Lie with your back flat on an exercise mat. Place your feet hip width apart and your toes slightly turned out. Ensure the heels of your feet are fairly close to your glutes and that your pelvis is tucked forward (ensuring you have no arch in your back whilst lying down). Lift one leg off the ground, keeping it bent at roughly a 90 degree angle. Focusing the tension in your glutes, push through the heel of your grounded leg and drive your hips up to full hip extension, exhaling as you do so and making sure to keep your heel pressed firmly into the ground. Pause for a count of one when your hips reach full hip extension, keeping the tension in your glutes and then return with control to the start position, inhaling as you do so. Repeat all the reps on one leg and then alternate to the other.