Why does my shoulder hurt when I lift my arm?
Pain through a specific arc as your arm goes up — usually somewhere between shoulder height and ear height — typically means rotator cuff tendons being compressed in a space that’s briefly too small. How much space there is depends largely on how your shoulder blade moves, and that’s trainable.
What you’re feeling
The giveaway is that it hurts in the middle of the movement rather than throughout it:
- Pain through a band of the range — often roughly between shoulder and ear height
- Comfortable at the very bottom and sometimes fine again at the very top
- Worse reaching into the back seat of a car, putting on a coat, or washing your hair
- Aches at night, particularly lying on that side
- Feels weak rather than painful when you’ve had it a while
- Clicking or catching as the arm passes through the sore range
A painful arc with full range is the reassuring version. Losing range — including when someone else moves your arm for you — points elsewhere, and that’s below.
Why it’s happening
The rotator cuff tendons pass through a gap between the top of the arm bone and the bony roof above it. Anything that narrows that gap, or asks the tendons for more than they can give, produces this:
A mid-back that won’t extend
Your shoulder blade has to rotate upward and tilt back for your arm to clear the range. It can only do that if the ribcage underneath it is able to extend. A rounded, stiff thoracic spine physically reduces the space available, and no amount of shoulder exercise gets around it.
Rotator cuff without endurance
The cuff’s job is to hold the arm bone centred in the socket while the big muscles move it. When the cuff fatigues, the arm bone rides upward slightly on each lift and the tendons get pinched against the bone above. Fatigue, not weakness, is often the issue.
A shoulder blade that isn’t controlled
Lower trapezius and serratus anterior steer the shoulder blade through the lift. When they’re not doing it, the blade shrugs upward instead of rotating, and the space closes at exactly the moment you need it open.
Too much overhead, or too little
Both directions cause it. A weekend of painting ceilings will do it, and so will a decade of never lifting anything above shoulder height followed by one enthusiastic session.
Stop and see a doctor if any of these are true
- You can’t lift the arm at all, particularly after a fall — that needs assessment for a tear or fracture
- Range is getting steadily worse over weeks, including when someone else moves your arm for you
- Shoulder pain with chest tightness, breathlessness, sweating, or jaw and arm pain — call emergency services
- Sudden severe pain with a visible change in the shape of the shoulder
- Night pain accompanied by fever, weight loss, or feeling generally unwell
The second point is the one people miss. A shoulder that is progressively losing range in every direction, including passively, may be a frozen shoulder — and that has a treatment window where early input genuinely changes the course. Don’t spend six months on cuff exercises for it.
How to fix it
Open the space first, then teach the shoulder blade to move, then build the cuff’s endurance. Loading a cuff inside a space that’s too small just keeps irritating it.
Thoracic extension over a roller
Foam roller across the mid-back, hands supporting the head, ease backwards over it and breathe out. Move the roller an inch and repeat. This is the piece that makes everything else work, and skipping it is why most shoulder programmes stall.
5 positions × 3 breaths, dailyWall slides
Forearms on a wall, slide them upward while keeping contact and keeping the ribs down. Stop where it stops being smooth. You’re training the shoulder blade to rotate rather than shrug, in a position where the wall gives you feedback.
10 reps × 3, dailyIsometric external rotation
Elbow at your side bent to ninety degrees, press the back of your hand into a doorframe and hold. No movement. This calms an irritable cuff and builds tolerance without dragging the tendon through the painful arc.
30 seconds × 5, dailyBanded external rotation
Same position, now moving against a light band. Slow out, slower back. Light enough that you could do twenty; the cuff responds to endurance work far better than to heavy loading.
15 reps × 3, every other dayReintroduce overhead, at an angle
Raise a light weight in the scapular plane — about thirty degrees forward of straight out to the side, thumb leading. That angle gives the tendons the most room. Start with no weight at all and add slowly over weeks.
10 reps × 3, 3× weeklySix to twelve weeks is the usual timeline and progress tends to appear as a narrowing of the painful arc rather than a sudden absence of pain. If you’re losing range instead of gaining it at any point, stop and get assessed.
Shoulders and mid-back, twenty minutes
The whole progression in order, with the thoracic work given the time it actually deserves.
Start the free classQuestions people ask next
Does this mean I’ve torn my rotator cuff?
Probably not, and even a scan showing a tear wouldn’t settle it. Partial cuff tears are found in a large proportion of people over fifty who have no shoulder pain at all. Tears are common; painful shoulders are a separate question, and most improve with loading regardless.
Should I rest it?
Rest the aggravating activity, not the shoulder. Stop the ceiling painting, keep doing the exercises. Shoulders that are fully rested get stiff quickly, and stiffness is a much harder problem to unpick than soreness.
Do I need a scan?
Rarely, at least at first. Scans of shoulders find abnormalities in almost everyone past middle age, which means the result often adds anxiety without changing the treatment. If twelve weeks of good rehab hasn’t helped, that’s the point to image it.
Is the clicking a problem?
By itself, no. Shoulders are noisy joints and noise correlates poorly with anything. Clicking accompanied by pain, catching, or a sense of the shoulder slipping is worth mentioning to a clinician; clicking on its own isn’t.