Pain guide · Back pain
Lower back pain in swimmers usually comes from repeated arching: butterfly, breaststroke with the head held up, head-up kicking on a board, the dolphin kick and turns all add to it, and dryland weights often bring it on. Swimming is also one of the activities the National Health Service (NHS) suggests for back pain, and in a small 2026 study of adults with back pain, backstroke hurt least and breaststroke most.
So the answer is usually to change how you swim, not to stop: backstroke and front crawl, face-in breaststroke, kicking on your back and open turns, with trunk and hip exercises on land. Numbness around the genitals or bottom, or new problems with your bladder or bowels, needs a 999 call or accident and emergency (A&E), and a teenager whose back hurts arching backwards needs a general practitioner (GP) or sports physiotherapist to check for a stress fracture of the spine. This guide covers those signs, what to change in the pool, how much pain is fine and a three-stage plan with a 3D demo of every move.
Exercise is for pain that has been checked or is clearly mild and settling.
Location narrows the likely causes; it does not diagnose.
Worse in butterfly, breaststroke or head-up kicking and easing out of the water: ordinary low back pain from repeated arching. This guide covers it, and our back pain guide goes further.
Read: Back pain →Low back pain that came on suddenly, lifting in the gym or twisting at the wallWith muscle spasm: a strained muscle or ordinary back pain.
Read: Back spasm and pulled back muscle →A teenager's low back pain that lasts and is worse arching backwardsIn butterfly, breaststroke or push-offs, perhaps stopping them training: a possible stress fracture of the spine (spondylolysis). Get it checked.
Read: Spondylolisthesis →Low back pain worse arching back or twisting, sometimes into the buttock, from mid-lifeOften called facet joint pain; a swimming review calls the butterfly version butterfly back.
Read: Facet joint pain →Pain, tingling or numbness down one leg below the kneeSciatica, often from a disc. Shorten or stop any stroke, kick or turn that sends it further.
Read: Sciatica →A scan report that says bulging or worn discsCommon in swimmers and non-swimmers without pain. Our herniated disc guide explains.
Read: Herniated or bulging disc →Low on one side, by the dimple at the back of the pelvisPossibly the sacroiliac joint.
Read: SI joint pain →The back of the pelvis or the pubic bone in pregnancy or after birthPelvic girdle pain.
Read: Pelvic girdle pain (SPD) →Between the shoulder blades, or the mid back, after long setsUpper back pain. The NHS asks for a GP check for pain between the shoulders.
Read: Upper and mid back pain →Low back pain for more than 3 months, or that keeps coming backLong-lasting back pain.
Read: Chronic low back pain →Often worse in the second half of the night: possibly inflammatory back pain. See the see-a-GP signs.
Butterfly carried 2.5 times the risk of low back pain in 341 elite swimmers. Older surveys, as a review summarises them, put back pain at a third to a half of butterflyers and a quarter to a half of breaststrokers, and in one US college team the neck or back was the second commonest injury site after the shoulder. In 88 masters swimmers, 27% had low back pain lasting more than 10 days in a year. We found no study of people who swim for fitness on their own.
Every stroke holds some arch in the lower back to stay streamlined, and reviews describe the arch as greatest in butterfly and breaststroke and in the undulating dolphin kick, with twisting in front crawl and turns. In college men, the 11 with back pain arched more in the dolphin kick than the 21 without, and had stiffer hip flexors and less hip extension.
In a survey of 285 competitive swimmers, more pool training and hypermobility went with more lumbar injuries. Among the 29 with a past lumbar injury, butterfly (86%), dryland strength training (76%) and turns (72%) were the activities most often reported as painful, and paddles and pull buoys the least (14%).
Reviews say a kickboard held out with the head up raises the arms, shoulders and head and arches the lower back, and a return-to-swim protocol lists a stress fracture of the spine among the reasons not to use one. But in the one survey that looked, the 285 competitive swimmers who used kickboards more had fewer lumbar injuries (about 0.6 times the odds). That survey looked back in time, so it can't show cause, and the reviews' warning is expert opinion.
