Training guide
Visible abs take two things: a six-pack muscle thick enough to show, and little enough fat over it. Ab exercises build the muscle, but they don't burn the fat on your stomach: in trials, weeks of crunches and other ab moves didn't shrink belly fat or waist size. The fat comes off your whole body, slowly, by eating a little less and moving more.
How lean you'd need to be is different for everyone. Your genes, sex and age change where you store fat, women need more body fat than men, and we found no study that has measured the body fat level at which abs show. So this guide makes no promise of a look or a date, and puts your health first.
It covers the ab muscles, what the trials show, how to train them (2 or 3 times a week is plenty), how to lose fat without losing muscle, how to measure progress, and when to change the plan: in pregnancy, after a birth, with a hernia or with osteoporosis.
Ab exercises make the six-pack muscle stronger and thicker: 12 weeks of curl-ups thickened it in a trial of 70 women. They don't remove the fat over it: 6 weeks of ab exercises on 5 days a week didn't change belly fat in 24 adults, and adding ab training to a diet did no better than the diet alone.
Two or three moves, 2 or 3 hard sets of each, 2 or 3 times a week, adding reps and then weight. That's our editorial starting point: no trial has tested how often or how much to train the abs, so it borrows from trials of other muscles, where training once, twice or three times a week built about the same muscle when the weekly sets matched.
Aim to lose about 0.5 to 1 kg a week at most, as the NHS suggests, keep strength training, and eat enough protein (about 1.6 g per kg of body weight a day). In 24 elite athletes, losing weight more slowly kept more muscle.
We found no study that has measured the body fat level at which abs show. Genes help decide where your body stores fat, women need more body fat than men, and at the same body mass index (BMI) people carry very different amounts of fat round the middle.
Stage-lean abs are temporary, even for competitors: dieting that hard brought falling hormones and low mood, and in women irregular periods. Strong abs are a realistic aim for anyone; very defined ones may not be healthy for you to hold.
After a birth, with a bulge in your groin or tummy, or with osteoporosis, some ab moves need changing. The sections below say how, and when to see a GP.
The rectus abdominis: two straps running from your lower ribs and breastbone to your pubic bone, joined down the middle by a seam of connective tissue. It curls your trunk forward and, with the other tummy muscles, braces it when you lift, cough or strain. Our rectus abdominis guide covers its anatomy.
Bands of tendon-like tissue cross each strap. In 32 cadavers, 30 people had three bands on each side and 2 had four; in 54 cadavers in India, 52 had three, one had four and one had five. The bands form before birth, by about 11 weeks of pregnancy, so the number of "packs" is set by your anatomy, not by training.
In two muscle activity studies, the upper and lower parts of the muscle worked together in every exercise tested, including leg raises and reverse curls. You can't train one end on its own.
The obliques at your sides turn and side-bend your trunk, and the transversus abdominis wraps round your waist underneath them. They don't make the six-pack, but they brace your trunk; our obliques and transversus abdominis guides cover them.
Fat under the skin covers the muscle, and that's the fat that hides abs. Visceral fat sits deeper, around your organs and behind the muscles: it pushes the belly out rather than hiding the lines, and it matters more for your health, as our belly fat guide explains.
When 12 pairs of identical twins were overfed by the same amount, each pair gained fat in similar places, which points to genes. Women need more body fat than men, muscle comes more slowly with age, and the two straps of the six-pack separate in many pregnancies: 60% of 300 first-time mothers had a gap 6 weeks after the birth, and a third still did at 12 months.
Many ab exercise rankings come from EMG (electromyography: electrodes measuring how hard a muscle works), which shows effort in a few reps, not what a muscle builds over months.
