Exercise is the closest thing there is to a miracle drug,12 and strength training is one of the best kinds of exercise, practically like magic: more healthy and more efficient than most people realize, and a valuable component of fitness and most injury rehabilitation, but not just for the reasons most patients and professionals think. It is the gym-o-centric, load-bearing exercise that mostly guys like to do — bodybuilding, pumping iron, powerlifting. Nearly everyone else ignores strength training, except during occasional New Year’s resolution phases, or when prescribed and/or supervised by a physical therapist.
Please don’t dismiss it! In this article, I will spell out why strength training really matters to ordinary folks, and how to do it.
While I hope anyone who’s ever spent time in a gym will find this helpful, it’s especially written for people with chronic pain and stubborn injuries who are wondering: Where does strength training fit in to a recovery plan?
The best (and least advertised) benefits of strength training
Over the years, I have come to love strength training for fitness and rehabilitation, but not for entirely conventional reasons, some of which are useless or problematic (the classic example is core strengthening, covered below). Fortunately, there are other great reasons to challenge your muscles:
- It’s more efficient and easier than most people realize, requiring less of a commitment. This particularly surprising point is covered in great detail in a separate article. It also has more lasting benefits than most people realize — permanently improved muscle cells!3
- It’s much better for general fitness, health, and weight loss than most people realize, and specifically it can partially replace so-called “cardio” workouts, which are highly repetitive and time-consuming and are a risk for all of the common repetitive strain injuries (RSIs like iliotibial band syndrome, plantar fasciitis, shin splints and several more). For instance, it’s “essential” for people with diabetes, because there’s evidence it controls blood sugar more easily than aerobic workouts (and certainly at least as well).4
- Strength training can be done safely and precisely, particularly aided by machines, so that you can pursue fitness without aggravating existing injuries or risking new ones — a critical rehabilitation advantage that is under-rated or missed entirely by nearly all professionals. Even many personal trainers fail to emphasize this!
Nothing’s perfect, of course. It is possible to hurt yourself or aggravate an existing condition, and I review the caveats below in detail. But, mostly, you “can’t go wrong getting strong.”
A replacement for joint-bashing “cardio”
Contrary to the conventional wisdom, strength training is just as good for general fitness and weight loss as aerobic exercise.5 Most people believe — ever since the “aerobics” fad in the 80s — that you have to train the heart to get in shape, and you can only train the heart with cardio, but it’s not true: it is primarily skeletal muscles that adapt to all kinds of exercise, get more metabolically efficient, do more with less oxygen and nutrients, and then demand less from the heart.6
So muscle substantially defines fitness, and therefore considerable fitness can be achieved with strength training alone — and without the drudgery of relentless cardio workouts, and without their injury and re-injury risks. Such workouts — especially running, cycling, and swimming — are brutal on joints and tendons by nature. The risk of repetitive strain injuries are baked right into them! Strength training can keep you in shape, while also giving severely fatigued anatomy a badly needed rest — rest which is the single most important factor in rehabilitation from many of the world’s most common injuries.
By all means, if you are a serious runner, cyclist or swimmer, resume your sport as soon as you can — for the love of it, and for the fitness, because those sports certainly also are good for muscle! But strength training is a valuable and effective substitute, because sometimes you just have to take a break to heal.
Doing “cardio” exercise for its own sake may be a worst case scenario: tediously slaving away on the stationary bike or Stair Master at the gym thinking that you are doing it for your heart, when all you’re really doing is eating up your day and grinding away at your joints, inefficiently training muscles that could be trained more efficiently and more safely by moving over to the weight machines.
I’m not saying cardio is useless — that would be a rather controversial claim, and hard to support with evidence! But I am saying that it has known and obvious risks, and meanwhile strength training is quite under-rated.
Some quick definitions
Strength training is the only method of building muscle mass and strength, and it is the final, logical step in a progression of rehabilitative exercise intensity. Rehabilitation is all about breaking recovery down into “baby steps.” For the severely injured, the first step is the easiest of all possible exercises: simply moving. After that, mobilizing and stretching: slow, rhythmic, gentle tissue challenges. Then comes some endurance training: lower load, higher reps, just to get comfortable with loaded movements again. And — when you are almost completely recovered already — strength training is an ideal final step.
|Mobilize!||25–75||light, very easy|
|Strength Training||6–12||moderate to high|
Fun fact: for the first few weeks of regular strength training, any strength gains you experience are mostly due to simply learning how to actually contract the muscle you are exercising (“recruitment”). Only after a few weeks of sustained training do your muscle cells start to get bigger (not more numerous), a process called “hypertrophy.”
How it’s done
The physiological changes associated with strength training occur when you exhaust a muscle within a minute or two.7 If you’re not doing this, you might be doing something worthwhile, but it’s not strength training (or not the most efficient strength training).
When you’re training, you can either count repetitions or just go for as long as you can. I prefer the latter for a variety of reasons, but it’s far more common to count reps. I’ve asked for a second big wall clock in my gym, but the management is puzzled by that: I’m the only one timing my sets. Everyone else is just counting reps and doesn’t care how long the set takes.
