Effectiveness of a Community-Based Tai Chi Program and Implications for Public Health Initiatives

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1 619 Effectiveness of a Community-Based Tai Chi Program and Implications for Public Health Initiatives Alice Y. Jones, PhD, PT, Elizabeth Dean, PhD, PT, Rhonda J. Scudds, PhD, PT ABSTRACT. Jones AY, Dean E, Scudds RJ. Effectiveness of a community-based Tai Chi program and implications for public health initiatives. Arch Phys Med Rehabil 2005;86: 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. Key Words: Community networks; Public health; Rehabilitation; Tai Chi; Treatment outcome by American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation From the Department of Rehabilitation Sciences, Hong Kong Polytechnic University, Hong Kong (Jones, Scudds); and School of Rehabilitation Sciences, University of British Columbia, Vancouver, BC, Canada (Dean). Dean was affiliated with the Hong Kong Polytechnic University at the time of this study. Supported by an Area of Strategic Development grant awarded by The Hong Kong Polytechnic University. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the author(s) or on any organization with which the author(s) is/are associated. Reprint requests to Elizabeth Dean, PhD, PT, Sch of Rehabilitation Sciences, University of British Columbia, T Wesbrook Mall, Vancouver, BC V6T 2B5, Canada, elizdean@interchange.ubc.ca /05/ $30.00/0 doi: /j.apmr ACCORDING TO THE World Health Organization 1 and the Ministry of Health in Hong Kong, 2 the leading causes of death in Asian countries are increasingly mimicking those of Western industrialized countries. People from Asia are increasingly susceptible to heart disease, smoking-related diseases, hypertension and stroke, obesity, diabetes, and all forms of cancer. 1 Thus, there is a need to provide public awareness and education campaigns, as well as to promote healthy lifestyles that include regular exercise in Asia as well as in North America in a low-tech, cost-effective manner. Tai Chi is an ancient Chinese practice of disciplined exercise that is publicly practiced by older people in and around the parks and open spaces of Hong Kong, as well as in mainland China and other Asian countries. The practice is characterized by sequential shifting between double-leg and single-leg stance coupled with reciprocal arm movements and coordinated breathing, and spinal rotation (fig 1). When performed for 20 to 60 minutes several times a week for several weeks, Tai Chi provides multisystemic health benefits In addition, Li et al 12 have reported that the functional status of elderly participants (mean age, 72.8y; range, 65 96y) was increased when Tai Chi was practiced for an hour twice a week for 6 months. These findings support the time-honored beliefs about the health benefits of Tai Chi, and lend credence to the contemporary view of it as a unique Chinese therapeutic intervention. Tai Chi appears to hold promise as a health-promoting initiative. Although studies of population- and communitybased programs have become increasingly prevalent, particularly in the areas of mental health, chemical addiction, weight management, and also stroke, cardiac, and pulmonary rehabilitation, there are no reports of such studies related to Tai Chi programs. Considering the propensity of people in Hong Kong and the Chinese mainland to do Tai Chi, which is already a social phenomenon throughout Asia and increasingly in western countries, and considering the supportive scientific evidence, community-based programs of Tai Chi have the potential to provide public health benefits in the well elderly as well as in people who have chronic degenerative or progressive conditions. Programs such as Tai Chi that are both culturally relevant and sensitive could yield considerable benefit to participants and to the health care system with respect to wellness, health promotion, and disease management, and with respect to potential cost savings. This belief is consistent with the emerging trend in industrialized countries away from a primary focus on individual health care to population-based health promotion. Attention now is on health care that has a community perspective, on evidence-based practice, on global as well as individual outcomes, and on prevention. 25 Unlike the benefits of other types of exercise, the benefits of Tai Chi that have been identified under laboratory conditions may be less generalizable when Tai Chi is taught in the community. Why does community Tai Chi provide such a different pattern of benefits? First, unlike Tai Chi, conventional aerobic and strengthening exercises lend themselves to quantification and prescription. Specifically, the type of exercise, its intensity, duration, and frequency, hence, workload, can be specifically quantified and controlled to elicit specific physiologic responses. Second, unlike conventional aerobic and strengthening exercises typically taught in classes in the West,

