Will exercise help me lose weight?
Exercise alone is not very effective for dropping pounds, but it is one of the best ways to trim fat and stop middle-aged spread. Exercise combined with diet is better than diet alone for losing weight and keeping it off.24 To lose weight, you will need to get about 60 to 90 minutes of moderate exercise most days of the week in addition to counting calories.25 Don't be disheartened if the needle on the scale doesn't budge—exercise helps you lose fat, especially troublesome belly fat, even if you don't lose pounds.26, 27 This is because exercise builds muscle and muscle weighs more than fat.
On average, US adults gain 0.4 to 1.8 pounds a year and women tend to gain more weight over time than men.28, 29 Exercise helps prevent or stall age-related weight gain, especially if you are already overweight.30, 31 In a 10-year study of more than 15,000 adults, obese women who walked quickly for 75 to 100 minutes a week gained 9 pounds less than obese women who did not walk regularly.32 To prevent weight gain, you should get 60 minutes of moderate to vigorous exercise most days of the week and avoid consuming too many calories.
Does being active prevent diabetes?
Yes. Women who are more active are less likely to develop diabetes. The Women's Health Study followed more than 35,000 women age 45 and older for nearly 7 years.33 The most active women cut their risk of developing diabetes by 26% compared with the least active women. In this study, the most active women burned 1500 calories or more a week in various activities. It doesn't matter how you burn the calories: in another study of more than 70,000 nurses, walkers reduced their risk of diabetes just as much as vigorous exercisers.34 Lifestyle changes including diet and exercise also help prevent full-blown diabetes in men and women with early signs of blood sugar problems or prediabetes.35, 36
Does exercise help if I already have diabetes?
Yes. Aerobic exercise and resistance training (using weights or elastic bands) help women with diabetes keep blood sugar levels in check.37 Women with diabetes who are physically active (e.g., regular walkers) are also less likely to suffer heart problems including heart attack than sedentary women with diabetes.38
Will exercise improve my cholesterol levels?
Yes. Regular exercise improves cholesterol levels mostly by increasing HDL (good) cholesterol and lowering triglycerides—another type of blood fat that raises your risk for heart disease.1 In a review of 51 studies, HDL cholesterol increased an average of 4.6% in men and women after 12 weeks of aerobic exercise training (e.g., walking or jogging on a treadmill, or using an exercise bike).39 Exercise can also lower LDL (bad) and total cholesterol, but the effects vary from person to person and depend on how high your cholesterol levels are to begin with. Even if your total and LDL cholesterol levels don't drop, being active can stop them from getting worse. Exercise also helps change the size of the LDL cholesterol so it is less likely to clog up your arteries.40
Will being active lower my blood pressure?
An aerobic exercise training program (e.g., walking or jogging on a treadmill, or using an exercise bike) lowers blood pressure, especially in people who already have high blood pressure.41 Exercise also prevents high blood pressure from developing in the first place. Unfit men and women are up to 52% more likely to develop high blood pressure than very fit men and women.42
It is not clear whether low-intensity activities such as gardening help prevent or lower high blood pressure in women. In studies that track everyday physical activity levels, active men are less likely to develop high blood pressure than sedentary men, but this benefit has not been shown for active women.43, 44 This may be because women burn fewer calories in leisure time activities than men, and the activities women choose tend to be on the lighter side.
Does watching TV increase my risk of diabetes or obesity?
The more hours in the day you spend being sedentary (e.g., sitting at a desk, driving), the less time left for being active and burning calories. While you can't be the Energizer Bunny,® it's important to find time every day (even 10 minutes) to get moving. In the Nurses' Health Study, the risk of being obese or developing diabetes increased with every additional 2 hours per day spent watching TV.45 You burn fewer calories watching TV than with other types of sedentary behavior such as reading, writing, or driving.46 On top of that, TV viewing goes hand in hand with snacking. Time in front of the TV doesn't have to be sedentary. You can pedal a stationary bike or do light weights while watching your favorite shows, or even try an exercise video or DVD.
What other health benefit does exercise have?
Besides heart disease, exercise lowers your risk for certain cancers (particularly colon cancer).1 Weight-bearing exercise such as walking, aerobics, or lifting weights helps prevent osteoporosis or bone thinning by keeping your bones strong. Exercise can also help you cope with stress. Being active keeps you mobile and independent into old age,47 and it can ease the joint swelling and pain from arthritis.