There’s a never-ending scientific debate about how to optimize the variables for different types of people and different goals by fine tuning the number of sets, the length of the break between sets, the number of workouts per week, and so on — although the last of those, frequency, is quite settled down now. (Hint: less than almost everyone else assumes.)
Regardless, there are going to be individual differences for everyone — evidence strongly suggests that some people, for instance, are literally genetically incapable of strength training!8 — but most people will be just fine with the dials set like so:
- only a few key exercises per workout
- 1–2 sets per exercise
- sets separated by a couple minutes rest
- each set lifting about as much as you can keep in the air for a couple seconds, or 10–20 slow- to medium-speed repetitions per set
- about a week of rest between workouts (see below)
What’s this about “exhaustion”?
It’s true, you will be tired after strength training — quite whipped! — but “exhaustion” has a more technical meaning in strength training. Exhausting muscle tissue, or taking it to “failure,” is essential for building strength.
Good, consistent exercise form is crucial in strength training not just because it’s safer — it is the simplest, best way of judging both exhaustion and progress. You know you’ve “exhausted” a muscle when you cannot repeat a contraction without losing good form. And exhaustion is exhaustion: it doesn't matter whether you get there by repeating an easier lift more, or doing a harder one a few times.
If you shake or wobble significantly and can’t stop it, you’ve lost form. If you can’t actually perform the action without squirming into a different position, you’ve lost form. If you can’t do it without bringing in a bunch of other muscles to “pinch hit,” you’ve lost your form.
And, of course, if you start doing fifteen repetitions instead of just twelve before you lose your form … you know you’re getting stronger!
Exhausting muscles requires recovery. How much recovery? How long should you wait before doing the next set?
Less is not less: strength training does not have to be as frequent as you thought!
Most people assume that you have to train muscles at least twice a week to make them stronger, and probably three times per week.
Believe it or not, scientists are actually pretty much unanimous in their agreement about this. In the last twenty years of research, there is barely a single dissenting note! Strange, I know. Exercise science is usually more controversial.
A lot of people are skeptical about this, and should be. But I have an entire article devoted to summarizing the research. If you doubt my word, please check for yourself: nine key scientific papers between 1988 and 2007 are cited, all showing clear evidence that most people can probably reduce their training frequency with little or no change in result. See Strength Training Frequency.
Once or twice per week for a given muscle group is adequate for most people, and three times per week definitely has a diminishing returns problem. Depending on the variables, some people could literally triple their gym time and effort, from 1 to 3 workouts per week, and get no additional benefit. Others might get some benefit, but minimal.
Such time savings are not trivial. Particularly for patients doing strength training only because it’s important rehab, the reduced commitment is truly important — it could easily mean the difference between doing it and not doing it. This is a guess, but it may also be even more appropriate — safer — for people with injuries to take more time for recovery between workouts.
Seriously, hire a trainer
If you are serious about using strength training to bulk up or to complete a rehabilitation process, you should definitely hire a personal trainer and/or a physiotherapist. Not only is it obviously safer to use heavy weights with guidance, you will simply get better results.9
However, do beware of trainers who push too hard and think that you need more than one workout per week.
“Blowing off steam” psychologically is one of the great benefits of strength training
Endurance training is probably the king of exercising as an outlet for frustration, but it’s certainly one of the important side-benefits of strength training too — and lower loads and higher reps and moving briskly from one exercise to the next can easily crank your heart rate well up (which is probably what’s needed for this purpose). Although everyone knows that exercise is good stress management, the interesting explanation for it is not widely known. It’s actually firmly grounded in biology and science: basically, exercise simulates a reaction to a stressful emergency which then also triggers the relaxation and recovery mode that follows. Robert Sapolsky:
The stress-response is about preparing your body for an explosive burst of energy consumption right now; psychological stress is about doing all the same things to your body for no physical reason whatsoever. Exercise finally provides your body with the outlet that it was preparing for.
~ Why Zebras Don’t Get Ulcers, by Robert M Sapolsky, 255
I think this is one of those really great little “user’s manual” things to understand about our own nature. The biology of stress is all about mobilizing biology resources for intense, life-saving activity, like running like hell from a predator, or (eek) fighting one. The curse of being human is that the same emergency biology can be triggered by abstract concerns, no predators required. But stress and anxiety are still preparing us for an emergency. So go with it — act like there’s an emergency!
Bored with tedious strength training prescription? You’re not alone!
Is this you? Your physiotherapist has prescribed a long list of therapeutic exercise that you are supposed to do frequently.
Almost immediately, it’s boring — and difficult. Many of them are what I call “ear wiggling” exercises: it’s hard to contract the muscles that you are supposed to contract. Either you can hardly do the exercise at all, or you can do it but the muscles are small, and it’s weird and frustrating how quickly such a small movement becomes totally exhausting.
But it’s supposed to be hard, you rationalize. That must be the point. The fact that you can just barely lift that 2-pound weight ten times must mean you really need this.
So you keep at it.
