CARDIOVASCULAR BENEFITS OF IMPROVED EXERCISE CAPACITY

The evidence suggesting that regular exercise can help to prevent coro nary artery disease is overwhelming. While some studies have suggested that exercise will not provide health benefits, our inactive populati on needs to pay heed to the substantial data presented by the many int ernational health organisations suggesting the opposite. The American Heart Association Medical/Scientific Statement on Exercise emphasised the large role regular aerobic physical activity plays in the preventi on of cardiovascular disease. Several human studies have also demonstr ated the positive effects of long term exercise on the human heart. Fo r example, it has been shown that a consistent exercise programme can lessen the impact of atherosclerotic plaques through increasing corona ry artery diameter. Echocardiography studies on a training group of co mpetitive swimmers have shown that exercise training can induce rapid changes in left ventricular dimensions and mass, which can ultimately lead to an increased stroke volume and increased maximal oxygen consum ption. Studies on sedentary individuals have also demonstrated an incr ease in maximal oxygen uptake with a regular endurance exercise progra mme. In addition to these health benefits, habitual dynamic exercise c an also decrease the likelihood of a cardiac event. Others have demons trated a 50% lower incidence of coronary events in those individuals m aintaining rigorous activity 2 days a week. With the preponderance of evidence revealing the health benefits of habitual exercise, it is str iking to learn that more than 50% of the US population exercises for l ess than 20 minutes, 3 days a week. The widespread nature of this sede ntary lifestyle makes inactivity an attributable fraction of the total risk factors associated with cardiac disease. The amount of exercise needed to reduce the risk of coronary artery disease is a minimum aero bic workout of 30 minutes, 4 to 5 times a week, such as a vigorous wal k. Comprehensive programmes promoting exercise training should be impl emented at a level appropriate to an individual's capacity and need.