title: Hemodynamic responses to a community-based Tai Chi exercise intervention in ethnic Chinese adults with cardiovascular disease risk factors.
abstract: BACKGROUND
  Cardiovascular disease (CVD) is the leading cause of death among older adults worldwide, including Europe, Asia, and North America. In the United States (US), CVD is also the leading cause of death among Asian-Americans. Physical activity has been shown to reduce CVD risk factors. Reduction in blood pressure (BP) in response to Tai Chi (TC) exercise in persons with CVD risk factors have been reported, though not in ethnic Chinese living in the US.
  
  
  OBJECTIVE
  Hemodynamic responses to a 12-week community-based TC exercise intervention among ethnic Chinese with CVD risk factors were examined.
  
  
  METHODS
  Quasi-experimental design. Ethnic Chinese > 45 years old with at least 1 major CVD risk factor, living in the San Francisco Bay Area, attended a TC intervention three times a week for 12 weeks. A 2-min step-in-place test assessed aerobic endurance. BP and heart rate were measured at rest, and within 1-min after the step-test. Data were collected at baseline, 6 and 12 weeks.
  
  
  RESULTS
  A total of 39 subjects (69% women), 66 +/- 8.3 years old, with hypertension (92%), hypercholesteremia (49%), and/or diabetes (21%), and 1 current smoker participated. Adherence to the intervention was high (87%). Subjects were sedentary at baseline, though had a statistically significant improvement in aerobic endurance over-time (eta2 = 0.39). At baseline, the average BP at rest was 150/86, while BP in response to the step-test was 178/99. Clinically and statistically significant reductions in BP at rest (131/77), and in response to the step-test (164/82) were found over 12 weeks of TC (p < 0.01). No significant change in heart rate was observed.
  
  
  CONCLUSIONS
  This innovative, culturally relevant, community-based 12-week TC exercise intervention, appealed to Chinese adults with CVD risk factors, with significant reductions in BP and improvement in aerobic endurance. Given the number of persons estimated to have HTN and other CVD risk factors, the identification of new approaches to improve health, combined with risk factor reduction is needed. This is particularly important, given the rise in HTN among adults in the US and the associated public health burden of HTN. TC has the potential to reduce expenditures associated with CVD by facilitating a lifestyle that promotes physical activity, while remaining a low-tech, low-cost alternative to exercise.
authors.affiliation: Stanford Prevention Research Center, School of Medicine, Stanford University, Hoover Pavilion, MC 5705, 211 Quarry Road, Room N229, Stanford, CA 94305-5705, USA. rpiliae@stanford.edu
authors.forename: Ruth E
authors.initials: RE
authors.lastname: Taylor-Piliae
authors.forename: William L
authors.initials: WL
authors.lastname: Haskell
authors.forename: Erika Sivarajan
authors.initials: ES
authors.lastname: Froelicher
mesh_terms: D000328:Adult; D001213:Asian / Q000208:ethnology / Q000706:statistics & numerical data; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000208:ethnology* / Q000209:etiology / Q000517:prevention & control*; D002681:China / Q000208:ethnology; D003151:Community Health Centers; D003920:Diabetes Mellitus / Q000517:prevention & control; D005240:Feasibility Studies; D005260:Female; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D006937:Hypercholesterolemia / Q000150:complications / Q000517:prevention & control; D006973:Hypertension / Q000150:complications / Q000517:prevention & control; D008297:Male; D010807:Physical Endurance; D010865:Pilot Projects; D015397:Program Evaluation; D040242:Risk Reduction Behavior; D012495:San Francisco; D012907:Smoking / Q000009:adverse effects; D000074606:Smoking Prevention; D026302:Tai Ji / Q000458:organization & administration*