This is a simple one to work your core.
How To Do It:
1. Clasp your hands together in front of your body (at chest level) with your elbows out.
2. Raise you right knee as you twist so that your left elbow goes towards the knee (without dropping your arms from chest level. i.e.. the goal is not to bring the elbow to the knee).
3. Repeat on the other side.
4. Do this thirty times on each side as many times today as possible.