What is the dose-response relationship between exercise training and blood pressure?
Most studies of exercise and blood pressure have used a standard exercise programme with a single level of physical activity. To determine the nature of the dose-response relationship however it is necessary to examine several levels of activity, preferably in the same subjects. We have recently performed several randomised crossover studies comparing different levels of regular exercise. The intensity and duration of exercise bouts were constant throughout the studies, but their frequency was varied. Standard bouts consisted of 30 min of bicycling at 60%-70% of maximum work capacity. The exercise was performed either three-weekly or 7-weekly in randomised order and each level was maintained for one month. In sedentary normal subjects three bouts of exercise/week for a total of 90 min lowered blood pressure by 10/7 mmHg. With seven bouts, i.e. a total of 210 min exercise/week, blood pressure was only slightly lower than 3-week exercise and was 12/7 mmHg below sedentary values. Response
