One winter, my hip started to hurt when I ran. Fleetingly at first, but soon the pain decided to unpack its bags and settle in. It’s hard to describe exactly where it hurt; somewhere deep inside that I couldn’t touch. Sometimes the pain was raw and intense, other times, quietly smouldering, but it was never absent.
The physio put it down to me slipping and sliding on muddy trails, told me to lay off the running and gave me some exercises to do to stretch and strengthen the surrounding muscles. But nothing – rest, massage, exercises – helped.
Days turned into weeks and I limped around miserably, picturing the inside of my hip joint like one of those telephone exchange cabinets you sometimes see open in the street – the tangled mass of wires spilling out representing the frayed muscle fibres and throbbing nerves I felt sure were there.
Eventually I forked out for an MRI and braced myself for the results. The damage? None. I was astounded. Richmond Stace, however, is not.
‘Pain is a perception,’ says Stace, a physiotherapist who specialises in dealing with pain (specialistpainphysio.com). ‘It is not bound to anything physical.’
It’s hard to get your head around the notion that the pain you are feeling in that hip, knee or foot isn’t directly caused by – and proportionate to – damage within the tissues, but experiences such as mine have been borne out in many studies, which have shown that not only can pain exist where there is no tissue damage but that tissue damage can be present without pain.
For example, in a 2005 study, MRI scans of the knees of 44 subjects suffering no pain symptoms at all revealed meniscal degeneration or tears in almost every case. Other research found that 38 per cent of asymptomatic subjects showed abnormalities (such as ‘bulging’ discs) in the lumbar spine – the sort of abnormalities that would be used to ‘explain’ pain, were pain present.
So if pain isn’t synonymous with injury, what exactly is it waving its red flag about?
No brain, no pain
Pain is a message or a ‘need state’ (like hunger or thirst), which compels protective action,’ says Stace. ‘There is a need to be met, and our attention is drawn to a particular part of the body. We must then decide whether there really is a threat or danger in the area that we’re feeling the pain, or not.’
So why, in my case, the hip, and not another part of my body? ‘The brain makes a best guess,’ explains Stace. ‘If there’s enough evidence to suggest that there ‘could’ be a problem at the hip, that is all that is needed for protection to kick in. The experience of pain has to be played out in the body.’ The threat or danger could be the result of an excessive training load, altered biomechanics or a reduction in strength rather than what we’d typically think of as an ‘injury.’
There is much research to support the contention that pain is – in every instance – a construct of the brain. As Professor Lorimer Moseley, one of the leading scientists investigating pain in humans, points out, the widespread phenomenon of phantom limb pain in amputees would not exist if pain were truly and solely representing physical damage. How can your left leg hurt if you don’t even have one? In one of Moseley’s experiments, people who had a prosthetic limb arranged in front of them as if it were their own experienced pain when that leg was attacked.
However, it’s important to stress that while pain is produced by the brain and not the body, it does not mean that tissue damage – or the pain arising from it – isn’t real.
‘It is real, but the relationship is complicated,’ says Paul Ingraham, pain educator and creator of the online resource Pain Science (painscience.com).
Modern pain science is based on what’s known as the biopsychosocial model – which takes into account the biological, psychological and social factors affecting our experience of pain. ‘It doesn’t imply that there are no physical factors, but how it differs from the traditional view is that it recognises injury and pain are not in lockstep with each other,’ says Ingraham. ‘That is what nearly everyone assumed for a long time. And many professionals, even though they know better, often seem to forget how powerfully pain is influenced by perception.’
Stace agrees. ‘Looking for a purely physical solution for pain tends to result in poorer outcomes. We have to remember it’s a whole person who experiences pain, not a body part.’ He offers an analogy: Imagine you are at the cinema and the screen suddenly goes blank. The attendant comes in and shakes the screen. ‘Does that help restore the film? No. The problem isn’t with the screen, it’s elsewhere. No matter how many times, or how vigorously, you shake the screen it’s not going to help.’
