Exercise

Crunches: How to Do It, Muscles Worked

Last updated 26 July 2026

What muscles does the Crunches work?

The Crunches primarily targets the abdominals, with no listed secondary muscles in the dataset. It's classified as a beginner-level strength movement using no equipment.

What are the most common Crunches mistakes?

• Pulling on the neck with the hands instead of driving the movement from the abs.
• Letting the lower back arch off the floor or lose its brace during the movement.
• Using momentum to swing through reps instead of moving under control.
• Holding the breath entirely instead of breathing in a controlled way through the brace.

How should I program the Crunches — sets, reps and frequency?

As a core-stability exercise, it is usually programmed by 30-60 second holds, or 10-20 controlled reps, for 2-3 sets. It tolerates higher frequency than a heavy compound lift — twice a week for the same muscle group is common. Add difficulty gradually — more load, more distance/time, or better technique — rather than rushing intensity.

What are good Crunches variations and alternatives?

• Bent-Knee Hip Raise — bodyweight, beginner level, abdominals
• Hanging Leg Raise — bodyweight, expert level, abdominals
• Oblique Crunches — bodyweight, beginner level, abdominals
• Plank — bodyweight, beginner level, abdominals

Crunches at a glance

Attribute	Value
Level	Beginner
Equipment	Bodyweight
Category	Strength
Primary muscles	Abdominals
Secondary muscles	—

How to do the Crunches, step by step:

1. Step 1. Lie flat on your back with your feet flat on the ground, or resting on a bench with your knees bent at a 90 degree angle. If you are resting your feet on a bench, place them three to four inches apart and point your toes inward so they touch.
2. Step 2. Now place your hands lightly on either side of your head keeping your elbows in. Tip: Don't lock your fingers behind your head.
3. Step 3. While pushing the small of your back down in the floor to better isolate your abdominal muscles, begin to roll your shoulders off the floor.
4. Step 4. Continue to push down as hard as you can with your lower back as you contract your abdominals and exhale. Your shoulders should come up off the floor only about four inches, and your lower back should remain on the floor. At the top of the movement, contract your abdominals hard and keep the contraction for a second. Tip: Focus on slow, controlled movement - don't cheat yourself by using momentum.
5. Step 5. After the one second contraction, begin to come down slowly again to the starting position as you inhale.
6. Step 6. Repeat for the recommended amount of repetitions.