If you play tennis, baseball or golf, then here's a fitness challenge for you. "This fast-paced, three-move circuit works your entire core, but really blasts your oblique muscles," says Todd Durkin, C.S.C.S., author of The IMPACT! Body Plan. Your obliques -- the abs muscles on the sides of your torso -- work together with the muscles in your lower back and hips so you can rotate your body with more power. The stronger your obliques, the more explosively you can swing and throw. Ready to put your rotational power to the test? Watch the video to see how to perform the challenge.

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How to do it: Grab a stopwatch. Perform the three exercises back-to-back, moving from one exercise to the next without rest. That's one round. Repeat.

Russian Twist
Sit holding a dumbbell vertically in front of your chest. Lean your torso back slightly and raise your feet off the floor. Now rotate the weight to your left and then to your right. Move back and forth quickly. Do 20.

Groiner
Get into a pushup position. Jump your feet forward to the outside of your hands (or as close as you can). Pause for a brief second, and then jump your feet back to the starting position. That’s 1 rep. Do 10. (The greatest exercise of all time just got better. Click here to learn The Pushup That Blasts Your Core.)

Bicycle Oblique Crunch
Lie face up with your hips and knees bent 90 degrees so that your lower legs are parallel to the floor. Place your hands behind your head and keep your elbows flared outward. Lift your shoulders off the floor, and trust your upper body to the right as you pull your right knee in as fast as you can until it touches your left arm. Simultaneously straighten your left leg. Return to the starting position and repeat to the right. Do 50. (Which moves do fitness experts hate? Read 5 Exercises That Make Trainers Cringe.)

How do you compare? Durkin completed two rounds of the challenge in two minutes and fifty-four seconds. Tell us your time in the comments below.