Lie on your front with your hands under your shoulders, palms down.
Push yourself up into a plank position with a straight line from your head to your heels.
Keeping good strength in your shoulders, push your hips back and up to make a "V" position with your body.
Focus on driving your hands into the floor and pushing your tail bone out.
Hold this position, then move back to the starting plank position.
Continue through this position to drop your hips down towards the floor.
Focus on not hunching, keeping your shoulders relaxed, your neck long and relaxing your back.
You should feel a gentle stretch in your back.
Hold this position, return to the starting position and repeat.