Tai Chi Beneficial For Improving Aerobic Capacity

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Review

Is tai chi beneficial for improving aerobic capacity? A systematic review
M S Lee,1,2 E-N Lee,3 E Ernst2
Department of Medical Research, Korea Institute of Oriental Medicine, Daejeon, South Korea; 2 Complementary Medicine, Peninsula Medical School, Universities of Exeter & Plymouth, Exeter, UK; 3 Departmentof Nursing, DongA University, Busan, South Korea Correspondence to: Dr M Soo Lee, Department of Medical Research, Korea Institute of Oriental Medicine, 461-24, Jeonmin-dong, Yuseong-gu,Daejeon 305-811, South Korea; drmslee@gmail. com Accepted 28 October 2008 Accepted for Online First 19 November 2008
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ABSTRACT Tai chi has been claimed to generate beneficial effects with respect to a widerange of diseases. The purpose of this systematic review was to evaluate evidence from randomised clinical trials (RCTs) testing the effectiveness of tai chi for increasing aerobic capacity. Systematic searches were conducted on 14 electronic databases without restrictions on population characteristics or the language of publication. The outcome measures considered for inclusion were changes inmaximal oxygen consumption as a test for aerobic capacity. Five RCTs met all inclusion criteria. Three RCTs compared the effects of tai chi with no treatment. The meta-analysis failed to show an effect of tai chi on aerobic capacity compared with sedentary controls (n = 151, weight mean difference, ml/kg/min, 0.50, 95% CI 21.14 to 2.15, p = 0.55). Two RCTs compared tai chi with conventional physicalexercise including brisk, low intensity and moderate intensity walking, and aerobic exercise. The results show that tai chi was not statistically significantly superior to physical exercise. In conclusion, the existing evidence does not suggest that regular tai chi is an effective way of increasing aerobic capacity.
Maximal oxygen uptake or consumption is an important determinant of enduranceperformance, which represents a measure of cardiovascular capacity for an individual at a given degree of fitness and oxygen availability.1 It is also an independent risk factor for all-cause and cardiovascular disease mortality.2 Tai chi is a form of complementary therapy with similarities to aerobic exercise which, according to some of its proponents, improves cardiovascular fitness.1 2 It comprises aseries of postures linked by gentle and graceful movements.3 Several reviews have suggested that tai chi is beneficial for improving cardiorespiratory function including aerobic capacity.4–7 However, these reviews had several limitations, such as no systematic approach and the use of meta-analysis despite statistical and clinical heterogeneity of the primary data. The value of tai chi as a meansof improving aerobic capacity therefore remains uncertain. The aim of this systematic review is to clarify this issue by critically evaluating all RCTs of tai chi for improving aerobic capacity.

Information, DBPIA, Korea Institute of Science and Technology Information, Research Information Center for Health Database, KoreaMed, and Korea National Assembly Library) and four Chinese databases(China Academic Journal, Century Journal Project, China Doctor/ Master Dissertation Full text DB, China Proceedings Conference Full text DB). The search terms used were based around two concepts. Concept one included all terms for tai chi and concept two included terms for aerobic capacity. Two concepts were combined using the Boolean operator AND. Korean and Chinese terms for tai chi and aerobiccapacity were used in the Korean and Chinese databases. In addition, our own files and our review journal (FACT—Focus on alternative and complementary therapies, from 1996 to 2008) were manually searched. The references of all located articles and the proceedings of the first International Conference of Tai Chi for Health (December 2006, Seoul, South Korea) were handsearched for further relevant...