No Pain, No Gain?

I copied this article to my blog because it raises some interesting points about pain. Not all are entirely agreeable to me, but it is thought provoking.

‘Pain is inevitable, but suffering is optional.’ So goes a well-known but anonymous quote. For many athletes, pain is a normal everyday experience and success is often achieved in spite of pain. But what’s the best strategy for coping with and overcoming pain and how can athletes distinguish between benign and potentially damaging pain? Matt Lancaster looks at the latest evidence

Pain is synonymous with sport. Endurance athletes relish the challenge of ‘pushing through pain’ while boxers expect to fight on regardless of a jarring blow to the chin. Adulation is reserved not just for the star rugby player, but anyone who can play through pain and contribute to the team. Winners and heroes overcome pain. Losers don’t.

But the price of pain can be high. Pain both demands attention and creates fear(1). It can restrict the ability to concentrate on performance and take away the opportunity to compete. Pain can even end sporting careers. The relationship between pain and sport is filled with challenges for sportsmen and women as well as those who support them. However, although pain of some description is no stranger to most athletes, it’s still a curious phenomenon in many ways. For example, consider the following questions:

* How are some people able to shrug off a painful injury?
* How can two athletes with the same injury experience different pain?
* Why do some pains seem to last ‘forever’?
* Why can some people compete, seemingly regardless of pain, while others struggle to overcome even a minor niggle?

This article will explore these questions, offering practical advice about when it is appropriate to perform in the presence of pain, when you should consult a professional, and how to best approach pain in a sporting environment.

The diagnostic dilemma

If you tear your hamstring muscle or sprain an ankle it hurts – obviously. Since the 17th century, the medical and scientific world has sought to diagnose pain by identifying the particular tissue that has been injured. For example, the philosopher René Descartes proposed that a pure pain sensation is transmitted from the damaged body to an entirely separate organ, the mind, just as… pulling on one end of a rope…makes to strike at the same instant a bell which hangs at the end(2,3). Descartes separated the body from the brain, and even today it is usual for people to make a distinction between physical pain and mental pain(3,4).This is especially the case in sport.

However, there are some problems with this classical view of diagnosis. For instance, an extensive network of nerves supplies the various tissues in your back, making them potential sources of pain when injured(5). It follows that if you can identify the damaged spinal tissue, for instance using magnetic resonance imaging (MRI), it should be possible to explain the pain.

The problem is that while MRI findings of severe damage to the discs or nerves is associated with the experience of pain, studies have failed to demonstrate a clear relationship between the majority of tissue damage observed on MRI and the patient’s pain(6). What’s more, almost 40% of people who have no history of back pain have abnormal, damaged spines at more than one spinal level when scanned using MRI(7)! Likewise, the damage shown by ultrasound investigations of athletes with painful patella tendons (jumper’s knee) does not necessarily correspond directly to the degree of pain experienced by the athlete(8).

This doesn’t mean that identifying the injured structure is not important or that it isn’t crucially involved in your pain. But looking to tissue damage alone (which is both frequent and often quite subtle in sporting injuries) to explain the relationship between pain and sporting performance is probably not sufficient.

A painful process

Another theory, first proposed in 1965, suggested that far from acting like an old-fashioned telephone exchange, your brain and spinal cord can actually increase or inhibit the transmission of pain signals(9). Gate control theory was revolutionary because it proposed a mechanism for the brain to have a modulating influence on the generation of all pains, and not just mental pain(10). While the original theory has been modified and expanded, it has essentially stood the test of time and been supported by 40 years of scientific research(11).

If you listen to the language people use to describe their pain, it soon becomes apparent that pain is quite simply pain, and is not separated into physical or mental compartments. All pain invokes not just a pure sensory response, but a range of thoughts and emotions also(3,12) and pain emerges from the integrated, combined action of the pain system(2,3). Simplistically, this system can be viewed as three separate parts of the nervous system, all of which modulate pain.

How do some people shrug off a painful injury?

Remember that following an acute injury, such as an ankle sprain, pain receptors are first stimulated by the mechanical stress and strain placed upon the tissue. ‘Inflammatory soup’ soon floods the tissue leading to peripheral sensitisation. Several hours later, similar chemicals will also lead to spinal modulation(19). Pain and sensitivity to movement and pressure increase over a period of a few hours; the time between the transition from the original mechanical pain (which may pass) to the maximum sensitised state may provide athletes with a ‘window of opportunity’ to shrug off their pain and continue competing.

However, this mechanism is probably only the tip of the iceberg. When you are totally focused on your opponent, or consumed by the contest, supraspinal and spinal modulation may act to inhibit the transmission or limit the awareness of the pain signal(18). We’ve all heard stories of sportsmen and women who have continued despite an injury which (theoretically) should have caused them to stop: a boxer with a broken hand, rugby players with torn ligaments, a long jumper with a strained hamstring etc. In the cut and thrust of competition, the pain system can ‘shut the gate’, and athletes are able to continue in spite of injured tissue(18). However, once your attention is drawn back to the acute pain (particularly following competition), awareness of the pain becomes strong again, especially if this also coincides with an increase in peripheral and spinal modulation.

