Look at an advertisement for the P90X workout. It’s obvious not only from the advertisements but also from the summaries of the workout that you’ll be gaining muscle. We’ve mentioned before that, if you’re doing a workout like the P90X that focuses on creating and toning muscle through using tools like the P90X Powerstands, you may not want to set a goal about how many pounds you may lose and instead set a goal that’s about a clothing size. This advice is because the rumors that you hear are true. Muscle does weigh more than fat does. The question is this: Exactly how much more does muscle weigh than fat?
Firstly, while we just said that it’s true that muscle weighs more than fat, that’s not exactly true. What is true is that muscle is more dense than fat is, so the same amount of muscle that takes up the same amount of space actually carries more weight in it. In our books, that’s the same as muscle weighing more than fat. The metaphor would be that a bag full of feathers (fat) weighs less than the same size bag full of bricks (muscle), but both take up the same amount of space.
Now that that’s out of the way, it’s time for a complicated formula! And you’ll need to get out your metric converters too, because this formula is only done in grams and milliliters. Muscle density is 1.06 grams per milliliter. Fat density is .9 grams per milliliter. That math means that tone liter of muscle would weigh 1.06 kilograms and one liter of fat would weigh less at .9 kilograms.
But you don’t really need to know the math. What you need to know is that what that sums up to is that you will weigh more with more of your body mass being dedicated to muscle. Because of that, you really should not set your body goals by pound when you start an exercise program. Of course, we think you should set your goals just by how good you feel, but if you want to focus on getting trimmer consider setting your goals by clothing size or inches reduced from parts of your body.
In the Slim in 6 workouts, Debbie Siebers does a great job of explaining toning and weight loss and the difference between muscle and fat. We think we did a pretty good job of explaining it here, too!