Lower Back Pain When Doing Leg Raises: Causes and Fixes

When to get help first

Exercise is for pain that has been checked or is clearly mild and settling.

Get urgent medical help if

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.
Call 999 or go to A&E: back pain with chest pain, or back pain that started after a serious accident, such as a car crash.
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.
Same day (NHS 111): back pain after a new, significant injury in the last 7 days, such as a fall from a height (off a box, a bar or rings) or a direct blow to the back.
Call 999 or go to A&E now if you have a femoral hernia (a small lump at the top of your thigh, in your groin) and very bad tummy pain, you feel sick or you're being sick, you cannot fart or poo, you have a high temperature or you feel hot, cold or shivery, or you've suddenly become confused. Do not drive to A&E. With any other hernia and pain in or around it, a bloated tummy, feeling or being sick, vomiting blood or vomit that looks like coffee grounds, constipation, a high temperature or feeling hot, cold or shivery, or sudden confusion, get help from NHS 111.
Call 999 or go to A&E: tummy pain that started suddenly and is severe, you're vomiting blood or your vomit looks green or like ground coffee, there's a lot of blood coming from your bottom or your poo is black and sticky, you cannot pee at all, you cannot poo or fart at all, you have spots or a rash that does not fade when you press it (it may be harder to see on brown or black skin), or you're struggling to breathe. Don't drive yourself.
If you take a blood thinner (an anticoagulant) and notice severe bruising or bleeding, get medical help immediately: call 111 or go to A&E. A painful lump in the tummy wall that grows after a cough, a strain or a knock can be bleeding into the muscle (a rectus sheath haematoma), which is more likely on blood thinners and easily mistaken for a strain.
Call 999: sudden, severe pain in the tummy or back, which can come with breathlessness, pale or grey skin, or collapse. It can be a burst abdominal aortic aneurysm, most common in men aged 65 or over and in people who smoke or used to smoke.
Same day: leg weakness that is getting worse.
Same day (urgent GP appointment or NHS 111): new difficulty lifting the front of your foot or toes (foot drop), or a foot that slaps down or catches as you walk, especially if it is getting worse. Weakness in both legs, or with numbness around the genitals or bottom or bladder or bowel changes, is the 999 emergency above.
Same day (call NHS 111, or go to A&E if you feel very unwell): after a big or unusual session, such as hundreds of squats, sit-ups, back extensions or burpees, a challenge or a new class, muscle pain, swelling or weakness far worse than the session explains, and dark pee (red, brown, tea or cola coloured), sometimes starting hours or days later. Dark pee isn't always there, so muscles far sorer, more swollen or weaker than the session explains still need the same-day check. It can be rhabdomyolysis, a breakdown of muscle that can harm the kidneys.
Call 999: sudden, severe pain in a swollen, tight muscle.
Same day: you have or have had cancer, and new back pain that is severe and doesn't let up, is getting steadily worse, is worse at night and disturbs your sleep, is worse when you cough, sneeze or strain, or comes with tenderness over the spine. Contact your cancer team or GP urgently. With cancer, new weakness, difficulty walking, numbness or bladder or bowel problems are an emergency.

See a doctor or physiotherapist if

Back pain that hasn't improved after a few weeks of looking after it at home, stops you doing day-to-day activities, worries you, or you're struggling to cope.
Pain that doesn't improve with rest or is worse at night, or pain that is worse when you sneeze, cough or poo.
Unexplained weight loss, or a lump, swelling or change in the shape of your back.
Pain, tingling or numbness spreading below the knee that isn't settling after a few weeks, is getting worse or stops your normal activities: see a GP.
A lump in the groin, upper thigh or tummy, especially one that appears when you cough or strain and goes when you lie down: see a GP, as it may be a true hernia. A femoral hernia (a small lump at the top of the thigh, mainly in women over 50, though it can happen to anyone) needs treating in hospital.
A ridge or doming down the middle of your tummy when you strain, during or after pregnancy: see our diastasis recti guide, and ask about a pelvic health physiotherapist.
A strain that is getting worse, or isn't feeling better after looking after it yourself: see a GP or physiotherapist. In many areas you can refer yourself to physiotherapy.
A teenager or young adult whose low back pain is worse arching backwards and hasn't settled after a couple of weeks: stop the lifts that arch the back and get it checked by a GP or a sports medicine doctor or physiotherapist. It can be a stress fracture of the spine (spondylolysis), which usually does well without surgery when it's found.
Sudden new back pain after a minor fall, lift, cough or sneeze, from 50 or past the menopause, or if you take long-term steroid tablets; or height loss, a curved spine or a change in posture: see a GP. It can be a spinal fracture.
Back pain that started before 45 and has lasted more than 3 months, especially if it started before 35, wakes you in the second half of the night, comes with buttock pain, gets better with movement or within 48 hours of anti-inflammatory painkillers, or you have or have had arthritis, pain where a tendon attaches to bone (enthesitis) or psoriasis, or a parent, brother, sister or child with spondyloarthritis. These can point to inflammatory back pain (axial spondyloarthritis, such as ankylosing spondylitis). The National Institute for Health and Care Excellence (NICE) asks GPs to refer people with 4 or more of these 9 features to a rheumatologist, and to do a blood test for the HLA-B27 gene marker if exactly 3 are present, referring if it is positive.