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In 24 inactive adults, 7 ab exercises (2 sets of 10, 5 days a week for 6 weeks), with their diet held steady, changed neither body fat, belly fat, waist size nor skinfolds; only ab endurance improved. In 40 women with overweight or obesity, adding 12 weeks of ab training to a diet took off no more belly fat than the diet alone. Across 13 studies of 1,158 people, mostly comparing a trained arm or leg with an untrained one, training a body part didn't reduce the fat over it, and in 104 adults who trained one arm, fat loss on MRI (magnetic resonance imaging) scans spread across both arms.
In 16 men, adding 57 minutes of machine crunches and twists to 27 minutes of running, 4 days a week for 10 weeks, took about 0.7 kg more fat off the trunk than 45 minutes of running alone, with the same total fat loss. The scan couldn't tell visceral fat from fat under the skin, and nearly an hour of ab work 4 days a week isn't a practical plan. In a smaller trial, a circuit with ab moves thinned the fat over the upper belly on ultrasound, but not the fat over the trained triceps.
In 70 women 6 to 12 months after a birth, 12 weeks of head lifts and curl-ups on 5 days a week thickened the six-pack muscle by 0.7 mm and made it stronger, without widening the gap between its two sides. A 4-week curl-up programme enlarged the trunk muscles on MRI scans, and 8 weeks of hard suspended push-ups thickened the six-pack muscle by 27% in 8 men, in a small study with no control group.
In muscle activity studies of 21 and 18 adults, ab wheel and Swiss ball rollouts and pikes, hanging knee raises with arm straps and a reverse crunch on an incline drew the most six-pack activity; the crunch and sit-up drew less. These studies measure effort in a few reps, not growth.
Across 17 studies, heavy free-weight lifts such as squats and deadlifts worked the deep back and trunk muscles at least as hard as core exercises. But no trial has shown that they grow the six-pack muscle; direct ab training has.
In 25 studies of other muscles, training a muscle once, twice or three times a week built about the same muscle when the weekly sets were matched, and the latest dose meta-analysis agreed. No trial has tested how often, or how much, to train the abs, so the dose below is our starting point.
Elite athletes losing about 0.7% of their body weight a week gained lean mass (2.1%), while those losing 1.4% a week didn't, for the same total loss. Guidance for bodybuilders suggests 0.5 to 1% a week, and in pooled trials, eating about 500 calories a day below your needs stopped lean-mass gains, though strength still rose.
In 49 trials, extra protein stopped adding muscle at about 1.6 g per kg of body weight a day. The International Society of Sports Nutrition suggests 2.3 to 3.1 g per kg may help lean, trained people keep muscle while dieting hard. In 40 young men in a big calorie deficit with intense training, 2.4 g per kg gained 1.2 kg of lean mass while losing 4.8 kg of fat in 4 weeks.
One natural bodybuilder dieting for a contest went from 14.8% to 4.5% body fat; his testosterone fell to about a quarter, his resting heart rate to 27 beats a minute and his mood worsened, all recovering over 6 months. In 27 female fitness competitors who dieted for 4 months, hormones fell and periods became irregular, mostly recovering in 3 to 4 months. Sports judged on looks raise the risk of eating and body-image problems, and training hard on too little food harms health in women and men.
A curl (a crunch, curl-up or cable crunch), a leg raise (a reverse crunch or hanging knee raise), a rollout or plank, and a side plank or carry for the obliques. Two or three of them in a session is plenty.
Our editorial starting point: 2 or 3 moves, 2 or 3 hard sets of each, on 2 or 3 days a week, which comes to about 6 to 12 hard ab sets a week. No trial has tested ab-specific frequency or volume; the dose borrows from trials of other muscles, where 10 or more sets a week built more muscle and frequency mattered little once the sets were matched.
Sets of about 8 to 20, stopping 1 to 3 reps short of failure, with the last set of a small move allowed to get within 0 to 2, as our plans' notes say. In your first two weeks, keep 3 or 4 reps to spare. Light and heavy loads built similar muscle when sets were hard, and going to failure wasn't needed.
When every set reaches the top of its range, move to a harder version or add a little weight, as our plans' double progression does. Cable crunches and weighted crunches make small weight steps easy.
