Training guide
A cable crunch is a crunch you can load: you kneel under a high pulley with a rope held by your face and curl your ribs down towards your pelvis while your hips stay still. Because the cable adds weight in small steps, it's the usual next step once floor crunches are easy, and your six-pack muscle responds to it like any other muscle: hard sets, more reps, then more weight.
No study has tested the cable crunch itself, so this guide is honest about what the crunch, machine and spine studies do show: keep your hips still or your hip flexors take over, keep bending reps to about 60 a session, and don't expect it to flatten your stomach.
It covers the steps on the 3D figure, kneeling, standing and seated versions, how heavy and how many, your back and neck, and who should swap it for something else.
Kneel facing a high pulley with a rope, the ends held beside your face. Keeping your hips still, curl your spine so your ribs come down towards your pelvis and your elbows travel towards your thighs, then uncurl slowly against the cable. The American Council on Exercise (ACE) rates the standing version, facing away from the pulley, as a beginner exercise.
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Across 87 studies of ab exercises, bending the spine without bending at the hips, and adding load or an incline, raised the ab work most. In 42 adults, a machine crunch drew less six-pack activity and far more hip flexor activity than a ball crunch against an elastic band, so how you set up matters more than the equipment. No study has tested the cable crunch itself.
Curl-ups thickened the six-pack muscle in 70 women after birth, trunk training enlarged it in 64 older adults, and 10 weeks of machine crunches raised crunch strength by 36% in 16 men. Use the same rules as any lift: hard sets built up over weeks, more reps and then more weight. More weekly sets build more muscle, with diminishing returns.
The evidence here is indirect: sit-ups compressed the lower spine by more than 3,000 newtons in a computer model of 12 men, and a basic crunch about 2,000, as reported in an expert review. Pig spine segments bent tens of thousands of times under load damaged their discs, but that review judged loaded bending reasonable for healthy backs, at about 60 bending reps a session at most. No study has measured a cable crunch.
2 sets of 10 to 12 with 3 or 4 reps to spare for your first two weeks, then 3 sets of 10 to 12, stopping 1 to 3 reps short, with the last set within 0 to 2, and 60 to 90 seconds' rest. That's our editorial starting point, matching our gym ab workout. Do it 2 or 3 days a week, counting all your ab work, with every bending rep inside about 60 a session.
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Exercising a body part didn't reduce the fat over it across 13 studies of 1,158 people, and 6 to 12 weeks of ab exercise didn't shrink belly fat in two trials. Cable crunches build the muscle; your overall activity and eating decide the fat over it.
Leave it out with osteoporosis or a past spinal fracture: the UK consensus advises avoiding loaded spinal bending. In the first weeks after a birth the NHS advises avoiding exercises such as sit-ups and planks to start with. With a hernia, keep it light and stop if the hernia bulges, and in pregnancy use standing or side-lying core work.
A crunch against a cable: a rope on a high pulley, held by your face, and your trunk curling down so your ribs travel towards your pelvis while your hips stay put. Kneeling facing the stack is the usual version and the 3D demo. Standing with your back to the pulley is ACE's beginner version, and you can also do it seated, from an overhead start or with a twist.
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The rectus abdominis (the six-pack muscle) bends your spine, with the obliques at your sides helping. Your hip flexors join in if your hips fold or your feet are fixed. The movement is spine bending (flexion) under load. Our crunch guide explains the six-pack muscle in more detail.
It lets you add resistance in small steps, which floor crunches can't, and it's where our crunch guide's ladder ends. Added load or an incline raises the ab work. The cable doesn't make your abs special: they respond to hard sets like any other muscle.
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Controlled bodyweight crunches (the move page's prerequisite), and a neck and back that are comfortable with them. Our crunch guide takes you there.
Taller people kneel a little further back so the rope clears the head (our suggestion). In one computer model, an ab crunch machine fitted small users badly; a cable adapts to any size, one reason to prefer it.
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From the move page (the rope by the face, hips still, uncurling slowly) and ACE's standing crunch. The kneeling distance, the pause and the breathing cue are editorial, the breathing cue as in our crunch guide.
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The movement on the figure: Kneeling cable crunch
The move page's steps. ACE rates the standing crunch on a cable as a beginner exercise; use a lighter weight than kneeling (our suggestion).
