Skip to content
ascend.
Exercise guide

Crunches

How to do the Crunches with correct form, the muscles it works, and where it fits a training plan you actually stick to.

IsolationBody OnlyBeginnerPull
Primary muscles

Abs

Secondary

Equipment

Body Only

Step by step

How to do the Crunches

  1. 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. 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. 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. 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. 5

    After the one second contraction, begin to come down slowly again to the starting position as you inhale.

  6. 6

    Repeat for the recommended amount of repetitions.

In Ascend

Log it, see it on your body.

Every Crunches set you log feeds Ascend's anatomy heatmap — so your abs volume is visible at a glance — and counts toward your bodyweight-strength tier.

Related

More abs exercises

Ascend Club

The app is free. Club adds the coach, leagues and analytics.

Core tracking stays free forever — the climb, streaks, logging and your league tiers. Club is for when you want the full coach, worldwide competition and the depth, at about the price of one coffee a month.

See Club plans

14-day free trial · no card to start

 FreeClub
Tracking, the climb and streaks
Per-set logging, PR detection, wearables
Muscle-league tiers
The AI coachnudgesFull conversation
Worldwide leagues and challenges
PR projections and deep analytics
Unlimited crews
Themes, export and higher AI limits