Exercise in the prevention of stroke.

Lifestyle and behaviour modifications that include exercise are effective in the prevention of cardiovascular disease and stroke. The benefits are manifested largely through the role that exercise plays in the control of certain modifiable risk factors, such as control blood lipid abnormalities, diabetes and obesity. Exercise also adds an independent effect in the lowering of blood pressure in certain hypertensive groups, thus favourably modifying a major risk factor for stroke. The Honolulu Heart Program, a 22 year follow-up of 5,362 men (aged 58 to 68) revealed that physical activity was protective against "clot caused" stroke only in nonsmokers. This study also revealed that inactive and partially active men compared with those who were active had fourfold increases in intracerebral hemorrhage and threefold increases in subarachnoid hemorrhage. The Framingham study suggested a relationship between sedentary work and stroke although this was not statistically significant. In a 16-year follow-up of 3,263 cargo handlers the death rate from stroke was similar to that of more sedentary people. However, the mortality was threefold higher among those who were sedentary and had higher systolic blood pressure. The exercise employed in prevention can be mild to moderate in intensity and may be of the type experienced in occupational, recreational and leisure time activity. Clinical data reveal that aerobic exercise equal to or greater than 50% of one's maximum capacity can be "protective" in cardiovascular disease.