This exercise can reshape a flabby buttocks in no time!  Along with defining your buns and the back of your thighs, you’ll develop more core stability, which translates to better posture and stronger muscles.  You will feel this exercise mostly in the buttocks muscles and the top of rear thigh of the leg you have lifted.  You will also feel your abs and all the muscles of the torso, chest, shoulders and arms contract to maintain your balance.

• Drape yourself facedown over a stability ball, then walk your hands forward on the floor until your shins are on the ball, legs and ankles together and wrists aligned under your shoulders, arms straight but not locked.
• Pull your abs up and in, so your body forms a straight line from head to heels, shoulders drawn down and away from your ears.
• Maintaining this position, keeping hips squared and level, press your right leg against the ball as you lift your left leg a few inches off the ball. 
• Pause and then lower and repeat with the other leg, alternating repetitions.
• Do 2-3 sets of 10-16 alternating reps, resting 30-60 seconds between sets.  After 4- 6 weeks, progress to Advanced Tip.

Advanced Tip:  For more of a challenge, do all repetitions with 1 leg, then switch legs and do reps to complete 1 set, or secure a 2-3 pound cuff weight around your ankles.
Strengthen your abs by keeping your body still and stabilized as you slowly lift and lower each leg to really zero in on toning your butt.

Tips To Avoid: 
Don’t let your belly sag as you lift your leg, it will destabilize your body and places undue stress on your lower back.
Don’t lift your leg to high; this can hyperextend your lower spine.
Don’t let your shoulders sink, hang your head or shift your upper body forward, it places to much tension on the connective tissue of the wrists, elbows, and cervical spine.