I am a science writer and a former Registered Massage Therapist with a decade of experience treating tough pain cases. I was the Assistant Editor of ScienceBasedMedicine.org for several years. I’ve written hundreds of articles and several books, and I’m known for readable but heavily referenced analysis, with a touch of sass. I am a runner and ultimate player. • more about me • more about PainScience.com
Muscle strains strike most often in the big muscles of the body. But sometimes the pain is not what it seems …
Welcome to the most detailed information about muscle strain and muscle pain available anywhere, especially for tough and stubborn cases. This is more than just a web page: it’s bigger than it looks — many dozens of chapters and over 100,000 words, including a second volume — for both patients and professionals that explores every myth and controversy, and every possible way of reducing pain coming from muscle. It is more scientifically current than any competitive information source, yet also more user-friendly and readable.
In 2012, Gene Lawrence, a 74-year-old weight lifter, tore his quadriceps (and not while lifting). A doctor cautiously told him he’d never do a squat again. But Gene’s passion for his sport kept him going. Several months later he was on the verge of beating his personal records — a near total recovery. You can recover from nearly anything if you are patient and methodical.1
But what method? What is muscle injury, and how does it heal? Is your muscle actually injured? What works? What doesn’t? Muscle strain and pain are usually woven together. Somewhere in your body, something hurts and you think it’s got to be a muscle strain or a muscle spasm or … well, something to do with a muscle anyway. If you’re like most people with muscle pain, you’re not sure exactly what the problem is, and you’re looking for some answers.
I am a science writer & amateur athlete in Vancouver, Canada. I’ve been writing about muscle strains for more than a decade & recovered from several that I’ve gotten while playing sports. ~ Paul Ingraham
About footnotes. There are 46 footnotes in this document. Click to make them pop up without losing your place. There are two types: more interesting extra content,1Footnotes with more interesting and/or fun extra content are bold and blue, while dry footnotes (citations and such) are lightweight and gray. Type ESC to close footnotes, or re-click the number.
and boring reference stuff.2“Boring” footnotes usually contain scientific citations from my giant bibliography of pain science. Many of them actually have pretty interesting notes.
Believe it or not (and it does seem a bit ridiculous in 2017) muscle pain is still a subject of great scientific mystery and many myths and misconceptions. A torn muscle is arguably among the most medically neglected of all common injuries.23 Odds are good that your family doctor is not competent to assess and treat musculoskeletal problems, including muscle strains.4
pro Strong enough for a pro But made for patients. The main text is user-friendly, but oodles of footnotes provide extra info and citations.
I do criticize many common practices and beliefs. If you disagree, let me know—I can take it, and I’ve made many changes over the years based on quality feedback.
And so, although most muscle pain is relatively simple to diagnose and self-treat, an incredible number of people seek treatment for muscle strains that have been misdiagnosed as something else … or they have “something else” that’s been misdiagnosed as a muscle strain. Strain, pain, spasm, contracture, scar tissue, tone, tension, and stiffness are all poorly understood and routinely confused. They are not only surprisingly complex topics scientifically, but clinicians are not generally aware of the research that has been done.
The world obviously needs more and better information about muscle pain.
How can you trust this information about muscle strains?
So all the science and all the options for muscle strain treatment are here. If you’ve been struggling with pulled muscle injury, I think this tutorial will feel like a “good find” to you!
As with all the tutorials on PainScience.com, I’ve worked hard to provide you with the best information available anywhere — not just better researched and referenced, but also regularly updated, and presented in a clear, friendly style that’s just like coming to my office and having a nice long conversation about it, where all your questions get answered.
So what is a muscle strain?
Actually, it's simple: any torn muscle is called a muscle strain. And this is the same as a “pulled muscle.”
(Note that there is no such thing as a “muscle sprain” — it’s a contradiction in terms.5)
Although you might have problems that make you vulnerable to a muscle strain, the direct cause of every muscle strain is traumatic ripping of the muscle tissue — arg! — usually at the point where the muscle meets its tendon. Muscle will tear under the force of your own muscular contraction, or excessive stretch.
The more muscle fibres are torn, the worse the strain. In the case of a serious strain, the entire muscle may completely rupture — literally ripped in half! Triple arg! (Total ruptures are serious injuries, much worse than partial ruptures.)