Regardless of whether the pain you are feeling in your knee is a result of some damage there (what Ingraham calls a ‘tissue issue’) or not, its intensity can be greatly influenced by your state of mind including mood, stress levels and, says Tom Goom, a physiotherapist who specialising in treating runners (running-physio.com), thoughts about the pain itself and what it means.
The agony of not running
‘For many – if not most – runners, the sport goes far beyond being a form of exercise,’ says Goom. It’s woven into the fabric of our very lives. It’s our social network, our stress relief and our arena for experiencing mastery, enjoyment and a sense of purpose and belonging. Losing it, therefore, is a big deal, creating a great deal of stress and anxiety, which, in turn, can magnify the pain experience.
A study on violin players offers a neat example of this in the real world. Researchers found that the musicians’ ‘playing’ hands had greater sensitivity to pain than their non-playing hands, simply because of the importance attached to the former.
‘If running forms a large part of your social life, it’s important to stay involved in other ways if you can’t run, rather than isolating yourself,’ says Goom. Perhaps you could still go to the clubhouse to do your rehab exercises, participate in the warm-up and cooldown or get involved with volunteering – such as timing on the track or even making the tea. (Being a coach was a godsend for me, enabling me to experience fulfilment through others’ success.) Many studies have shown that positive mood states (contentment, calm, joy) can reduce pain sensitivity. But, says Greg Lehman, a physiotherapist who specialises in applying pain science to biomechanics (greglehman.ca), the pain-mental state connection works both ways. ‘Irrational or disproportional beliefs and deep feelings of worry or fear (known respectively as catastrophising and rumination) can intensify pain,’ he says. A study in 2018 found that high levels of emotional distress, anxiety and fear-avoidance were associated with greater levels of pain.
Even the healing process itself can be affected by external factors. ‘Sensitising factors like stress and sleep deprivation can cause normal injuries to hurt sooner, worse and longer,’ says Ingraham. A study at Kings College, London found that elevated levels of the stress hormone cortisol slowed healing. If this isn’t a cruel twist of fate, I don’t know what is. You love running, you start to experience pain when you run and therefore have to stop temporarily – but the distress you feel about having to stop not only intensifies the pain but may also make it last for longer.
To be honest, I think I would find the idea that my mental status can adjust the pain- intensity dial farfetched if I didn’t have personal experience of it. In that year of my hip injury, my dad was dying of a brain tumour. In the final days of his life, we gathered around his bedside, sharing memories through tears and laughter as he slipped in and out of consciousness. My hip was so stiff I limped each time I stood up to walk and at night, it throbbed unbearably if I lay on my side. Yet a week after his suffering ended, I ran a 10K with no pain at all. It wasn’t the end of the injury, but it offers a snapshot of how pain – and even function – can be modulated by seemingly unconnected things.
‘It’s important to remember that the brain does not have actual access to the body,’ says Stace. ‘It only receives signals, from which it infers what’s going on and creates a perception.’ In the biopsychosocial model of pain, the accuracy of this perception is based on all the things we ‘bring’ to our experience of pain.
‘What do you need to have knee pain?’ Stace asks me. ‘A knee,’ I quip. ‘Yes, and what else?’ ‘A brain?’ ‘Yes, and a nervous system, an ego, a history… all of these will be used by the brain in its assessment of how to respond to the signals it receives.’
When it comes to running injuries, one of the most significant factors in shaping that response is previous experience of injury.
Injury begets injury
‘“Once burned, twice shy” is a very basic pain principle,’ says Ingraham. ‘The brain remembers and the brain is paranoid, so a runner’s second case of IT band syndrome or plantar fasciitis, or whatever, kicks in at a lower threshold. They think they’ve overloaded the tissue again, but the chances are that load is much less of a factor this time round: still a factor, just no longer the only one. And the more they get reinjured, the more this is true.’
I can relate to this. Since my hip injury, I seem to have an over-zealous hard-hatted health and safety officer lurking in my brain – ready to leap into action at the merest inkling of pain.
Given that the most common predictor of a running injury is a previous injury, it’s intriguing to wonder whether this is a result not of faulty biomechanics but of a brain primed by past experience to overamplify pain.
