The effects of aerobic exercise and T'ai Chi on blood pressure in older people: Results of a randomized trial

OBJECTIVE: To compare the effects on blood pressure of a 12-week moderate-i ntensity aerobic exercise program and a T'ai Chi program of light activity. DESIGN: A randomized clinical trial. SETTING: A suburban clinic in the Baltimore, MD, area. PARTICIPANTS: Sixty-two sedentary older adults (45% black, 79% women, aged greater than or equal to 60 years) with systolic blood pressure 130-159 mm Hg and diastolic blood pressure < 9.5 mm Hg (not on antihypertensive medica tion). INTERVENTION: Participants were randomized to a 12-week aerobic exercise pr ogram or a light intensity T'ai Chi program. The goal of each condition was to exercise 4 days per week, 30 minutes per day. MEASUREMENTS: Blood pressure was measured during three screening visits and every 2 weeks during the intervention. Estimated maximal oxygen uptake and measures of physical activity level were determined at baseline and at the end of the intervention period. RESULTS: Mean (SD) baseline systolic and diastolic blood pressures were 139 .9 (9.3) mm Hg and 76.0 (7.3) mm Hg, respectively. For systolic blood press ure, adjusted mean (SE) changes during the 12-week intervention period were -8.4 (1.6) mm Hg and -7.0 (1.6) mm Hg in the aerobic exercise and T'ai Chi groups, respectively teach within-group P < .001; between-group P = .56). For diastolic blood pressure, corresponding changes were -3.2 (1.0) mm Hg i n the aerobic exercise group and -2.4 (1.0) mm Hg in the T'ai Chi group tea ch within-group P < .001; between-group P = .54). Body weight did not chang e in either group. Estimated maximal aerobic capacity tended to increase in aerobic exercise (P = .06) but not in T'ai Chi (P = .24). CONCLUSIONS: Programs of moderate intensity aerobic exercise and light exer cise may have similar effects on blood pressure in previously sedentary old er individuals. If additional trials confirm these results, promoting light intensity activity could have substantial public health benefits as a mean s to reduce blood pressure in older aged persons.