COLUMBIA, Mo. – Cardiovascular disease is the leading cause of death in the United States. The amount of stress and anxiety a person experiences is a major factor in cardiovascular disease. For the past three decades experts have vacillated in their recommendations concerning the amount and intensity of exercise required to alleviate stress and anxiety.

Recently, most experts have agreed that a moderate to low amount of regular exercise can ease personal tension and stress. However, a new study by researchers at the University of Missouri-Columbia shows that a relatively high-intensity exercise is superior in reducing stress and anxiety that may lead to heart disease. Moreover, the researchers found that high-intensity exercise especially benefits women.

“Conventional wisdom says that exercising for 30 minutes at a moderate exercise intensity is more effective in reducing anxiety than either a low or high intensity dose,” said Richard Cox, professor of educational and counseling psychology and leader of the study. “This conclusion, however, is deceptively simple because reductions in anxiety are not always observed immediately following a high intensity bout of exercise.”

In the study, female participants, ages 18 to 20 and 35 to 45, completed three experimental sessions. Each session started with a test to determine the anxiety level of the participant. Following the test, the women either did not exercise (control condition) or exercised at a moderate or high-intensity level for 33 minutes. After the session, Cox measured anxiety levels at 5, 30, 60 and 90 minutes post-exercise.

Although all three exercise conditions, including the control condition, showed a decline in anxiety over time, Cox found the high-intensity level experienced the sharpest decline. Cox said the intensity of exercise conditions did not differ in anxiety levels at baseline or immediately after exercise, but a difference favoring the high intensity level emerged at 30, 60 and 90 minutes post-exercise.

Results also showed that when the iron status of the women was taken into consideration, the beneficial effect of high-intensity exercise was greater for the older women.

“This is a relationship that needs to be further explored,” Cox said. “It appears to suggest that after controlling for iron status, the beneficial effects of exercise on anxiety may only apply to older women and not to younger women.”

Cox believes this study, which is scheduled for publication in the Research Quarterly for Exercise and Sport, will prove beneficial to medical practitioners in the fight against heart disease.