Blood pressure is lower on days when a person is physically active compared to when the individual is not. Someone who is very inactive has six times the risk of heart disease as someone who is active. The amount of physical activity needed to reduce cholesterol is not very much, the studies show. Physical activity also benefits the blood-clotting system, reducing the body s ability to produce dangerous blood clots that can obstruct blood vessels to the heart, thereby causing a heart attack or stroke. After three months of physical activity by middle-aged, overweight men with mildly elevated blood pressure, one study reported that platelet aggregation was reduced by 52 percent, compared to 17 percent with a control group.
Platelets play a role in blood clot formation.
A reduction in platelet aggregation leads to a reduced risk of blood clots that can trigger heart attacks and strokes. Another benefit is found in the endothelial cells that line blood vessels feeding the heart and brain. Physical activity improves their ability to produce nitric oxide, a substance that causes the blood vessels to relax and contract more efficiently. Physical training affects both healthy people as well as those with heart disease. After starting an exercise program, moderate physical activity three to five times a week will improve cardiovascular function in eight to 10 weeks as well as improve risk factors for cardiovascular disease and stroke.