Moderate- and high-intensity exercise lowers blood pressure in normotensive subjects 60 to 79 years of age

To investigate the effects of exercise intensity on resting blood pressure (BP) in normotensive elderly subjects, 44 sedentary healthy subjects aged 60 to 79 years of age were studied during 6 months of walking exercise. Subjects were ranked according to maximal oxygen consumption and randomly stratified to groups that trained at 70% (n = 19) or 80% to 85% (n = 14) of maximal heart rate reserve, or to a control group (n = 11) that did not train. Initial BP was established during a 2- to 3-week control period. During the first 3 months, both exercise groups progressed to 70% of heart rate reserve for 40 minutes 3 times each week. The moderate-intensity group continued to train at 70% (45-minute duration) for an additional 3 months, the high-intensity group progressed to training at 85% of heart rate reserve (35-minute duration). Maximal oxygen consumption increased (p [less than or equal to] 0.05) during the initial 3 months in both exercise groups (25.2 to 28.1 ml.[kg.sup.-1].[min.sup.-1] and 26.3 to 29.3 ml.[kg.sup.-1].[min.sup.-1]) and continued to increase (p [less than or equal to] 0.05) after 3 additional months of training, but the increase was greater (p [less than or equal to] 0.05) in the high-intensity group (28.1 to 29.4 ml-[kg.sup.-1]-[min.sup.-1] and 29.3 to 32.8 ml.[kg.sup.-1].[min.sup.-1]). Systolic BP decreased (p [less than or equal to] 0.05) similarly at 6 months in both training groups (120 to 111 mm Hg and 120 to 112 mm Hg). Diastolic BP also decreased (p [less than or equal to] 0.05) similarly at 6 months in both training groups (72 to 64 mm Hg and 75 to 68 mm Hg). Resting heart rate decreased (p [less than or equal to] 0.05) to the same magnitude at 6 months in both training groups (71 to 66 bents/min and 69 to 63 beats/min). Body weight did not change in any group (p [less than or equal to] 0.05). The sum of 7 skinfold fat measures decreased (p [less than or equal to] 0.05) similarly at 6 months in both training groups (175 to 164 mm and 173 to 159 mm). Our data indicate that walking exercise between 70% and 85% of heart rate reserve lowers resting BP in normatensive elderly subjects, and produces a moderately favorable conditioning benefit similar to that observed in younger persons.