For a while. But the problem doesn’t really get a lot better, the exercises never really seem to get much easier, and in fact — honestly — you actually feel kind of gross after most sessions, sometimes even downright worse. And there are so many of them. And there’s no end in sight.
It’s like a life sentence: it seems like you are supposed to do these exercises practically forever, especially because you’re not really getting better …
Why strength training as rehab often fails
Rehabilitative strength training probably does aid rehabilitation in many cases. For instance, two papers have shown that both strength and endurance training were effective for treating neck pain,1011 which probably proves at least this much: almost any activity is probably better than no activity. Another pair of studies from 2008 and 2010 both showed that painful shoulder muscles respond well to strength training, getting both stronger and less painful.1213
Nevertheless, physiotherapeutic strength training is probably risky. I know and hear from an awful lot of people who are still in pain, despite doing lots of this strength-o-centric rehab. What could account for this? There are at least three significant problems I can think of …
It’s not really relevant. There is a kind of simplistic mentality behind the prescription of strength training exercises — it tends to come from a bull-headed “this part isn’t working so let’s make it work, make it tougher” idea. While I appreciate a certain amount of “use it or lose it,” it’s also kind of like the cause of a headache is not the absence of Aspirin. Strength training probably isn’t the magical missing ingredient when someone is in chronic pain. Almost no one gets into much painful trouble in the first place because they were weak. Weakness is not, by and large, a cause of pain and injury.14
It’s tedious. In my experience the huge majority of people simply cannot stick to a no-end-in-sight regimen of fiddly little strength training exercises. When physiotherapists prescribe large batches of these things, they are simply not coming to terms with the realities of human psychology. In medical science, this is the difference between "efficacy" and "effectiveness": how things work in theory versus practice.15
Too much, too soon. There are some ways that strength training can backfire, some that are inevitable, but most are easily avoided by staying in the Goldilocks zone … and encountered regularly when you don’t, which happens all too often, especially due to overzealous coaching and encouragement from personal trainers and physical therapists. I will review many of the specific ways that things can go wrong below, but the point here is just that it can go wrong, and it may not be an overt backfire: often it just subtly sabotages progress, prevents it from doing any real good.
And so I’ve known many clients and readers in various stages of disillusionment about their physiotherapy exercises. I almost never have to tell them to stop — most of them already have — just to stop feeling bad about it.
Finding the right balance between too much and too little is a theme that runs through all my articles about therapeutic exercise.
Strengthening your core to no avail!
Probably the ultimate example of therapeutically irrelevant strength training is trying to treat/prevent back pain by strengthening your “core” — muscles around the pelvis, lower back, and abdomen.
Your back hurts. You are generally healthy but, dammit, your back really hurts — and why is that, anyway? You’re generally fit. You take care of yourself. You can’t possibly be a weakling.
You don’t trust doctors with your back (which is smart, you shouldn’t16), and in fact you’re not that keen on seeking help for this kind of thing in general. You’re independent, competent, so you take matters into your own hands. Back hurts? Exercise it.
You’ve heard lots of about core stability. That has got to be important for your back. “Core stability” just sounds so good — cores should be stable, right? So it’s off to the gym.
But your results range from underwhelming17 to making a bad situation worse. A few of you will get good results. But several will also end up in pain thinking “What was I thinking?” And most simply won’t get any clear results at well. You will feel exhausted, old, vulnerable … discouraged.18
“You can’t go wrong getting strong” … or can you? The hazards of strength training
Many independent, motivated people in pain will go to the gym hoping to train their pain away, only to discover that it isn’t quite that easy. Some succeed, others fail. Some of them actually get hurt instead.
Maybe they heard that “you can’t go wrong getting strong.” The idea that strengthening is almost perfectly risk free is a surprisingly popular, naive concept in rehab and chronic pain treatment. There’s certainly truth in it, probably more than just a kernel but I think it’s wrong a little too often for comfort. That clever rhyme may not be a great thing to tell a lot of patients.
Most risks of strength training go away if you just add one critical caveat to that expression: “You can’t go wrong getting strong … with good load management.” Keep the intensity in the Goldilocks zone, no big spikes in intensity, don’t rush it, and most of what can might go wrong probably won’t.
There are certainly some pathologies where resistance training is just a bad idea no matter what, but those are mostly irrelevant in the context of typical musculoskeletal medicine. When it comes to working with “aches n pains,” there’s is almost no such thing as “going wrong” with strength training if you don’t go too far, too fast. But if you do? With poor load management, you can go wrong strength training quite easily. And of course a lot of people do overdo it, for many reasons.
And so we have a theory versus practice problem here that probably accounts for a wide range of opinions on this:19 if you assume sensible dosing and competent coaching, then it really is hard to go wrong; if you focus on the prevalence of amateurish training “in the wild,” then going wrong is all too likely.
Exactly what can go wrong with strength training
This is a list of specific examples of how strengthening can go significantly wrong without exercising extra caution, which is unfortunately rare in practice.
