In studies that have compared physically active subjects with their sedentary counterparts, it has been found that those that are more active develop protective defenses against many chronic diseases including diabetes, heart disease and osteoporosis. Let’s take a closer look at the mechanisms involved.
Diabetes and exercise
Exercise is known to improve glucose control, i.e. muscle sensitivity to insulin, so that more glucose is taken up by muscles, less glucose is released from the liver and less insulin is produced by the pancreas. This has the effect of decreasing blood glucose levels, improving glucose control, and insulin response and insulin sensitivity.
Coronary Artery Disease (CAD) and exercise
Many studies have found an inverse relationship between physical activity and the development of CAD or “narrowing of the arteries” from the formation of cholesterol plaques. Regular physical activity improves fitness levels and decreases CAD risk by lowering blood pressure, slowing the rise in heart rate during exercise, along with lowering blood cholesterol and glucose levels. Exercise also leads to decreased blood clotting activity at rest, reduced red blood cell stickiness and increased insulin sensitivity.
Osteoporosis and exercise
Osteoporosis is characterised by low bone density (BD) and low bone mineral content (BMC), both of which are lost through the ageing process. In many studies physical activity (particularly weight bearing and strength training types) has been found to increase or maintain BD and BMC and thus prevent the development of osteoporosis.
