Exercise guide
Negative Crunch
- Beginner
- Isolation
- Rep-based
- Waist
The Negative Crunch emphasizes the eccentric phase of the movement, increasing time under tension to build superior core strength and control. This variation is particularly effective for targeting the rectus abdominis while teaching proper spinal articulation.
Reviewed by the Crucible Fit team · Updated June 2026
Muscles worked
Setup
- Lie on your back with your knees bent and feet flat on the floor, hip-width apart.
- Place your hands lightly behind your ears or cross them over your chest.
- Perform a standard crunch to lift your shoulder blades off the mat to the peak contraction position.
How to do it
- Slowly lower your upper body back toward the floor, taking 3 to 5 seconds to complete the descent.
- Inhale deeply as you lower, maintaining constant tension in your abdominal wall.
- Stop the descent just before your shoulder blades touch the mat to keep the muscles engaged.
- Exhale and quickly crunch back up to the starting peak position to begin the next repetition.
Form checklist
- Keep your lower back pressed firmly into the floor throughout the entire movement.
- Maintain a fist-sized gap between your chin and your chest to avoid neck strain.
- Avoid pulling on your head with your hands; use your core to control the descent.
- Ensure the lowering phase is a smooth, consistent tempo without dropping at the end.
Pro tips
- Focus on 'unrolling' your spine one vertebra at a time to maximize muscle fiber recruitment during the negative.
- At the bottom of the negative, pause for a split second without letting your shoulders rest on the floor to increase intensity.
Make it harder
- Extend your arms straight overhead to increase the lever length and resistance against your core.
- Lift your feet off the floor into a 90-degree tabletop position to further engage the lower abdominals.
Frequently asked
- What muscles does the negative crunch work?
- The negative crunch primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
- What equipment do you need for the negative crunch?
- The negative crunch requires no equipment — just your body weight.
- Is the negative crunch good for beginners?
- Yes. The negative crunch is a beginner-friendly movement and a strong foundation to build on.