A stress fracture of the bridge of bone at the back of a vertebra (spondylolysis) is less common in swimmers than in divers but not rare: 11.6% of 687 swimmers across 7 studies, against 35.4% of divers, and 41.7% of athletes with low back pain in pooled case series. In four teenage elite swimmers, three of them breaststrokers or butterflyers, the diagnosis took 2 to 7 months in three, and plain X-rays showed only two of the four cracks.
The NHS says these stress fractures are more common in young athletes and gymnasts. A swimming review advises magnetic resonance imaging (MRI) or computed tomography (CT) when an early crack is suspected, about 6 to 12 weeks of rest with or without a brace, and front crawl or backstroke if butterfly and breaststroke still hurt; our spondylolisthesis guide covers the return to sport.
Disc wear on scans was commoner in elite than recreational swimmers (68% against 29%), mostly in the lowest disc, but it wasn't linked with their back pain or their stroke. Swimmers had higher odds of disc wear than non-athletes in a university study, and three of four studies found more in competitive swimmers, yet 100 elite swimmers and 96 non-sporting adults had similar disc wear and back pain overall.
Disc wear is common in people without pain and rises with age (37% at 20, 96% at 80), and the National Institute for Health and Care Excellence (NICE) says not to image low back pain routinely. A scan is for the warning signs, a young swimmer with a possible stress fracture, or leg symptoms that aren't settling.
The NHS says back pain usually improves within a few weeks but can sometimes last longer or keep coming back. In a swimming trial, disability eased more by 8 weeks with a swimming programme, but the groups had evened out by a year. No study has followed swimmers' back pain, and no one can promise a date.
In 76 adults with long-lasting low back pain, an 8-week individual swimming programme with education, guided by 4 online physiotherapy sessions, beat education alone for disability at 8 weeks (2.5 points on a 24-point scale) but not at a year. Pain fell slightly (0.7 out of 10), an amount that may not matter much, and the swimming group had more minor side effects. Aquatic exercise reduced pain in 8 small trials, and the NHS lists swimming among activities that may help.
But reviews found mostly one-off surveys with no clear pattern linking swimming and back pain either way, and too few trials to judge swimming on its own.
In 30 adults with long-lasting back pain who swam 100 m of each stroke in a random order, backstroke had lower average and worst pain than breaststroke, and front crawl wasn't clearly different from backstroke; the differences were small. Butterfly carried 2.5 times the risk of back pain in elite swimmers and was the commonest trigger in swimmers with a past back injury. Swim England says lifting the head rather than the shoulders to breathe in breaststroke "can lead to back pain".
Across 249 trials, exercise reduced long-lasting low back pain by about 15 points out of 100 against no treatment, usual care or placebo, on moderate-certainty evidence. No type clearly beats another, as our back pain guide explains, so choose what you'll keep doing.
Source 30
A swimming review advises trunk endurance and control more than heavy strength, and another lists the dead bug and the bird dog among its trunk exercises. In one study, swimmers with back pain had stiffer hip flexors and less hip extension, so hip range work makes sense too (our reasoning). This is low-level evidence and expert advice, not tested in swimmers.
For the exercises, this guide uses the back hub's rule. 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 your leg. If leg symptoms move back towards your spine, that is a good sign, even if your back aches a little more for a while.
If pain climbs day after day, or you notice any warning sign, stop and get it checked. The 5 out of 10 figure matches this site's other pain guides and has not been tested in a back pain trial; in trials of long-lasting muscle and joint pain, exercise that allowed some pain did no harm. The NHS says to stop exercises if your pain gets worse and see a GP, which means pain climbing day after day, not the passing discomfort this rule allows.
