The cable crunch is the ab exercise you can actually load and progress — kneel at a cable, curl your spine against resistance, and add weight over time. Here's how to do it with good form, the muscles it works, the mistakes to avoid, and how to program it.
The cable crunch is a loaded spinal-flexion exercise that primarily works the rectus abdominis (abs), with the obliques assisting. You kneel at a high cable holding a rope behind your head, then crunch by curling your ribcage down toward your pelvis against the resistance. Unlike bodyweight crunches, you can add weight to the stack over time, so it's one of the few ab exercises you can genuinely progressively overload — which makes it easy to track and improve.
The cable crunch isolates the front of the core through spinal flexion. The rectus abdominis does nearly all of the work, with the obliques helping and the hip flexors staying quiet as long as you move from the spine, not the hips.
| Role | Muscles | What they do in the lift |
|---|---|---|
| Primary mover | Rectus abdominis | Flexes the spine to curl the ribs toward the pelvis |
| Assisting | Obliques | Help flex the trunk and resist twisting |
| Assisting | Serratus anterior | Works with the abs to round the upper spine |
| Stabilizers | Hips, arms | Hold the kneeling position and the rope in place |
Step-by-step form for the kneeling cable crunch. The cue that matters most: move from the spine, keep the hips still.
If you want to train the same spinal-flexion pattern with a different setup or emphasis, these are the common swaps:
Because it's loadable, program the cable crunch like any other lift — pick a weight, chase reps, and add load over time. General starting points:
| Goal | Sets × reps | Notes |
|---|---|---|
| Strength | 3–4 × 8–12 | Heavier load, controlled tempo, hard squeeze at the bottom |
| Muscle size | 3 × 12–15 | Moderate load, full range, train close to failure on the last set |
| Frequency | 2–3× / week | Progress by adding a little weight or a rep when you hit the top of the range |
Loading the abs builds the muscle, but whether they show also depends on your body-fat level and nutrition — abs are built in the kitchen too. See cutting and nutrition for lifting for that side of it.
Log every set — weight and reps — in LiftHero, and because the cable crunch is loadable, it charts your progressive overload and flags personal records just like a barbell lift. Add rest-timer holds between sets, superset it with another core move, and save it into a routine so it's ready the next time you train. LiftHero records what you log; it doesn't diagnose your form.
It mainly works the rectus abdominis, the muscle that flexes the spine, with the obliques assisting. Because it's loaded, it lets you train the abs with progressive overload like any other lift.
The cable adds external resistance you can increase over time, so you can progressively overload the abs instead of just doing endless bodyweight reps. That makes it easy to track and progress.
From the spine. Keep your hips fixed and curl your ribcage toward your pelvis. If you fold at the hips or rock back to your heels, the movement becomes a hip hinge and the abs do less work.
Cable crunches build and strengthen the abs, but visible abs also depend on body-fat level and nutrition — abs are built in the kitchen too. Training the muscle and managing body fat both matter.
Treat it like any lift: about 3 to 4 sets of 8 to 15 reps works well. Add a little weight or a rep when you hit the top of the range.
Track your cable crunches, watch your load climb, and run a real program — free on iOS.
Download on theApp StoreFree to start · No interruptive ads · 14-day Hero trial
This guide is educational and not medical advice. Consult a qualified coach or medical professional before starting or changing a training program.
By Meitar Lazimi, founder of LiftHero · Last updated July 9, 2026.