Jack Knife (One Leg)
- Body weight
1) Lie on your back on the floor - extend your legs out in front of you.
1) Curl up and lift yourself off the floor by tightening the core. As you do this, raise your right arm and left leg up and crunch in the middle - aim to touch your toes. Your body should look like a 'V' at the endpoint.
2) Now, gently lower yourself back to the floor.
3) Repeat on the other side.