Absolutely not. Lifting weights will not only help you lose weight, but maintain the loss. Here's why:
Muscle keeps your metabolism revved up, burning calories, fat, and glucose (sugar).
When you lose weight, up to 25% of the loss may come from muscle, resulting in a slower metabolism. Weight lifting will help preserve or rebuild any muscle you lose by dieting.
Muscle helps you with aerobic exercise. The stronger you are, the better you will be at any aerobic activity.
Weight training improves your body's muscle-to-fat ratio (you end up with less body fat and more muscle), which improves both your health and your fitness level.
Gaining muscle will help you look better as you define and tone your physique.
Building strength helps you feel good about yourself. Although the scale may show a slight weight gain when you start lifting weights (usually five pounds or less), you probably won't look heavier because the gain is in muscle, and your clothes may even fit more loosely.
Strength training, along with cardiovascular exercise, can boost your metabolism and can help you expend calories to lose weight. Strength training, however, also has the added benefit of helping you to preserve muscle as well. If you lose weight while only doing cardiovascular exercise, some of the weight loss may come from body fat as well as muscle. You want to preserve muscle because it can help to keep your metabolism elevated, since muscle burns calories at a higher rate than fat. Strength training can also help to promote a more “toned” appearance, which would be another added benefit to you as well.
The Surgeon General recommends that you strength train all major muscle groups two or more days per week. Consult your doctor before starting an exercise routine.
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