- Place the towels under your toes in plank position, with your feet slightly apart.
- Bend your right knee and slide your right toe up toward your right elbow.
- Slide your toe back to neutral plank position, and lift your foot off the towel. This completes one rep.
- Repeat on the same side five times, then complete five reps on the other side.
- Modification: you can do this without the leg lift.