so that both legs are crossed. Untwine only to reverse the position of the legs. Keep repeating this scissoring action, with your lower abs contracted, about 8 to 10 times in the beginning. Increase it to 15 to 20 reps as you get stronger.Proshred Elite   Double Leg Lifts Lie down on your back with your hands placed under your butt and palms facing the floor. Then, contracting your lower abdominal muscles, and tightening the muscles of your legs, lift them straight up vertically, 

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