Where does it hurt?

Location narrows the likely causes; it does not diagnose.

An ache across the lower back as the legs lower and the back arches, easing when you bend your knees or stop lowering so far

Usually ordinary low back pain, brought on by the arch. It is the commonest kind and usually settles within weeks.

Read: Back pain →A sudden catch or sharp pain on one side during a rep, sometimes with the muscles locking up

Usually a pulled back muscle or a back spasm, which settles over days to weeks.

Read: Back spasm and pulled back muscle →A dull ache across the lower back or tummy the day after a new or harder ab session

Muscle soreness.

Read: Back pain after a workout →The front of the hip or groin as the leg lifts, or cramping there

The hip flexors, the muscles at the front of the hip that lift the legs.

Read: Hip flexor pain →A deep pinch in the groin as the knees come to the chest

Possibly the hip joint itself.

Read: Hip pain lifting your leg →A sudden sharp pain in one spot of the tummy wall, sore to tense, twist, cough or sit up

Usually a strained tummy muscle.

Read: Abdominal strain →A lump or bulge in the groin, at the top of the thigh or near the belly button, bigger when you strain or cough and smaller lying down

A possible hernia: see a GP, and read the warning signs for when it is urgent.

Read: Groin pain →Low in the tummy just above the groin crease, worse with sit-ups, coughing or sneezing, with no lump

Often inguinal-related groin pain, sometimes called a sports hernia.

Read: Sports hernia →

A ridge or doming down the middle of the tummy when you lift your legs or head, during or after pregnancy

A separation of the six-pack muscle (diastasis recti): ease off that move, and ask about a pelvic health physiotherapist.

Down one leg past the knee, with tingling, numbness or weakness

Sciatica, often from a disc.

Read: Sciatica →A scan report says bulging or herniated disc

Disc changes are common in people without back pain.

Read: Herniated or bulging disc →A teenager or young athlete whose back hurts more arching backwards, building over weeks

Possibly a stress fracture of the spine: get it checked, as the warning signs say.

Read: Spondylolisthesis →Right at the base of the spine, worse sitting or rolling onto it

Tailbone pain, often from a hard floor.

Read: Tailbone pain →Lifting the leg hurts in daily life (in bed, getting dressed, the car), or the leg is weak and hard to lift

Not the exercise: a weak leg is a nerve sign (see the warning signs); otherwise it's usually the back or the hip.

Read: Hip pain lifting your leg →

Pain spreading from the tummy to the back, sudden severe tummy pain, or pain with a fever

Not a leg raise problem: see the warning signs.

Understand it

What a leg raise asks of the back, and what no study has countedEmerging evidence

Lying on your back, the hip flexors (the iliopsoas, part of which, the psoas, attaches to the lower spine) lift the legs, and the tummy muscles hold the pelvis so the lower back doesn't arch. In 6 men, lifting both legs needed the tummy muscles and lifting one didn't. Straight legs are a long, heavy lever: across 9 studies of 109 healthy adults, the iliopsoas worked hardest around 60 degrees of hip bend and more with straight legs and both legs together, and in 9 men its activity kept rising to the top of a straight-leg raise.

As both straight legs lowered from vertical in 17 adults, the pelvis started to tip forward after only 3.6 degrees of lowering on average, whether or not they tried to stop it, and more as the legs went lower. In 16 men holding their legs just off the floor, a tipped-forward pelvis gave the six-pack less to do. Hanging from a bar adds the whole weight of the legs: in 14 men, the hanging straight-leg raise was the hardest tummy exercise tested, at about 3,000 newtons (N) of compression on the spine.

No study has tested leg raises in people with back pain or counted back pain caused by them. The evidence is small lab studies in healthy, mostly young men, one measurement inside the body in 5 older people with a spinal implant, trials of exercise for back pain in general, and NHS pages. People with an irritable lower back, a recent strain, or a back that dislikes arching are the ones it usually bothers, as are people who jump from crunches to hanging straight-leg raises (our reading).

