You don't need disc sliders for this exercise; just grab a pair of towels and get to work.
- Begin in plank position with two towels under the balls of your feet (or paper plates if you're on carpet).
- Slowly bend both knees in toward your chest while keeping your arms straight, shoulders over your wrists, and maintaining a flat, tabletop back. If this is too difficult, draw one knee in at a time.
- This counts as one rep.
- For a variation, draw both knees to your right foot, straighten your legs back behind you, then draw both knees to your left foot.
- This counts as one rep.