Muscle Tears & Strains
A muscle tear — or muscle strain — happens when the fibres of a muscle are overstretched or overloaded and some of them give way. They are common in sport and everyday life, and the good news is that muscle has a real capacity to heal. With the right plan, most people recover fully and get back to what they love.
What happens when a muscle tears
A muscle is made of thousands of fine fibres bundled together, blending into a tendon at each end. When the load on the muscle is greater than the fibres can handle, some of them tear — most often at the muscle–tendon junction. This causes pain, weakness, swelling and sometimes bruising, as small blood vessels tear too.
What a muscle tear actually looks like on a scan. These are real MRI images of muscle injuries. The bright white patches are the injury: fluid, swelling and bleeding where the fibres have torn.
Reading the grid: each row is a different type of tear by where it sits — in the tendon (a), at the edge of the muscle (b), in the central seam of the muscle (c), or within the muscle belly itself (d). Reading left to right, each row runs from a mild strain to a complete tear — the same jump from a Grade 1 to a Grade 4 injury.
Where this sits in the healing cycle: a scan like this is almost always taken in the first days to a couple of weeks after injury — the acute, inflammatory stage. That bright glow is exactly the swelling and bleeding your body floods into the area to kick-start repair. As the injury moves on through the repair and remodelling stages over the following weeks, the brightness settles and the tissue knits back together — which is why an early scan looks so dramatic even when the outlook is good.
MRI images: Isern-Kebschull J, et al. “Sports-related lower limb muscle injuries: pattern recognition approach and MRI review.” Insights into Imaging 2020;11(1). Used under CC BY 4.0.
Tears range from a Grade 1 strain of a few fibres to a Grade 4 complete rupture. The more fibres involved — and whether the tendon is caught up in it — the longer the healing takes.
Grades & typical recovery times
Specialists now use the British Athletics Muscle Injury Classification (BAMIC), introduced by Pollock and colleagues in the British Journal of Sports Medicine (2014). It grades tears 0–4 and notes where in the muscle they sit. It’s a useful guide to recovery — though every injury and every person is different.
| Grade | What it means | Typical return to training |
|---|---|---|
| Grade 0 | Soreness only — no structural tear (focal niggle or DOMS) | Days–2 weeks |
| Grade 1 | Small tear — pain with activity, strength largely intact | ~1–3 weeks |
| Grade 2 | Moderate / partial tear — activity stops, clear weakness | ~4–8 weeks |
| Grade 3 | Extensive tear — sudden pain, obvious weakness & bruising | ~8–16 weeks |
| Grade 4 | Complete tear or rupture — palpable gap, little force | Months (± surgery) |
Timeframes are indicative and vary with the muscle, the sport and the person. Source: Pollock N, James SLJ, Lee JC, Chakraverty R. British athletics muscle injury classification: a new grading system. Br J Sports Med 2014;48(18):1347–1351. Read the paper.
Common muscle tears & how they happen:
How a muscle heals
A healing muscle moves through four overlapping stages. Understanding them is powerful, because what you do at each stage — and when you load it — has a big effect on how well it recovers.
The tear
When the load on a muscle is greater than its fibres can take, some of them give way — most often at the muscle–tendon junction. The torn ends recoil slightly, small blood vessels rupture, and the muscle starts to bleed into the gap. This is the moment of injury, and it sets off everything that follows.
Inflammation
The bleeding forms a haematoma in the gap, and the damaged tissue releases inflammatory chemicals — cytokines and growth factors. These summon immune cells, first neutrophils and then macrophages, which clear away the broken tissue. This clean-up phase feels like the “bad” bit, but it is essential: the same chemicals that cause the swelling are the signals that switch on repair.
Repair
Muscle’s own satellite (stem) cells wake up, multiply and begin rebuilding muscle fibres at the torn ends. At the same time fibroblasts move in and lay down collagen to bridge the gap — the beginnings of scar tissue — while new blood vessels sprout in to feed the rebuild. Gentle, graded loading now starts to steer this new tissue to form along the right lines.