Sources 1, 2, 3, 4, 5, 6

The usual cause: ordinary back pain, brought on by the archEmerging evidence

An ache across the lower back as the legs lower, easing when you bend your knees or stop lowering so far, is usually ordinary low back pain, the commonest kind, which the NHS says "usually improves within a few weeks". The point where it hurts is usually where the lever is longest and the pelvis tips furthest, close to the floor. Stop lowering where your back starts to lift.

Sources 3, 7, 8

"Are leg raises bad for my back?" What the load measurements showEmerging evidence

The only measurement of a lying leg raise comes from 5 people aged 62 to 71 with a spinal implant that recorded the load on it. Lifting one straight leg added about 10 N on average (nearly 100 N in one person), lifting both straight legs added nearly 220 N, and lifting the pelvis in a bridge about 250 N: about the same as a bridge or a bird dog. That is a tiny study in older people after spinal surgery, so it shows leg raises aren't unusually heavy on the spine, not that they are safe for every back.

The psoas squeezes the lower spine together as it lifts the legs. One modelling study says it doesn't put large shearing forces on the spine except at the very bottom and "cannot have major affects to 'control lordosis'"; another says that at full effort it puts large compression and shear on the spine. Sit-ups worked the psoas harder (15% to 35% of maximum) than curl-ups (under 10%) in 8 people.

Sources 9, 5, 10, 11, 12

Hanging against lying raisesEmerging evidence

Hanging straight-leg raises load the spine heavily (about 3,000 N) and need the pelvis to curl, which some backs dislike. In 21 adults, hanging knee raises with arm straps were among the hardest tummy exercises tested, with low back-muscle activity. Lying raises arch the back as the legs lower, and lowering both legs with the pelvis held tilted back worked the tummy muscles harder than a curl in 15 men. No study compares the versions in people with pain.

Sources 5, 13, 3, 14

The tummy wall: a strain, a hernia or a separationEmerging evidence

A sudden sharp pain in one spot of the tummy wall, sore to tense, cough or sit up, is usually a strained six-pack muscle: 21 tennis players with one returned to sport in 4.5 weeks on average (2 to 8), and 5 handball players in 16 to 22 days.

A lump that "may get bigger when you cough, sneeze or cry, and get smaller when you lie down" can be a hernia, which the NHS says to show a GP. Most hernias aren't urgent. A femoral hernia (a small lump at the top of the thigh) with very bad tummy pain, sickness or no wind or poo is a 999 or A&E emergency, and any other hernia with pain and those signs needs help from NHS 111, as the warning signs say.

A ridge or doming down the middle of the tummy during or after pregnancy is a separation of the six-pack muscle (diastasis recti): 60% of 300 first-time mothers had one at 6 weeks and 33% at a year. The NHS says to contact your GP if the gap is still obvious 8 weeks after the birth.

Sources 15, 16, 17, 18, 19, 20

Nerves, discs and "the leg lift test"Emerging evidence

Pain, tingling or numbness spreading below the knee is sciatica, often from a disc; the NHS says leg pain is usually worse than back pain, and "even if moving hurts, it's not harmful". No study has measured disc pressure in a leg raise; in one volunteer, disc pressure rose with muscle effort and loaded bending.

The "straight leg raise test" or "leg lift test" people search for is a doctor's test for an irritated nerve: they lift your straight leg for you to see if it brings on leg pain. It isn't the exercise. A leg that is weak or hard to lift is a nerve sign that needs checking, urgently if both legs or the bladder or bowels are affected.

Sources 21, 22, 7

What a scan shows, and what it doesn'tStrong evidence

The National Institute for Health and Care Excellence (NICE) says "Do not routinely offer imaging in a non-specialist setting" for back pain. In 3,110 people without back pain, disc wear on scans rose from 37% at 20 to 96% at 80, and disc bulges from 30% to 84%, so a report of a bulging disc doesn't explain pain on its own. The warning signs need urgent assessment instead, and a lump that may be a hernia needs a GP to examine it.

Sources 23, 24

How it usually goesStrong evidence

No study follows back pain from leg raises. Across 33 groups of people with new back pain (11,166 people), average pain fell from 52 out of 100 at the start to 23 at 6 weeks, 12 at 26 weeks and 6 at a year; in back pain that had already lasted, it fell more slowly, from 51 to 23 at a year. The NHS says sciatica "usually gets better in a few weeks to a few months", and tummy muscle strains in athletes took 2 to 8 weeks. No one can promise a date.