Keep crunches, sit-ups and other bending moves to about 60 reps a session: that's the ceiling one expert review suggests, untested, and our sit-ups guide and crunch workout keep to it. Make the move harder rather than doing more.
Health guidelines ask for strength work for all your major muscles, your abdomen included, on at least 2 days a week, plus 150 minutes of moderate activity. Our full-body plans fit ab work into a complete week.
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The NHS suggests losing 0.5 to 1 kg (1 to 2 lb) a week when you're losing weight. If you're already lean, about 0.5 to 1% of your body weight a week keeps more muscle, from guidance for bodybuilders and a trial in athletes.
Our calories per day calculator uses the NHS's figure of about 600 calories a day below your needs, and never below 1,200 a day. If you also want to build muscle, keep the cut smaller: a deficit of about 500 calories a day stopped lean-mass gains in pooled trials.
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About 1.6 g per kg of body weight a day suits most people; lean, trained people dieting hard may keep more muscle with 2.3 to 3.1 g per kg. Food covers it for most people, and our protein calculator works out your number.
It's possible, especially if you're new to lifting or have fat to lose, with plenty of protein and a moderate deficit. Strength training on its own also trimmed body fat by about 1.5 percentage points across 58 studies.
Aerobic activity, such as brisk walking, takes fat off your whole body, your belly included: each extra 30 minutes a week trimmed the waist a little more in 116 trials. Our belly fat guide covers how much, and what sleep and alcohol do.
Nobody can give you a date. At the NHS's 0.5 to 1 kg a week, losing 5 kg takes roughly 5 to 10 weeks if everything goes to plan (our arithmetic), and weight loss usually slows as you go.
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We found no study that has measured the body fat level at which abs show. The figures online, about 10% for men and 14 to 22% for women, are trainers' estimates from photos, not evidence. In 27 female fitness competitors, 6 dipped below 10% body fat on stage, and none stayed there after their recovery.
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Ab endurance rises within weeks: after 6 weeks of training, one group managed about 15 more curl-ups on a test than a group that didn't train. The muscle itself thickened by 0.7 mm in 12 weeks in the curl-up trial.
Measure your waist every 2 to 4 weeks at the same time of day, midway between your lowest rib and the top of your hip bone, breathing out naturally. Take photos in the same light and log your reps and weights. Bathroom body-fat scales were kilos of fat out against a scan, and NICE (the National Institute for Health and Care Excellence) says not to use them instead of BMI.
Pick one curl, one leg raise, and one rollout or plank, plus a side plank or carry for your obliques. Our sit-ups, plank, side plank and Russian twist guides cover the technique for each.
3D demoCrunchBeginner · No equipment
3D demoMcGill curl-upBeginner · No equipment
3D demoReverse crunchIntermediate · No equipment
3D demoHanging knee raiseIntermediate · Pull-up bar
3D demoAb wheel rollout from the kneesAdvanced · An ab wheel
3D demoKneeling cable crunchIntermediate · A cable machine
3D demoForearm plankIntermediate · No equipment
3D demoSide plankIntermediate · No equipment
3D demoDead bugBeginner · No equipment
3D demoHalf-kneeling Pallof pressBeginner · A band + An anchor point
3D demoRussian twist with a weightIntermediate · Medicine ball
3D demoSuitcase carryIntermediate · A dumbbell + A kettlebellCurls: crunches at 2 or 3 sets of 12 to 20, moving on when every set reaches 20 (our sit-ups guide), then a weighted or cable crunch. Leg raises: reverse crunches, the captain's chair, hanging knee raises at 2 sets of 8 to 12 (our lower body gym workout), then straight-leg raises at 3 sets of 6 to 10 (our advanced core workout). Planks of 20 to 45 seconds, then rollouts from the knees at 3 sets of 6 to 10 (our plank guide). Side planks on your knees for 15 to 30 seconds, then on your feet, then with a leg lift (our side plank guide).