Remodelling
Slowly — over weeks to months — the new muscle and collagen mature, thicken and re-align along the lines of stress. The scar shrinks down to a small, strong seam and the blood supply settles. Progressive strengthening and return-to-sport loading in this stage are what turn a soft patch of scar into resilient tissue, and lower the risk of re-tear.
Scar tissue — and why it matters
A torn muscle almost never heals as pure new muscle. Some muscle regenerates from satellite cells, but the gap is mostly bridged by scar tissue — a repair made of collagen. Understanding how that scar behaves is the key to a full recovery.
In the early days, fibroblasts lay collagen down quickly and in a hurry. This first scar is mostly type III collagen — thin, disorganised and laid in a random, criss-cross mesh. It plugs the gap fast, but it is weak, stiff and nothing like the stretchy, well-aligned muscle it replaces. Left alone, that is roughly how it would stay: a stiff knot that pulls on the healthy tissue around it, limits how far the muscle can stretch, and is far more likely to tear again.
What happens next is called remodelling, and it is the most important — and most overlooked — part of healing. Over weeks and months, the body gradually swaps that weak type III collagen for stronger, thicker type I collagen, and the fibres slowly re-organise. Crucially, they re-align along the lines of stress — the directions the muscle is actually pulled in. A messy mesh is reorganised into orderly, parallel cables that can take load. The scar shrinks, softens and blends into the muscle, and strength and flexibility return.
Here is the part that matters most: collagen remodels in response to load. Tissue only knows which way to lay its fibres because of the forces you put through it — a process called mechanotransduction. Rest a healing muscle completely and the scar stays disorganised, stiff and weak. Load it carefully and progressively, and you give the collagen the instructions it needs to line up, strengthen and become functional tissue.
Early management that helps, not hinders
Protect early, then move
In the first day or two, protect the muscle and avoid things that sharply increase the pain. After that, gentle movement and graded loading — guided by a physio — help it heal better than rest alone. The modern approach is PEACE & LOVE, not weeks on the sofa.
Get the grade checked
It is worth having a tear assessed early. We confirm the grade and the structures involved (muscle, tendon or both), rule out anything that needs a scan, and give you a timeline and a plan rather than guesswork.
Physiotherapy assessment for a muscle tear
Your initial physiotherapy appointment will consist of two key components:
Subjective assessment
A detailed discussion about how the injury happened, what you felt, how it is affecting you, your training or sport, and any relevant history. We will also explore your goals and timelines — including any event you are working towards.
Objective assessment
A physical examination of the muscle’s strength, length and tenderness, plus special tests to estimate the grade and the structures involved. Where it will change your plan — or if we suspect a significant tear — we can arrange a diagnostic ultrasound scan.
At The Treatment Table, we also offer diagnostic ultrasound scanning in-house, so we can look at the muscle directly when it helps.
Rehab that matches the healing process
Your treatment is built around the phase of healing you are in, and may include:
Protected early loading (not prolonged rest)
Progressive strengthening
Eccentric and lengthening exercises
Range-of-movement work
Soft tissue therapy & massage
Graded return to running
Return-to-sport testing
Addressing why it happened
At The Treatment Table, we guide you through every phase — settling the injury early, rebuilding strength as it repairs, and loading it properly as it remodels — so you return to sport and daily life confident, strong and far less likely to tear it again.
Book your muscle tear assessment
Whether it’s a fresh injury or a tear that keeps coming back, a specialist physiotherapy assessment gives you the diagnosis, timeline and rehab plan you need.
A muscle tear is a strain of the muscle fibres, graded 0 to 4 by how many are involved and where. Muscle heals in three phases — inflammation, repair (where fibroblasts lay down collagen) and remodelling — and the load you apply at each stage shapes how strong the repair becomes.
For more information or to book an appointment, contact The Treatment Table on 0151 559 1107 or email info@thetreatmenttable.com.
Book your assessment