Sources 8, 7, 21, 15, 16

What helps, and how strong the evidence is

Exercise helps back pain, but "core" exercise isn't specialStrong evidence

Across 249 trials, exercise cut long-lasting back pain by about 15 points out of 100 against no treatment, usual care or a placebo. Motor control ("core") exercise beat minimal treatment but was no better than other exercise (29 trials, 2,431 people), and Pilates eased pain in the short term against minimal treatment (10 trials, 510 people, low quality); in 296 people, Pilates twice a week did better than once. NICE suggests a group exercise programme of any type, and a US physical therapy guideline lists trunk strengthening among the exercise types to use. No trial has tested leg raises for back pain, so this plan uses back pain trials' exercises and doses and brings leg raises back last.

Sources 25, 26, 27, 28, 23, 29

Leg raises don't single out the "lower abs"Mixed evidence

In 11 lean adults, the upper and lower parts of the six-pack worked alike in trunk exercises including leg raises, and in 8 adults curl-ups worked both parts harder than leg lowering. On ultrasound in 15 young adults, a crunch thickened the muscle 36% more than a leg raise, though the lowest part changed most in the leg raise; in 20 students a lying leg raise drew less upper six-pack and side-muscle activity than a sit-up. The parts act "like a functional unit", so you can shift the emphasis a little, not isolate the lower abs.

Sources 30, 31, 32, 33, 34

A weak core and tight hip flexors: what the studies showEmerging evidence

A review of 26 cohort studies found "strong evidence that there is no relationship between trunk muscle endurance and the risk of low back pain", and across 12 cohorts (5,459 people) tummy muscle strength didn't predict new back pain, though in one cohort of 1,789 workers, weaker back-muscle endurance did raise the risk.

In 600 adults, hip flexor length wasn't linked with back pain, but weaker hip flexors were. In 118 adults, back pain went with less hip extension (4 against 8 degrees), but not once body weight was taken into account; the usual test of hip flexor tightness isn't valid unless the pelvis is held still; and the only stretching study we found was a single session in 20 people. So strength comes before stretching, and tight hip flexors haven't been shown to cause back pain.

Sources 35, 36, 37, 38, 39, 40, 41

Pressing the back flat into the floorEmerging evidence

No trial compares pinning the back flat with a neutral spine for back pain. In 16 men, a neutral pelvis worked the six-pack as well as a tilted-back one, and a tipped-forward pelvis worked it less; across 8 studies, people with back pain had the same lower back curve as people without. NHS inform and a pelvic health physiotherapy booklet teach a gentle flattening tilt as an exercise, while another teaches a neutral spine "neither too tucked nor too arched". The practical rule is ours: lower only as far as your back stays still.

Sources 4, 42, 43, 44, 45

After a baby, and with a separationEmerging evidence

Curl-ups for 12 weeks neither widened nor narrowed the gap and built strength in 70 women after birth, the evidence for any programme is very low quality (7 trials, 381 women), and the only leg raise trial (40 women, small and poorly reported) found no harm. The NHS says avoid sit-ups, planks and high-impact exercise "to start with", and a pelvic health physiotherapy booklet's knee fold says "Your tummy should not bulge upwards or dome". Nothing supports a lasting ban on leg raises; build up to them, and ease off a move that makes the middle of the tummy dome.

Sources 19, 46, 47, 48, 20, 45

Hernias and lifting: the guidance differsMixed evidence

After a groin hernia repair, the NHS says no heavy lifting or strenuous activity for at least 4 to 6 weeks, while an international guideline says "A period of rest or a lifting restriction is not necessary". In 30 women, crunches raised the pressure inside the tummy no more than getting out of a chair. No source names when leg raises can come back after a repair, so follow your surgical team.

Sources 49, 50, 51

How much pain is OK while you exercise?

Up to about 5 out of 10, no worse the next morning, never into a legEmerging evidence

This guide uses the back hub's rule, as our other back movement guides do. Some discomfort during exercise is fine, and it does not mean you are doing damage. Aim for pain you would call mild to moderate, no more than about 5 out of 10. It should settle within an hour or so, and your back should be no worse the next morning. If it is worse, do less next time (fewer reps, a smaller range, a lighter load), not nothing. Leg symptoms are the exception: stop or shrink any movement that sends pain, pins and needles or numbness further down a leg. The 5 out of 10 figure matches NHS inform's back exercise bands (0 to 3 minimal, 4 to 5 acceptable, 6 to 10 excessive, and no worse the morning after); an NHS trust's back leaflets allow discomfort that eases within 2 hours; the NHS back pain page is stricter, saying stop if your pain gets worse and see a GP. In long-lasting pain, exercise into some pain did no worse than pain-free exercise (7 trials, 385 people).