Muscle strains are particularly common in the thigh and groin in soccer, ultimate, hockey and other fast-moving team sports.
Sometimes an impact or a laceration damages muscle fibres in such a way that the injury is basically like a muscle strain. We won’t discuss this scenario much, because there’s not much medical mystery involved if you were gouged by a hockey skate. We also won’t discuss full muscle ruptures in much detail, because they are so extreme that they are easy to diagnose — even doctors can do it! 😃 If you have a doctor who can’t help you with lacerations and contusions, you really need a new doctor.
There will be much (much) more detail below about exactly what a muscle strain is, and its complications, and how to treat it, and so on. But before we get into that, it’s important to determine whether or not you actually have a muscle strain, or some other kind of muscle pain.
How do you know that you’ve got a muscle strain?
Here is the part where I tell you that you probably have the wrong book. But the right book is included for the many people who need it.
Muscle strains and especially muscle ruptures are actually surprisingly rare, compared to other causes of muscle pain. Funny thing about this tutorial: most people who find this document, like most people who think they have strained a muscle, have actually not done any such thing — or (just as common) they strained a muscle once upon a time, but the strain healed long ago and has since become an entirely different problem.
This could be you!
Most people who think they have strained a muscle have actually not done any such thing.
Some of the things that get confused with muscle strains are (and these will all be covered in more detail below):
Muscle cramps and spasms (charlie horses) are whole muscle contractions, ranging from uncomfortable to those howling, awful attacks that usually afflict the calves and feet.
Nasty muscle knots, technically known as trigger points, are small patches of localized muscle spasm and involve no actual damage to the muscle.
Delayed onset muscle soreness, a.k.a. DOMS, is that savage muscle soreness we all get after an unfamiliar workout … but it always (really) fades after about three days, guaranteed.
Low back pain is a complex phenomenon which routinely gets attributed to muscle strain, when in fact it is very rarely caused by muscle strain. Just about the only time low back pain is ever caused by muscle strain is when you have a sudden, severe onset of pain while trying to move a piano down some stairs … or something like that. (If you have low back pain, stop reading this article right now and head on over to Save Yourself from Low Back Pain!)
Cramp versus strain example: Multi-muscle cramping catastrophe on a hot summer night
Back in the late 2000s I was enjoying my athletic peak and just barely managing not to embarrass myself with younger and more talented athletes. One hot summer night I was running low on electrolytes: too much sweating, not enough salt intake. (Actually, that’s a surprising myth.6) I was playing “goaltie” (say it like goal-tea) a variant of ultimate: a hard-running Frisbee sport with the same intensity and speed as soccer, but with more jumping.
Both calves spasmed on a jump, bringing me down hard. That was nasty, but it was just the start: as soon as I hit the ground, both sets of hamstrings went off as well, and all that was more than enough to make for a good cramping story … but then my abdominals joined the fray, and that gave me an anecdote I’ll be sharing for the rest of my life.
The cramping all hurt, a lot, but I was too surprised and busy to focus on the pain. If you’ve ever had a strong spasm, you know that there’s a powerful instinct and need to elongate the muscles. Stretching is your only hope of relief. But I had a puzzle to solve: just try to stretch the backs of your legs and your abdominal muscles at the same time. It’s an anatomical impossibility.
That’s me in the air at the back. Check out that vertical! It was that kind of jump that triggered a massive wave of spasms …
I jackknifed back and forth so violently that the other players wondered if I was having a seizure, but I was simply on my impossible mission to stretch both sides of my body. If I stretched the legs, the abdominals would bunch up; if I stretched them, the leg muscles tried to kill me. After about three tries each way, I realized it couldn’t be done and that my only hope was compromise: to find the least awful position somewhere between the extremes. It meant that neither muscle group would really be stretched at all — but neither would be allowed to fully contract either. I gasped “cramps! lots of cramps!” so everyone knew I wasn’t actually having a seizure … and then waited it out.
Without the power of stretch, the cramps took a long time to fade. It was a long time to endure extremely powerful contractions.