In the pool (our suggestion): choose the stroke that leaves your back steady or easier, which in a small crossover study was backstroke more often than breaststroke, and shorten or stop any stroke, kick or turn that sends symptoms down a leg.
In the pool, this guide's rule is adapted from one expert commentary written for competitive swimmers coming back after shoulder surgery, so treat it as a sensible guide rather than a tested rule. If the sore area is back to its usual level by the next morning, the next swim can be the same or a little longer.
Soreness that lasts more than an hour after swimming, or into the next day: take a day off swimming, then repeat your last session rather than adding to it. Sore in the warm-up but gone within the first few hundred metres: repeat the same session, and if it comes back during that swim, stop, take 2 days off and come back a little shorter (the protocol cuts 300 yards, about 275 m). Sore in the warm-up and still sore after the first few hundred metres: stop for the day, take 2 days off and come back a little shorter.
Start at the first stage. Each move opens a full guide with a 3D demo.
The first days to about 2 weeks. Stay active and walk; swim only what stays within the pain rule, in backstroke or front crawl, with open turns and kicking on your back or side, and leave out butterfly, head-up kicking and long underwater dolphin kicks. Doses are editorial unless a source is named.
3D demoTreadmill walkingBeginner · Cardio machine10 to 30 min a day, building up · Walking outdoors counts. The NHS lists walking among activities that may ease back pain
Harder: Treadmill jogging
3D demoCat-cowBeginner · No equipment8 waves, slower than feels natural · The move page's dose
3D demoHip windshield wipersBeginner · No equipment10 slow passes side to side, 2 rounds · The move page's dose
Easier: Supine heel slide · Harder: 90/90 switch
3D demoSingle knee-to-chest stretchBeginner · No equipmentHold 20 to 30 s, 2 to 4 times each side · The move page's dose. A gentle forward bend, which many people whose back hurts arching find easing (our note). Leave it out if bending forward sends pain down a leg, as the move page says
Harder: 90/90 hip lift-off
3D demoPelvic tilt into bridgeBeginner · No equipment2 sets of 8 to 10 · As in the back pain when cycling guide
Harder: Glute bridge
Move on when: 20 to 30 minutes of walking feels fine, 20 minutes of backstroke or front crawl leaves your back no worse the next morning, and nothing is spreading down a leg.
About weeks 2 to 6, 2 to 3 days a week, with easy swimming on most other days. A swimming review lists the dead bug and the bird dog among its trunk exercises, and swimmers with back pain had stiffer hip flexors. No type of exercise clearly beats another for back pain, so choose what you'll keep doing. Doses are editorial unless a source is named.
3D demoBird dogBeginner · No equipment2 to 3 sets of 6 to 8 each side · As in the back pain when cycling guide. Reach long rather than high so the back doesn't arch, as the move page says
Easier: Bird dog, one limb at a time · Harder: Bear crawl
3D demoDead bugBeginner · No equipment2 to 3 sets of 6 to 8 each side · As in the back pain when cycling guide
Easier: Dead bug heel taps · Harder: Forearm plank
3D demoKnee side plankBeginner · No equipment3 holds of 15 to 30 s each side · As in the back pain when cycling guide
Harder: Side plank
3D demoGlute bridgeBeginner · No equipment3 sets of 10 to 12 · As in the back pain when cycling guide
Easier: Pelvic tilt into bridge · Harder: Single-leg glute bridge
3D demoHalf-kneeling hip flexor stretchBeginner · No equipment3 holds of 30 s each side, pelvis tucked, no arch in the lower back · Editorial. Only if the front of the hip feels stiff and it eases your back. Pad the knee, as the move page says
Harder: Couch stretch
Move on when: 30 minutes of easy swimming in your chosen strokes stays within the pain rule, and the strength work feels steady.
From about week 6, twice a week, then ongoing: trunk and hip endurance for the streamlined position, with dryland strength brought back carefully, because dryland work was a common trigger. Swimming comes back by the written steps below. A young swimmer with a stress fracture of the spine goes back only when their clinician says so.