For leg raises (our suggestion, built on the same rule): use the lever (bent knees, one leg, straight legs), the range (how low the legs go) and the version (lying, captain's chair, hanging) where the last reps stay at 5 out of 10 or less and your back is no worse the next morning. If it isn't, go back one step, not to nothing.

Three things aren't pain-rule questions: pain, tingling or numbness spreading down a leg; a sharp pain in one spot of the tummy wall or a bulge there (our abdominal strain guide keeps a lower ceiling of 3 to 4 out of 10 for a recent strain); and a ridge or doming down the middle of the tummy after pregnancy.

Sources 43, 52, 7, 53

The exercise plan: 3 stages

Start at the first stage. Each move opens a full guide with a 3D demo.

Stage 1

Keep moving, take the long lever out

About the first 2 weeks: daily walking, and tummy work with one bent leg at a time and the back still. No straight double leg raises, hanging raises, flutter kicks or V-ups for now. With a diagnosed condition (sciatica or a disc, a tummy strain, a hernia or a repair, a separation after pregnancy, a hip flexor strain), that guide's plan comes first; after surgery, the surgical team's plan does.

Treadmill walking demonstrated on the 3D figure

3D demoTreadmill walkingBeginner · Cardio machine

5 to 10 min, several times a day · As in our back pain guide (editorial); outdoors is just as good. The NHS says stay active

Harder: Treadmill jogging

3D demoKnee foldBeginner · No equipment

2 sets of 5 to 10 each side, every other day · The move page's dose (a pelvic health physiotherapy booklet's). Keep the pelvis level; the tummy shouldn't dome

Easier: Supine heel slide · Harder: Dead bug heel taps

Supine heel slide demonstrated on the 3D figure

3D demoSupine heel slideBeginner · No equipment

10 slow repetitions each side, once or twice a day · The move page's dose, an editorial starting point

Harder: Hip windshield wipers

Dead bug heel taps demonstrated on the 3D figure

3D demoDead bug heel tapsBeginner · No equipment

2 sets of 6 to 8 each side · As in our back pain guide (editorial). Lower each foot only as far as the back stays still

Easier: Bent-knee fall-out · Harder: Forearm plank

Glute bridge demonstrated on the 3D figure

3D demoGlute bridgeBeginner · No equipment

2 to 3 sets of 10 · As in our back pain guide (editorial); an NHS trust's back leaflet holds the bridge for 2 seconds, 10 times

Easier: Pelvic tilt into bridge · Harder: Single-leg glute bridge

3D demoCat-cowBeginner · No equipment

8 slow waves, small range · The move page's dose. If bending forward eases your back, hugging your knees to your chest is an alternative

Harder: Half lord of the fishes (Ardha Matsyendrasana)

Move on when: You can walk for 15 to 20 minutes and get through normal daily tasks, heel taps pass the pain rule with the back still, and your back is no worse the next morning (as in our back pain guide's first stage).

Follow along: a timer, a cue and the next move, one step at a time.

Stage 2

Hold the trunk still while the legs move

About weeks 2 to 6, 2 or 3 days a week, plus walking: the tummy muscles holding the pelvis against a growing lever, and a small, controlled curl of the pelvis.

3D demoDead bugBeginner · No equipment

2 sets of 6 to 8 each side · As in our back pain guide (editorial)

Easier: Dead bug heel taps · Harder: Forearm plank

3D demoBird dogBeginner · No equipment

2 to 3 sets of 6 to 8 each side, 3 to 5 s holds · As in our back pain guide (editorial)

Easier: Bird dog, one limb at a time · Harder: Bear crawl

McGill curl-up demonstrated on the 3D figure

3D demoMcGill curl-upBeginner · No equipment

3 to 5 holds of 8 to 10 s · As in our herniated disc guide (editorial). Skip it if bending forward sends pain down a leg, as the move page says

Harder: Crunch

Knee side plank demonstrated on the 3D figure

3D demoKnee side plankBeginner · No equipment

3 holds of 15 to 20 s each side · As in our back pain guide (editorial)

Harder: Side plank

Reverse crunch demonstrated on the 3D figure

3D demoReverse crunchIntermediate · No equipment

2 to 3 sets of 8 to 12, a small curl · As in our abdominal strain guide, from the tennis players' programme. Ease off if repeated bending flares your back, as the move page says; a mat under the tailbone

Easier: Cross-body crunch · Harder: Captain's chair knee raise

Half-kneeling Pallof press demonstrated on the 3D figure

3D demoHalf-kneeling Pallof pressBeginner · A band + An anchor point

2 to 3 sets of 8 to 10 each side · As in our back pain guide (editorial)

Harder: Pallof press

Move on when: Dead bugs and reverse crunches pass the pain rule with the back still, for a week, and your back is no worse the next morning (editorial).