2 620 COMMUNITY TAI CHI PROGRAM EFFECTIVENESS, Jones carried out the study, and they conducted the program as they normally would. We provided no direction regarding the teaching of the course. Offering encouragement to the participants to attend regularly and practice on their own at home also was the responsibility of the community center and the Tai Chi masters. The program was conducted at 7:30 AM, for 1.5 hours, 3 times weekly, for 12 weeks. Prior to the commencement of the program, all subjects were invited to the office of the local residents association for baseline measurements. The study was explained and written consent was obtained from each subject before data collection. Seven research assistants were trained in the procedures and collected the data under the direct supervision of the investigators. Fig 1. A Tai Chi assistant providing personal instruction during the class. Tai Chi is a complex system of movements that requires body awareness, motor coordination, and agility. Thus, it takes a variable amount of time to master, and the degree of proficiency can be expected to vary according to these individual variables as well as to one s capacity for motor learning. Third, because of the sequence of Tai Chi movement patterns and the various styles of this exercise form, its intensity is more variable than that of conventional aerobic and strengthening classes. The overall aim of the present study was to examine the effectiveness of a community-based Tai Chi program in Hong Kong, and its feasibility and benefit as a public health strategy. Specifically, the objectives were 2-fold: (1) to determine whether such a program has effects comparable to those reported for Tai Chi in published laboratory studies, and (2) to determine whether it is practical and effective as a public health strategy. METHODS Community Initiative Because the evaluation of the Tai Chi program was a collaborative initiative between a residents association in Hong Kong and the university, all components of the study were based at the offices of the association, and in the building estates they administered. Thus, established field tests were selected so that these could be conducted at the residents association office for the convenience of the participants, and also to facilitate community involvement and participation of the residents association office staff. General Procedures The research protocol was approved by the university s departmental Research Ethics Committee. Subjects provided informed signed consent. The study consisted of 2 phases. In phase 1, a sample of convenience of subjects with no formal experience in Tai Chi was recruited through poster advertisements circulated by the local residents association. The program was instructed by a qualified Tai Chi master with 4 Tai Chi masters as assistants. The Cheng 119 style (a beginner s level with a moderate level of intensity) was selected by the master. The qualified and experienced master and assistants were hired by the local residents association. We used the masters assigned to the program by the community center where we Specific Procedures Dependent variables of interest included lung function measured with a hand-held spirometer a designed for reliable measures in the field: forced vital capacity (FVC), forced expiratory flow rate in 1 second (FEV 1 ), peak expiratory flow rate (PEFR), and mid expiratory flow rate; oxygen saturation (measured by a pulse oximeter b ), exhaled carbon monoxide levels (measured with a carbon monoxide meter c ), resting heart rate, and diastolic (DBP) and systolic blood pressure d (SBP); index of balance (distance reached by the forward arm in a fixed standing position) (Functional Reach Test 26 [FRT]); spinal flexion (distance reached by the arms with knees straight in a sitting position) (Sit-and-Reach Test [SRT]) 27 ; shoulder flexion (distance between middle fingers of the left and right hands at the back with the left and then with the right arm up in the zipper test) 27 ; and hand grip strength (measured with a Jamar hydraulic hand dynamometer e ). The basic pulmonary function variables were measured before and after the 12-week program. All other parameters were measured before the program began, after 6 weeks, and after 12 weeks of participation in the program. Subjects also completed a questionnaire on the details of their activity levels and exercise before and after the 12-week program. On completion of the program, participants completed a separate questionnaire about their experience in the program and their subjective perception of the benefits of Tai Chi. In phase 2, experienced practitioners, who had previously taken the Tai Chi course through the residents association and