节疼痛发生率由于练习者性别、拳理了解程度、准备活动时间,以及练习太极拳前有无膝关节疼痛的不同而存在显著差异。练习中膝关节疼痛主要出现在屈膝重心下移和屈膝重心下移加转体的动作形式中。结论:太极拳练习会增加膝关节疼痛风险;通过加强拳理学习,适当增加准备活动时间,加强股四头肌力量和膝关节控制能力并积极治疗练习前的膝痛有助于降低练习过程中膝关节疼痛发生率。     

Stance duration under sensory conflict conditions in patients with hemiplegia

Standing balance was evaluated in ten subjects with hemiplegia using a sensory organization balance test (SOT). The SOT is a timed balance test which evaluates somatosensory, visual, and vestibular function for maintenance of upright posture. The duration of bilateral stance was assessed using combinations of three visual and two support surface conditions. Stance time was measured with eyes open, eyes closed, and with each patient wearing a visual dome to produce inaccurate visual information. The support surface conditions involved stance on a hard flat floor followed by attempted stance on a compliant foam surface. Visual deprivation or visual conflict conditions did not cause a loss of balance when stance was performed on a stable surface. However, a lower stance duration was found when patients stood on a compliant surface (p less than .05). Visual compensation was evident during the compliant-surface condition because stance duration showed the greatest reductions with eyes closed and with the visual dome. These findings suggest that the ability to integrate somatosensory information from the lower extremities for balance is compromised after cerebrovascular disease. The implications for diagnosing the specific cause of balance dysfunction and for developing sensory-specific therapeutic interventions are discussed.     

太极拳运动对老年人身体素质的影响

目的:研究长期规律太极拳运动对老年人身体素质的影响.方法:随机抽取81例60～75岁老年人,均排除心血管及糖尿病等严重疾病.对其中常年无锻炼的38例为对照组;练习太极拳＞3年的43例为锻炼组.2组均进行反映灵敏素质、力量素质、平衡素质及柔韧素质的反应时,握力,闭目单足站立时间及坐位体前屈的测试.结果:与对照组比较,锻炼组男、女反应时均显著缩短(P＜0.01,0.05),握力显著增高(P＜0.01),闭目单足站立时间明显延长(P＜0.05),坐位体前屈距离明显增大(P＜0.05).结论:长期坚持太极拳锻炼,可以有效改善老年人整体身体素质,对于延缓身体机能老化有积极意义.     

The beneficial effects of Tai Chi Chuan on blood pressure and lipid profile and anxiety status in a randomized controlled trial

OBJECTIVES: To evaluate the effects on blood pressure, lipid profile, and anxiety status on subjects received a 12-week Tai Chi Chuan exercise program. DESIGN: Randomized controlled study of a Tai Chi Chuan group and a group of sedentary life controls. SETTING: Taipei Medical University Hospitals and University campus in the Taipei, Taiwan, area. SUBJECTS: Two (2) selected groups of 76 healthy subjects with blood pressure at high-normal or stage I hypertension. INTERVENTION: A 12-week Tai Chi Chuan exercise training program was practiced regularly with a frequency of 3 times per week. Each session included 10-minute warm-up, 30-minute Tai Chi exercise, 10-minute cool-down. Exercise intensity was estimated to be approximately 64% of maximal heart rate. OUTCOME MEASURES: Blood pressure, lipid profile and anxiety status (State-Trait Anxiety Inventory; STAI) were evaluated. RESULTS: After 12-weeks of Tai Chi training, the treatment group showed significant decrease in systolic blood pressure of 15.6 mm Hg and diastolic blood pressure 8.8 mm Hg. The serum total cholesterol level decreased 15.2 mg/dL and high-density lipoprotein cholesterol increased 4.7 mg/dL. By using STAI evaluation, both trait anxiety and state anxiety were decreased. CONCLUSIONS: This study shows that under well-designed conditions, Tai Chi exercise training could decrease blood pressure and results in favorable lipid profile changes and improve subjects' anxiety status. Therefore, Tai Chi could be used as an alternative modality in treating patients with mild hypertension, with a promising economic effect.     

Effects of Tai Chi Intervention on Dual-Task Ability in Older Adults: A Pilot Study

Hall CD, Miszko T, Wolf SL. Effects of Tai Chi intervention on dual-task ability in older adults: a pilot study.

Objective

To determine if a 12-week program of Tai Chi that has been shown to reduce falls incidence in older adults would improve the ability to allocate attention to balance under dual-task conditions.

Design

Pre-/posttest experimental research design.

Setting

Movement studies research laboratory.

Participants

Community dwelling older adults (N=15; range, 62-85y) participated in either Tai Chi training or health education classes (controls) for 12 weeks.

Interventions

Participants in the Tai Chi group attended a twice-weekly, 1.5-hour class taught by an experienced instructor. The control group attended a biweekly, 1-hour class for lectures on health-related topics.

Main Outcome Measures

Two cognitive tasks (responding to auditory or visual stimulus as quickly as possible) were performed concurrently while maintaining static balance during the Sensory Organization Test (SOT) and while avoiding obstacles while walking. The percent change in performance relative to the single-task condition was calculated and defined as the dual-task cost. The dual-task cost was calculated for both the postural and cognitive measures.

Results

There was no improvement in the performance of postural stability or cognitive task under dual-task conditions for the SOT for Tai Chi versus controls. There was no improvement in avoiding obstacles under dual-task conditions for Tai Chi versus controls.

Conclusions

Contrary to our hypothesis, the findings of this study did not support a benefit of Tai Chi on the ability to allocate attention to balance under dual-task conditions.     