3D demoSide plankIntermediate · No equipment2 to 3 holds of 20 to 40 s each side · As in the back pain when cycling guide
Easier: Knee side plank · Harder: Side plank with leg lift
3D demoHollow body holdIntermediate · No equipment3 holds of 20 s · As in our dryland workout for swimmers, where it's the streamlined shape on land. Keep the low back pressed down, and rest your head in your hands if your neck does the work, as the move page says
Easier: Dead bug · Harder: Dragon flag
3D demoBack extension on a 45-degree benchIntermediate · A bench or box2 sets of 10 to 15, lifting to a straight line, no further · As in the back pain when cycling guide. Move slowly if arching aggravates your back, as the move page says
Easier: Ball back extension · Harder: Horizontal back extension (hyperextension, Roman chair)
3D demoSuitcase carryIntermediate · A dumbbell + A kettlebell3 carries of 20 to 30 m each side · As in the back pain when cycling guide
Easier: Farmer's carry · Harder: Overhead carry (waiter's walk)
3D demoKettlebell deadliftBeginner · A kettlebell3 sets of 8 to 10 · As in the back pain when cycling guide. A moderate weight, with heavier lifting last and away from hard pool days (our suggestion)
Easier: Hip-hinge practice · Harder: Dumbbell Romanian deadlift
Move on when: Our suggestion: keep adding distance, about 10% a week, while the pain rule holds; then breaststroke with your face in; then tumble turns, a kickboard held low and pull buoy sets, one at a time. Butterfly and long underwater dolphin kicks come back last.
Our 3D figure can't show these changes. They come from one small crossover study, surveys of competitive swimmers, Swim England's technique advice and reviews, and where a step is our suggestion, it says so.
No trial has tested a return after back pain in swimmers. The order follows the stroke study, the survey of triggers and the reviews; the amounts are our suggestion.
NICE says not to offer belts or corsets for low back pain; a brace for a young swimmer's stress fracture is a specialist's decision. A swimming review keeps facet joint injections for stubborn facet pain, and says it's rare for a swimmer with a disc problem to need surgery during their swimming career.
| Habit or position | Why it matters | Instead |
|---|---|---|
| Butterfly and long underwater dolphin kicks | Butterfly carried 2.5 times the risk of low back pain in elite swimmers and was the commonest trigger after a back injury, and swimmers with back pain arched more in the dolphin kick. | Backstroke and front crawl.Try: Front crawl (freestyle swimming) |
| Head-up kicking on a kickboard | Reviews say it arches the lower back, though one survey found swimmers who used kickboards more had fewer back injuries. | Kick on your back or side; if you use a board, hold it low with your face in the water (our suggestion). |
| Head-up breaststroke | Swim England says lifting the head rather than the shoulders to breathe can lead to back pain. | Face in the water, the head rising with the shoulders to breathe. |
| Tumble turns | Turns were a common trigger in swimmers with a past back injury. | Open turns (our suggestion). |
| Swimming on through pain, tingling or numbness that spreads down a leg | Leg symptoms are the exception to the pain rule. | Shorten or stop that stroke, kick or turn, and read the warning signs. |
| Heavy back squats and lifting on hard pool days | Dryland strength training was the second commonest trigger after a back injury, and activities outside the pool, such as strength training, caused 38% of one college team's injuries. | Trunk endurance work now; heavier lifting last, away from hard pool sessions (our suggestion).Try: Dumbbell goblet squat |
| The sphinx and other arching stretches, if arching backwards brings your pain on | Repeated arching is what reviews blame for swimmers' back pain. | A gentle knee to chest within comfort.Try: Single knee-to-chest stretch |
| The superman and other face-down back raises, if arching hurts | The same reason (our suggestion). | The bird dog, reaching long rather than high.Try: Bird dog |
| Bed rest, or stopping all activity | The NHS says not to stay in bed for long periods. | Walk every day.Try: Treadmill walking |
| A back belt or corset | NICE says not to offer belts or corsets for low back pain. | Exercise you'll keep doing. |
| Asking for a scan to find out what's wrong | Disc changes are common in swimmers and non-swimmers without pain, and NICE advises against routine imaging. | Get checked if a warning sign appears, or if a young swimmer's back hurts arching backwards. |
| A teenager training on through back pain that's worse arching backwards | A stress fracture of the spine can be missed for months. | A check with a GP or sports physiotherapist. |
A 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.
