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Air bike

Performing the: A Step-by-Step Tutorial Air bike

Place your hands behind your head, bending your knees and bringing them up so that your thighs are perpendicular to the ground.
Begin the exercise by extending your right leg out straight, while simultaneously bringing your left knee towards your chest and moving your right elbow to meet it.
Then, switch sides by extending your left leg out straight, bringing your right knee towards your chest, and moving your left elbow to meet it.
Continue to alternate between your right and left sides in a pedaling motion, as if you're riding a bicycle in the air, for your desired number of repetitions.