Training guide
Your core is more than your abs: it's the muscles that wrap your trunk, from your diaphragm to your pelvic floor, front, sides and back. To strengthen it, train each job it does: holding against arching, sideways bending and twisting, keeping your back straight, curling, and carrying. Two or three short sessions a week are enough.
This guide covers what the core is, core stability and core strength, one exercise for each job with steps from easiest to hardest, how to test yourself and what's typical, what the trials show for sport, balance and back pain (core training helps, but it isn't magic), crunches against planks, and who should change it. A free core strength workout puts it into one session.
It's the box of muscles around your trunk: the diaphragm on top, the abs and obliques at the front and sides, the back muscles and glutes behind, and the pelvic floor and hips below. Core stability is control of your trunk over your pelvis; core strength is how much force it can resist or make.
Resist arching (planks, dead bugs), bending sideways (side planks, suitcase carries) and twisting (Pallof presses), keep your back straight (bird dogs), curl (curl-ups, reverse crunches) and carry. No single exercise trains every ab muscle with a low load on the spine.
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One move per job, 2 or 3 sets, made harder rather than longer (our editorial starting point, as our abs and plank guides do). Core training raised core endurance a lot in pooled trials of athletes, though the trials were small and varied.
It improves core endurance and balance, jump height a little, and balance and reach in older adults. It hasn't been shown to improve sprinting, agility or sport skill.
Exercise eased chronic back pain by about 15 points on a 100-point scale across 249 trials, and core exercise helped no more than other exercise. A strong core didn't prevent back pain on its own in a trial of 4,325 soldiers.
Swapping sit-ups for core stability work gave the same sit-up scores and injury rates in thousands of soldiers. The idea that crunches wreck your discs comes from pig spines bent tens of thousands of times in a lab. With osteoporosis, avoid loaded rounding of your back.
There's no single definition. A useful one is a box: the diaphragm on top; the six-pack muscle (rectus abdominis), the obliques and the deep transversus abdominis at the front and sides; the back muscles (erector spinae, multifidus and quadratus lumborum) and the glutes behind; and the pelvic floor and hip muscles below.
Core stability is control: keeping your trunk where you want it over your pelvis while your arms and legs move or something pushes on you. Core strength is how much force those muscles can resist or make. Everyday life mostly needs low-load control; lifting and sport need more strength. There's no gold-standard test of either.
Stop arching: planks, dead bugs and ab wheel rollouts. Stop bending sideways: side planks and suitcase carries. Stop twisting: Pallof presses. Hold your back straight: bird dogs and back extensions. Curl: curl-ups, reverse crunches and crunches. Carry: farmer's and suitcase carries, which use all of the above as you walk (our grouping, as our plank, oblique and ab challenge workouts use).
Visible abs depend on the fat over them; core strength doesn't. Core work strengthens the muscles but doesn't burn the fat over them, as our abs and belly fat guides explain.
Heavier and broader people score lower on hold tests, women tend to outlast men on a back-extensor hold, and back-muscle endurance is shorter in older adults. None of this is a target: compare yourself with yourself.
Most core training trials are small and of low quality, with very different programmes (high heterogeneity) and a risk that positive results were more likely to be published.
In 8 trials of 169 athletes, core training improved core endurance (a standardised effect of 0.90), plank time and balance (0.81). In 29 studies of 956 athletes, core endurance improved by 1.32 and balance by 0.99. Across 21 studies, balance improved by 1.17 and vertical jump by 0.69, with moderate certainty, but not throwing speed.
The same pooled trials found no clear gain in sprinting, agility or sport-specific performance. In trained people, core training raised trunk strength a lot but performance only a little, and trunk strength barely tracked performance. An earlier review of 24 studies called the benefit to athletic performance marginal.
In older adults, core training raised trunk strength by about 30% and balance and function by about 23%, in low-quality trials. In 11 studies of 442 people aged 60 to 85, it improved reaching and walking tests and one-leg standing. Falls weren't measured.
Across 249 trials, exercise reduced chronic low back pain by about 15 points on a 100-point scale compared with no treatment, with moderate certainty, and improved function a little. Most types of exercise beat minimal treatment in 217 trials, with Pilates and McKenzie exercises among the larger effects, and the authors advise choosing the exercise you enjoy.
In 29 trials of 2,431 people, deep-core "motor control" exercise wasn't clinically better than other exercise for chronic back pain, and in another review of 29 studies, stabilisation exercise wasn't better than other active exercise in the long term.
Exercise with education cut the risk of a new episode of back pain in 21 trials of 30,850 people (risk down by about 45%, moderate quality). But in 4,325 soldiers followed for 2 years, core stability exercise prevented no more back pain than traditional sit-ups and crunches, and across 26 cohort studies, trunk muscle endurance didn't predict who got back pain.
