This move helps burn more calories while you work the power (fast-twitch) muscle fibers in your legs—a killer combo for trimmer thighs.
How to do it: Start standing with your right foot forward, left leg back and lower into a runner's lunge, reaching your left arm towards your right foot and extending your right arm behind you [A]. Push off the floor with both feet, jumping straight up, scissoring legs midair, and land back into a runner's lunge with your left leg forward, right arm reaching across. If an injury prevents you from jumping, try quickly alternating your legs with a rear tap instead of the jump. Do 15 switches (or alternating rear taps) total.
Quick Form Tip: Start slow to insure proper form on your landing (always keep your knees behind your toes on the front leg of your lunge). Progress into a faster speed when you're ready to advance.