Fast Workouts That Really Work!

By Lucy Danziger, SELF Editor-in-Chief

I love my long training runs, but most days carving out more than an hour to work out just isn't in the cards. And when my schedule is really crammed, shoehorning a sweat session seems next to impossible.

Luckily, the fantastic fitness team at SELF let me in on a little secret: You can get an hour's worth of fitness and calorie burning in 20 short minutes. Yes, I was skeptical at first, but this fat-blasting routine is as ultraeffective as it is speedy, and the secret lies in high-intensity spurts of energy. Here's how to do it:

• Pick any cardio you like (running, swimming, the elliptical trainer). Warm up for 2 minutes at a moderate pace, then sprint for 30 seconds at the highest intensity you can muster. Slow down and do 90 seconds at a catch-your-breath recovery pace. Repeat eight times. You'll torch more calories in less time, while you burn fat faster. Follow this cardio session with a few of the following fast firmers for a total-body workout in less than 30 minutes.

• Tighten your tummy: Do two sets of 10 to 12 crunches on a stability ball. Research from the University of Auckland, Tamaki Campus, in New Zealand, revealed that using the ball makes crunches 20 percent more effective compared to hitting the floor.

• Firm up legs: Stand on left foot, hands on hips, and bring right knee to hip level in front. Trace a horizontal figure eight in front of you with knee. Then bend left knee and hop to right, landing on right foot. Repeat figure eight with left knee, then hop back to left to complete one rep. Do 10 reps, then hop back and forth 10 times to complete one set.

• Boost your bottom: Stand with feet hip-width apart, hands on waist. Shift weight to left foot and lift heel of right foot so you're resting on toes. Bend left knee and sink hips back, keeping weight off right foot (toes stay on ground). Rise up. Do 12 reps on left leg, then switch legs and repeat.

• Bare amazing arms: Holding a dumbbell in each hand, stand with feet hip-width apart. Raise arms, palms down, out and slightly forward to shoulder height. Slowly lower them behind you so weights almost touch. Do 12 reps.

• Slim all over: Stand with feet hip-width apart. Keeping legs as straight as possible, bend forward and walk hands out until they're under shoulders. Do two push-ups, then walk hands back and stand. Repeat twice, doing four push-ups, then six.