5 common fitness myths

1. Exercise is a waste of time unless you work out hard and often. A study by the National Institutes of Health found that moderate physical activity works just as well as intense exercise for losing weight. Walking, bicycling and swimming are all good ways to exercise at a modest pace. Walking for as little as an hour a week can lower the risk of heart disease.

2. Yoga is a completely gentle and safe workout. Some forms of yoga are physically and mentally difficult. Although injuries are rare, staying in certain positions can cause nerve damage or back pain. As with any exercise, proper instruction is necessary for a safe workout. If you have a health condition, talk with your doctor before you try yoga.

3. You can lose all the weight you want just by exercising. Increasing physical activity is just one part of a successful weight-loss plan. Most people also need to cut calories. How many pounds you lose may also depend on your genes. What works for one person may not work for another. Exercise, though, is an important component of just about any weight loss program - and it offers many other health benefits.

4. Water-fitness programs are mainly for older adults or people with injuries. Research has shown that exercising in water can be a challenging and effective way to get fit and lose weight. It's good for just about anyone.

5. If you want to lose weight, don't strength-train. It will make you "bulk up." Experts recommend both cardiovascular and strength training exercises to maintain a healthy weight. The more muscle you have, the more calories you burn - even when you're not working out. As a rule, lifting heavier weights fewer times during a workout will make you stronger - and build larger muscles. Doing more repetitions with lighter weights will improve your muscular endurance. A fitness professional can help you create a strength-training routine that works for you.