had continued to practice for at least 6 months, were invited to undergo the battery of tests and measures that were used for the novice practitioners in phase 1. This enabled us to compare physiologic differences between the experienced and inexperienced Tai Chi practitioners before both began the 12-week Tai Chi program. Data Analysis Data were analyzed using SPSS, version 10.0, f for Windows. Descriptive analyses were used to summarize and display subjects descriptive and outcome variables. Repeated-measures analyses of variance (ANOVAs) identified differences in the means for each variable over time (baseline, 6wk, 12wk). Paired t tests were used for post hoc comparisons. Paired t tests were also used to determine differences in the lung function parameters, which were measured twice once at baseline and again at the end of the 12-week program. Independent t tests were used to examine differences in baseline parameters measured between the novice and the experienced groups. The level of significance was set at.05 for all analyses. A Bonferroni adjustment was applied to those findings that were statistically significant over time. Descriptive analyses including frequency counts were used to summarize the responses to the

3 COMMUNITY TAI CHI PROGRAM EFFECTIVENESS, Jones 621 Table 1: Descriptive Data of the Sample of Novice and Experienced Tai Chi Groups at Baseline Variable Novice Group (n 60) activity questionnaire and the questionnaire related to the participant s satisfaction with and practicalities of the program. RESULTS Experienced Group (n 49) Mean age SD (y) Sex (n) 10M/50F 13M/36F Mean BMI SD Smoking status (n) Nonsmoker Ex-smoker 5 1 Smoker 2 1 Chronic conditions (n) Heart condition 3 4 Lung condition 4 2 Diabetes 0 1 Thyroid disease 2 1 Arthritis Hypertension 8 6 Stroke 4 0 Other conditions Abbreviations: BMI, body mass index; F, female; M, male; SD, standard deviation. Baseline Comparisons In phase 1, which consists of the pre- and posttraining comparison of the novice practitioners, 60 subjects (50 women, 10 men) registered for the program. Table 1 summarizes the descriptive and health status of the subjects in both the novice group, who signed up for the 12-week Tai Chi program, and the experienced control group, who were assessed at baseline for comparison with the novice group. Phase 2 consisted of the baseline comparison between the novice practitioners and the experienced practitioners. The novice and experienced practitioners were comparable in terms of age, body mass, and history of chronic conditions. In the novice group, 9 subjects did not complete the 12-week program, and the average attendance for the remaining 51 subjects (42 women, 9 men) was 81%. The age of the 51 participants standard deviation averaged years (range, 29 72y). Fig 2. Post hoc tests for variables shown to be significant over the 3 times (paired t tests with Bonferroni adjustment). *P.003; P.001; P<.001. Changes Over Time The results of the repeated-measures ANOVAs for the variables measured at baseline, 6 weeks, and 12 weeks (table 2) showed increases in stability (based on the FRT), spinal flexion (based on the SRT), left shoulder flexion (based on the zipper test with left arm in the up position), and aerobic conditioning (based on resting heart rate). Figure 2 summarizes the results of the post hoc tests for each variable that was significant over time (ie, the SRT, FRT, zipper test with left arm up, resting heart rate), and indicates where there were differences over the 3 testing points after Bonferroni adjustment. Postural stability (based on the FRT) improved progressively over the Tai Chi program (F 2, , P.001). Post hoc tests showed that only the mean functional reach score at 12 weeks (t , P.01) was greater when compared with baseline and with the 6-week score (t , P.003). Spinal flexion (based on the SRT) also showed improvement (F 2, , P.001). The reach scores at 6 weeks (t , P.001) and 12 weeks (t , P.001) were better than those at baseline. With respect to shoulder flexion (based on the zipper test), left shoulder flexion improved compared with baseline, and exceeded changes in right shoulder flexion (F 2, , P.041). At 12 weeks, right shoulder flexion (left arm up) was increased compared with Table 2: Variables Measured at Baseline, at 6 Weeks, and at the End (12wk) of the Tai Chi Program for the Novice Group Variable Baseline After 6 Weeks After 12 Weeks F P* Hand grip strength (kg) (n 43) Sit and reach (cm) (n 44) <.001 Functional reach (cm) (n 45) Zipper with left arm up (cm) (n 44) Zipper with right arm up (cm) (n 44) Resting heart rate (beats/min) (n 45) Resting SBP (mmhg) (n 45) Resting DBP (mmhg) (n 45) Resting respiratory rate (breaths/min) (n 42) Oxygen saturatio (n 45) Exhaled carbon monoxide (ppm) (n 42) NOTE. Values are mean SD. *Boldface denotes statistical significance.

