Strength Training · Bodybuilding · Calisthenics
Crunch
The crunch trains your abs by curling your upper back a short distance off the floor while your hips stay down. It uses a smaller range of motion than a sit-up.
- Beginner
- Isolation
- Low injury risk
- Rest 45 sec
How to do it
- Lie on your back with your knees bent and feet flat on the mat, hip-width apart.
- Cross your arms over your chest.
- Curl your ribs toward your pelvis until your shoulder blades clear the mat.
- Lower your upper back to the mat to finish the repetition.
Form cues
- Exhale as you curl up.
- Keep space between your chin and chest.
- Let your abs do the work.
Common mistakes
- Swinging through repetitionsTake about two seconds to lift and two seconds to lower.
- Turning the crunch into a sit-upStop the upward movement before your lower back starts leaving the mat.
- Pressing your head forwardLet your head follow the curve of your upper back rather than leading the movement.
Safety
Jerking your head or forcing extra repetitions when fatigued can strain your neck. Repeated spinal bending may also aggravate an already sensitive lower back.
- Keep your head and upper back over the mat so they land on a padded surface.
- End the set when you can no longer maintain the same controlled movement.
- Stop if you feel neck or back pain rather than abdominal effort.
If bending your spine triggers back pain or you have an ongoing neck problem, ask a physiotherapist about a suitable alternative.
Muscles worked
Primary muscles
Equipment
- Exercise Mat
Sets and reps
- Sets
- 2–3
- Target
- 10–20 reps
- Rest
- 45 sec
Start at the lower end of the range, leaving a few controlled repetitions in reserve.