A new US study has reported that a half-hour daily dose of moderate exercise, such as walking, may be more effective than rigorous exercise to protect against cardiovascular disease and diabetes.

Lead author and exercise physiologist Cris Slentz, of Duke University Medical Centre, reported, ‘On the surface, it seems to make sense that the harder we exercise, the better off we’ll be, and by some measures that’s true. But our studies show that a modest amount of moderately intense exercise is the best way to significantly lower the level of a key blood marker linked to higher risk of heart disease and diabetes. More intense exercise doesn’t seem to do that.’

For a six-month period, study participants were placed into one of four exercise groups: high amount/high intensity; low amount/high intensity; low amount/moderate intensity; or a non-exercising control group.

No amount of physical activity was found to significantly alter levels of low-density lipoprotein (‘bad’ cholesterol), but the length and intensity of exercise positively affected levels of high-density lipoprotein (‘good’ cholesterol). Some of the benefits of moderate exercise also appeared to last considerably longer than those gained through intense training.

Low amount/moderate intensity exercise was also found to significantly lower levels of triglycerides, a good indicator of insulin resistance and a marker for diabetes. Lower triglyceride levels equate to a lower risk of heart disease and diabetes. ‘A proper exercise program appears to be able to lower a person’s insulin resistance in just a matter of days. We were also amazed to see that the lower triglyceride levels stayed low even two weeks after the workouts ended,’ commented cardiologist Dr William Kraus.