Work your butt, legs, and core with this reverse lunge and twist PLUS 4 more lower body exercises here: www.womenshealthmag.com/fitness/new-lunge-exercises?cm_mmc=Pinterest-_-womenshealth-_-content-fitness-_-newlungestotry
stability ball- ab leg twist. Rotate ball. Lie faceup with stability ball between ankles; hold ends of a 5- to 8-lb dumbbell and position on your chest. Lift legs to 45 degrees; extend arms to ceiling. Rotate legs to the right. Keep arms up and return legs to start.