Why: Lifting an arm off the ground forces your core to stabilize to maintain balance and control.
How: Assume a push-up position with your body in a straight line. Touch your right hand to your left shoulder. Return your right hand to the ground to resume the starting position. Repeat with your left hand and continue in alternating fashion for the specified number of reps.
Sets/Reps: 2×5 each side
Tip: Walk your hands forward (as shown) to increase the difficulty.
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