Welcome to the Get Fit Guys' quick and dirty tips to slim down and shape up.

My name is Ben Greenfield, and I'm the Get Fit Guy.

Just admit it, it would be pretty nice if you could walk into a gym and do a workout that burns fat and builds muscle at the same time.

There's nothing like the best of both worlds.

But is it really possible to lose that extra flab around your waistline and get firm toned muscles

at the same time? And if so, how do you do it without defying the laws of physics? In this episode,

you'll learn whether it is possible to lose fat and gain muscle at the same time,

and if so, how?

Technically, it seems impossible to build muscle and lose fat.

And here's why.

Your body needs about 2,500 calories to build one pound of muscle.

So, if you wanted to make one pound of muscle in seven days, you could eat an extra 350 calories

every day. Assuming your weight training, those extra calories can easily be converted into muscle.

But you also need to burn about 3,500 calories to lose one pound of fat. So if you wanted to

lose one pound of fat in seven days, each day you would need to

eat 500 fewer calories than you were burning, so that your body would use your storage

fat for energy instead of the calories that you're eating. Unless you have a very cool physics-defying

trick up your sleeve, it's impossible to eat an extra 350 calories a day to build muscle

and also eat 500 fewer calories a day to lose fat.

So at first glance, it should be impossible to both build muscle and lose fat.

But in a situation like this, the best place to turn is science,

which can tell us whether

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