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The movement on the figure: Standing cable crunch
We found no study of muscle activity, spine load or training in the cable crunch, and none comparing kneeling with standing. Everything below comes from floor, ball and machine crunches, computer models and reviews, so read it as the best available guide, not a test of this exercise.
In a synthesis of 87 studies, the ab muscles worked hardest when the spine bent without the hips bending, and inclines or added load raised the work. In 42 adults aged 28 to 67, a seated machine crunch drew 84% of maximum from the six-pack muscle and 65% from the rectus femoris (a hip flexor at the front of the thigh), against 104% and 27% for a ball crunch with an elastic band. When the hips and legs join in, the hip flexors take over: keeping your hips still is the point of the cable crunch's set-up.
In 14 people, the crunch was among the top exercises for upper and lower six-pack activity, and the bent-knee sit-up drew high hip flexor activity. In 8 adults with fine-wire electrodes, sit-ups worked the deep psoas, a hip flexor, at 15 to 35% of its maximum, the curl-up at under 10%.
In a trial of 70 women 6 to 12 months after birth, 12 weeks of curl-ups thickened the six-pack muscle by 0.7 mm and raised its strength. In 64 adults over 60, 12 weeks of trunk training enlarged it by about 2 square centimetres against walking and balance work alone. In 16 overweight men, 10 weeks of machine crunches raised crunch strength by 36%, against 17% with running alone. None of these used cable crunches.
Muscle activity measured in one session isn't a validated predictor of muscle growth, so the activity figures above show how hard the muscles worked, not what they will build.
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Kneeling cable crunch: 3 sets of 10 to 12 (our gym ab workout). Standing: 2 sets of 10 to 15, light (our editorial starting point). Seated, with your back to the pulley: 2 to 3 sets of 10 to 15 (our cable machine guide's starting point for small moves). From overhead: 2 to 3 sets of 8 to 12, stopping 2 or 3 reps short (the move page's dose); start light, as a heavy stack drags your shoulders. With a twist, elbow towards the opposite knee: 2 sets of 8 to 12 each side, lighter (our editorial starting point). The ab crunch machine: 2 to 3 sets of 8 to 12, stopping 2 or 3 reps short (the move page's dose); its hooked feet bring in the hip flexors more. The cable reverse crunch, which curls the pelvis up instead: 2 to 3 sets of 10 to 12 (our reverse crunch guide). The cable crunch on a Bosu dome has no 3D demo.
3D demoKneeling cable crunchIntermediate · A cable machine
3D demoStanding cable crunchBeginner · A cable machine
3D demoSeated cable crunchIntermediate · A cable machine + A bench or box
3D demoKneeling rope crunch from overheadIntermediate · A cable machine
3D demoKneeling cable crunch with a twistIntermediate · A cable machine
3D demoAb crunch machineBeginner · Strength machine
3D demoCable reverse crunchIntermediate · A cable machineNo study has measured spine load in a cable crunch. In a computer model of 12 young men, sit-ups compressed the lower spine by more than 3,000 newtons, with bent and straight legs alike. Across 12 ab exercises in 9 volunteers, partial curl-ups gave the most ab work for the spine's compression. An expert review reports about 2,000 newtons for a basic crunch. Adding a cable adds load, so it is reasonable to assume more compression than a floor crunch, but nobody has measured how much.
Pig spine segments bent and straightened up to 86,400 times under compression developed disc herniations, more often with more compression. An expert review points out that living spines adapt, sets are short with rests, and lab tissue can't remodel, and it judged dynamic bending exercise a reasonable risk for healthy backs, within about 60 bending reps a session.
A 3D model of an ab crunch machine predicted high loads between the vertebrae and a poor fit for small users, who also leaned on their hip flexors more. It's one model with no people measured, but it's a reason to keep the load moderate and the movement in your spine, not your hips.
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The expert review limits bending exercise only for people with disc problems or back pain that's worse bending forward. The UK consensus on osteoporosis advises modifying or avoiding sustained, repeated or end-range bending, and avoiding loaded bending.
Keep your hands by your face and your chin gently tucked; don't pull on your head. Our crunch guide covers the neck in more detail.
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If you feel it in your lower back or hips, your hips are probably moving and you're hinging rather than curling. Set your hips, use a lighter weight and curl your ribs to your pelvis. With back pain, aim for discomfort no more than about 5 out of 10 that settles within an hour or so and is no worse the next morning, and stop anything that sends pain down a leg, as our back pain guide says.
Your hips fold and your body weight pulls the stack. Set your hips and keep them still, as the move page cues.