In 928 Danish adults, good back-muscle endurance went with less first-time back trouble in men over a year, and in 126 people, poor endurance went with more new back pain. Later pooled cohort studies didn't confirm a link.
In 2,616 soldiers, 12 weeks of core stability work instead of sit-ups gave the same sit-up scores and fitness. In 1,141 soldiers, injury rates were the same, with slightly fewer days off for back injuries in the core stability group.
Pig spine segments bent up to 86,400 times under load in a lab developed disc bulges. That's not evidence from people training. In 9 people, partial curl-ups gave the most ab work for the load on the spine, and no single exercise trained all the ab muscles at a low spine load.
Six weeks of ab exercises on 5 days a week changed no measure of belly fat in 24 adults, though their curl-up test rose. Across 13 studies, training one body part didn't take the fat off it.
We found no trial of the best dose of core training for the general public. The doses below come from our own workouts and are our editorial starting point.
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Four to six moves a session, one for each job, from the steps below.
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Two or three sets of each. Front planks of 20 to 45 seconds and side planks of 15 to 40 seconds, ending each hold when your form goes; once 3 holds of 45 seconds are steady, make it harder rather than longer, as our plank guides say. Moving exercises: 6 to 15 reps, stopping 1 to 3 short. Carries: 20 to 30 metres a side (our editorial starting points, from our ab challenge and plank challenge workouts).
Two or three times a week, on its own or at the end of a strength session, as our abs guide suggests. Modest daily holds are fine too, as our plank hold guide says.
Brace: tighten all the way round your middle as if for a light poke in the stomach, keep your ribs down and keep breathing, as our plank guide's cue says. Sucking your belly button in hard isn't needed.
Never hold your breath in a hold: blood pressure climbs in long planks, as our plank guide explains. Counting out loud helps.
Heavy squats, deadlifts and carries work your trunk hard too, as our abs and plank guides explain, so a full strength plan already does part of the job. Core work adds to it.
Our editorial starting point, built on our ab challenge sessions, our plank guides' cues and our core strength workout.
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The movement on the figure: Dead bug
Pick one from each job, 2 or 3 sets, 2 or 3 times a week; our core strength workout and ab challenge sessions give the doses.
3D demoForearm plankIntermediate · No equipment
3D demoDead bugBeginner · No equipment
3D demoSide plankIntermediate · No equipment
3D demoHalf-kneeling Pallof pressBeginner · A band + An anchor point
3D demoBird dogBeginner · No equipment
3D demoMcGill curl-upBeginner · No equipment
3D demoReverse crunchIntermediate · No equipment
3D demoSuitcase carryIntermediate · A dumbbell + A kettlebell
3D demoFarmer's carryIntermediate · A dumbbell + A kettlebellEasier steps for each job: move on when every hold or set reaches the top of its range for 2 sessions.
Harder versions of each job. The straight-arm plank's move page gives 3 holds of 15 to 30 seconds as a suggested starting point; the long-lever plank has no demo of its own, so the forearm plank shows it.
3D demoStraight-arm plank (high plank)Intermediate · No equipment
3D demoPlank walk-upAdvanced · No equipment
3D demoAb wheel rollout from the kneesAdvanced · An ab wheel
3D demoSide plank with leg liftAdvanced · No equipment
3D demoHollow body holdIntermediate · No equipment
3D demoSupermanIntermediate · No equipment
3D demoHanging knee raiseIntermediate · Pull-up bar
3D demoCopenhagen plankAdvanced · A bench or box
3D demoBear crawlIntermediate · No equipmentIn 471 college students holding a forearm plank until their form went, the median was 110 seconds for men and 72 for women, and most stopped because of their legs or arms, not their abs. Our plank test page scores ages 18 to 40 against this table; test every 4 to 8 weeks, fresh and the same way (our suggestion).
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The back researcher Stuart McGill's tests time a back-extensor hold, a front-of-trunk hold and side planks. They were highly reliable in 75 young adults, and their targets are ratios between the holds rather than times for your age: in men, side planks lasted about as long as the front hold. A big difference between your two side planks is something to train, not a diagnosis (our suggestion).
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Hold times ranked people consistently but varied by 12 to 24% between tries in 45 athletes, were lower in heavier and broader people, and were about 41 seconds shorter for the back muscles in people over 60. They don't predict back pain. Compare yourself with yourself.
Core exercises, Pilates, McKenzie exercises and general strengthening all help chronic back pain by roughly similar amounts, so choose what you enjoy and will keep doing.