A spasm is capable of injuring muscle. In this case, I was wrenching back and forth, my own muscles in a tug-of-war with each other. These were perfect conditions for injury. Something had to give, and it did — I had mild strains of all the affected muscles, resulting in not just days of soreness but severe soreness for weeks, and a vulnerability to reinjury that was still a problem a full year later.
The spasm here was the strong involuntary contraction of the muscles. The strain was the injury caused by the forces on the muscles.
True muscle strain checklist
Here’s a checklist of the signs and symptoms of a true pulled muscle. If you can say, “Yeah, that’s me,” to all of these, then congratulations: you probably have an actual, certifiable, card-carrying Muscle Strain®.
Did it hit you suddenly during strong stretching or a moment of athletic intensity? Were you lifting something way too danged heavy and/or awkward? In other words, did you have an “oh, shit” moment?
Is the injury fairly recent? A few weeks old at the most? If it’s been a long time, it’s probably not a muscle strain any more — certainly not an acute one!
Do you have just one muscle (or muscle group) that’s both weak and painful to use?
Is there a spot in the muscle that’s especially sensitive? (It may even be little bit deformed — is there a bump or a depression?)
Is the skin flushed and hot? Does it look puffy?
If you “woke up with it,” or the pain came on slowly over several days, or if it’s six months old, or if the pain isn’t consistently in one particular place … then we’ll be talking about other possibilities. If your real problem is actually a painful “muscle knot,” for instance, you might want to take your knots for a nice massage — but massage is mostly pointless for a strain.
The “oh shit” moment: the most essential sign of muscle strain
Muscle strain cannot occur without an “oh shit” moment. (It’s fun to explain oh-shit moments to my patients — it always gets a laugh!) In other words, it hits suddenly: you know that something nasty has happened, immediately and with perfect clarity. You feel wounded. In physical therapy, this is what we call a history of “sudden onset.”7
If your pain didn’t start suddenly (or very nearly so), it ain’t a muscle strain. Muscle strains are traumatic by nature, almost always occurring during intense athletic activity. The victim says a bad word, perhaps several of them in the case of a grade II injury. In the case of a grade III, there is generally screaming and falling down and probably turning a bit green.
And yet …
Rupture: not as obvious as you’d think!
Complete hamstring avulsions — that is, complete ruptures of muscles where they attach to bones — are not necessarily obvious. They aren’t all as painful initially as they sound (not a strong “oh shit” sign). And according to O'Laughlin et al, they “can be difficult to diagnose acutely due to swelling and patient guarding, which may mask a visibly palpable defect and lead to delays in diagnosis.”8 Yikes!
In that case study, the only diagnosis was “hamstring pain” for several days, before the avulsion was finally confirmed by MRI, and surgically repaired on day 13. It’s not hard to imagine cases where the diagnosis would have taken much longer — too long.
So how would you know? Many of the other signs discussed here would be relatively obvious, especially substantial weakness. If the muscle is actually detached, obvious there will be a loss of strength. With some muscles, the loss is total or close to it.9 In the case of the hamstrings, there are other “strings” that can take over — which is another reason why a hamstring rupture is surprisingly hard to diagnose. The strength loss would be dramatic, probably about one third (because there are three hamstrings: the semitendinosus, semimembranosus, and biceps femoris), but it’s interesting how non-obvious that is.10 But anyone with a hamstring rupture is going to have a significant performance problem.
Location, location, location
Another way of knowing you’ve got a muscle strain is by the location. Muscle strains are much more common in some muscles than others. Every “groin pull” is a muscle strain of one or more of your hip adductors, for instance.
You can strain virtually any muscle in your body, but the commonly strained muscles are:
the rectus femoris (the smallest of the quadriceps group, on top of the thigh)
gastrocnemius (the muscle that gives the calf its shape)
the lumbar paraspinals (thick columns of muscle on either side of the lumbar spine)
The pattern here is big muscles, which we tend to use for explosive or intense effort. However, a strain is possible in any muscle.
