1. Physical activity helps you lose weight by burning calories, boosting resting metabolism, and buffering you from bone and muscle loss that can result if you diet alone.
2. High levels of physicial activity can decrease your risk of colon cancer by 40 to 50 percent.
3. Exercise helps you get better sleep. In one study, people who walked more than six blocks a day had one-third fewer insomnia problems than their less active cohorts.
4. Walking 30 minutes five days a week can increase your life span by one and half years. Make that running, and it may add up to four years. That's the conclusion of a 2005 study published in the
Archives of Internal Medicine, which showed that it's never too late to increase longevity.
5. Half-hour aerobic sessions three to five times a week have been shown to cut symptoms of mild to moderate depression nearly in half. One study suggests that exercise can be as effective as drugs in treating major depressive disorder.
6. Brisk walking for just an hour or two a week can reduce the risk of breast cancer in postmenopausal women by nearly 20 percent. And for those who already have the disease, walking three to five hours a week may reduce the chance of dying from it by as much as 50 percent.
7. Aerobic exercise, such as a half hour of rapid walking five days a week, has been shown to cut the risk of catching a cold nearly in half in postmenopausal women.
8. People who work out have more energy than nonexercisers, according to researchers at the University of Georgia, based on a review of 70 studies. That boost, on average beats the effect of stimulant drugs.
9. Working out - resistance training in particular - helps maintain, and even modestly increase, bone density to reduce the risk of osteoporosis.
10. An active lifestyle halves the risk of developing heart disease. Walking up to 12 miles a week (translation: 30 to 50 minutes a day) significantly improves heart health, according to a Duke University study. And if you're at high risk for diabetes, working out only about 20 minutes a day, combined with a low-fat diet, can reduce the chance of developing the disease by 58 percent.
11. Just working out 15 minutes three days a week may reduce the risk of developing dementia and Alzheimer's disease by 30 to 40 percent, according to a study last year in the
Annals of Internal Medicine. For healthy older adults, a six-month program of exercise can reverse the age-related loss of brain tissue that begins around age 40 by two to three years, especially in regions responsible for memory and higher cognition.
12. Working out improves your sex life - by not only enhancing self-esteem but also strengthening the cardiovascular system. One study found that women who cycled vigorously for 20 minutes before watching an erotic film had significantly greater vaginal response compared with when they were inactive.