1. It reduces your risk of the common cold. A consistent, medium-intensity routine is a proven cold-stopper. Taking a brisk, 40-minute walk 4 days a week, for example, can cut the number of colds you experience by 25 to 50 percent and can make the colds you do catch shorter by half, studies show. Moderate exercise boosts the number and activity level of important immune-system players called natural killer cells.
3. It helps prevent and treat Osteoporosis. Though brisk walking will help, it may not be sufficient. The impact as your feet hit the ground stimulates cells in the bones of your legs, hips, and spine to build new bone, preventing the thinning that can lead to osteoporosis. But higher-impact activities such as dancing, hiking, jogging, jumping rope, climbing stairs, or playing tennis do more to stimulate bone growth and maintain bone density. (Check with your doctor first if your bones are already thinning or if you have joint problems or are prone to falls.)
Strength-training is also important. It stimulates bone growth when muscles and ligaments “tug” on bones as you lift weights, use resistance bands or machines, or do exercises (think push-ups) that rely on your own body weight to build muscle. Your best bet is a combination of high-impact exercise and strength-training; in one study, this strategy preserved bone mineral density in women who had just reached menopause, a time when loss of bone density accelerates.
4. It reduces chronic pain. At least 10 minutes of aerobic exercise — biking, fast walking, running on the treadmill — can significantly improve chronic pain, likely by releasing natural pain relievers called endorphins.
5. It battles chronic fatigue syndrome. A workout may leave you exhausted, but you’ll probably feel better in the long run. British researchers asked a group of chronic fatigue syndrome patients to walk or perform some other aerobic exercise at least 5 days a week, increasing their daily activity to a maximum of 30 minutes. After 3 months, these patients were twice as likely as others who took flexibility or relaxation classes to say that their symptoms had improved and that they felt better. A year later, three-quarters of the exercisers had resumed normal daily activities, and some had returned to work.
6. It can help prevent colon cancer. Getting regular exercise can lower your risk by up to 25 percent; a half-hour walk, four times a week, is all it takes. And if you’re a regular meat-eater, cutting back on red meats and processed meats such as hot dogs, sausage, and lunch meats can also help. Experts at the National Cancer Institute estimate that people who eat red meat or processed meats twice a day most days increase their cancer risk by 24 percent; eating it once a day raises risk by about 20 percent above normal.
7. It prevents and relives constipation. A way to get things moving is to get yourself moving. Exercise can reduce straining and speed the passage of food through your digestive system. For some people, it cuts the odds of becoming constipated by about 40 percent.
8. It can battle diabetes. It depends where you are in the course of your disease. At first, eating a healthy diet, getting regular exercise, and losing weight can be quite effective at battling insulin resistance, the metabolic “glitch” behind type 2 diabetes. Insulin tells cells to absorb blood sugar. Staying sensitive to insulin can help delay your need for medication or allow you to use smaller doses.
In one study, people with type 2 diabetes who lost a significant amount of weight — an average of 24 pounds — within 1½ years after their diagnoses were twice as likely to bring their blood sugar levels under control as those who did not. Food choices matter, too. In a recent Italian study of people with type 2 diabetes, 56 percent of those who followed a traditional Mediterranean diet (think fish, olive oil, whole grains, nuts, and vegetables) were still medication-free after 4 years compared to just 30 percent of those on a low-fat diet with the same number of calories. The “good” fats from the Mediterranean diet seem to nurture insulin sensitivity, the researchers say.
9. It can help treat Parkinson’s Disease. Playing your kids’ or grandkids’ Wii — the Nintendo video game system in which the users move around as if actually playing various sports — could improve some symptoms of Parkinson’s disease. In one study, 20 people with the disease played Wii tennis, bowling, and boxing an hour a day, 3 days a week for 4 weeks. After the 4 weeks, the participants moved more easily, their fine motor skills improved, and they had more energy. Scores on a depression test also dropped to zero. The benefit may come from increased levels of dopamine released during exercise and while playing video games. Dopamine is the chemical lacking in the brains of people with Parkinson’s.
10. It can prevent strokes. Increase your heart rate. Just 30 minutes a day of exercise strenuous enough to get your heart beating faster can reduce your risk of stroke 20 percent. Exercise harder and watch the risk drop another 7 percent. (Check with your doctor about what amount of exercise is right for you.)