A sedentary lifestyle could be a risk for high blood pressure (hypertension), according to the results of both cross sectional and longitudinal studies.

High blood pressure is present in epidemic proportion and is associated with a markedly increased risk of developing numerous cardiovascular complications. All current treatment guidelines emphasize the role of non-pharmacological interventions, physical activity included, in the treatment of mild to moderate high blood pressure.

A large number of studies have demonstrated that regular exercise reduces the incidence of high blood pressure. In addition to preventing high blood pressure, regular exercise has been found to lower blood pressure (10 mmHg average reduction in both systolic and diastolic pressure), improve lipoprotein-lipid profiles and insulin sensitivity.

As part of the initial treatment, exercise is recommended for 12 months in patients with stage 1 hypertension, with no other coronary risk factors and no evidence of cardiovascular disease, and for as long as 6 months in those with other risk factor, but not diabetes.

Dynamic exercise of moderate intensity (e.g. brisk walking, cycling) for 50-60 minutes, 3-5 times per week, is preferable to vigorous exercise because it appears to be more effective in lowering blood pressure. In addition to reducing high blood pressure, physical activity improves other cardiovascular risk factors.

In previously sedentary subjects with high blood pressure, it was found that clinically significant decreases in blood pressure can be achieved with relatively modest increases in physical activity above sedentary levels and that the volume of exercise required to reduce blood pressure may be relatively small.

In a study of 25 adults with high blood pressure, it was concluded that four 10-minute bouts of brisk walking were as effective as 40 minutes of continuous brisk walking per day at reducing blood pressure.

The underlying mechanism of action of exercise on blood pressure seems to be multifactorial involving a decrease in pressor factors such as plasma norepinephrine, the serum Na/K ratio, endogenous ouabain-like substance and erythrocyte mean corpuscular volume, as well as an increase in depressor factors such as plasma prostaglandin E, serum taurine and urinary dopamine excretion.
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