Total-Body, No-Equipment Workout

No space, no money to invest in a home gym, and no time? No excuses! Work your entire body with the following circuit workout. You don't need a lot of space to do it; all you need is your living room or bedroom floor. And while it tones all your muscle groups, it doesn't take a lot of time: repeat this circuit twice, and you'll still be done in about 20 minutes!