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-intensity 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 > or = 60 years) with systolic blood pressure 130-159 mm Hg and diastolic blood pressure < 95 mm Hg (not on antihypertensive medication). INTERVENTION: Participants were randomized to a 12-week aerobic exercise program 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 pressure, 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 (each within-group P < .001; between-group P = .56). For diastolic blood pressure, corresponding changes were -3.2 (1.0) mm Hg in the aerobic exercise group and -2.4 (1.0) mm Hg in the T'ai Chi group (each within-group P < .001; between-group P = .54). Body weight did not change 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 exercise may have similar effects on blood pressure in previously sedentary older individuals. If additional trials confirm these results, promoting light intensity activity could have substantial public health benefits as a means to reduce blood pressure in older aged persons.