- Direct, simple injury has to be at the top of this list. It’s not as common as people fear — powerlifting is amazingly safe for backs, for instance — but it’s not exactly rare either. Bad things can happen when you are moving around heavy things. But this list is more about the non-obvious possibilities …
- Misdiagnosis is a large category of ways that strength training can go wrong. Some problems that appear to be “simple” musculoskeletal problems, like back pain, actually have medical causes, some of them ominous, such as pain caused by a tumour, or a drug side effect. The failure to diagnose such things correctly can lead to prescriptions of completely ineffective or harmful strength training. Here’s just a few key examples, and there are probably dozens more (because there are so many surprising ways to hurt:
- While training to look the part of Spartacus, actor Andy Whitfield pushed through a lot of back pain, assuming it was a normal reation to the intense training, but it was actually a cancer that killed him a few months later. Such scary causes of back pain (and other pain) are rare, but not rare enough — the possibility should not be ignored. A benign back tumour tormented a personal friend of mine, pressing on a nerve, for about five years before it was diagnosed. During that time, he tried strength training a couple times, with predictable, miserable results … and then he was decisively cured by surgery.
- Another “tumour”: One of my readers had runner’s knee (iliotibial band syndrome) caused by a benign cyst stuck under his IT band like a rock in a shoe: good luck treating that with strength! All you’re going to do is piss it off.
- Hypermobility (hypermobility spectrum disorders and Ehlers–Danlos syndrome) is usually caused by complex genetic defects that have poorly understood effects on muscle and connective tissue. Patients are often chronically sore and suffer from a parade of miscellaneous “unrelated” musculoskeletal problems that can go undiagnosed for years, even a lifetime. It’s possible that strength training is doomed to backfire with these patients. Or perhaps they need strength training more than anyone? But only with much greater caution than average, and probably much more than they are likely to suspect the need for.
- Chronic fatigue syndrome (unexplained fatigue, also often overlapping with chronic pain, which is why I’m including it here): these patients may seem like ideal candidates for exercise therapy, but if the cause of the fatigue is myalgic encephalomyelitis — a nasty infectious neurological disease that routinely evades diagnosis — exercising can backfire severely,20 and might even make the condition permanently worse.21
- Facioscapulohumeral muscular dystrophy (FSHD) is common and usually fairly mild form of muscular dystrophy that can cause only mild symptoms for decades, including and especially weakness, soreness, and chronic musculoskeletal complaints … exactly the kind of trouble for which strengthening is often prescribed! And it might help mitigate the problem, but patients will certainly be much more vulnerable to exercise overdose, and of course their problems cannot actually be solved by strength training.
- Frozen shoulder can get severely exacerbated by any attempt at strength training, no matter how careful. This condition can even flare up badly even just with range of motion exercises.
- Neuropathies — pain caused by trouble with nerve tissue — of all kinds can be seriously exacerbated by resistance training. It’s important to note that these conditions are often surprisingly subtle and undiagnosed, but misdiagnosis probably isn’t the main problem: it’s underestimating their vulnerability to exercise therapy in general and strength training in particular.
- Chronic achilles tendinopathy is prone to rupture, and can be triggered by rehabilitative strength training, especially rapid loading (eg plyometrics). While carefully managed eccentric loading might be therapeutic, it’s not totally clear, and exactly how much load these tendons can handle without breaking is largely unknowable.
- Repetitive strain injuries can occur because of natural vulnerability to relatively normal loading — not “overuse” — and anything less than extraordinary caution with dosing might make it worse. Patellofemoral pain is the canonical example: that joint is naturally biomechanically extreme, and can get overloaded even with very average use.
- Sensitization often involves greatly reduced load tolerance … so much so that even cautious resistance training is ineffective at least, hazardous at worst. Since sensitization is probably a factor in most stubborn injuries, this is highly relevant to a lot of rehab, especially for the worst cases. Chronic widespread pain is related to sensitization (lots of overlap), may eventually benefit from building their strength, but often have such poor load tolerance that they just can’t handle resistance training (at first for sure, maybe never).
- Anxiety and hypervigilance. Some people are indoctrinated to believe that the point of strength training is to fix weakness (especially “core” weakness) that makes them vulnerable to injury. Belief in fragility can become a major factor in future episodes of pain, especially back pain, which is notoriously sensitive to such anxieties.22 It can also lead to a great deal of wasting time if people focus on training obscure muscles far beyond their functional needs.
- Trigger point exacerbation. The sore spots that most of us often develop in soft tissue are poorly understood, but they probably involve some vulnerability to physical stress. They may flare up if you’re not careful, even if they respond well to cautious progressive training. Ancedotally, I think quite a few “injuries” at the gym are not muscle strains (tears) but simply aggravated trigger points, which can be so acute that they feel like injuries.
Now back to the good news
Yes, there is good news! Strength training can be useful, and it can be done safely.
