Are you ready to kickbox your way to fitness? Amy Bento offers up five combos designed to tone and strengthen the upper and lower body with a rigorous calorie-burning workout. New to the sport? Don't fret. Bento breaks down all the complicated moves. You'll soon master spin back arms, spin back kicks, machine gun kicks, switch hops, slip hops, uppercuts and more. Also, sets of muscle-defining and toning intervals follow each combo.