Even more specifically …
Strains often occur where muscles meet tendons, the myotendinous junction. Tendon is the shiny white “bio rope” that connects muscles to bones (in contrast to the bone-to-bone connections of ligaments). Tendons blend smoothly into muscles, like fingers of two types laced together, but at a cellular level. When a muscle contracts, the greatest strain naturally occurs where it pulls, which is of course where the tendon is. All the force converges on the tendon, but it’s not going to give. (In many cases, even bone will give way before tendon does!) Tendon has an extraordinary tensile strength, much greater than steel cable. Instead, the muscle tissue tends to fail close to where it becomes more tendon-y.
It can be hard to tell where this zone of likelier is. For instance, in the hamstrings, the tendons are quite long and complex, and blend into the muscle along a considerable span. So you can have a myotendinous strain there that is basically right in the middle, between thigh and knee.
The hurtin’ and the weak
You know you have a muscle strain when the muscle feels weak and contraction is painful.
Strength/pain combinations are very useful diagnostically, and a good physical therapist is always looking for such combinations when assessing your case. A “weak and painful” contraction test indicates muscle strain. “Strong and painful” means something else. “Weak and painless” something else again.
Ligament sprains, for instance, do not cause weakness or pain with muscle contraction — except to the extent that sprained ligaments just don’t like to be moved. If you simply clench your muscles in place, without moving, and nothing hurts (much) … that could be a ligament sprain: strong and painless.
Is this a sprain or a strain?
Definitely a sprain. Stabilizing a joint like this is for sprained ligaments, not strained muscles. Sprains always occur at joints, especially the ankles, knees and wrists.
Tendinitis is sometimes mistaken for a muscle strain. But tendinitis will not cause significant weakness. It will just hurt: strong and painful.
Muscles strains make muscle contractions really weak and painful.
Now let’s look at the three alternative diagnoses, three common muscle problems that get mistaken for muscle strains: muscle spasms, DOMS, and muscle knots …
Could you have a muscle spasm instead of a strain?
You sure could! Spasms, cramps and “charlie horses” can both seem like a muscle strain and they can also actually cause one…
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Volume I Contents
TABLE OF CONTENTS PREVIEW
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Volume II Contents (a separate tutorial but delivered automatically with this one, and, yes, it’s much bigger)
TABLE OF CONTENTS PREVIEW
1.1 Trigger point therapy is not a miracle cure for chronic pain — but it helps
1.2 What exactly are muscle knots?
1.3 Why muscle pain matters so much
1.4 How can you trust this information about muscle pain?
1.5 Why are trigger points so neglected by medicine?
1.6 Does your trigger point therapist have the big red books?
•1.7 A brief note about the relationship between fibromyalgia and myofascial pain syndrome
1.8 Trigger points may explain many severe and strange aches and pains
1.9 Two typical tales of trigger point treatment
•1.10 The myth of the trigger point whisperer
2 Diagnosis How can you tell if trigger points are the cause of your problem?
2.1 Trigger point diagnosis is not reliable … but it also may not matter that much
2.2 Where are the charts and diagrams of trigger point locations in this tutorial?
2.3 Quick checklist: classic trigger point symptoms
•2.4 Slow checklist: a more detailed diagnostic checklist for myofascial pain syndrome
