Why: Similar to Knee-to-Elbow Planks, but increases the oblique challenge.
How: Assume a push-up position with your body in a straight line. Kick your right leg under your body to your left side. Keep your leg straight and your foot in the air. Extend your leg behind your body to return to the starting position. Repeat on the opposite side and continue in alternating fashion for the specified number of reps.
Sets/Reps: 2×5 each side
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