You should do strength training when you have already paid your dues doing easier work first. You should do it to cover that last, crucial step from “recovered” to “better than ever.” You should do it to test your tissues, to reveal remaining vulnerability, to demonstrate to yourself that you really are better. When you are ready for it, strength training is a powerful way of demanding the highest possible function from your tissues, the most potent way of “using it” instead of “losing it.” The physiological effects are significant and numerous:
- blood flow is increased far more than any massage could ever do, capillaries open up wide, the entire system mobilizes resources to supply hungry muscles with oxygen and nutrients
- metabolic waste products are produced and washed away at a prodigious rate, probably including old stale ones still lingering in the dregs of trigger points that you mostly (but not entirely) got rid of in earlier stages of recovery
- coordination and neurological function improves with every workout as you “learn” how to actually recruit a respectable number of muscle fibres, which is responsible for most early strength gains
- rusty inhibitory and excitatory reflexes are exercised, normalized, balanced, which probably provides an injury prevention benefit
And, of course, if you do enough of it you may even get some vanity benefits, hypertrophied muscle cells, “big guns,” a stomach with speed bumps. Wouldn’t that be nice?
All of this is just great … when you’re ready for it.
The psychological edge
Some people can probably benefit from the gym sooner than others, even in spite of trigger points. For a lot of people, especially guys, challenging themselves with weights has huge psychological and emotional benefits — so great that, for a certain type of person, they can outweigh the risks, even when muscles may not be quite ready for strength training.
The same can be true for anyone who has gone through a rational, well-managed rehabilitation process. If you are impatient, if you like endorphins, if you have already tested yourself with endurance training and do not feel too held back by trigger points, then you might be able to exploit strength training sooner — before other people would be considered “ready.”
Strength training can “blast through” the limitations of trigger points in such cases. I’ve seen it a few times, even experienced it occasionally. Obviously, you should not try to do this without being alert for warning signs.
Not just the gym
Of course, some people don’t like gyms. I’m one of them, actually — or used to be, anyway. You should consider trying to overcome gym shyness because (a) the people there are probably nicer than you think, (b) strength training is fairly efficient and you probably don’t need to spend as much time there as you fear, and (c) the precision and control of universal gym equipment has many advantages.
Nevertheless, there are some excellent, creative alternatives to gym training. Your own body weight can be more than adequate for strength training many large muscle groups. Slow deep knee bends, push ups, chin ups, and abdominal roll-ups are all good examples of body-weight-only exercises that many people cannot do many of — good places to start strength training without gym equipment.
However, it must be said that a thorough strength training program simply cannot be done without at least some apparatus. A small investment in a few barbells and exercise bands or tubing (large, colourful elastic bands or tubes) allows for an almost infinite number of strength training options.
Can strength training prevent overuse injuries like runner’s knee?
Repetitive strain injuries like plantar fasciitis and iliotibial band syndrome (runner’s knee) are often seen as a price that active people pay for being weak in some way. Although this has always been a popular view, it’s been given new life since the early 2000s by a lot of hype about hip weakness specifically, which supposedly causes runner’s knee (and maybe other overuse injuries in the lower body). If it’s true, then surely strength training the hips can prevent runner’s knee? Unfortunately, this is just a pet theory that got out of hand, and still isn’t supported by any credible evidence.23
A 2014 meta-analysis is the best reference available to support a more general claim that resistance training will prevent overuse injuries.24 Unfortunately, “the best” is not very good: the authors’ conclusion about injury prevention is based on data from just four studies of questionable/limited relevance …25 and there is definitely some contrary evidence as well.26
Strengthening might prevent some overuse injuries, but that’s an untested hypothesis, and Lauersen et al simply does not provide meaningful support for it—not even remotely. There are all kinds of other reasons to train your muscles. Use those reasons. You don’t need this one.
On the bright side, strength training probably can reduce the risk of tearing a muscle, an extremely common sports injury (muscle strains). It makes more sense, and there’s some evidence supporting that.27
Muscle knots are significantly involved in almost every injury or pain problem. And strength training, by definition, demands exactly the worst possible conditions for muscle knots, namely severe muscle fatigue — so please be careful when strength training. If it aggravates your symptoms or leaves you feeling drained … go back to endurance training!
But strength training is an important final step in rehabilitation for those who are ready: either when trigger points are mostly under control, or perhaps a little earlier for those who really enjoy hard exercise.
About Paul Ingraham
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.
- PS Strength Training Frequency — Less is more than enough: go to the gym less frequently but still gain strength fast enough for anyone but a bodybuilder
- PS Endurance Training for Pain & Rehab — Why endurance training might be a wise alternative to strength training (especially when healing from an injury)
- PS Mobilize! — Dynamic joint mobility drills are an alternative to stretching that “massage with movement”
- PS The Trouble with Chairs — The science of being sedentary and how much it does (or doesn’t) affect your health and back pain
- PS Micro Muscles and the Dance of the Sarcomeres — A mental picture of muscle knot physiology helps to explain four familiar features of muscle pain
Some good strength training resources around the web (mostly for readers who are pretty serious about their strength training):
- The Strength Athlete (thestrengthathlete.com). Good quality evidence-based blog, coaching, and other resources for powerlifters. A couple of articles of potential interest to PainScience.com readers:
- Strength and Conditioning Research (strengthandconditioningresearch.com). Detailed analysis of exercise science, biomechanics, and applied strength and conditioning.
