Hypertension is present in epidemic proportions in adults of industrialized societies and is associated with a markedly increased risk of developing numerous cardiovascular pathologies. There is a continuing debate as to the efficacy of aggressive pharmacological therapy in individuals with mild to moderate elevations in blood pressure. This has led to a search for nonpharmacological therapies, such as exercise training, for these individuals. The available evidence indicates that endurance exercise training by individuals at high risk for developing hypertension will reduce the rise in blood pressure that occurs with time. Thus, it is the position of the American College of Sports Medicine that endurance exercise training is recommended as a nonpharmacological strategy to reduce the incidence of hypertension in susceptible individuals. A large number of studies indicate that endurance exercise training will elicit a 10 mm Hg average reduction in both systolic and diastolic blood pressures in individuals with mild essential hypertension (blood pressures 140-180/90-105 mm Hg). Endurance exercise training also has the capacity to improve other risk factors for cardiovascular disease in hypertensive individuals. Endurance exercise training appears to elicit even greater reductions in blood pressure in patients with secondary hypertension due to renal dysfunction. The mode (large muscle activities), frequency (3-5 d.wk-1), duration (20-60 min), and intensity (50-85% of maximal oxygen uptake) of the exercise recommended to achieve this effect are generally the same as those prescribed for developing and maintaining cardiovascular fitness in healthy adults. Exercise training at somewhat lower intensities (40-70% VO2max) appears to lower blood pressure as much, or more, than exercise at higher intensities, which may be important in specific hypertensive populations. Physically active and fit individuals with hypertension have markedly lower rates of mortality than sedentary, unfit hypertensive individuals. Thus, it seems reasonable to recommend exercise as the initial treatment strategy for individuals with mild to moderate essential hypertension. A follow-up period should assess the efficacy of the patient's exercise program, and adjunct therapies should be implemented according to the individual patient's blood pressure and CAD risk factor goals. Individuals with more marked elevations in blood pressure (> 180/105 mm Hg) should add endurance exercise training to their treatment regimen only after initiating pharmacologic therapy. Resistive, or strength, exercise training is not recommended to lower blood pressure in individuals with hypertension when done as their only form of exercise training.(ABSTRACT TRUNCATED AT 400 WORDS)