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Straight-arm jacknife
Begin in a straight-arm plank position with your hands shoulder-width apart. Cross your right leg underneath the body, keeping your arms straight, and drop the right hip as close to the floor as possible, then lift the hips up into a pike position (a downward dog pose, but with one leg crossed under the other). Focus on bringing the last rib on your right side to your right hip bone. Perform 20 reps on each side and repeat the cycle one more time.
Why it�s good for your sex life This exercise trains the internal and external obliques, which allow the body to bend laterally and twist, which comes in handy when changing up positions in the sack.
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