FitNessieHow to do it
- Get into a plank with your hands about shoulder width apart, arms straight and back flat.
- Pull one knee in toward your chest, with the other leg extended behind you.
- Switch legs, pulling one knee out as the other comes in.
- Keep your hips down and run your knees in and out at a steady, fast pace.
Key cues
- Hands under the shoulders
- Hips stay down
- Knee toward the chest
- Quick, continuous switches
Common mistakes
- Piking the hips up
- Letting the hips sag
- Bouncing the hips instead of switching the legs
Muscles worked
- Primary
- Abs
- Secondary
- Obliques
Equipment
None.