Bird dog is a posterior core exercise which teaches you to prevent excessive flexion, rounding, of your spine.
- Get on all fours, with your knees under your hips and your hands under your shoulders. Remember to keep abs engaged and keep your back flat.
- Reach out with your right hand and extend your left leg out behind you.
- Round your back and head to connect your right elbow with your left leg under your body. This completes one rep.