Your hands stay by your face; let your trunk do the work.
A big stack turns it into a hip hinge. Choose a weight you could curl 10 to 15 times with 1 to 3 to spare, as our plans' starting-weight method suggests.
Chin gently tucked and no pulling on your head, as the ab studies advise.
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Breathe out as you curl. Holding your breath drives blood pressure up sharply in hard efforts, as our breathing guide explains.
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Uncurl slowly and don't let the plates touch down between reps.
Hold the rope's ends rather than the knots, or use a straight bar or an ab strap (our suggestion).
No study has tested cable crunch doses. These are our editorial starting points, reconciled with our gym ab workout, cable machine guide and crunch guide.
2 sets of 10 to 12, stopping with 3 or 4 reps to spare, with 60 to 90 seconds' rest, as our gym ab workout and our plans' starting note suggest.
3 sets of 10 to 12, stopping 1 to 3 reps short, with the last set within 0 to 2 (our gym ab workout). You don't need to go to failure: across 15 studies it gave a trivial growth advantage at most, and most people misjudge the reps they have left by about one.
2 to 3 sets of 10 to 15, the last set ending 0 to 2 reps short, with 60 to 90 seconds' rest: our cable machine guide's starting point for small moves, and the dose in our cable machine workout.
2 to 3 sets of 6 to 10, stopping 1 to 3 reps short (our editorial starting point, within the expert review's 6 to 15 reps for loaded bending work).
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About 60 bending reps a session at most, cable crunches, crunches and reverse crunches included, and at least 48 hours between bending sessions: one expert review's suggestion, untested, which our crunch guide and gym ab workout keep to.
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2 or 3 days a week counting all your ab work, as our crunch and get abs guides suggest; our gym ab workout itself is once or twice a week. The NHS asks adults for strengthening activities that work all the major muscle groups, including the abdomen, on at least 2 days a week.
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Add reps until every set reaches the top of the range, then move the pin one step and drop back to the bottom of the range. Adding reps and adding load both worked in a trial of 43 trained people. If the next plate is too big a jump, add reps first, as our cable machine guide explains.
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3 to 5 minutes of easy movement, a few slow cat-cows and a dead bug or short plank, then a light first set, as our plans and the NHS suggest.
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The weighted crunch, a plate or dumbbell held on your chest: 2 to 3 sets of 8 to 15, starting light (our crunch guide's editorial starting point). A long band anchored high, kneeling as for the cable, works the same way (no 3D demo; follow the kneeling steps above). The floor crunch, 2 sets of 12 to 20 stopping 1 to 3 short (our crunch and sit-up workout), is the step before.
Warm up with cat-cow, 8 waves, slower than feels natural (the move page's dose), a dead bug, 1 set of 6 each side, and a forearm plank, 1 hold of 20 to 30 seconds (both our gym ab workout). Round out your core with the Pallof press, 2 sets of 10 each side; hanging knee raises, 2 sets of 8 to 12; ab wheel rollouts from the knees, 3 sets of 6 to 10; and suitcase carries, 2 walks of 20 to 30 m each side (all our gym ab workout), plus side planks, 2 holds of 20 to 30 seconds each side (our full-body dumbbell workout B). With osteoporosis or a back that dislikes bending, bird dogs, 6 each side (our beginner core workout), and the Pallof press train your trunk without rounding.
3D demoCat-cowBeginner · No equipment
3D demoDead bugBeginner · No equipment
3D demoForearm plankIntermediate · No equipment
3D demoPallof pressIntermediate · A cable machine
3D demoHanging knee raiseIntermediate · Pull-up bar
3D demoAb wheel rollout from the kneesAdvanced · An ab wheel
3D demoSuitcase carryIntermediate · A dumbbell + A kettlebell
3D demoSide plankIntermediate · No equipment
3D demoBird dogBeginner · No equipmentOur gym ab workout has kneeling cable crunches with hanging knee raises, rollouts, Pallof presses and carries, kept to about 60 bending reps. Our cable machine workout pairs them with pushdowns. The crunch and sit-up, advanced core and beginner core workouts are the floor options.
A 25-minute gym ab workout you can add weight to: cable crunches, hanging knee raises, ab wheel rollouts, Pallof presses and suitcase carries.
25 minIntermediate7 movesA cable machine, Pull-up barA 40-minute full-body workout on a dual cable station in four pairs: pull-through and row, press and Pallof press, pushdown and crunch, raise and curl.
