Simple set-up for a complex movement.
The ab wheel rollout is one my favorite anterior-core and posterior chain exercises and one I see butchered often. The way we set up dictates the efficacy and effectiveness of the drill.
1. Start in a full plank
2. Drop the knees to a 1/2 push-up position
3. Tuck the hips under by squeezing the glutes (saving the lumbar spine)
4. Tuck the ribs creating a hollow position. Think about pulling your belly button to your spine.
5. And most importantly, only rollout as far as good form allows. If you feel your ribs flare, back sink and neck crank you've lost it and are in danger of injury. Start shallow and work your way out into a deep roll for rock solid, carved abs and bulletproof back.