- The Glute Guy (bretcontreras.com). Great writing and critical analysis of strength science… with a butt focus. 🍑
What’s new in this article?
Five updates have been logged for this article since publication (2006). All PainScience.com updates are logged to show a long term commitment to quality, accuracy, and currency. more
Like good footnotes, update logging sets PainScience.com apart from most other health websites and blogs. It’s fine print, but important fine print, in the same spirit of transparency as the editing history available for Wikipedia pages.
I log any change to articles that might be of interest to a keen reader. Complete update logging started in 2016. Prior to that, I only logged major updates for the most popular and controversial articles.
See the What’s New? page for updates to all recent site updates.
October — Minor but nice addition of a “good news” reference about the permanence of a key exercise benefit.
2018 — Added an important point about efficacy vs. effectiveness (see Beedie et al and several more examples of adverse effects of strength training.
2018 — New section: “You can’t go wrong getting strong” … or can you? Some hazards of strength training.
2018 — New section, “Can strength training prevent overuse injuries?”
2016 — Added “Why is exercise healthy?” sidebar.
2006 — Publication.
- Academy of Medical Royal Colleges. Exercise: The miracle cure and the role of the doctor in promoting it. AOMRC.org.uk. 2015 Feb. PainSci #53672. ❐
This is the primary authoritative source of the quote “exercise is the closest thing there is to a miracle cure.”BACK TO TEXT
- Gopinath B, Kifley A, Flood VM, Mitchell P. Physical Activity as a Determinant of Successful Aging over Ten Years. Sci Rep. 2018 Jul;8(1):10522. PubMed #30002462. ❐ PainSci #53004. ❐
If you want to age well, move around a lot!
We already know that physical activity reduces the risk of several of the major chronic diseases and increases lifespan. “Successful aging” is a broader concept, harder to measure, which encompasses not only a reduced risk of disease but also the absence of “depressive symptoms, disability, cognitive impairment, respiratory symptoms and systemic conditions.” (No doubt disability from pain is part of that equation.)
In this study of 1584 older Australians, 249 “aged successfully” over ten years. The most active Aussies, “well above the current recommended level,” were twice as likely to be in that group. Imagine how much better they’ll do over 20 years …<#comments#> BACK TO TEXT
- Schwartz LM. Skeletal Muscles Do Not Undergo Apoptosis During Either Atrophy or Programmed Cell Death-Revisiting the Myonuclear Domain Hypothesis. Front Physiol. 2018;9:1887. PubMed #30740060. ❐ PainSci #52684. ❐
Why is it easier to get back in shape than it is to get into shape in the first place? Some adaptations to muscle training are temporary and vanish quickly if you don't keep working out. But others, like the addition of extra muscle nuclei, appear to be more or less permanent. Nuclei are added as you train so that they can build and manage more proteins in a plumper muscle cell. When you stop training, the cell slowly deflates — atrophies — but the nuclei helpfully remain, dormant, waiting until you are ready to exercise again. See Alex Hutchinon’s more detailed analysis of the study.BACK TO TEXT
- Codella R, Ialacqua M, Terruzzi I, Luzi L. May the force be with you: why resistance training is essential for subjects with type 2 diabetes mellitus without complications. Endocrine. 2018 May. PubMed #29730785. ❐
Dr. Brad Schoenfeld‘s comment on the study: “The title says it all. Many modalities of exercise are beneficial, but resistance training is the most important activity you can do for overall health and wellness. 💪🏻”From the abstract:
Anaerobic, intense physical activity, such as that of strength or power sports disciplines, is not univocally recognized as safe and simple to realize, however, it is important in stimulating energy and glucose metabolism. According to recent evidence, high-intensity training may be prescribed even in the face of cardiovascular diseases, peripheral vascular disease, or osteoarthritis. Some studies have shown resistance training to be more efficient than aerobic exercise in improving glycemic control. This review explores the most up-to-date indications emerging from literature in support of the beneficial effects of strength stimulation and resistance training in patients with type 2 diabetes without complications.