Follow along: a timer, a cue and the next move, one step at a time.

Stage 3

Back to leg raises: bent knees, then straight, then hanging

From about week 6, often later, 2 or 3 core sessions a week: leg raises back in your training, one step at a time, with the range set by when your back starts to lift, by the written steps below. No study has tested a return to leg raises after back pain, so the order is editorial.

Bent-knee hip raise demonstrated on the 3D figure

3D demoBent-knee hip raiseIntermediate · No equipment

2 to 3 sets of 10 to 15 slow reps, stopping with 2 or 3 reps in reserve · The move page's dose, an editorial starting point. Stop the feet higher if your back lifts, as the move page says

Easier: Lying leg raise on a bench · Harder: Chin-up with a knee raise (gorilla chin)

Bench leg pull-in demonstrated on the 3D figure

3D demoBench leg pull-inIntermediate · A bench or box

2 to 3 sets of 10 to 15 slow reps, stopping with 2 or 3 reps in reserve · The move page's dose, an editorial starting point

Easier: Leg pull-in · Harder: Ab wheel rollout from the knees

Lying leg raise on a bench demonstrated on the 3D figure

3D demoLying leg raise on a benchBeginner · A bench or box

3 sets of 6 to 10 on a bench, lowering over about 3 s, only as far as your lower back stays down · As in our leg raise page (editorial). The pelvis tips early as straight legs lower

Easier: Seated knee tuck on a bench · Harder: Captain's chair knee raise

Captain's chair knee raise demonstrated on the 3D figure

3D demoCaptain's chair knee raiseIntermediate · Other / check instructions

2 to 3 sets of 8 to 12 · As in our hanging leg raise page (editorial). The captain's chair takes grip and swing out

Easier: Reverse crunch · Harder: Hanging straight-leg raise

Hanging knee raise demonstrated on the 3D figure

3D demoHanging knee raiseIntermediate · Pull-up bar

2 sets of 8 to 12 · As in our hanging leg raise page (editorial). Arm straps if your grip fails first; not with a shoulder that slips, as the move page says

Easier: Reverse crunch · Harder: Hanging straight-leg raise

Side plank demonstrated on the 3D figure

3D demoSide plankIntermediate · No equipment

3 holds of 20 to 30 s each side · As in our back pain guide (editorial)

Easier: Knee side plank · Harder: Side plank with leg lift

Move on when: Bench leg raises and hanging knee raises pass the pain rule for 2 weeks: then add one change at a time by the written steps below. If a session flares it, go back a stage for a few days, not to nothing (editorial).

Follow along: a timer, a cue and the next move, one step at a time.

What to change for now

Your leg raises for now (written steps)

Our 3D figure can't show all of these. They come from lab studies, the NHS and our leg raise pages; where a step is our suggestion, it says so. No trial has tested a change to the leg raise for back pain.

1. Bend your knees: a shorter lever means less pull from the hip flexors and less arch.
2. One leg at a time: one leg needs the tummy muscles less, and added almost no load on the spine in the implant study.
3. Lower only as far as your lower back stays down, and don't force it flat. The pelvis tips early as straight legs lower.
4. Swap hanging straight-leg raises and toes to bar for knee raises on a captain's chair, or with arm straps.
5. Slow down: about 3 seconds down, with no swinging or kipping (our suggestion).
6. Breathe out as the legs lift and don't hold your breath, especially with a hernia or after tummy surgery (our leg raise page).
7. A mat or folded towel under the tailbone on a hard floor (our suggestion).
8. Keep moving: the NHS says "stay active and try to continue with your daily activities" and don't stay in bed for long periods; advice to stay active did slightly better than bed rest.

Sources 1, 2, 9, 3, 4, 5, 13, 7, 54

After a baby, a hernia or tummy surgery

After a baby, start with the NHS's gentle tummy exercises (a side-lying draw-in held for a count of 10, up to 10 times) and a pelvic health physiotherapy booklet's pelvic tilt, then knee folds and heel slides, and bring leg raises back once a move no longer makes the middle of your tummy dome. Later in pregnancy, avoid lying flat on your back for long, as our leg raise page says.

With a hernia, or after a repair or other tummy surgery, follow your surgical team. The NHS says no heavy lifting or strenuous activity for at least 4 to 6 weeks after a groin repair, and our hernia page leaves double leg raises out at first after a repair at or near the belly button.