3D demoMcGill curl-upBeginner · No equipment3D demoCrunchBeginner · No equipment
3D demoWeighted crunchIntermediate · Medicine ball3D demoReverse crunchIntermediate · No equipment
3D demoCaptain's chair knee raiseIntermediate · Other / check instructions3D demoHanging knee raiseIntermediate · Pull-up bar
3D demoHanging straight-leg raiseAdvanced · Pull-up bar
3D demoKnee plankBeginner · No equipment3D demoAb wheel rollout from the kneesAdvanced · An ab wheel
3D demoStanding ab wheel rolloutExpert · An ab wheel
3D demoKnee side plankBeginner · No equipment
3D demoSide plank with leg liftAdvanced · No equipmentNew: the gym ab workout uses moves you can load and keeps to about 60 bending reps. The beginner core workout and McGill big 3 suit a back that dislikes bending, and the diastasis recti workout follows the curl-up trial for after a birth.
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 barAn intermediate ab workout with no equipment: planks, side planks, reverse crunches, hollow holds and mountain climbers.
20 minIntermediate7 movesNo equipmentA 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.
15 minBeginner6 movesNo equipmentA 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 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 pointHard 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 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 equipmentThe 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 12-minute tummy routine copied from a trial in women with diastasis recti: head lifts, curl-ups and twisted curl-ups, 5 days a week for 12 weeks.
12 minBeginner5 movesNo equipmentA full-body plan keeps the rest of you training; the weight-loss plan covers the fat-loss side, and the plank challenge builds your holds over 30 days.
A beginner gym plan: three full-body sessions a week, alternating workouts A and B, with sets, reps, rest and an 8-week progression.
3 training days45 minBeginner3 days a weekThree full-body home workouts a week with dumbbells or no equipment at all, plus walks and an 8-week plan to keep progressing.
3 training days35 minBeginner5 days a weekA 12-week workout plan for weight loss: three strength days, two cardio days and daily steps, building to 200 minutes a week, with honest results.
3 training days45 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 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.
The UK consensus on osteoporosis says movements with sustained, repeated or end-range forward bending should be modified or avoided, and reports spinal fractures with sit-ups. Train your trunk with dead bugs, bird dogs, planks, side planks and carries instead, as our osteoporosis guide sets out.
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If bending flares your back, use the McGill curl-up and side plank, shorten your rollouts, and see our back pain guide. Our 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.
If you think you have a hernia, see a GP. You can usually keep exercising, but stop any move that makes it hurt or bulge, as our hernia guide explains. After tummy surgery or with a stoma, build up through gentler core work first, and stop if you notice bulging around a scar or stoma.
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During any exercise, stop and call 999 for chest pain or pressure, unusual breathlessness, dizziness or fainting, as our plans advise. With back pain, call 999 for numbness around your genitals or bottom, new problems controlling your bladder or bowels, or pain, tingling or weakness in both legs, as our back pain guide explains.
If you have a hernia and pain in or around it, a bloated tummy, you feel sick or are being sick, you're vomiting blood, you're constipated, you have a high temperature, or you've suddenly become confused. In the US, contact your doctor or urgent care.
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If you think you have a hernia: a bulge or lump in your groin, upper thigh or tummy that may get bigger when you cough, sneeze or cry and smaller when you lie down. And if the gap down the middle of your tummy is still obvious 8 weeks after a birth: your GP can refer you to a physiotherapist.
Anyone can get an eating disorder, though teenagers and young adults are mostly affected. The NHS lists spending a lot of time worrying about your weight and body shape, eating very little food, exercising too much, and having very strict habits or routines around food among the signs, and says to see a GP as soon as you can. Beat adds exercising in secret, rigid or punishing routines, exercising to make up for eating or because of how you feel about your body, exercising when ill or injured, and feeling guilty or anxious when you can't exercise. In men it can show as a drive to be more muscular.