15 minBeginner6 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 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 equipmentA 45-minute dryland session for swimmers: jumps for starts and turns, heavy pulls, leg strength and trunk work, twice a week alongside the pool.
45 minIntermediate14 movesA band, A bench or boxUsually from repeated arching: every stroke holds some arch to stay streamlined, and butterfly, breaststroke, the dolphin kick and head-up kicking on a board arch it most, reviews say. Swimmers with back pain arched more in the dolphin kick and had stiffer hip flexors, and butterfly, dryland weights and turns were the commonest triggers after a back injury.
Often, modestly. In 76 adults with long-lasting back pain, a swimming and education programme beat education alone for disability at 8 weeks, though not at a year, and aquatic exercise eased pain in small trials. The NHS lists swimming among activities that may help, so choose the stroke that leaves your back steady or easier.
In 30 adults with back pain who swam 100 m of each stroke, backstroke hurt least and breaststroke most, with front crawl in between and not clearly different from backstroke. Butterfly is the usual aggravator. No stroke suits everyone, so use the pain rule.
It can be, mainly when the head is held up: Swim England says lifting the head rather than the shoulders to breathe can lead to back pain. Swim it with your face in, letting your head rise with your shoulders to breathe, or swap to backstroke or front crawl for a while.
It can: reviews say holding a board with the head up arches the lower back, though in one survey swimmers who used kickboards more had fewer back injuries. Kick on your back or side at first, or hold the board low with your face in the water, and keep what passes the pain rule (our suggestion).
Often, if it eases rather than worsens your symptoms: exercise helps back pain in general, and aquatic exercise helped in small trials. Stop or change any stroke, kick or turn that sends pain, tingling or numbness further down your leg, and see our sciatica and herniated disc guides.
For now, if they hurt: turns were among the commonest triggers in swimmers with a past back injury. Use open turns and bring tumble turns back once your back has settled (our suggestion).
Usually it's a strain. But back pain that lasts more than a couple of weeks, is worse arching backwards, as in butterfly, breaststroke and push-offs, or stops them training needs a GP or sports physiotherapist, because it can be a stress fracture of the spine. In four teenage elite swimmers, the diagnosis took months, and X-rays showed only two of the four cracks.
Probably not. Elite swimmers had more disc wear than recreational swimmers, but it wasn't linked with their pain, and disc wear is common in people without pain. NICE advises against routine imaging for low back pain.
Exercise of almost any kind helps long-lasting back pain, by about 15 points out of 100 against no treatment. For swimmers, reviews suggest trunk endurance more than heavy strength, plus hip extension range. The plan builds from walking and gentle movement to bird dogs, side planks and the hollow body hold.
Pain, tingling or numbness in both legs, numbness around the genitals or bottom, or bladder or bowel changes need a 999 call or A&E. Back pain with feeling hot, shivery or unwell, or severe pain that came on suddenly or is getting worse quickly, needs an urgent GP appointment or NHS 111. A teenager's back pain that's worse arching backwards needs a GP check.
Exercise education, not a diagnosis or treatment plan. It is written from the guidelines and studies listed above; review by a clinician is pending. If your pain follows an injury, is severe, is getting worse, or comes with any warning sign listed on this page, get it assessed. Health disclaimer.
