There is evidence, though sometimes controversial, that exercise improves many aspects of cardiovascular health including reduced incidence of coronary heart disease, stroke, and hypertension. [1], [2], [3] The majority of this research has focused on the impact of vigorous or moderate exercise. Less is known about the cardiovascular benefits of lower intensity exercise, such as Tai Chi.



A growing body of evidence suggests Tai Chi practice, even over short periods of time, may improve cardiovascular health. Depending on how it is practiced, Tai Chi has been characterized as a low to moderate intensity exercise. Three studies are briefly discussed to illustrate the types of evidence available to evaluate the impact that Tai Chi may have on components of cardiovascular health. Young et al. [4]conducted a well designed, randomized controlled trial with 62 subjects that compared the effects of aerobic exercise versus Tai Chi on blood pressure in mildly hypertensive older adults. Over the 12-week study period, Tai Chi was observed to be equally effective as aerobic exercise in reducing both systolic and diastolic blood pressure. Lai et al. [5] conducted a longitudinal, prospective study comparing two-year trends in cardiorespiratory function of a group of elderly Tai Chi practitioners (n=45) with an age-matched, sedentary control group (n=39). Their results suggest that Tai Chi may delay the decrease in aerobic capacity usually found with aging. Lan et. al. [6] conducted a cross-sectional, case-controlled study to evaluate the health benefits of long-term, geriatric Tai Chi practitioners. Cycle ergometry revealed that peak oxygen uptake was greater for Tai Chi practitioners (n=41) compared to age-matched sedentary subjects (n=35). No adverse effects related to the short- or long-term practice of Tai Chi were reported in any of these studies. These and other studies are summarized in reviews by Li et al. [7] and Lan et al.[8].



In summary, these and related studies suggest that Tai Chi is a safe exercise, even for frail elders, and may be beneficial to various aspects of cardiovascular health. It requires no specialized equipment, is relatively inexpensive and can be taught/learned in a group setting. Tai Chi appears to elicit a cardiovascular response equivalent to that associated with moderate intensity exercise, and as such meets the American College of Sports Medicine, American Heart Association, and Centers for Disease Control recommendations for daily performance of low- to moderate-intensity activities [9]. However, studies have yet to investigate whether the physiological mechanisms by which Tai Chi impacts cardiovascular health are the same as those believed to relate to more typical endurance and aerobic training[10].

Taylor-Piliae RE, Haskell WL, Stotts NA, Froelicher ES.

Stanford Prevention Research Center, Stanford University School of Medicine, Stanford University, Calif, USA.

CONTEXT: Declines in physical performance are associated with aging and chronic health conditions. Appropriate physical activity interventions can reverse functional limitations and help maintain independent living. Tai chi is a popular form of exercise in China among older adults. OBJECTIVE: To determine whether tai chi improves balance, muscular strength and endurance, and flexibility over time. DESIGN: Repeated measures intervention; data collected at baseline, 6 weeks, and 12 weeks. SETTING: Community center in the San Francisco Bay Area. PARTICIPANTS: Thirty-nine Chinese adults with at least 1 cardiovascular disease (CVD) risk factor. INTERVENTIONS: A 60-minute tai chi exercise class 3 times per week for 12 weeks. MAIN OUTCOME MEASURES: A battery of physical fitness measures specifically developed for older adults assessed balance, muscular strength and endurance, and flexibility. RESULTS: Subjects were 65.7 (+/- 8.3) years old, Cantonese-speaking (97%) immigrants, with 12 years or less of formal education (87%) and very low income (67%). Reported CVD risk factors were hypertension (92%), hypercholesteremia (49%), diabetes (21%), and 1 current smoker. Subjects were below the 50th percentile of fitness at baseline compared to age- and gender-specific normative US data. Statistically significant improvements were observed in all balance, muscular strength and endurance, and flexibility measures after 6 weeks, and they increased further after 12 weeks. CONCLUSIONS: Tai chi is a potent intervention that improved balance, upper- and lower-body muscular strength and endurance, and upper- and lower-body flexibility in these older Chinese adults. These findings provide important information for future community-based tai chi exercise programs and support current public health initiatives to reduce disability from chronic health conditions and enhance physical function in older adults.

PMID: 16541997 [PubMed - indexed for MEDLINE]

Taylor-Piliae RE, Haskell WL, Waters CM, Froelicher ES.

Stanford Prevention Research Center, School of Medicine, Stanford University, Stanford, California 94305-5705, USA. This email address is being protected from spambots. You need JavaScript enabled to view it.

AIM: This paper reports a study to examine change in psychosocial status following a 12-week Tai Chi exercise intervention among ethnic Chinese people with cardiovascular disease risk factors living in the United States of America. BACKGROUND: Regular participation in physical activity is associated with protection against cardioavascular disease, and improvements in physical and psychological health. Increasing amounts of scientific evidence suggests that mind-body exercise, such as Tai Chi, are related to improvements in mental health, emotional well-being, and stress reduction. No prior study has examined the effect of a Tai Chi exercise intervention on psychosocial status among people with cardiovascular disease risk factors. METHODS: This was a quasi-experimental study. Participants attended a 60-minute Tai Chi exercise class three times per week for 12 weeks. Data were collected at baseline, 6 and 12 weeks following the intervention. Psychosocial status was assessed using Chinese versions of Cohen's Perceived Stress Scale, Profile of Mood States, Multidimensional Scale of Perceived Social Support, and Tai Chi exercise self-efficacy. RESULTS: A total of 39 participants, on average 66-year-old (+/-8.3), married (85%), Cantonese-speaking (97%), immigrants participated. The majority were women (69%), with < or =12 years education (87%). Statistically significant improvements in all measures of psychosocial status were found (P < or = 0.05) following the intervention. Improvement in mood state (eta2 = 0.12), and reduction in perceived stress (eta2 = 0.13) were found. In addition, Tai Chi exercise statistically significantly increased self-efficacy to overcome barriers to Tai Chi (eta2 = 0.19), confidence to perform Tai Chi (eta2 = 0.27), and perceived social support (eta2 = 0.12). CONCLUSIONS: Tai Chi was a culturally appropriate mind-body exercise for these older adults, with statistically significant psychosocial benefits observed over 12-weeks. Further research examining Tai Chi exercise using a randomized clinical trial design with an attention-control group may reduce potential confounding effects, while exploring potential mechanisms underlying the relaxation response associated with mind-body exercise. In addition, future studies with people with other chronic illnesses in all ethnic groups are recommended to determine if similar benefits can be achieved.

PMID: 16629916 [PubMed - indexed for MEDLINE]