Tracy Anderson, the pint-sized trainer behind the Metamorphosis DVDs and leg sculptor to Gwyneth Paltrow and
Jennifer Lopez, recommends the all-fours knee tuck and back kick for lean legs. (You never know when you might expose pose some side butt.) From your hands and knees, tuck one leg in parallel to the chest, lift it open to the side and then extend it straight
back behind ind the body. Repeat 30 times on each side.