Exercise Myth 01:
"Muscle weighs more than fat."

No, it doesn't. But we know what you mean
This myth looks like it tried to tell the truth, but garbled it. Put a pound of muscle on one scale, a pound of fat on the other—the scales balance exactly. There's no difference in weight. BUT… you might need a bigger scale pan for the fat. The difference is size. Muscle doesn't need all that room. Muscle is much denser tissue than fat—so the pound of muscle you add with your strength training will take up much less room in your body than the pound of fat you burned off with your cardio.

According to research…
The average woman who strength trains two to three times a week for eight weeks gains 1.75 lbs. of lean weight and loses 3.5 lbs. of fat. Nice! A net weight loss of 1.75 lbs.—and twice the number of bigger, fatty pounds gone. For a visual of the arithmetic, picture 3.5 lbs of lard stacked next to a 1.75 lb. filet.

Muscles burn calories
Muscle burns calories, so the more muscle you have, the more calories you burn—making it easier to burn fat and harder to gain it! Muscle tissue is significantly more vascular than body fat, meaning it has much better blood supply than fat does, and burns more calories at rest.