4 622 COMMUNITY TAI CHI PROGRAM EFFECTIVENESS, Jones Table 3: Lung Function Variables Measured at Baseline and at the End (12wk) of the Tai Chi Program for the Novice Tai Chi Group (n 47) Variable Baseline At 12 Weeks t P* FVC (L) FEV 1 (L/s) Peak inspiratory flow rate (L/s) PEFR (L/s) Mid expiratory flow rate (L/s) NOTE. Values are mean SD. *Boldface denotes statistical significance. baseline (t , P.05). Resting heart rate at baseline and 12 weeks was the same, despite slight increase at 6 weeks (F 2, , P.013). Post hoc tests showed that the heart rate at 6 weeks was higher than that measured at baseline and at 12 weeks (P.05). For the lung function measures evaluated at baseline and at 12 weeks (table 3), only the PEFR was increased by the end of the program (t , P.019). The average age of the subjects in the experienced group was years (range, 39 71y). Results of the independent t tests used to compare the novice and experienced groups at baseline (table 4) demonstrated significant differences in spinal flexibility (based on the SRT; t , P.04), in aerobic conditioning (based on the resting heart rate; t , P.04), and resting SBP (t , P.02). Satisfaction Survey Forty-three participants completed the satisfaction survey administered at the end of the program. Approximately half of the respondents learned about the class from posters distributed in the neighborhood. Most of the others learned of the program from a family member, friends, or the community office. The majority (93%) of respondents reported participating in the Tai Chi class because of its perceived health benefits. A small number attended the class for social reasons (14%). For those who missed classes, most of them missed due to health reasons (21%), family obligations (19%), or conflicts with work (10%). Having the Tai Chi class at a location in the community where the participants resided was an incentive for 41 of the participants to participate (95%). Most (81%) of the participants who attended the 12-week program had never practiced Tai Chi before and a majority (63%) thought that a 12-week program is not long enough for learning Tai Chi. After the 12-week program, all respondents agreed that their knowledge of Tai Chi had increased either a little (14%), a moderate amount (65%), or a lot (21%). Almost all (95%) stated that they would continue to practice Tai Chi. The postprogram satisfaction survey also asked participants about the health benefits they believed would result from the 12-week Tai Chi program. The responses to these questions are shown in table 5. Participating in the Tai Chi program increased the awareness of most (86%) participants of their health status and lifestyle, resulting in many (67%) of them, at the end of the program, exercising more than they had before the start of the program. Nine percent of the participants reported changing their diet to eat more healthy foods, 12% reported losing weight, and 23% reported being able to relax more. More than one third of the participants reported that family members observed some or significant change in their health and well-being. Last, more than 90% of the participants who completed the satisfaction survey reported that they would encourage their family and friends to join a Tai Chi class. All but 2 participants reported they would join a more advanced class if it were offered. Overall, the satisfaction with the 12-week Tai Chi Table 4: Comparison of Parameters Between Novice and Experienced Tai Chi Groups at Baseline Variable Novice Group (n 60) Experienced Group (n 49) t P* Age (y) BMI (kg/m 2 ) Hand grip strength (kg) Sit and reach (cm) Functional reach (cm) Zipper with left arm up (cm) Zipper with right arm up (cm) Resting heart rate (beats/min) Resting SBP (mmhg) Resting DBP (mmhg) Oxygen saturatio Exhaled carbon monoxide (ppm) FVC (L) FEV 1 (L/s) PEFR (L/s) Mid expiratory flow rate (L/s) NOTE. Values are mean SD. *Boldface denotes statistical significance.