So how do we break free from this vicious circle?
‘The first step is to find out what’s going on,’ says Lehman. A thorough assessment by a physiotherapist or osteopath who specialises in chronic pain or pain management (physios may be registered with the Physiotherapy Pain Association, a division of the Society of Chartered Physiotherapists) will ascertain if there are physical factors contributing to your pain – helping you make a decision about how to proceed. ‘You need to know if the pain is something sinister, whether it requires a specific fix (such as a ligament tear), means you need to rest or back off – or whether continuing with the activities that are meaningful to you is ultimately more helpful,’ says Lehman. For example, a runner could have tendinopathy that seems related to pain. ‘They will certainly want to modify their training and perhaps add exercises to address the tendon, but they could also keep running with a little bit of discomfort. It’s important to understand that some pain and niggles are normal when you are training.’
From a purely physical point of view, the idea of running through pain sounds like bad advice. But increasingly, pain science is steering us away from the ‘rest is best’ protocol, which could unwittingly be reinforcing the brain’s perception that there’s ‘something bad’ going on in the body that needs protection. ‘Provided serious pathology has been ruled out, most people can keep running or walking to some degree with most injuries,’ says Lehman. ‘In my opinion, keeping up activities that are important and meaningful to you is one of the keys to good rehab.’
Research has shown that isometric exercises (where you contract a muscle without moving it) can give immediate pain relief in cases of patellar and Achilles tendinopathy. ‘Actually, almost any type of exercise seems to modulate the tissue irritation signals that get sent from the body,’ says Lehman. Stace agrees. ‘Pure rest won’t help in instances of chronic and persistent pain, because nothing has changed when you go back to exercise. Motion is lotion.’
So where does all this leave the traditional go-to therapies we runners turn to when we’re addressing pain and injuries, such as deep-tissue massage, muscle energy techniques and foam rolling?
‘These approaches may have a small, short-term effect on reducing pain,’ says Goom. ‘They’re not great long-term strategies, however, and can aggravate symptoms in some patients. One concern is that we can become dependent on them, rather than looking for long-term solutions. For that reason, they usually work best as an ‘adjunct’ to more active management of pain (exercise, education, lifestyle change).’
Don’t take any of this to mean that you should continue blindly with your training schedule in the face of pain and possible tissue damage. It comes back to Lehman’s point about finding out where you stand – and recognising that you cannot assume that the extent – or even the presence – of pain is a true reflection of what is going on in your body.
There are, however, likely to be some clues. If you fell down a rabbit hole a couple of days ago and wrenched your ankle, for example, you probably can make a logical connection between the injury and pain you’re suffering: ‘Simple pain experiences are usually exactly what they seem to be,’ says Ingraham. ‘By “simple” I mean in a specific anatomical location, affected by position and movement, with a clear relationship with trauma or loading.’ This kind of ‘acute’ pain tends to correlate well with tissue damage (although your experience of it can still be modulated by other factors). But when pain persists long after body structures should theoretically have healed, things get more complex.
When pain won’t switch off
In the research, chronic pain is defined as pain that lasts or recurs for three to six months. In essence, it refers to any ongoing pain that cannot – or at least, can no longer – be explained by those ‘tissue issues.’
If you’ve reached a point, weeks after an injury, where you’re thinking – But it still hurts! There must be something wrong even though you’ve been assured there is no major damage, the problem is most likely not with your body but with your central nervous system. ‘This ‘central sensitisation’ can cause even a trivial tissue issue to cause disproportionately intense pain,’ says Ingraham.
Lehman likens the response to a smoke alarm. ‘A smoke alarm doesn’t tell us how much smoke there is – it can go off even when there is no smoke at all and continue to go off after the fire has been put out.’
Research has shown that highly sensitised pain sufferers can experience ‘anticipatory’ pain even before a stimulus is applied (such as ‘feeling’ the pain of an injection before the needle has touched the skin) as well as a heightened or disproportionate response, known as hyperalgesia, to mild pain stimuli and even completely benign ones, like touch.