Sources 20, 44, 45, 49

Back to your usual training (written steps)

No study has tested how leg raises come back after back pain, so these steps are our suggestion unless a source is named.

1. Add one thing at a time: more reps, then a longer lever (straighter legs), then lower legs, then hanging.
2. Hanging straight-leg raises last, at 3 sets of 6 to 10 with 90 seconds' rest (our hanging leg raise page), once hanging knee raises pass the pain rule: they load the spine most.
3. Toes to bar, V-ups, flutter and scissor kicks and dragon flags after that, if your training needs them.
4. Keep two days a week of the stage 2 moves. Core exercise isn't better than other exercise for back pain, so keep whatever activity you enjoy, such as walking, Pilates (twice a week did better than once) or the gym.
5. If a session flares it, go back a stage for a few days, not to nothing.

Sources 5, 26, 25, 28

Positions to swap, and why

Habit or position	Why it matters	Instead
Straight double leg raises lowered to the floor	The pelvis tips and the back arches early as straight legs lower.	Bent knees.Try: Bent-knee hip raise
Hanging straight-leg raises and toes to bar	About 3,000 N of compression on the spine, the most of any version measured.	Knee raises on a captain's chair.Try: Captain's chair knee raise
Flutter and scissor kicks held for minutes	A long lever held low (our reading).	Dead bug heel taps.Try: Dead bug heel taps
V-ups and jackknife sit-ups	Long levers and a fast, loaded bend (our reading).	A small reverse crunch.Try: Reverse crunch
Pressing your back into the floor as hard as you can	A neutral pelvis worked the tummy muscles as well as a tilted-back one, and a pelvic health booklet teaches a neutral spine.	Lower only as far as your back stays still.Try: Dead bug
Hands tucked under your bottom to get the legs lower	It lets the legs go further than your trunk can control (our reading).	A shorter range with bent knees.Try: Knee fold
Swinging or kipping hanging raises	Momentum takes the control away, and a fall from the bar needs a same-day check.	The captain's chair.Try: Captain's chair knee raise
Long hip flexor stretches "to release" the back	Hip flexor length wasn't linked with back pain, but weakness was, and no adequately sized stretching trial exists.	Hip flexor strength through range.Try: Leg pull-in
Double leg raises with a hernia or soon after tummy surgery	The move pages' cautions note that UK hospital and stoma leaflets advise against double leg raises at first after tummy surgery, and our hernia page leaves them out at first after a repair at or near the belly button.	The beginner core moves, such as the dead bug, as your surgical team allows.Try: Dead bug
Leg raises that make the middle of your tummy dome after a baby	The NHS says avoid sit-ups and planks to start with, and a pelvic health booklet says the tummy shouldn't bulge upwards or dome.	Knee folds and heel slides first.Try: Knee fold
Leg raises flat on your back later in pregnancy	Lying flat on your back for long is best avoided later in pregnancy (our leg raise page).	Side-lying leg lifts.Try: Side-lying leg raise
Pushing through pain spreading down a leg	It points to a nerve: see the warning signs and our sciatica guide.	Stop, and keep to gentle moves that don't send pain down the leg.Try: Supine heel slide
Bed rest until it stops hurting	Staying active did slightly better than bed rest, and the NHS says don't stay in bed for long periods.	Walking and the stage 1 moves.Try: Treadmill walking

Routines to follow

Lower ab workout: a leg raise ladder from heel taps to bench leg raises

A 15-minute lower ab workout: heel taps, reverse crunches and leg pull-ins, then lying leg raises and the hip lift. It trains your whole six-pack; pick your step.

15 minBeginner11 movesA bench or box

Hanging leg raise progression workout: five steps to strict toes to bar

A 25-minute ladder to hanging leg raises: reverse crunches, the captain's chair, hanging knee and straight-leg raises, then strict toes to the bar.

25 minBeginner10 movesPull-up bar, A step

Beginner core workout

A 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.

15 minBeginner6 movesNo equipment

McGill big 3 core routine

The 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 equipment

Pilates for back pain (gentle routine)

A gentle 15-minute Pilates-based routine for ongoing low back pain, built from neutral-spine moves with options for backs that dislike bending or arching.

15 minBeginner10 movesNo equipment

Diastasis recti workout: a 12-week curl-up programme

A 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 equipment

More moves for this area

Questions people ask

Why does my lower back hurt when I do leg raises?

As your straight legs lower, your pelvis tips forward and your lower back arches, even in people trying to stop it, and the hip flexors pull hardest when the legs are low. A sore back often complains there. Bend your knees, lower less far, or move one leg at a time.

Are leg raises bad for your back?

