Hagberg said the exercise does not have to be vigorous. Walking or light jogging for a half hour several times a week may be enough to do the trick. And the drop comes pretty quickly, usually within a month, he said. There are several theories about how exercise lowers blood pressure. One mechanism is its role in increasing production of nitric oxide in the endothelium, the protective layer of cells that lines the inside of arteries.
Nitric oxide helps dilate blood vessels, which in turn lowers blood pressure.
It is estimated that 50 million Americans have high blood pressure, one of the primary causes of heart attacks and strokes. Exercise not only helps lower blood pressure, but it also helps control body weight, cholesterol and diabetes, all of which are risk factors for cardiovascular disease. Eating a healthy diet also can help reduce blood pressure. People who follow those guidelines can expect to see about a 10-point drop in their blood pressure, Hagberg said. Medication can lower blood pressure considerably more than exercise or diet, but many of the people with high blood pressure only have mildly elevated hypertension.