Start with moves your back tolerates: dead bugs, bird dogs, side planks and the McGill big 3. Our back pain rule: discomfort up to about 5 out of 10 is acceptable if it settles within an hour or so and is no worse the next morning, and stop any move that sends pain down a leg. Our back pain guides have the plans.
Exercise with education lowers the risk of a new episode of back pain, but core work on its own did no better than sit-ups in a large trial. Keep active in whatever way suits you.
Core work is worth a short slot for trunk endurance and balance, while speed and skill come from your sport and from strength and power training. Don't expect core work alone to make you faster.
Trunk training went with better balance and reach in older adults. Our older adults guide puts it with leg strength, balance work and walking, which is what lowers the risk of falls.
Children build strength through active play and sport; our children's exercise guide covers it. For a baby or toddler, ask your health visitor or GP.
Our core strength workout trains every job in one session, with easier and harder steps. The ab challenge sessions split the jobs over two short sessions, and the McGill big 3 suits a back that dislikes bending.
A 25-minute core strength workout: planks or rollouts, side planks, a band Pallof press, bird dogs, curl-ups and a carry, each with an easier and a harder step.
25 minBeginner11 movesAn ab wheel, A bandA 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.
15 minBeginner6 movesNo equipmentA 12-minute core session for the front of the trunk: dead bugs, curl-ups or crunches and front planks, each with steps from beginner to harder.
12 minBeginner11 movesNo equipmentA 12-minute core session for the sides and back: side planks, bird dogs, a band press that resists twisting and an optional one-sided carry.
12 minBeginner10 movesA band, An anchor pointA 12-minute plank session for the 30-day plank challenge: front planks that get harder, not longer, plus side planks and bird dogs for the whole trunk.
12 minBeginner12 movesNo equipmentA 25-minute oblique workout at home: side planks, a band Pallof press and a suitcase carry to hold your trunk steady, then slow Russian twists and side-lying crunches.
25 minIntermediate8 movesA band, An anchor pointA 25-minute carry workout with dumbbells or kettlebells: farmer's carries, suitcase carries on each side and an overhead carry, with a safe pick-up first.
25 minBeginner7 movesA kettlebell, A dumbbellThe McGill big three for the core: curl-ups, side planks and bird dogs, each held for 10 seconds at a time in falling sets of 5, 3 and 1 reps.
12 minBeginner3 movesNo equipmentA 20-minute floor workout for your back muscles: bird dogs and bridges, then a face-down ladder from the locust to the superman, with side planks and dead bugs.
20 minBeginner13 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 20-minute ab wheel ladder: planks, fallouts, kneeling rollouts to a wall and at full reach, barbell rollouts from a bench, then standing rollouts.
20 minBeginner8 movesAn anchor point, An ab wheelA 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 barTwenty minutes of plank, side plank, boat pose, back lifts and standing balances: the yoga poses that work the trunk hardest, with easier and harder options.
20 minBeginner13 movesNo equipmentTen minutes of the classic Pilates abdominal series: the hundred, the roll-up and the series of five, with a plank to finish.
10 minIntermediate11 movesNo equipmentThe 30-day ab challenge trains every part of your trunk in four short sessions a week; the plank challenge builds your holds, harder rather than longer.
A free 30-day ab challenge: four 12-minute core sessions a week, from dead bugs to hollow holds, with rest days and an honest word on belly fat.
4 training days12 minBeginner3 days a weekA free 30-day plank challenge that gets harder, not longer: three plank sessions a week, two optional McGill big 3 days and a plank test at each end.
3 training days12 minBeginner3 days a weekA free 4-week, 3-day Pilates plan for complete beginners. Two mat days and one wall day, with clear rules for when to move each exercise to its harder version.
3 training days25 minBeginner3 days a weekA 3-day workout plan: three full-body gym sessions a week, alternating workouts A and B, with sets, reps, rest and an 8-week progression.
3 training days45 minBeginnerIn later pregnancy, the NHS advises avoiding lying flat on your back for more than a few minutes, which can make you feel dizzy. Our rule starts after the first trimester: swap crunches for side-lying, all-fours or standing core work, as our pregnancy guide sets out.
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The NHS advises avoiding sit-ups, planks and high-impact exercises to start with, and contacting a GP if the gap is still obvious 8 weeks after the birth. Later, curl-ups needn't be banned: 12 weeks of curl-ups didn't widen the gap in a trial. If the middle of your tummy domes (bulges into a ridge), make the move easier, as our diastasis recti guide explains.
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With osteoporosis or a past spinal fracture, avoid repeated or loaded deep rounding of the back, and bend from the hips. The osteoporosis guide covers impact and lifting.
