What the press asks of the shoulder, and what no study has countedEmerging evidence
In an overhead press the arm goes from the front of the shoulder to straight overhead under load, and the shoulder blade has to turn upward and tip back so the socket follows the arm; in a motion study of 16 men, the press did this more than a plain arm raise. The arm finishes in the position the NHS says brings on rotator cuff pain, "especially when you lift it above your head", and a UK pathway from the British Elbow and Shoulder Society (BESS) describes "mid-arc pain with overhead activities".
No study counts shoulder pain caused by the strict overhead press. In an online survey of 187 CrossFit athletes, "overhead press (any variation)", which included push presses and jerks, was named for 13 of 46 shoulder injuries, and people could name more than one cause. In 386 CrossFit athletes, at most 2 of 21 shoulder injuries came from the whole squat, deadlift, press and bench press group; in 110 elite weightlifters and powerlifters, no shoulder injury was linked to any one exercise; and in elite weightlifters most shoulder injuries were strains, with 90.5% of all injuries costing a day or less. Across weight training the shoulder is among the commonest injury sites, from 7% to 46% of injuries in 11 lifting studies.
So the map on this page is built from what each condition is known to do, pressing lab studies and health-service pages. Pain usually comes when the load, or a jump in it (more pressing days, heavier sets, a new variation, behind-the-neck pressing), gets ahead of what the shoulder is used to; that is our reading, not a counted fact.
Sources 1, 2, 3, 4, 5, 6, 7, 8, 9
The outside and front: the rotator cuff and the biceps tendonEmerging evidence
Rotator cuff pain is the commonest cause of shoulder pain, about 70% of cases according to the authors of a large UK trial. The NHS describes pain "at the top and the outside of your shoulder", worse lifting the arm, especially above your head, and the BESS pathway says it is "made worse by shoulder level or overhead activities". A painful arc partway up that eases at the top is typical.
The long head of the biceps runs in a groove at the front of the shoulder. The American Academy of Orthopaedic Surgeons (AAOS) describes front-of-shoulder pain "which worsens with overhead lifting", and says biceps tendon pain usually comes alongside other problems such as the rotator cuff.
Sources 10, 2, 3, 11
On top of the shoulder: the AC joint and weightlifter's shoulderEmerging evidence
Pain you can cover with one finger on top, at the end of the collarbone, points to the AC joint. An NHS leaflet names "Repeated heavy or high arm work e.g. weight lifters" and reaching across the body among the causes of AC joint pain.
Weightlifter's shoulder (distal clavicle osteolysis) is an overuse injury of the end of the collarbone. In a review of 8 studies (483 people), the activity was bench pressing in 49.1% and general weight training in 24.4%; pressing more than 1.5 times body weight (56% against 6%) and training 3 or more times a week were linked with it. In 25 weightlifters, 28% had X-ray signs of it against none of 25 men who didn't lift. These studies count bench pressing and weight training in general, not the overhead press, so for the press this is borrowed evidence.
Sources 12, 13, 14, 15
Deep in the joint, a shoulder that slips, and torn tendonsEmerging evidence
The labrum is the rim of the socket. The AAOS names weightlifters among the people who tear its top (a SLAP tear), with locking, catching and "Pain with lifting objects, especially overhead", and says that over 30 to 40, fraying is "a normal process of aging": scans read tears in 55% and 72% of 53 pain-free 45 to 60 year olds.
A shoulder that clunks, gives a dead arm or feels as if it will slip is more likely with the arm up and turned back. In 123 weight trainers and 36 people who didn't lift, those who did behind-the-neck presses and pulldowns had more signs of a loose shoulder (a cross-sectional study, so it can't show cause), and those who strengthened the muscles that turn the arm out had fewer. In 20 lifters with a hidden loose shoulder, the arm-out, turned-back position brought on the pain, and one weightlifter dislocated both shoulders in a seated behind-the-neck press.
A torn long head of the biceps brings a sudden sharp pain, sometimes a pop, bruising and a "Popeye" bulge low in the upper arm; the AAOS names heavy overhead lifting and too much weight among the risks, and says these tears "rarely need surgery" unless something such as the rotator cuff is damaged too.
Sources 16, 17, 18, 19, 20, 21
When in the press it hurtsEmerging evidence
Partway up, then easing at the top: typical of rotator cuff pain. Changing the path (a landmine press, which rises up and forward rather than straight up, or dumbbells with the palms facing in) and stopping short of the painful point are the usual first changes; no study has tested either in people with pain.
At the top, at lockout: one spot on top at the end of the collarbone points to the AC joint, and a deep ache on the outside to the rotator cuff. One review's figure advises raising the arms "slightly in front of the head without extending completely", and popular pages disagree about lockout. No study has measured it, so stopping short of the painful point for now is our suggestion.
At the bottom, with the bar at your shoulders: the biceps groove or the front of the joint, and with a behind-the-neck press, the arm-out, turned-back position that goes with signs of a loose shoulder (our reading; no study has measured the bottom of the press). On the bench but not overhead, or the other way round: weightlifter's shoulder was linked mainly with bench pressing, and rotator cuff pain with overhead work, so the lift that hurts is a clue, not a diagnosis.
Sources 3, 22, 11, 18, 12
Rare but serious: the heart, a dislocation and infectionEmerging evidence
The heart can show up as shoulder or arm pain, often the left. The NHS sends chest pain that feels tight or squeezing, or chest pain that spreads to the arms, neck or jaw, to 999, and heavy pressing is hard exercise, so arm or chest discomfort that comes on with effort and eases with rest is in the warning signs too. A shoulder that looks out of place after a missed rep or a fall goes to A&E, and a hot, swollen or red shoulder, especially if you feel unwell, can be a joint infection, which needs same-day care.
Sources 23, 24, 25, 26
What a scan shows, and what it doesn'tStrong evidence
The BESS pathway says rotator cuff pain "is a clinical diagnosis. Additional imaging is not essential to confirm the diagnosis or start treatment." An X-ray matters after a missed lift or a fall, with warning signs, severe pain or stiffness, or pain lasting beyond about 4 weeks; a suspected dislocation is X-rayed in hospital. An ultrasound or MRI scan is for ongoing symptoms, and weightlifter's shoulder usually needs an MRI to confirm (marrow swelling showed in 72.2% of cases).
Read reports with care. In 96 people without shoulder pain, MRI showed rotator cuff tears in 34% (54% of those over 60); AC joint arthritis showed in 70% of 210 MRI scans of pain-free shoulders, and across studies AC joint changes showed in 13% to 95% of shoulders without symptoms, often as often as in painful ones; radiologists read superior labral tears in 55% and 72% of 53 pain-free 45 to 60 year olds; and ultrasound showed rotator cuff tendon changes in 14 of 15 young weight trainers against 41% of non-lifters.
Sources 3, 24, 12, 27, 28, 29, 17, 30
How it usually goesEmerging evidence
No study follows shoulder pain from overhead pressing. In 349 people with new shoulder pain in Dutch general practice, 23% had recovered at 1 month and 59% at a year, quicker after overuse or a slight injury and slower with neck pain or severe pain in the day. The BESS pathway calls this kind of pain "usually a self-limiting condition" with most symptoms responding within three months, and refers people not improving by 12 weeks. The NHS says shoulder pain usually takes 2 weeks of looking after it to start easing and "can take 6 months or longer to recover"; an NHS booklet says about half settles in about 6 months.
Weightlifter's shoulder mostly improved without surgery, often after cutting back or changing training. In a CrossFit survey, 64.1% of people with a shoulder injury cut their training for a month or less. No one can promise a date.
Sources 31, 3, 26, 32, 12, 4