Want to save time at the gym? Try our multitasking move of the week demonstrated by Alison Sweeney, host of The Biggest Loser. Bicycle Abs With Pec Fly works your front deltoids, chest, and core muscles all at once.

Here's how to do it: Lie faceup on the floor with a dumbbell in each hand and raise your arms straight overhead. Bend your left knee and draw it in to your chest, while lifting your right leg 2 to 3 inches off the floor. With your abs engaged and the small of your back pressed into floor, bicycle your legs while lowering your arms out to sides. Be sure to keep a slight bend in your elbows. Return to start. Continue for 30 seconds, working up to 1 minute.

Tip: Protect your spine! Your legs should be low enough to challenge your abs, but not so low that you're stressing your back.

Try this move: Bicycle Abs With Pec Fly