This exercise will lift your butt, sculpt your thighs and strengthen the muscles of the spine, hips and pelvis. You will develop core and pelvic stability by yielding better posture and the ability to maintain neutral spine alignment, which makes almost any activity easier.

• Lying on your back, arms at sides and palms down, bend knees, placing feet flat on floor and aligned with knees.
• Contract abs (draw in), bringing lower ribs and hips closer together to stabilize the pelvis, then straighten one leg to about a 45-degree angle, in line with other knee.
• Using the buttocks (gluteus maximus) and hamstrings, lift hips until body forms one straight line from shoulder to hips. Press your shoulder blades into the floor as you lift your hips.
• Keep spine extended and contract the butt and abdominal muscles, keeping equal tension between front and back of torso to maintain lifted position.
• Lower torso back to the floor as one unit, and repeat move for all repetitions (12-15).
• Repeat move with opposite leg lifted to complete one set.

Advanced Tip: Progress by keeping the lifted leg at calf height rather than at 45 degrees as you lift and lower your hips. For more of a challenge, attach a 2 to 5 pound ankle weight to the leg that's lifted.

Avoid: Don't use momentum to lift your hips off the floor; this can cause you to hyperextend your lower back.

Don't let one hip drop lower than the other; this will throw you off balance as well as lessen the effectiveness of the move.

Don't let the knee of the bent leg roll outward; this stresses the lateral side of the knee joint.