How to do the cable crunch

The cable crunch is the easiest way to train your abs like any other muscle: with a weight you can measure and increase. Floor crunches stop being hard once you can do 30 of them, and at that point more reps mostly build endurance. Kneeling under a cable lets you pick a load that makes 10 to 15 reps tough, then move the pin down as you get stronger. It's also simple to learn, and most gyms have a cable station free.

How to do a cable crunch

1. Set a rope on a high pulley and kneel facing the stack. Kneel about one to two feet (30 to 60 cm) back from the machine, knees about hip width apart.
2. Hold the rope beside your head. Grab it with your palms facing each other and bring your hands to either side of your forehead or ears. Your hands stay there for the whole set.
3. Set your hips and lean forward slightly. Sit your hips up off your heels, so your thighs are close to vertical, and lean your torso slightly forward from the hips. You should feel the cable pulling your upper body up and back, with a stretch through your stomach.
4. Crunch by curling your ribs toward your pelvis. Round your spine from the top down, bringing your elbows toward the middle of your thighs. Your hips stay where they are. Breathe out hard as you go.
5. Stop when your spine is fully rounded. Your elbows end up around your thighs or just above your knees, and your forehead points at the floor. Hold for a second and squeeze.
6. Uncurl slowly back to the start. Take two to three seconds, letting your spine lengthen until you feel the stretch in your abs again. Don't let the weight stack touch down between reps.

The movement is small and it happens in your spine. If your hips are folding back toward your heels, the weight is moving but your abs aren't doing most of the work.

Cues that help

"Ribs to your hips." Think about shortening the distance between your lower ribs and your pelvis. It keeps the crunch in your spine rather than your hips.

"Curl like a pill bug." Roll your spine forward one section at a time, top to bottom. If that doesn't click, try "look at your belly button".

"Hands are glued to your head." Your arms are hooks, not movers. It stops you pulling the rope down with your arms and shoulders.

"Hips stay tall." Keep your hips high and still. If they drop back, you've turned the crunch into a bow.

Common mistakes

Sitting back into your heels. It looks like a bow: the hips fold back, the backside drops toward the heels and the torso tips forward in one piece with a flat back. The usual cause is a weight too heavy for your abs, so your hips and body weight take over. Drop the load and keep your hips up and still while your spine does the bending.

Pulling with your arms. The hands move away from the head and the rope travels down in front of your face, like you're pulling a lawnmower cord. Your lats and arms end up doing the work. Keep your hands fixed beside your head and let the crunch carry them down.

Letting the weight yank you back up. The stack rises fast and pulls your torso upright in half a second. You lose the slow stretch on the way back, which is a big part of what makes this exercise work. Count two or three seconds on the way up.

Going far too heavy. A full stack moved with a big hip swing and a few inches of spinal movement is a common sight. Your abs grow from the range they move through, not the number on the pin. Use a weight you can crunch fully for 10 clean reps.

Breathing

Breathe out forcefully as you crunch. Pushing the air out lets your ribs drop further toward your pelvis, so you get a deeper crunch and a harder squeeze. Breathe in as you return to the start. Holding your breath throughout is a hard habit to break on ab exercises, so it's worth being deliberate here.

Sets, reps and how much weight to use

Do 3 sets of 10 to 15 reps, with a weight that leaves you two or three reps short of failure. Cable crunches fit at the end of a session, once or twice a week, and pair well with a hold like the plank on another day.

As with any cable exercise, the numbers on the stack don't compare between machines, but somewhere around 30 to 50 lb (15 to 25 kg) is a common starting point. Don't be surprised if you can handle more than you'd expect, and don't chase it. Once you can do all your sets at 15 reps with a full range, move the pin down one plate and drop back to 10. It's the same progressive overload you'd use on a squat.

That's why we'd pick the cable crunch as the main ab exercise for most gym-goers. It's measurable, and measurable things get stronger. Logging your sets in Helthy means you'll know what you did last time and can aim for one more rep.

Is flexing your spine under load safe?

There's real debate about this. Some researchers argue that repeated spinal flexion wears on the discs, and much of that argument comes from lab studies on animal spines bent thousands of times without rest. Others point out that a living spine adapts to load like the rest of your body, and that a few sets of crunches a week is nothing like that lab setup. For a healthy back, moderate loads for 10 to 15 reps are a reasonable default.

If you have a disc injury or crunches bring on back pain, switch to exercises that hold your spine still, like the plank. If the pain doesn't settle within a week or so, get it looked at.

Variations and alternatives

• Standing cable crunch: face away from the stack and crunch forward while standing. Easier to set up, harder to keep the hips out of it.
• Kneeling oblique cable crunch: crunch diagonally, bringing one elbow toward the opposite knee. Adds more work for the obliques.
• Machine crunch: a seated ab machine with a fixed path. A good alternative if your gym's cables are always busy.
• Weighted decline crunch: hold a plate to your chest on a decline bench. The best free-weight swap.
• Band crunch: loop a resistance band over a door or pull-up bar for a home version.
• Hanging leg raise: harder, bodyweight-only, and it also trains your grip. A good second ab exercise once you've built some strength here.

Cable crunch questions

Are cable crunches better than regular crunches?

For building strength and muscle, yes, mostly because you can add weight in small steps. Regular crunches are fine for beginners, but once you can do 25 or 30 easily, a cable gives you somewhere to go.

Will cable crunches make my waist thicker?

Not noticeably. The abs are thin, flat muscles, and training them doesn't widen your waist the way people fear. A thicker waist nearly always comes from body fat.

Why do I feel cable crunches in my arms or hips?

Arms usually means you're pulling the rope down; keep your hands fixed beside your head. Hips means you're sitting back instead of rounding your spine. Lighten the weight and aim for a smaller, cleaner crunch.