2.5 Negative checklist: symptoms that are probably not caused by trigger points
2.6 If you have trigger points, will your muscles be “tight”?
•2.7 Identifying your trigger points by feel
2.8 “Out of nowhere”: a signature symptom of trigger points
2.9 Chasing pain: hurting in all the wrong places
2.10 Nerve pain is overdiagnosed
2.11 Case study: a story about nerve pain that wasn’t really nerve pain
2.12 Morning symptoms: an uncomfortable daily mystery for many people
2.13 From the frying pan of injury pain to the fire of trigger point pain
2.14 Could it be __________? Several specific problems that trigger points get confused with
2.15 Case study: “Bursitis” strikes again!
2.16 Predictably unpredictable: trigger point symptoms are erratic by nature
2.17 All the noise! Trigger points, joint popping, and crepitus
2.18 What are the worst-case scenarios for myofascial pain syndrome?
2.19 Worst Case Scenario 1: Being triggery
2.20 Worst Case Scenario 2: Rare but extremely severe cases of myofascial pain syndrome
2.21 Worst Case Scenario 3: Quick-start trigger points
•3 The science of trigger points It’s a little half-baked, but at least it’s not boring
3.1 The dominant theory of trigger points spelled out in a little more technical detail
•3.2 Micro muscles and the dance of the sarcomeres
3.3 One: The vicious cycle (why trigger points are stubborn)
•3.4 Two: Good pain (why pressing on trigger points hurts like hell but feels like heaven)
3.5 Three: Tightness (why stretching is appealing but underwhelming)
3.6 Four: Weakness (why muscles with trigger points are weak and should not be challenged with strength training)
3.7 Everything we just discussed … in a few bullet points
3.8 Triggers for trigger points: what makes patches of sarcomeres go haywire?
3.9 The all-powerful acne analogy
3.10 The evolution of muscle pain: does muscle “burn out”?
3.11 Referred Pain Science (basic)
•3.12 Referred pain science (advanced)
3.13 Other trigger point theories
3.14 Quintner: “It’s the nerves, stupid”
3.15 “The bamboo cage” — what immobilization torture can tell us about the nature of muscle pain and massage
3.16 Case study: an example of getting unstuck and feeling “giddy with joy”
3.17 Muscle knots are not inflammatory: the myth of the inflamed myofascial trigger point
3.18 Adhesions and contracture: when trigger points freeze in place
3.19 The science of adhesions: atoms stick to each other
3.20 The scar tissue issue — are you scarred for life?
4 Basic Trigger Point Self-Treatment What can you do about garden variety trigger points?
4.1 Downloadable quick reference guide
4.2 Basic self-massage instructions
4.3 How do you know it’s working? Getting a trigger point to “release”
4.4 Basic tips and tricks for better, longer-lasting trigger point release
4.5 Top 5 mistakes beginners make
4.6 What about massage tools?
4.7 Can you damage your nerves when self-massaging?
4.8 Don’t hesitate to recruit amateur help
4.9 A little more perspective on amateur assistance
4.10 How to get adequate professional help
4.11 Common medications that might make a difference (and might not)
5 Advanced Trigger Point Troubleshooting What can you do about severe and persistent trigger points?
5.1 A brief detour: why not The Trigger Point Therapy Workbook?
5.2 Fundamental limitations of trigger point therapy, and how to take advantage of them
5.3 Several more treatment mistakes and problems (that you can fix)
5.4 More serious barriers to success
5.5 New evidence that squishing trigger points works at least a little
5.6 Upgrade your self-massage technique
5.7 Don’t get hung up on anatomy, and be persistent
5.8 Focussing on one trouble spot versus “a little bit of everything” — which is the better strategy?
5.9 More information about exactly how to rub (moving strokes)
5.10 Yet more information about exactly how to rub (pressing and holding)
5.11 Using “press and hold” to identify a trigger point release in progress
5.12 Identifying your trigger points by feel (once again, as it pertains to treatment)
5.13 Referred pain is not a diagnostic feature of trigger points!
5.14 Don’t be fooled by “reverse referral”
5.15 Beyond the tennis ball: commercial massage tools
5.16 Commercial massage tools to avoid
•5.17 Massage tools: 7 free (or very cheap) and tools from objects not originally intended for massage
5.18 The sock trick
5.19 The bath trick
5.20 Introduction to non-massage self-treatments for trigger points
5.21 Stretching (executive summary)
5.22 Mobilizations: massaging with movement and the Goldilocks zone
5.23 Case study: mobilizations prove to be crucial factor in recovery from neck pain that started in the 1970s
5.24 Trying to squirm your way out of trigger point pain? Don’t do it! Consider a little more method in your madness
5.25 How to take your trigger points to the gym (if you must)
5.27 Breathing deeply is free, safe, and possibly amazing therapy for trigger points
5.28 Neutral positioning: find a comfortable muscle length and rest there
5.29 An introduction to medicating muscle pain (hint: not a great option)
5.30 Anti-inflammatories and Tylenol
5.31 Voltaren® Gel, an intriguing new option
•5.32 The nuclear option: “Hillbilly heroin” (Oxycontin), codeine and other opioids