40 minBeginner14 movesCardio machine, A bandA 15-minute ab workout with a crunch track and a sit-up track, about 60 bending reps at most, plus a side plank and bird dog to balance it.
15 minBeginner10 movesNo equipmentHard core training: ab wheel rollouts, hanging leg raises, L-sits, Copenhagen planks, plank walk-ups and dragon flags.
30 minAdvanced6 movesAn ab wheel, Pull-up barA 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.
15 minBeginner6 movesNo equipmentLeave cable crunches out, as the move page says: the UK consensus advises avoiding loaded spinal bending, and notes reports of spinal fractures with repeated or loaded bending exercises such as sit-ups. Train your trunk with Pallof presses, dead bugs, bird dogs and carries instead, and get individual advice from a physiotherapist when you start.
Use the McGill curl-up and planks instead, as our crunch guide suggests, and see our herniated disc guide. The expert review limits bending exercise only for people with these problems.
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Crunches needn't be banned, but keep the load light (12 to 15 reps), breathe out on the effort, and leave out any move that makes the hernia bulge, as our hernia guide says. After an inguinal hernia repair, the NHS says no heavy lifting or strenuous activity for at least 4 to 6 weeks.
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The move page calls it an advanced core exercise after abdominal surgery or with a stoma: work up through easier core levels first, and stop if you notice doming or bulging around a stoma or scar. With a pulled stomach muscle, leave crunches out in the first days; our abdominal strain guide has the staged return.
Don't start loaded crunches new in pregnancy: the NHS doesn't recommend starting new vigorous activity, and says to stop if you feel uncomfortable, too hot or unwell. Swap them for standing or side-lying core work, as our crunch guide sets out.
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The NHS says to try to avoid exercises such as sit-ups, planks and high-impact exercises to start with, and to contact the GP if the gap between your tummy muscles is still obvious 8 weeks after the birth. Curl-ups didn't widen the gap in one trial, but no study has tested loaded crunches. If the middle of your tummy domes into a ridge, choose an easier move and see a pelvic health physiotherapist.
Breathe out on every rep and keep the load moderate: holding your breath drives blood pressure very high in hard efforts. The American Heart Association calls low- to moderate-intensity strength training with proper breathing safe when blood pressure is controlled, and advises against high-intensity training with active proliferative diabetic eye disease. Our breathing guide lists who should get advice first.
Leaking when you crunch or lift is common and treatable: a reason to see our pelvic floor guide and a pelvic health physiotherapist. See a GP about any leaking, as the NHS advises.
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If you get chest pain or pressure, feel faint or dizzy, are unusually breathless, or your heart races or beats irregularly during exercise, as our plans advise. The American Heart Association says these need immediate medical evaluation.
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For chest pain that comes on suddenly and doesn't go away, feels tight or like squeezing, spreads to your arms, neck, jaw, stomach or back, or comes with sweating, feeling sick, light-headedness or breathlessness; severe difficulty breathing; someone who faints while exercising; palpitations that don't go away, or come with chest pain, shortness of breath or feeling faint; or a headache that starts suddenly and is extremely painful, especially while lifting or straining, or comes with numbness or weakness, difficulty speaking or loss of vision. The NHS says a bleed on the brain may be more likely when lifting something heavy. Don't drive yourself to A&E.
Call 999 or go to A&E: loss of feeling or numbness around the genitals or bottom, new trouble peeing or controlling your bladder or bowels, changes in genital sensation during sex or problems with erections or orgasm, or pain, tingling, weakness or numbness in both legs. These are signs of cauda equina syndrome, which needs treating in hospital urgently. Don't drive yourself.
Same day (GP or NHS 111): back pain and you feel hot, cold, shivery or generally unwell, or severe pain that starts suddenly or is getting worse quickly.
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See a GP if you think you have a hernia, a bulge or lump that may get bigger when you strain and smaller when you lie down. Get help from NHS 111 if you have a hernia and pain in or around it, a bloated tummy, you feel or are sick, you're vomiting blood or your vomit looks like coffee grounds, you're constipated, you have a high temperature or feel hot, cold or shivery, or you've suddenly become confused. Call 999 or go to A&E for a femoral hernia (a small lump at the top of your thigh, in your groin) with very bad tummy pain, sickness, being unable to fart or poo, a high temperature or sudden confusion.
For a headache triggered or made worse by coughing, sneezing, bending down or exercising.