If you're worried, Beat's helpline in England is 0808 801 0677, and our eating disorders guide has the numbers for Scotland, Wales, Northern Ireland and the US. Worrying a lot about one part of your body, and comparing your looks with other people's, can also be body dysmorphic disorder, which a GP can help with.
Six weeks of ab exercises on 5 days a week didn't change belly fat in 24 adults, and adding ab training to a diet did no better than the diet alone. Across 13 studies, training a body part didn't reduce the fat over it. Crunches strengthen the muscle under the fat.
With weekly sets matched, training a muscle once, twice or three times a week built about the same muscle in 25 studies. Two or three ab sessions a week is plenty.
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Both ends of the six-pack muscle worked together in every exercise tested in two muscle activity studies. It's one muscle.
The number of packs is set by bands across the muscle that form before birth, and the body fat needed to show them may not be healthy for everyone to hold, especially women.
They work the deep trunk muscles hard, but no trial has shown they grow the six-pack muscle. Direct ab training has.
Contest leanness came with falling hormones, a very low heart rate and worse mood in a male bodybuilder, and with falling hormones and irregular periods in female competitors. It's a temporary state, even for them.
Do two things at once: build the six-pack muscle with hard ab sets 2 or 3 times a week, and slowly lose the fat that covers it by eating a little less and moving more. Ab exercises alone don't remove belly fat. Keep training your whole body, eat enough protein, and give it months.
It depends almost entirely on how much fat you have to lose, so nobody can give you a date. At the NHS's aim of 0.5 to 1 kg a week, losing 5 kg takes roughly 5 to 10 weeks if all goes to plan, and loss usually slows. The muscle itself thickens slowly: 0.7 mm in 12 weeks in one trial.
We found no study that has measured it. The figures online, about 10% for men and 14 to 22% for women, are trainers' estimates from photos, and home body fat readings are several points out anyway. How lean you'd need to be depends on where your body stores fat and how thick your ab muscles are.
Only if you already have very little fat over them. Fat comes off at about 0.5 to 1 kg a week at best, and an ab routine doesn't speed up fat loss from your belly. A month is long enough to get stronger and see a smaller waist.
Partly. The number of packs depends on the tendon bands across the muscle, which form before birth: most people have three on each side, and a few have four or five. Where you store fat is partly genetic too: identical twins overfed by the same amount gained fat in similar places, especially deep in the belly.
Two or three times a week is plenty. No trial has tested ab training frequency itself, but for other muscles, training once, twice or three times a week built about the same muscle when the weekly sets matched. Your abs don't need daily training.
Rollouts, hanging knee raises, reverse crunches and crunches or curl-ups drew the most six-pack activity in muscle activity studies, and side planks and carries suit the obliques. Pick two or three, take your sets close to failure, and add reps, then weight.
No. The six-pack is one muscle, and both ends worked together in every exercise tested in two muscle activity studies.
Women build ab muscle like men, but they need more body fat for hormones, periods and bones, so a stage-lean six-pack may not be healthy to hold. In female fitness competitors dieting for 4 months, hormones fell and periods became irregular. Strong abs are a realistic goal; very defined ones may not be.
Yes, for the muscle: curl-ups, reverse crunches, planks, side planks and hollow holds need only the floor, and sets close to failure build muscle with light loads. Seeing your abs still depends on losing fat. Our ab workout with no equipment is ready to follow.
After a birth, the NHS advises avoiding sit-ups, planks and high-impact exercise to start with and building up from gentle tummy exercises; see a GP if the gap down the middle is still obvious at 8 weeks. If you think you have a hernia, a bulge that may get bigger when you cough, see a GP; you can usually keep exercising, but stop any move that makes it hurt or bulge.
Yes: strength training with a sensible plan suits teenagers, but dieting for visible abs isn't a good idea while you're still growing. Eating disorders mostly affect teenagers and young adults, so focus on sport, strength and enough food; our teenagers' plan shows how.
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.
