Hypertension is common, and even slight elevations in blood pressure can be associated with health risks. Regular aerobic exercise helps prevent hypertension. In patients who already have hypertension, such exercise has been shown to lower systolic and diastolic blood pressure by a mean of 10 mm Hg. For mild or labile hypertension, lifestyle modification that includes at least a half hour of moderate aerobic exercise at least 3 days a week should be tried before using drug therapy. If medication is needed, one that is not likely to impede the patient's ability to exercise should be considered.