So, should you ignore pain and try to shrug off an injury? Acute sensitisation is a normal, helpful process to encourage you to stop using the injured tissue and avoid further damage(20). It might be helpful to ask yourself the three questions in the box below.

There are a few other questions, which are perhaps even more important. We’ll get to these later. But remember, acute pain usually occurs for a good reason. It makes sense to seek professional advice as soon as you can. Sometimes people can overcome acute pain and continue to compete, but that doesn’t necessarily make it a wise decision!

How can two athletes with the same injury experience different pain?

Studies have confirmed that people respond differently to similar levels of painful stimulation(19). Differences exist not just in our individual sensitivity to a painful stimulus, but also in our perception of pain and how we display it. Pain is individual, even when the stimulus is not, but while we cannot know exactly what someone else is experiencing, our brains undergo quite similar activity when confronted with someone else’s pain(21). This is the basis for empathy and acknowledging someone’s pain is normal and important.

Our individual sensitivity to pain is in part explained by our genetic makeup (22-24), while studies involving twins have shown that learned behaviours are also important (25). Again, the division of pain into real and mental is unhelpful and the variation in pain between two athletes with the same injury lies at all levels of the pain system. Even for the same athlete, pain sensitivity varies under different circumstances, and perhaps not surprisingly, can become significantly less during competition(26).

It’s also worth noting that different groups in society may have significantly different pain responses, and this applies within sport. A study performed 40 years ago demonstrated that contact sport athletes could tolerate experimental acute pain for longer than non-contact athletes, while both groups could tolerate more acute pain than non-athletes(26).

Pain sensitivity may also be different in different people at different times; the way athletes display that they are in pain can vary, both between individuals and also between groups of athletes from different sports. It might be an extreme example, but imagine a footballer who could potentially be rewarded with a penalty responding to the pain from a kick in the shin. Now, assuming the tissue damage is equivalent, think about the same incident involving a Thai kick boxer who is in the middle of a title fight. Get the idea?!

Why do some pains seem to last forever?

During ongoing or chronic pain, adaptive changes at all levels of the pain system often outlast their usefulness in helping us protect injured tissues. Movements and pressures that would otherwise be normal continue to cause pain long after the risk of further injury has passed and often even once the tissue has essentially healed.

Examining possible tissue damage remains important when considering ongoing or recurrent pains, but a broader approach is required to address an athlete’s fear and anxiety about their ongoing pain and help them return to their sport. Focusing too much attention on pain can actually increase pain(18). It is probably more helpful to concentrate on working hard to strengthen the tissues at a sensible rate, regain normal fitness and aim to return to training.

Providing an appropriate environment for people to overcome ongoing pain is important and not always easy in sport. Coaches or team-mates who are angry at or ignore athletes with ongoing pain may contribute further to those athletes avoiding the very things that will help them return to full activity (such as a rehabilitation programme), and generate further anxiety that doesn’t help either(27). Getting this balance right and remaining positive is therefore important. People who develop an exaggerated, negative mindset towards their ongoing pain have been shown to experience both increased pain and emotional distress(28). Pain is a normal part of sport but the right mental approach can prevent it from becoming a catastrophe.

Does this mean it is OK to ignore ongoing pain? Well, it’s not quite that simple. Once again consider the three Cs. Any pain that has been present for more than a week or so, or keeps returning periodically is worth getting checked out by a professional who can not only assess for tissue damage but can also understand your pain and hopefully point you in the right direction before the maladaptive changes to your nervous system become entrenched.

Why are some people able to compete, seemingly regardless of pain, while others struggle to overcome even a minor niggle?

Although pain (especially acute pain) is related to tissue damage, this damage alone is not sufficient to explain pain fully. Pain is not just a sensation but results from the interaction between sensory inputs and brain processes, such as emotion and conscious thought. And pain is individual, not just to you as an athlete, but also to the time, circumstance and environment you find yourself in. Within the mechanics of the pain system, individual variation and modulation occur subconsciously, which helps to answer this question.

To ultimately address the relationship between pain and sport however, it is necessary to consider one further aspect of pain: your own ‘personal values’. We’ve already considered the three Cs as a guide to considering how to act in the presence of pain; however, as anyone involved with sport knows, making decisions about athletes in pain is often a judgement call. The three C questions only have meaning if we add a further, more personal line of questioning:

* Am I prepared to cope?
* How important is contributing a worthwhile performance to me?
* Am I prepared to suffer the consequences?

Having a pain killing injection two days before an Olympic final, regardless of the risks, would seem quite a reasonable thing to do for most elite athletes if it was the only way they were able to compete. Under similar circumstances, few casual joggers would agree to the same injection just days before a fun run. Entering a boxing ring, running 100 miles a week or crashing into a rugby scrum is not for everyone. Some people can continually and repeatedly overcome pain for the sake of their sport because they are prepared to. Sometimes they are rewarded with success, and sometimes, despite their desire to cope and contribute, their body succumbs to the consequences. Winners and heroes overcome pain sometimes. Losers often try and fail. Perhaps the most successful sports people are those who best understand the relationship between pain and performance: they are prepared to overcome pain, but make wise, informed decisions about when it is worthwhile trying to do so.

This post was copied from www.pponline.co.uk

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