- Clark JE. Diet, exercise or diet with exercise: comparing the effectiveness of treatment options for weight-loss and changes in fitness for adults (18-65 years old) who are overfat, or obese; systematic review and meta-analysis. J Diabetes Metab Disord. 2015;14:31. PubMed #25973403. ❐ PainSci #54044. ❐
Resistance training is an excellent method of improving body composition (ratio of muscle to fat) and markers of health (risk of cardiovascular disease). This meta-analyis concluded that weight-loss methods “utilizing exercise were more effective than those that employed just a hypocaloric diet,” and that combining diet with resistance training (weight lifting) was specifically more effective than combining it with endurance (aerobic) exercise. This flies in the face of the popular belief that endurance training is “heart exercise.”BACK TO TEXT
- Your heart and blood vessels themselves do not significantly adapt to any kind of training, but your muscles most definitely do. This critical point has been proven various ways, but my favourite is the experiment that trained only one leg in cylists, leaving the other leg out of shape and weak. Their aerobic fitness was great when using the trained leg, but lousy with the untrained leg: clearly, it wasn’t their hearts that changed! (Citation needed. I’m not sure why there isn’t one here. I remember the study, but cannot find it!) BACK TO TEXT
- Kisner C, Colby LA. Therapeutic exercises: foundations and techniques. 3rd ed. FA Davis Company; 1996. BACK TO TEXT
- Hubal MJ, Gordish-Dressman H, Thompson PD, et al. Variability in muscle size and strength gain after unilateral resistance training. Med Sci Sports Exerc. 2005 Jun;37(6):964–972. PubMed #15947721. ❐
This 2005 paper presents good evidence that there may be genetic differences between people that account for a surprisingly wide range of responses to strength training. In a fascinating radio interview about the paper, co-author Dr. Eric Hoffman says, “If we take two friends and enter them into a resistance training program, you could find that the one friend would trip all their muscle strength, whereas we have cases in the study of the other friend who either gains no strength, and we have some subjects that even lose a little strength.”BACK TO TEXT
- Mazzetti SA, Kraemer WJ, Volek JS, et al. The influence of direct supervision of resistance training on strength performance. Med Sci Sports Exerc. 2000 Jun;32(6):1175–1184. PubMed #10862549. ❐
From the abstract: “Directly supervised, heavy-resistance training in moderately trained men resulted in ... greater maximal strength gains compared with unsupervised training.”BACK TO TEXT
- Nikander R, Mälkiä E, Parkkari J, et al. Dose-Response Relationship of Specific Training to Reduce Chronic Neck Pain and Disability. Med Sci Sports Exerc. 2006 Dec;38(12):2068–2074. PubMed #17146312. ❐
Similar to Ylinen, researchers divided 180 female office workers with chronic neck pain into three groups: one group did strength training, another did endurance training, and a third did nothing. They found that “both strength and endurance training decreased perceived neck pain and disability.”BACK TO TEXT
- Ylinen J, Häkkinen A, Nykänen M, Kautiainen H, Takala EP. Neck muscle training in the treatment of chronic neck pain: a three-year follow-up study. Europa Medicophysica. 2007 Jun;43(2):161–9. PubMed #17525699. ❐
There are only a handful studies of long-term strength training for neck pain: two by this research group (Ylinen 2003, Ylinen 2006), plus their three-year follow-up to the first. They found that a year of regular neck strength or endurance training meaningfully reduced pain and disability. These benefits were sustained for three years in over a hundred women, even though many people didn’t continue training after the first year.
There are only a handful of other studies of exercise for neck pain, which have all failed to detect any of lasting benefit to exercise for neck pain. The results of these studies suggest that “most training studies seem to have been too short-term producing notable physiological changes.” But duration is the key, not intensity: “a relatively small training load is high enough to reduce these changes, as there was no significant difference between the strength and endurance training groups with regard to the primary outcomes,” pain and disability.
Although these results are certainly good news, it’s important to keep in mind that not all patients improved completely, and even those who did achieve lasting had to exercise diligently for a year (although six months might have done the trick, we can’t tell from this data). So strengthening is not a reliable or easy fix for neck pain (the efficacy vs. effectiveness problem strongly applies, see Beedie).BACK TO TEXT
- Andersen LL, Andersen CH, Zebis MK, et al. Effect of physical training on function of chronically painful muscles: a randomized controlled trial. J Appl Physiol. 2008 Dec;105(6):1796–801. PubMed #18948442. ❐ PainSci #54962. ❐
This simple test of strength training as therapy for shoulder pain had positive results in 42 women with shoulder pain, researchers found that “specific strength training relieved pain and increases maximal activity.” Indeed, their pain was reduced 42–49%, and this result was less than 5% likely to be due to random chance.BACK TO TEXT
- Nielsen PK, Andersen LL, Olsen HB, et al. Effect of physical training on pain sensitivity and trapezius muscle morphology. Muscle & Nerve. 2010 Jun;41(6):836–44. PubMed #20513105. ❐
In this experiment, 62 women (40 with shoulder pain, 20 without) participated in either a general exercise program or specific strength training for their shoulders. Pain tolerance and strength increased response to strength training in the women who started out with pain. In those who had no pain to begin with, both general exercise and specific exercise training were beneficial.BACK TO TEXT
- Howls of protest! But consider one of the most trendy of all strength prescriptions: hip strengthening to treat lower body injuries, because allegedly hip weakness causes them in the first place. It’s been in all the glossy running mags, and it is touted as being science-based … and yet the actual evidence is pathetic if you go looking, and the connection is definitely not clear, let alone proven. See Does Hip Strengthening Work for IT Band Syndrome? The popular “weak hips” theory is itself weak. BACK TO TEXT
