No sit-ups or crunches, this is the simple Pilates exercise I use to sculpt all of the muscles in my core

The plank to pike exercise is a powerhouse when it comes to working your core.
Woman&Home on MSN

I'm a Pilates instructor - this 15-minute workout strengthens the core without a single sit-up

Sit-up and crunches be gone - just 15 minutes of Pilates can build up core strength, and improve mobility and flexibility ...