5 COMMUNITY TAI CHI PROGRAM EFFECTIVENESS, Jones 623 Table 5: Self-Reported Benefits of the 12-Week Tai Chi Program (n 43), by the Self-Satisfaction Survey The Benefits I Received From the Tai Chi Program Included: program was rated as excellent (56%) or at least very good (37%). The involvement of both the novice and experienced participants in other types of exercises is shown in table 6. At the end of the 12-week Tai Chi program, the novice group was again surveyed about exercise habits. Not only were they, at that point, practicing Tai Chi, the proportion of those who practiced qi gong, an exercise practice that coordinates breathing control, had increased (from 13% to 23%). However, the proportion of those who participated in activities other than Tai Chi had decreased by the end of the 12-week program (see table 6). DISCUSSION A Great Deal, Somewhat, Feeling stronger 23 (53.5) 20 (46.5) Feeling more flexible 31 (72.1) 12 (27.9) Feeling like I have more energy 29 (67.4) 14 (32.6) Having more endurance when I exercise 20 (46.5) 23 (53.5) Feeling healthier 29 (67.4) 14 (32.6) Feeling that I can do more at home or at work 19 (44.2) 24 (55.8) Feeling happier 31 (72.1) 12 (27.9) Sleeping better 16 (37.2) 27 (62.8) Having less stress 16 (37.2) 27 (62.8) Community and Laboratory-Based Tai Chi Programs: Comparison of Physiologic Effects To date, no previous study has assessed in detail the effects of Tai Chi taught to inexperienced practitioners in a community-based program. Compared with many laboratory studies that have examined a limited range of variables related to strength, flexibility, or cardiovascular responses, we studied several variables that crossed physiologic systems using common, established field tests. Exercise generally has little effect on lung function other than variables that are effort dependent. The results of our study confirmed that in healthy persons most measures of pulmonary function do not change in response to aerobic types of exercise. The exception is the increase we found in PEFR, which may reflect increased respiratory muscle strength. Hong et al 6 reported a cardiovascular effect of Tai Chi in older people (68y) based on a 3-minute step test. Because of the practical and resource issues related to exercise testing the 60 participants in the class, 28 the primary indices of cardiovascular fitness used in the study were resting heart rate and blood pressure. These did not change following the Tai Chi program. However, heart rate was lower for the experienced practitioners when compared with the inexperienced practitioners before the program, supporting the findings of Hong 6 that Tai Chi practitioners are generally better conditioned aerobically. Heart rate alone, however, as an index of physical conditioning should be interpreted cautiously. Although the DBP was higher for the experienced group, DBP compared with SBP has recently been reported to be less implicated in the etiology of heart disease and stroke. 29 Of the variables most studied before and after a Tai Chi program, balance and stability in older adults are most common. 6,10,11,30,31 The results of the present study using the FRT to provide a previously validated index of standing balance, 27 the distance reached by the forward arm in a fixed standing position, supported the results of previous studies showing the benefit of Tai Chi on postural control and balance. Wolf et al 10 reported that after a combination of classes (15 weekly sessions) and home practice (15min at least twice daily), fear of falling and the rate of falling in subjects who were older than 70 years were reduced (48% decrease in falls). Wolfson et al 32 reported (in a sample of 110 subjects over the age of 80 years) strength gains as well as balance improvement after practicing Tai Chi for 45 minutes 3 times weekly for 3 months. The effect of the community-based Tai Chi program on postural stability is an important outcome with respect to public health. Postural control and balance are essential in fall prevention, a primary concern in older people who are prone to osteoporosis, delayed healing, and prolonged hospital stays. In elderly persons, loss of spinal agility and flexion may compromise both balance and ventilatory response to exercise. The distance reached by the arms with knees straight in a sitting position (the SRT) has been validated previously as a measure of spinal flexion. Spinal flexion was greater both after Tai Chi training, and was also greater in the experienced practitioners when compared with the novices at baseline. Thus, our results are compelling regarding the effects of Tai Chi on spinal mobility, and they support the laboratory-based findings of improved flexibility reported by Hong 6 and Ross 33 and colleagues. Joint stiffness and reduced joint range of motion (ROM) are often associated with aging. We also observed increased left shoulder flexion (distance between middle fingers of the left and right hands at the back with the left arm up in the zipper test) following the program. There was no difference in this variable, however, between the experienced and inexperienced groups at baseline. These results support that Tai Chi can improve joint ROM. This effect, however, may be greater in the lower extremities, because Tai Chi stresses these joints to a greater extent. We did not measure lower-extremity joint ROM in this study. Tai Chi has been reported to improve strength and endurance of the peripheral muscles of older (mean, 61y) adults. 