Muscle Knots: What They Actually Are and How to Get Rid of Them

Nearly everyone has felt one: a hard, sore lump somewhere in the upper trapezius or the glutes that hurts when you press it and sometimes sends pain somewhere else entirely. The standard explanation is that a patch of muscle fibres has contracted and stayed contracted, forming a physical knot. That story is intuitive, widely repeated, and probably not what's happening.

What a muscle knot really is

The clinical term is a myofascial trigger point: a tender nodule sitting inside a taut band of skeletal muscle, capable of producing local pain and referred pain some distance away. The taut band part is well supported. Ultrasound and shear wave elastography can detect these stiffer, thickened regions in people with myofascial pain, and a systematic review of imaging studies concluded that trigger points and taut bands do exist as genuine areas of increased muscle stiffness (Assessment of Myofascial Trigger Points via Imaging: A Systematic Review).

Where the popular story breaks down is the mechanism. The classic model, which comes out of decades-old work on muscle physiology, describes contraction knots: short segments of muscle fibre with sarcomeres jammed shut and a visibly increased diameter (Etiology of Myofascial Trigger Points). A 2025 study that biopsied upper trapezius tissue alongside ultrasound imaging found no contraction knots in any specimen, and suggested that what a therapist's thumb identifies is composite stiffness across the tissue rather than a discrete lesion (Ultrasound features of myofascial trigger points).

So the lump is real, the tenderness is real, and the referred pain is real. The tiny ball of seized-up fibres you've been told to "break down" probably isn't.

What causes them

Sustained low-level tension, more often than anything dramatic. The classic sites give it away: upper traps in people who work at a laptop, levator scapulae in anyone who cradles a phone against a shoulder, glute medius in people who sit all day, and forearms in anyone who's just started doing a lot of gripping work.

Training does it too, though usually through a sudden change rather than volume itself. Adding deadlifts back into a programme after six months off, or doubling your weekly running mileage, produces exactly the sort of unaccustomed load that leaves a spot in the glutes or calves sore and tight for a fortnight.

What actually helps

Heat, first. Local heat therapy increases blood flow to the area and appears to help functional recovery after strenuous eccentric exercise (Local Heat Therapy to Accelerate Recovery After Exercise-Induced Muscle Damage). Twenty minutes with a hot water bottle, a heat wrap or a bath, and then stretch. Stretching cold tissue is the least productive version of the same effort.

Pressure, moderately. A foam roller for the big muscles, a lacrosse ball against a wall for the shoulder blade and glutes, or a massage gun if you'd rather not lie on the floor. Ninety seconds per spot is plenty. The relief is temporary in every case, lasting a few hours rather than permanently, and that window is what you use to do the stretching and strengthening that actually changes things.

Movement through range. Whatever position the muscle has been stuck in, take it through the opposite one repeatedly. Desk-bound upper traps respond well to face pulls and shoulder blade retraction work; tight hips want hip flexor stretches and glute bridges.

Load it. This is the step people skip. A weak muscle that's constantly asked to hold a position will keep protesting until it gets stronger. Upper back knots in particular tend to fade once someone starts doing rows and rear delt work two or three times a week.

What doesn't help much

Stretching alone, done cold and briefly, for a knot that took six months of desk work to build. Pressing until it bruises. Chasing the sensation of the knot "releasing", which is largely a change in how the area feels rather than a change in the tissue. And buying a more expensive massage gun when the £60 one you own already produces the same short-lived relief; the premium models like the Theragun Prime are quieter and more comfortable to hold, not more curative.

When to get it checked

Book in with a physiotherapist or your GP if the pain wakes you at night, radiates down an arm or leg with pins and needles, hasn't budged after six weeks of sensible self-treatment, or arrived without any obvious cause alongside weight loss or fever. Persistent one-sided neck and shoulder pain in particular is worth a proper assessment rather than another month of thumbing at it.

Recommended reads

• Best massage gun UK
• Best foam roller UK
• Trap exercises for a stronger, less achy upper back
• Face pulls: technique and why they fix desk shoulders
• Hip flexor stretches