Work your abs, and tighten your thighs with this exercise.

1) Lie on your back, with arms extended behind head, knees bent with toes touching the floor

2) Keeping your right knee bent, lift it while bringing your left arm up and out to touch the right toe.

3) Alternate, bringing right arm up to touch left toe.

4) Keep the non-moving leg firmly on the floor.

5) Repeat for 10 reps; build to 25 reps