The British Heart Foundation advises avoiding "using your whole body as a weight, such as press-ups or planks", and holding your breath. Ask your heart team; dead bugs and bird dogs are gentler.
Eye pressure rose during planks in healthy volunteers. Ask your eye team before long holds, and breathe throughout.
Our suggestion, as our abs and plank guides do: after an umbilical or incisional hernia repair, or with a stoma, our hernia and stoma guides set the order of core moves, and stop any move that makes a bulge appear.
Our suggestion: our pelvic floor and prolapse guides come first; with a prolapse, swap twists and crunches for Pallof presses, as our oblique workout suggests.
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 pain spreading down a leg hasn't improved after a few weeks of home treatment, is getting worse or stops your normal activities. Sciatica on both sides, or weakness or numbness in both legs that's severe or getting worse, is a 999 call or a trip to A&E.
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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.
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.
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.
Ask for an urgent GP appointment or get help from NHS 111 for a headache that's triggered or made worse by coughing, sneezing, bending down or exercising. In the US, contact your doctor or urgent care.
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Stop straight away if you feel any pain or become unwell, the NHS says, and contact 111 if your symptoms worry you or don't go away.
A dull ache in your muscles for a day or two after something new is normal. Joint pain that's sharp, gets worse during a set or lingers into the next day means switching to the easier option, and seeing a GP or physiotherapist if it carries on (our plans' rule). Our muscle soreness guide has more.
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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. After a recent shoulder dislocation or shoulder surgery, follow our shoulder dislocation guide or your surgical team first.
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Crunches train one job, curling. No single exercise trains every core muscle with a low load on the spine, so a strong core also needs work against arching, sideways bending and twisting, and for your back.
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The idea comes from pig spines bent tens of thousands of times in a lab. Swapping sit-ups for core stability work in thousands of soldiers changed neither injury rates nor sit-up scores. With osteoporosis, or if bending sends pain down a leg, leave them out.
Trunk endurance didn't predict back pain across 26 cohort studies, and core stability work prevented no more back pain than sit-ups over 2 years in 4,325 soldiers. Exercise with education does lower the risk.
They help about as much as other exercise, not more. Choose the exercise you enjoy.
Core training raised core endurance and balance, but not sprinting, agility or sport performance, in pooled trials.
Long holds mostly end at the arms and legs. Make the plank harder, not longer.
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Six weeks of ab exercises changed no measure of belly fat, and training one body part doesn't take the fat off it.
Train each job your trunk does: a plank or dead bug, a side plank or suitcase carry, a Pallof press, a bird dog and a curl-up, 2 or 3 sets each, 2 or 3 times a week. Make each one harder over time rather than longer.
It's how well the muscles around your trunk (your abs, obliques, back muscles, diaphragm, pelvic floor and hips) hold you steady and make force, so your arms and legs have a stable base. It isn't the same as visible abs.
Stability is control: keeping your trunk steady while your arms and legs move. Strength is how much force your trunk can resist or produce, which matters more in lifting and sport.
There's no single test. Time a forearm plank and each side plank every few weeks and compare with yourself; times vary a lot between tries and fall with age, so a single number says little.
Core endurance tests improve within weeks: in trials, core training raised plank times and core endurance over 4 to 12 weeks. How it feels in everyday life varies from person to person.
No: 2 or 3 sessions a week is plenty, though modest daily holds are fine if you enjoy them. A full strength plan already works your trunk through squats, deadlifts and carries.
They do different jobs, so a mix is best: a plank resists arching and a crunch curls the trunk. Swapping sit-ups for core stability work in soldiers changed neither sit-up scores nor injuries.
Not on its own: trunk endurance didn't predict back pain in cohort studies, and core stability work prevented no more back pain than sit-ups in a large trial. Exercise does help existing back pain, and core work is one good option among several.
Choose moves your back tolerates, such as dead bugs, bird dogs, side planks and the McGill big 3, keeping discomfort to about 5 out of 10 and settling within an hour. Core exercise helps about as much as other exercise, so pick what you enjoy, and see our back pain guides.
Brace: tighten all the way round your middle as if for a light poke in the stomach, keep your ribs down and keep breathing. Sucking your belly button in hard isn't needed.
It improves core endurance and balance, and jumping a little, but pooled trials found no clear gain in sprinting, agility or sport skill. Keep it as a short part of your training.
Yes, gradually: start with the gentle tummy and pelvic floor exercises the NHS describes, and avoid sit-ups and planks to start with. If a gap down the middle is still obvious at 8 weeks, see a GP; our diastasis recti and postpartum guides take it from there.
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.
