Abstract
Heart disease is a chronic condition needing lifetime secondary prevention measures to decrease morbidity and mortality, and to improve quality of life. Cardiac rehabilitation exercise training, one aspect of cardiac recovery, traditionally includes some form of aerobic fitness and, more recently, muscle strength training to improve exercise tolerance. Tai chi, widely practiced in China for centuries, is a popular form of exercise among older Chinese persons associated with enhanced well-being and health among traditional Chinese practitioners. Recent research has reported improvement in cardiorespiratory function, balance and postural stability, fall prevention, and stress reduction. A review of the literature suggests potential benefits from tai chi exercise performed as an adjunct to cardiac rehabilitation exercise training. Tai chi is cost-effective and facilitates a lifestyle of health-related behavior practices.
Despite advances in medicine and clinical care, heart disease continues to be the leading cause of morbidity and mortality in the United States. 1-3 Global cardiovascular disease (CVD) mortality accounts for one third of all deaths, with two thirds of those deaths occurring in developing countries. 4,5 Projected global CVD deaths are expected to rise significantly, increasing CVD burden in developing countries over the next two decades. In developing countries alone, CVD mortality currently represents 24.5% of all deaths, and an increase to 34% is predicted by 2020. 2 In China, death attributable to CVD rose from 12.1% in 1957 to 35.8% in 1990. 2 Cigarette smoking among males in China reportedly exceeds 60% and is expected to increase. 6 In Hong Kong, diseases of the circulatory system accounted for 25% of all deaths in 1998, with heart disease listed as the second leading cause of death, representing 61% of that mortality. 7 There is concern that the prevalence of heart disease will continue to rise because of increased affluence and adoption of a Westernized lifestyle, with increased levels of smoking, high cholesterol intake, stress, and a sedentary lifestyle among Chinese persons living in Hong Kong, as well as other affluent cities around the world. 8 Moreover, ethnic Chinese are the largest group of Asian immigrants in the United States, and heart disease is listed as the leading cause of mortality among them, representing 29.4% of all deaths. 9
Secondary prevention through cardiac rehabilitation can contribute significantly to improving the functional status of known cardiac patients, modifying coronary risk factors, and improving quality of life while reducing mortality and morbidity. 10 Findings have shown secondary prevention to be effective for a variety of cardiac conditions including angina pectoris (stable), myocardial infarction, coronary bypass surgery, intracoronary revascularization (angioplasty, stenting, rotablator, laser angioplasty), valve replacement, and heart failure. 10-12 Cardiac rehabilitation exercise training, one element of cardiac recovery, has been shown to decrease cardiac risk factors by improving blood lipid profile, symptoms associated with angina and heart failure, and psychosocial well-being; by reducing stress, blood pressure, and mortality; and by aiding weight control. 10,11 Research evidence also has found that cardiac rehabilitation exercise training leads to improvements in various measures of psychological status and functioning. 10,13 Moreover, physical fitness among persons qualifying for cardiac rehabilitation has been shown to serve as an independent predictor of mortality. 12,14
The most common types of exercise training have included some form of aerobic fitness, and more recently muscle strength training, to improve exercise tolerance. 14,15 Exercise intensity of 50% to 70% of the predicted maximum heart rate is safe and appropriate for coronary patients. 11 Light to moderate physical activity has been reported to reduce coronary heart disease mortality. 16 Tai chi, a traditional Chinese exercise that originated in China hundreds of years ago, is based on principles found in the ancient Chinese philosophies of Confucianism, Taoism, and Buddhism. As a healing art, it is widely used by Chinese doctors to treat conditions of hypertension, stress, depression, mental strain, chronic indigestion, insomnia, and arthritis. Tai chi is associated with enhanced well-being and health among traditional Chinese practitioners. 17,18 Only recently has attention been given by the West to its potential health benefits. 19-21 Recent research has reported improvements in cardiorespiratory function, balance and postural stability, fall prevention, and stress reduction. 22 Tai chi requires no special facility or expensive equipment, and can be performed either individually or in groups. Tai chi movements are ideally suited for persons of all ages, regardless of previous exercise experience and aerobic capacity. 17