Physical effort, for example, increased people's chance of having a heart attack, whether they were generally sedentary or exercised on a regular basis. Nonetheless, the researchers stated that people experience "external stressors" such as anger and exercise on a daily basis without succumbing to a heart attack. They concluded that other factors are likely responsible for causing heart disease. In addition to external stressors, physical exertion also causes internal stress. As we exercise, our hearts work harder to deliver blood to working muscles. This increased demand on the heart leads to fatigue, especially in individuals who may not be used to strenuous activity. Repeated episodes of cardiac fatigue can result in damage to the heart muscle, which can lead to heart failure. Studies have shown that people who walk regularly experience less risk of heart disease than those who do not walk at all. Even more impressive is the fact that those who exercise vigorously every week are still protected by this association. It appears that the more you exercise, the better it is for your heart health. Exercise is important for maintaining good health. It reduces your risk of developing diseases such as diabetes, high blood pressure, and obesity. Exercise also helps keep your weight under control by using up stored energy in your body through sweat. A reduced need for storing energy along with decreased abdominal fat means you're burning calories at a faster rate.