Crunch

Why it matters

The crunch is a simple, accessible way to learn the basic spinal-flexion pattern that underlies most other ab exercises. While more advanced movements eventually offer more benefit per minute, the crunch remains a reasonable, low-risk starting point for building initial ab awareness and control.

How to do it

1. Lie on your back, knees bent, feet flat on the floor. Hands lightly behind your head or crossed over your chest.
2. Curl your shoulders up off the floor. Lead with your chest moving toward your knees, not your chin jutting forward.
3. Stop a few inches up. A full sit-up isn't necessary or even more effective — the crunch is a short-range movement by design.
4. Lower with control. Return to the starting position without letting your head drop quickly.

Common mistakes

• Pulling on the neck with the hands. Hands behind the head should lightly support, not yank the head and neck forward.
• Using momentum to jerk upward. A controlled curl engages the abs more than a fast, swinging motion.
• Lifting too high, into a full sit-up. Going beyond the crunch's natural short range brings in hip flexors more than additional ab benefit.
• Holding the breath throughout the set. Breathe normally — exhaling on the way up is a common, helpful cue.

Sets & reps by level