5 For a field test measure, we selected hand grip strength because of its association with general strength in the elderly, 34 and because this measure has well-documented reliability. 35 Grip strength did not change when comparing the novice group before and after the Tai Chi program, or between the novice group and experienced group at baseline. Had the Tai Chi style been more intense, or the power of the study greater, this result may have become significant. Table 6: Exercise Habits of the Experienced Group at Baseline, and Novice Group at Baseline and After the 12-Week Tai Chi Program Group Qi Gong, Jogging, Swimming, Stretching, Experienced (n 49) at baseline 3 (6.1) 6 (12.2) 5 (10.2) 8 (16.3) 8 (16.3) Novice (n 60) at baseline 8 (13.3) 18 (30.0) 15 (25.0) 24 (40.0) 11 (18.3) Novice (n 47) after 12-week program 11 (23.4) 12 (25.5) 8 (17.0) 11 (23.4) 5 (10.6) Others,

6 624 COMMUNITY TAI CHI PROGRAM EFFECTIVENESS, Jones The postprogram satisfaction survey supported the conclusion that the participants had experienced psychologic benefits and considerable satisfaction with the program and that they were motivated to continue practicing Tai Chi and were interested in taking more advanced levels. Ross et al 33 reported that Tai Chi can enhance the mood of elderly persons. Detailed study of the psychologic benefits of Tai Chi is needed. Such benefit may be anticipated based on what is known about the psychologic benefits of aerobic-type exercise in general. However, the degree to which Tai Chi may elicit psychologic benefit versus the social participation in a class needs to be determined. Comparable to other forms of exercise, the benefits of Tai Chi only remain so long as the exercise is continued. 10 This finding supports the need for continued practice to maintain the life-long health and physiologic benefits. Public Health Implications With the escalating trend toward diseases of civilization, that is, those associated with Western lifestyles, people in Asian countries are less protected by active lifestyle and wholesome diets. Culturally relevant forms of exercise and activity must be investigated to increase adherence to exercise programs and increase activity levels. Tai Chi is one such form of exercise that is practiced widely in Asian countries. However, unlike forms of exercise that are common in Western countries, Tai Chi has many styles, each with varying intensities. The level of proficiency also determines the degree of exercise effect. Studies in the literature do not consistently discriminate among the many styles of Tai Chi. The degree to which different styles have differential health effects has not been established. Our study involved the evaluation of a Tai Chi class that was large ( 50 participants on any given day). Participants were generally younger than we had predicted. Despite this, we still found that the moderate exercise intensity of the Cheng 119 style used for beginners provided exercise responses consistent with a long-term aerobic exercise program. Such classes can service a large number of participants with minimal resources. The program was scheduled in a public place, and the cost for the Tai Chi master and assistants was covered by the nominal fee for the class. Being community-based, the program was run on a cost-recovery basis. Attendance in classes is associated with important social benefits, including being with friends or family members, meeting new people, receiving encouragement from others, and the satisfaction of mastering a complex form of exercise. With continued practice, one can continue to improve Tai Chi proficiency over one s lifetime, which provides additional incentive. Community-based exercise programs have advantages other than the indirect physical and psychosocial benefits. People attending an exercise class in a community setting can be targeted for other health education information, such as antismoking campaigns, nutritional campaigns, stress management, and other regional health concerns. CONCLUSIONS Tai Chi learned in a community-based program (performed for 1.5h, 3 times weekly, for 12wk) provides many of the same physiologic benefits reported by researchers doing controlled, laboratory-based, scientific studies. Despite the variability in intensity inherent in the complex, coordinated movements of Tai Chi and the less tightly controlled practice schedule, the results of our community-based study were comparable to reports from the laboratory. We conclude that Tai Chi is feasible and potentially economical as a public health initiative. Our program required 1 Tai Chi master with 4 assistants who circulated during program sessions to provide individual attention to as many as 60 participants. The response of the participants to the program was highly positive. Many were interested in taking the next higher level of Tai Chi, and would recommend such a program to family and friends. Tai Chi is widely accepted in Asia and increasingly in the West as a health-promoting activity that can be practiced at any age in any setting, and requires no equipment. The potential cost effectiveness of Tai Chi makes it an ideal choice for public health initiatives globally. Acknowledgment: We gratefully acknowledge Lai Chun Hei and Wilson Lam Wai Shun, research assistants for this project, who helped coordinate data collection and collect the data, as well as perform preliminary data analysis. 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