Let’s say you’ve been battling plantar fasciitis for many months and have only just got back to running. ‘Even as you put on your shoes, your brain is pondering ‘is this safe?’ says Stace. ‘If you should then be unlucky enough to step on a stone, you are quite likely to feel a disproportionately intense pain, because the brain is simply fulfilling the response that it predicted.’
Once sensitisation occurs, the challenge is to retrain the brain to understand that movement is safe. It’s the equivalent of getting the smoke alarm to only go off when there is sufficient smoke around to be a cause of concern (and stop as soon as it has dissipated).
‘Athletes and therapists tend to regard rehabilitation as a process of physical adaptation – of changing tissue state – but the longer you’ve had the problem the more likely it is to be about neurology,’ believes Ingraham. ‘If you’ve reached a stage where you suspect that your nervous system is no longer giving you useful, sensible pain signals be extra cautious about painful manual therapies and sceptical of biomechanical explanations for your pain (“you’ve got one leg shorter than the other”). Such factors are only part of the picture, and probably the least important part. A better focus is on desensitising and teaching the central nervous system that it’s OK to use that anatomy again.’ To return to our plantar fasciitis example, you might start by seeing if you can stand on one leg without pain and if so, can you rise up on to the toes? How about jogging a few steps on the spot? Still pain-free? Great – can you run for 20 seconds without pain? A minute? By finding out what you can do without pain, you can begin to move (run) within that comfortable range – and as the brain dials down the alarm system, this range will gradually get bigger. ‘When you’re first getting back to running, picture yourself running fluidly and comfortably for a minute or so before you actually go out, to create a positive mindset,’ suggests Stace.
The new pain science doesn’t set out to suggest that pain – even unexplained pain – isn’t real, or that it’s ‘all in your head’. But it does free us from looking at injuries – especially long-standing and recurring ones – solely as tissue issues, widening the scope of what we can do about them. Alongside our rehab exercises, we may need to consider our beliefs about running, our lifestyle and our overall mental and physical health.
Knowing that there wasn’t any sign of damage in my hip joint certainly helped get me on the road to recovery. It didn’t change anything physically (it still hurt) but it made a difference mentally because it freed me from two huge fears: one, that I was ‘finished’ and would never run pain-free again; and two, that by returning to running I might cause further damage.
It took that change in mindset – and finding a physiotherapist who I believed in (I broke down in tears in his office when he told me ‘we’ve got some work to do but we’ll soon have you running again’) – to get me moving along that road. These days, I can even run past telephone exchange cabinets without a second glance.
Six Steps to Making Your Rehab Successful
- Be focused.
Don’t rush through your rehab exercises when you’re about to go to work or do it mindlessly in front of the TV. ‘Set yourself up properly and allow enough time to do it well,’ says Stace. ‘Five really good reps are better than multiple bad ones.’ A 2012 study in the British Journal of Sports Medicine found that a negative attitude to rehab was associated with a poorer success rate concerning return to sport. - Break your rehab sessions into bouts.
‘This creates lots of good experiences, which will help create a new reference point in the brain,’ explains Stace. You want your brain to think ‘Oh actually, that was OK after all,’ so it can resist putting on its yellow hard hat the next time you perform that movement – or grab your running shoes. - Expect setbacks.
‘If, midway through your rehab or a comeback run, you do feel some pain don’t overreact to it or catastrophise. ‘Accept that you went beyond your current baseline on that occasion but focus on the fact that you have moved on from where you were,’ suggests Goom. - Be kind to yourself.
Look after your basic health needs while you are healing. ‘Good food, hydration, sleep, stress management and social contact,’ says Stace. ‘All of these will affect your ability to recover and heal.’ - Work with a sports medicine practitioner, such as a physio, to set realistic time-framed rehab goals. The study mentioned above found that a lack of goals in rehabilitation led to a less successful return to sport.
- Don’t be in denial.
Do not ignore physical symptoms, such as joints locking or giving way, swelling, bruising or sensations of heat, pins and needles or numbness. Get checked out.
Runner’s World, October 2018