- “Efficacy” is how well a treatment works in ideal circumstances, such as in a carefully contrived scientic test. Unfortunately, real life is rarely ideal! (You may have noticed.) “Effectiveness” is how well the same thing works in typical clinical settings and patients’ lives. Which is what matters to most patients. A 2015 editorial in the British Journal of Sports Medicine explains that exercise (in a physical therapy context) is well-known to be efficacious, but often is not effective. That is, it works well when tested in the lab, but not so much for real patients. Again, effectiveness is what matters to patients! If effectiveness is low, only a few lucky and/or disciplined people can realistically expect to benefit. BACK TO TEXT
- Doctors are unqualified to care properly for most common pain and injury problems, especially the stubborn ones, and this has been proven by other doctors: Stockard et al found that 82% of graduates lacked “basic competency” in this area. For more information, see The Medical Blind Spot for Aches, Pains & Injuries: Most physicians are unqualified to care for many common pain and injury problems, especially the more stubborn and tricky ones. BACK TO TEXT
- Smeets RJ, Wade D, Hidding A, et al. The association of physical deconditioning and chronic low back pain: a hypothesis-oriented systematic review. Disabil Rehabil. 2006 Jun;28(11):673–693. PubMed #16809211. ❐
This 2006 review is painfully vague about the importance of low back muscle condition in chronic low back pain. Although there is some evidence that suggests that core stability training is good for back pain (see O'Sullivan), it’s nowhere near as strong as it should be, considering how popular the concept has been for the last fifteen years. Cardiovascular training for back pain has barely been studied, and the authors found no high quality studies of that at all — and unfortunate gap. There is only a little evidence of wasting of the deep multifidus muscle (which many assume to be deconditioned in back pain, though it could easily just be a symptom of being in pain, not a cause of it). They also conclude from the available evidence that “general and lumbar muscle strengthening are equally effective as other active treatments,” and the authors believe that it is “more promising” to study “the interplay between biological, social and psychological factors.” Not exactly a resounding endorsement of going to the gym for your low back pain!BACK TO TEXT
- When I read this, it sounds like I am trying to use scare tactics to make my point, and I know that the research evidence shows that many people with low back pain do feel better when they exercise. But what can I say? I cannot ignore my own experience, subjective as it is: I’ve met a lot of clients who did not feel better for working out. A thousand things could account for the difference, starting with the fact that people who participate in scientific research are having a different experience in so many ways than the independent person training without guidance. This may be why Smeets et al. thought that it was “more promising to further explore the interplay between biological, social and psychological factors” than it was to study the connection between muscle deconditioning and low back pain. The bottom line is that the jury is out — and there is obviously something risky about going to the gym when you have low back pain. BACK TO TEXT
- I conducted informal polls on both Facebook and Twitter, and responses were quite diverse. As expected, at least some pros clearly truly believe that you literally “can’t go wrong.” BACK TO TEXT
- These waters have been muddied by the infamous “PACE” trial, a big British experiment which concluded that graded exercise therapy was helpful for myalgic encephalomyelitis patients. But the PACE trial has been tainted by scandal and harshly criticized as “uninterpretable.” There are good reasons to believe that PACE got it disastrously wrong, and exercise actually hurts ME patients: see Shepherd. BACK TO TEXT
- “We hypothesize that these crashes, or episodes of heightened fatigue, may have a cumulative effect on a patient’s health, and may compromise the patient’s potential for a full recovery.” From: Instructions for Stanford Chronic Fatigue Syndrome Patients. BACK TO TEXT
- PS Ingraham. The Mind Game in Low Back Pain: How back pain is powered by fear and loathing, and greatly helped by rational confidence. ❐ PainScience.com. 1217 words. BACK TO TEXT
- PS Ingraham. Does Hip Strengthening Work for IT Band Syndrome? The popular “weak hips” theory is itself weak. ❐ PainScience.com. 3497 words. BACK TO TEXT
- Lauersen JB, Bertelsen DM, Andersen LB. The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials. Br J Sports Med. 2014 Jun;48(11):871–7. PubMed #24100287. ❐ PainSci #53226. ❐ BACK TO TEXT
- All the 4 studies are of the lower limb, two of them about hamstrings and eccentric training, both of which have limited applicability to the question of preventing overuse injuries (most injuries of the hamstrings are not overuse injuries, and eccentric training is not typical resistance training). The third was a study of ACL injuries, which are traumatic, not overuse, so that doesn’t contribute to the case for preventing overuse injuries. And the final one was for patellofemoral pain, which does count, but its results are hardly decisive (see Coppack et al). BACK TO TEXT
- Brushøj C, Larsen K, Albrecht-Beste E, et al. Prevention of overuse injuries by a concurrent exercise program in subjects exposed to an increase in training load: a randomized controlled trial of 1020 army recruits. Am J Sports Med. 2008 Apr;36(4):663–670. PubMed #18337359. ❐ BACK TO TEXT
- Tyler TF, Schmitt BM, Nicholas SJ, McHugh MP. Rehabilitation After Hamstring-Strain Injury Emphasizing Eccentric Strengthening at Long Muscle Lengths: Results of Long-Term Follow-Up. J Sport Rehabil. 2017 Apr;26(2):131–140. PubMed #27632842. ❐ BACK TO TEXT