No study shows that, though the evidence is thin. In the only lying measurement, in 5 older people with a spinal implant, both legs added about as much load as a bridge and one leg almost none; hanging straight-leg raises are the heavy version. With a sore back, shorten the lever and the range rather than ban them.

Should my lower back stay flat on the floor?

It shouldn't arch, but you don't need to pin it flat: a neutral pelvis worked the tummy muscles as well as a tilted-back one in a lab study. Lower your legs only as far as your back stays still.

Are hanging leg raises worse for my back than lying ones?

Hanging straight-leg raises put about 3,000 N of compression on the spine, the most of any version measured. Hanging knee raises with straps are hard on the tummy muscles with low back-muscle activity, so they come before straight legs.

Do leg raises work the lower abs?

They work the whole six-pack muscle and the hip flexors; the upper and lower parts work together, and a crunch works the muscle more overall. You can shift the emphasis a little, not isolate the lower abs.

Are leg raises good for lower back pain?

Exercise helps long-lasting back pain, but core exercise is no better than other exercise, and no trial has tested leg raises for back pain. Pick the version that passes the pain rule, or a different exercise you enjoy.

Is it my hip flexors? Should I stretch them?

Pain or cramping at the front of the hip points to the hip flexors themselves, and our hip flexor guide covers it. Tight hip flexors haven't been shown to cause back pain, and weaker ones were linked with it, so strength comes before stretching.

Could it be a hernia?

A lump in the groin, at the top of the thigh or near the belly button, bigger when you strain and smaller lying down, can be a hernia: see a GP. A femoral hernia (at the top of the thigh) with very bad tummy pain, sickness or no wind or poo is a 999 or A&E emergency. Any other hernia with pain and those signs needs help from NHS 111.

Can I do leg raises after having a baby?

Build up to them: the NHS says avoid sit-ups and planks to start with and begin with gentle tummy exercises. Knee folds and heel slides come first, and a move that makes the middle of your tummy dome is one to ease off for now.

My back hurts when I lift my leg in bed or getting dressed, or I can't lift my leg. Is that the same?

Not quite. Pain lifting the leg in daily life is usually the back or the hip, and our back pain and hip pain when lifting your leg guides cover it. A leg that is weak or hard to lift is a nerve sign that needs checking, urgently if both legs or the bladder or bowels are affected.

Do I need a scan?

Not usually: NICE doesn't routinely offer imaging for back pain, and disc bulges are common in people without pain. The warning signs need urgent assessment instead.

How long will it take, and when should I see a doctor?

Most new back pain eases a lot within 6 weeks, though no one can promise a date. Call 999 for numbness around your genitals or bottom, new bladder or bowel trouble, or weakness in both legs; get a same-day check for back pain with a fever or after a fall from the bar. See a GP if it isn't better after a few weeks; in the US, call 911 where this page says 999.

When to get help first

Get urgent medical help if

See a doctor or physiotherapist if

Where does it hurt?

Understand it

What a leg raise asks of the back, and what no study has countedEmerging evidence

The usual cause: ordinary back pain, brought on by the archEmerging evidence

"Are leg raises bad for my back?" What the load measurements showEmerging evidence

Hanging against lying raisesEmerging evidence

The tummy wall: a strain, a hernia or a separationEmerging evidence

Nerves, discs and "the leg lift test"Emerging evidence

What a scan shows, and what it doesn'tStrong evidence

How it usually goesStrong evidence

What helps, and how strong the evidence is

Exercise helps back pain, but "core" exercise isn't specialStrong evidence

Leg raises don't single out the "lower abs"Mixed evidence

A weak core and tight hip flexors: what the studies showEmerging evidence

Pressing the back flat into the floorEmerging evidence

After a baby, and with a separationEmerging evidence

Hernias and lifting: the guidance differsMixed evidence

How much pain is OK while you exercise?

Up to about 5 out of 10, no worse the next morning, never into a legEmerging evidence

The exercise plan: 3 stages

Keep moving, take the long lever out

Hold the trunk still while the legs move

Back to leg raises: bent knees, then straight, then hanging

What to change for now

Your leg raises for now (written steps)

After a baby, a hernia or tummy surgery

Back to your usual training (written steps)

Positions to swap, and why

Routines to follow

Lower ab workout: a leg raise ladder from heel taps to bench leg raises

Hanging leg raise progression workout: five steps to strict toes to bar

Beginner core workout

McGill big 3 core routine

Pilates for back pain (gentle routine)

Diastasis recti workout: a 12-week curl-up programme

More moves for this area

Questions people ask

Related exercise guides

Other pain guides

Sources