Diseases such as heart disease, breast cancer and diabetes have been shown to decrease in risk with regular exercise. Heart disease risk can be lowered by the increase in good cholesterol and decrease in bad cholesterol that exercise facilitates. Breast cancer is a risk that could possibly be lowered as another health benefit. Exercise lowers estrogen levels. High estrogen levels have been linked scientifically to breast cancer.
Exercise also lowers insulin resistance which can lead to diabetes.
Along with these health benefits, exercise also increases self-esteem. The self-esteem improvement usually helps people to stick to their program. Exercise can help prevent weight gain because exercisers expend more energy so they can eat more without gaining weight. Also, exercise increases physical reserves so the body can withstand minor problems and heal itself more readily. Other benefits can be a better night's sleep, increase in bone density over time and better balance.