Standard Crunch
The standard crunch is a foundational bodyweight abdominal exercise that targets the abs through spinal flexion. It is widely used as a core strength builder and can be performed by individuals of all fitness levels.
How to do it
- Lie flat on your back with knees bent, feet flat on the floor, and hands placed lightly behind your head.
- Engage your core and curl your upper body off the floor toward your knees.
- Pause at the top of the movement, contracting your abs.
- Slowly lower your upper body back to the starting position.
- Repeat for the desired number of repetitions.
Form cues
- Keep your lower back pressed firmly into the floor throughout the movement.
- Lift your head and shoulders using your abdominal muscles, not your neck.
- Exhale as you curl up toward your knees.
- Lower down with control without letting your upper back crash onto the floor.
Breathing: Exhale smoothly as you curl your upper body up toward your knees, and inhale as you return to the starting position.
Common mistakes
- Pulling on your neck with your hands strains the cervical spine instead of working the abs.
- Using momentum to bounce up reduces the work done by your core muscles.
- Holding your breath limits oxygen flow and makes the exercise harder than necessary.
Muscles worked
Primary: abs. Secondary: obliques, hip flexors.
Suggested sets & reps
Get fitter
3 sets × 12–15 reps, rest 60 s
Lose weight
3–4 sets × 15–20 reps, rest 45–60 s
Build muscle
3 sets × 10–15 reps with a slow pause at the top, rest 60 s
Easier, harder & alternatives
Make it easier
Alternatives
Take care if…
- If you feel sharp lower back or neck discomfort, ease off and choose a gentler core movement.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
Should my lower back come off the floor during a crunch?
No, your lower back should stay in contact with the floor. Only your head, neck, and upper shoulders should lift.
Why does my neck hurt when I do crunches?
Neck strain usually happens when you pull your head forward with your hands. Support your head lightly with your fingers and lift with your abs.
How often can I do standard crunches?
You can perform them 2 to 4 times per week, allowing a day of rest between sessions for muscle recovery.