This exercise strengthens glutes, hamstrings and your core as you contract both the lower back and abdominal muscles.
Start by lying on the floor with your feet flat on the mat and knees bent. Raise your left leg off the mat pulling the knee to your chest. Keeping your core and glutes engaged execute the movement by pushing your hip upward and raising your glutes off of the mat. Keep your belly button pulled in and hold for 20-30 seconds. Do 2-3 sets 8-12 reps.