The duration and plantar pressure distribution during one-leg stance in Tai Chi exercise

BACKGROUND: Tai Chi exercise improved the balance control and muscle strength of the lower extremities. The aim of this study is to quantify the one-leg stance duration and plantar pressure distribution during the one-leg stance in Tai Chi and to try to elaborate on its probable effects on the ability to balance on one leg. METHODS: Sixteen experienced Tai Chi practitioners participated in this study. The Novel Pedar-X insole system was used to record the plantar forces during the execution of a set of 42-form Tai Chi movements and during normal walking. The one-leg stance duration and plantar pressure distribution during the one-leg stance were analyzed. FINDINGS: In Tai Chi exercise, the total duration spent in the one-leg stance was less (p<0.05), the duration of each one-leg stance was longer (p<0.01) and the medial-lateral displacement of the centre of pressure was greater (p<0.05) than during normal walking. The peak pressure and pressure-time integral of the second and third metatarsal heads and the fourth and fifth metatarsal heads were significantly greater (p<0.05) than those of other plantar regions during the one-leg stance in normal walking, whereas the peak pressure and pressure-time integral of the first metatarsal head and the great toe were significantly greater (p<0.05) than those of other plantar regions during the one-leg stance in Tai Chi exercise. INTERPRETATION: The longer duration of each one-leg stance and the plantar pressure distribution characteristics during the one-leg stance in Tai Chi exercise may be associated with an improved ability to balance on one leg. The findings may provide useful information toward the development of strengthening programs, strategies for the prevention of falls, and the promotion of a physically active lifestyle.     

Measurement properties of Tai Chi exercise self-efficacy among ethnic Chinese with coronary heart disease risk factors: a pilot study.

BACKGROUND: Improvement in aerobic capacity and reduction in blood pressure after Tai Chi exercise programs in persons with coronary heart disease (CHD) or with CHD risk factors have been reported. Self-efficacy has been shown to be a consistent predictor of behavioral outcomes, now being applied to Tai Chi exercise. AIM: To assess the utility and appropriateness of existing tools measuring aspects of Tai Chi exercise self-efficacy (TCSE) in a new population, ethnic Chinese with CHD risk factors. Specific objectives were: (1) examine acceptability and feasibility; (2) determine score distributions; (3) assess the reliability and known-groups validity; (4) translate tool into an equivalent Chinese version and determine if there were any differences between ethnic Chinese and non-Chinese. METHODS: Following a review of the literature, two existing tools used with Caucasians were found and modified; a 9-item exercise self-efficacy tool developed by Resnick and Jenkins [Resnick B, Jenkins LS, Testing the reliability and validity of the Self-Efficacy for Exercise scale. Nurs. Res. 49(3) (2000) 154-159], and a 3-item tool developed by Li et al. [Li F, McAuley E, Harmer P, Duncan TE, Chaumeton NR, Tai Chi enhances self-efficacy and exercise behavior in older adults. J. Aging Phys. Act. 9 (2001) 161-171] to assess gradations of the challenge to perform Tai Chi among elderly populations. The modified TCSE tool was translated into Chinese and back-translated. A pilot study was conducted to pre-test the modified 14-item TCSE tool in ethnic Chinese and non-Chinese. RESULTS: A total of 18 subjects (mean age = 60 years, S.D. = 18.4) participated. Seven subjects (39%) identified themselves as ethnic Chinese. Ten subjects (56%) had experience performing Tai Chi, ranging from 3 months to 17 years (mean = 5.0 years, S.D.=5.0). Half of the subjects reported having a history of hypertension (n = 9, 50%), while nearly one-third reported having high cholesterol (n = 5, 28%). No significant difference in TCSE mean scores was found between ethnic Chinese and non-Chinese (p > 0.05). Internal consistency estimates were very high (TCSE Barriers, r = 0.95; TCSE Performance, r = 0.97). A statistically significant difference was found in the TCSE mean scores between Tai Chi practitioners and non-practitioners (TCSE Barriers, t = -3.3, p = 0.01; TCSE Performance, t = -2.7, p = 0.03), with Tai Chi practitioners reporting higher self-efficacy; thus providing initial evidence of known-groups validity. CONCLUSIONS: Measurement of self-efficacy to overcome barriers to Tai Chi exercise (TCSE Barriers) and self-efficacy to perform Tai Chi (TCSE Performance) functioned well in this sample. The acceptability and feasibility of this tool was established and known-groups validity was confirmed. Further research using this tool among ethnic Chinese with CHD or CHD risk factors, including those with less than high school education or low literacy, is recommended as the next step in development of TCSE.     

The Effects of a Complex Exercise Program with the Visual Block on the Walking and Balance Abilities of Elderly People

[Purpose] The purpose of this study was to investigate the effect of a complex exercise program for elderly people who had experienced a fall on their balance, gait, vestibular senses, and proprioceptive senses when their visual sense was blocked. [Subjects and Methods] The subjects were 30 healthy elderly people aged 65 or older. They were equally and randomly divided into a visual block (VB) group (those whose eyes were covered) and a visual permission (VP) group. The subjects performed the complex exercise program for 30 minutes, twice a day, five day a week for 4 weeks a total of 20 times. Outcome measures were the10 meter walking test (10MWT), stair up/down test (SUDT), Berg balance scale (BBS), vestibular stepping test (VST), proprioception test (PT). [Results] After the intervention, the VB group showed improvements in 10MWT, VST, and PT. The VP group showed improvements in 10MWT and PT. The significant improvement in VST observed in the VB group was significantly greater than that in the VP group. [Conclusion] The complex exercise program for elderly people helped enhance their balance ability and gait, and improved their vestibular sense.Key words: Complex exercise, Elderly, Visual block