5.33 The surprising futility of muscle relaxants such as Robax-whatever, Valium and other benzodiazepines
•5.34 Lidocaine patches
5.35 Combination treatments: why and how to throw everything at it but the kitchen sink
5.36 Troubleshooting referred pain: the referred pain field guide
5.37 Case study: referred pain causes a “heart attack” and completely fools dozens of professionals
5.38 Troubleshooting negative reactions to treatment
6 Perpetuating Factors What makes trigger points stubborn?
6.1 Troubleshooting “stuck” trigger points — adhesions and contracture
6.2 Troubleshooting stress (without meditation or yoga, unless you like that sort of thing)
6.3 Troubleshooting posture, ergonomics, and muscle imbalance
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This document and all of PainScience.com was, for many years, created in my so-called “spare time” and with a lot of assistance from family and friends. Undying thanks to my wife, Kimberly, for countless indulgences large and small, and for being my “editor girlfriend”; to my parents for (possibly blind) faith in me, and much copyediting; and to Mike Gobbi, buddy and digital mentor, for many of the nifty features of this document (hidden and obvious). And thanks to all of the above, and many others, for many (many) answers to “what do you think of this?” emails.
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Regular updates are a key feature of PainScience.com tutorials. As new science and information becomes available, I upgrade them, and the most recent version is always automatically available to customers. Unlike regular books, and even e-books (which can be obsolete by the time they are published, and can go years between editions) this document is updated at least once every three months and often much more. I also log updates, making it easy for readers to see what’s changed. This tutorial has gotten 22 major and minor updates since I started logging carefully in late 2009 (plus countless minor tweaks and touch-ups).
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Major update () — Major improvements to the table of contents, and the display of information about updates like this one. Sections now have numbers for easier reference and bookmarking. The structure of the document has really been cleaned up in general, making it significantly easier for me to update the tutorial — which will translate into more good content for readers. Care for more detail? Really? Here’s the full announcement.
You can get a rough measure of how well-studied a subject is by doing a search for it on PubMed, a large database of citations to medical research. Searching for muscle strain is a bit tricky, because “muscle strain” is mentioned in lots of papers that aren’t really about muscle strain. But if you cleverly search for the terms “muscle strain” only in titles, you will get, as of 4/14/07, only 61 search results, even less than iliotibial band syndrome (another under-studied condition). Compare that to, say, 3000 for adhesive capsulitis (frozen shoulder), or 5900 for carpal tunnel syndrome. BACK TO TEXT
Strain and sprain are confusingly similar words for quite different things. They both refer to tearing, but of different tissues. A torn ligament is always called a sprain. A torn muscle is always called a strain. BACK TO TEXT
Was it really the electrolytes? No. That’s what I thought at the time, but a nice myth-busting 2011 experiment comparing crampy runners with their uncramped comrades showed clearly that dehydration was not the culprit. Fun science. See Schwellnus et al. BACK TO TEXT
Mild strains can come on relatively slowly. I have experienced at least two “slow” muscle tears of my left quadriceps while playing ultimate (a hard-running Frisbee sport). I recall in each case that there was definitely a moment of injury — but it was kind of a long, drawn-out moment. I stumbled a little. There was some pain, but not enough to stop me at first. As I kept running, though, it became clear that I was going to be benched. I had torn a few fibres, perhaps, and I was tearing more as I ran — a slow rip, a few more fibres with every step. The sense of impending doom was very strong! So, in this case, the onset was not exactly a “sudden” attack of serious pain, but it was still a perfectly clear, well-defined, can’t-miss-it kind of event. BACK TO TEXT
Example: if you rupture your Achilles tendon, you lose nearly all of your ankle plantarflexion strength. The only muscles pulling on the back of the heel are the gastrocnemius and soleus, which make up almost all the bulk of the calf, and all that strength is funeled into the Achilles tendon. BACK TO TEXT
Imagine you’re a tough athlete, like the guy in the cited case study, a mixed martial arts fighter! How do you feel if you lose about one third of the strength in your hamstrings? You know something’s wrong, for sure … but you’re tough, so you probably don’t make all that much of it. “Doc, I hurt something and I don’t think I’d want to fight right now, but I can still walk around fine.” You don’t need anywhere close to full strength most of the time… so being 30-40% short is really not that big a deal. BACK TO TEXT
There are 36 more footnotes in the full version of this book. I like footnotes, and I try to have fun with them.