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See a GP if neck pain or stiffness hasn't gone after a few weeks, or comes with pins and needles or a cold arm, as our crunch guide says.
Speak to your GP first if you haven't exercised for some time or have medical conditions or concerns, as the NHS advises. Get advice before heavy lifting or hard straining work if your blood pressure is uncontrolled, or you have heart disease or chest pain when you're active, a pacemaker or defibrillator, diabetic eye disease, glaucoma, a hernia, recent eye or tummy surgery, or you're pregnant, as our breathing guide lists.
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Exercising a body part didn't reduce the fat over it across 13 studies of 1,158 people. Six weeks of ab exercise didn't shrink belly fat in 24 adults, and 12 weeks of ab training added nothing to diet alone in 40 women. One trial in 16 men found a little more trunk fat loss with 57 minutes of machine work 4 days a week, a result the larger evidence doesn't back. Ab work builds the muscle; your overall activity and eating decide the fat, as our get abs guide explains.
The idea comes from pig spine segments bent up to 86,400 times in a lab. Living spines adapt, sets are short with rests, and an expert review judged dynamic bending exercise a reasonable risk for healthy backs, within about 60 reps a session. The exceptions are disc problems, back pain that's worse bending forward, and osteoporosis. No study has tested cable crunches.
We found no study of the cable crunch. Added load raises ab work, but so do inclines and other loaded moves, and how you set up mattered more than the machine in one study. The cable's real advantage is small, measurable load steps.
Muscle activity in one session isn't a validated predictor of growth, so the crunch and machine figures on this page show effort, not results.
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Across 15 studies, training to failure gave a trivial growth advantage at most. Stop 1 to 3 reps short, as our plans say.
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Kneel facing a high pulley with a rope, the ends held beside your face. Keep your hips still and curl your ribs down towards your pelvis until your elbows near your thighs, then uncurl slowly against the cable. Start with a light weight.
Mainly the six-pack muscle (rectus abdominis), with the obliques helping. If your hips fold or you sit back on your heels, the hip flexors take over: in one study a machine crunch drew far more hip flexor activity than a ball crunch.
Either. Kneeling is the usual version and easier to load; standing, with your back to the pulley, is the version ACE rates for beginners. No study has compared them, so choose the one where you can keep your hips still.
Heavy enough that 10 to 15 reps leave 1 to 3 in reserve. There are no weight standards, and stack numbers differ between machines, so compare yourself with yourself on the same station.
Start with 2 sets of 10 to 12 with 3 or 4 reps to spare, then 3 sets of 10 to 12 with 60 to 90 seconds' rest, as our gym ab workout does. Add weight when every set reaches the top of the range. These are our starting points; no study has tested cable crunch doses.
Not for most healthy backs, though no study has measured the spine in a cable crunch. An expert review judged loaded bending reasonable for healthy spines within about 60 bending reps a session. Leave them out with osteoporosis or a past spinal fracture, and swap them if bending forward flares your back.
Usually because your hips are moving and you're hinging rather than curling. Set your hips, keep them still, use a lighter weight and curl your ribs towards your pelvis. If it still hurts, our back pain guide's rule applies.
They build the muscle; whether you see it depends on body fat. Exercising a body part didn't reduce the fat over it across 13 studies, so your overall activity and eating decide that part, as our get abs guide explains.
Both load a crunch. The machine's hooked feet bring in the hip flexors more, as one study found, while a cable lets you keep your hips still and fits any size. Use whichever you can do with your hips still.
Anchor a long band high and kneel as you would at a cable, or hold a weight on your chest for a weighted crunch, 2 to 3 sets of 8 to 15, starting light. Floor crunches with your arms overhead are another step up.
The NHS advises avoiding sit-ups and planks at first after a birth, and seeing a GP if the gap is still obvious at 8 weeks. Curl-ups didn't widen the gap in one trial, but no study has tested loaded crunches. If your tummy domes into a ridge, choose an easier move and see a pelvic health physiotherapist.
Don't start them new in pregnancy, and swap loaded crunches for standing or side-lying core work, as our crunch guide sets out. The NHS says to stop if you feel uncomfortable, too hot or unwell.
Exercise education, not a personal prescription, and clinical review of these guides is pending. Check with a GP before starting hard training if you have a heart condition, chest pain, dizziness or breathlessness when active, and stop for sharp or increasing pain. Health disclaimer.
