About Pain

The Pain System #4 - Some more of the science



"Stress biology is concerned with the physiological mechanisms and behavioural strategies that enable organisms to survive or maintain homeostasis” “Pains prime adaptive purpose is to powerfully motivate the organism to alter behaviour in order to aid recovery and survive” 

(Gifford 1998)

This blog is an appendix to the previous three blogs on pain response and sensitisation. It is intended to give some more detailed background on how the brain in particular manages pain.

Part 1: How our Tissue Responds to Pain

Part 2: Amplifying Pain - Central Sensitisation

Pain 3: Shark Attack, It's all in the Mind

The basic function of pain is:

• To protect you.
• To alert you to danger - often before you are injured or badly hurt.
• To makes you move and think differently
• VITAL for healing

Pain is a normal response to what your brain judges to be a threatening situation.

The basic pain mechanism involves
Input / stimulus (the nerve endings in tissue) => process and evaluate (the spinal cord and brain) => output / response (the whole body). “We need a system that is able to monitor health of organisms own body and provide appropriate recovery response if damage occurs” (Gifford 1) Is Pain is all in your mind? Well, yes. The following areas of the brain are involved in evaluating pain inputs and formulating responses:

• area for organising and preparing movement.
• area for concentration and focus.
• area for problem solving and memory.
• fear, fear conditioning and addiction area.
• sensory discrimination area.
• area for stress response, autonomic regulation and motivation.
• movement and cognition area.

Following a potentially painful stimuli the evaluation and response also involves many different systems of the body:

1. The Sympathetic nervous system - this increases heart rate, mobilises energy stores ready for movement and releases adrenaline into the body.
2. The Motor (muscle) system is very important e.g. remove limb from flame, limp, run away, hide, prevent movement of area under threat. As we have seen, one problem is once trained the body tends to maintain these patterns after the stimulus has gone.
3. The Pain system itself - this lets you know what is going on i.e. you feel pain
4. The Endocrine system - Mobilises energy stores and suppresses any processes that are not vital to save energy (growth, repair processes, inhibition of inflammation, and inhibition of the immune system)
5. The Immune system - responds later and fights invaders, sensitises neurones, makes us sleepy to promote healing.
6. The Parasympathetic system - also responds later, it nourishes cells and heals tissue.

These systems are designed to work really hard for short periods in a threatening situation. They are the same systems that are activated when your body is under acute stress and are responsible to flight / fight responses. In the same way that prolonged stress which maintains long term activity in these systems is is undesirable, pain for a prolonged time causes sustained activity in these systems which causes over-sensitisation.

Persistent, chronic pain:

All pain is real but some pain persists after healing has occurred. This is termed persistent pain or chronic pain. In these situations the brain concludes that a threat remains and you still need protection. The brain can experience similar sensitisation to that described for the spinal chord in blog #2. The pain ignition nodes in the brain increase their sensitivity so less stimulus from the spinal cord activates them. They can even start firing with no stimulus from the spinal cord. The brain also creates more sensors in the pain ignition nodes and produces more chemicals to activate the sensors. This can be particularly powerful when it occurs in the part of the brain that deals with memory - you can relive the pain even though there is no danger to respond to. For example people with whiplash can feel pain when the car ahead stops even though they are not themselves stopping suddenly. The brain areas devoted to different body parts or functions start to overlap making you sensitised to pain in different areas of the body to where the stimulus originally occurred. This is conceptually similar to the chemical flooding of the dorsal horns in the spinal cord. The longer the pain persists the more advance these changes become. When the brain is sensitised it's not just pain that is persistently produced. Other protective systems also increase their sensitivity:

• The Sympathetic Nervous System makes you more aware and vigilant - as if you have turned a CCTV onto your body.
• The Endocrine system directs more energy to muscles for flight or fight.
• The Motor system keeps muscles constantly activated ready for fight or flight.

These systems then send signals to the brain in a self-perpetuating feedback loop. With a sensitive system inputs unrelated to tissue damage are judged as dangerous and can cause pain. You won’t know there is no damage or that its just your brain decided dangerous. It just hurts. Your thoughts are real. Real chemicals are released and real nerve impulses occur. Thought processes alone are powerful enough to maintain a pain state.


Altered muscle activity:

When you are in pain your brain alters your muscles activity. With pain being a warning sign for danger your body firstly increases activation of muscles to ready you to take action - flight or fight. This reaction is to aid protection of the whole body from further threat.

It also changes how your muscles work to help protect the local tissue where the pain is top prevent further damage. These changes cause bracing / splinting of the area by increasing the tension of muscles around the pain, and altering the movement of the whole area to reduce the load on the painful area (such as limping, or grasping the area). This works through taking load off the injured tissue by putting more load through surrounding tissue.

In the short-term these are all a positive strategy by your brain to protect your body. In the long term it becomes a hindrance not a help. 

Long term over-activation of these muscles makes them feel stiff and tight. This tightness can then change how you use other muscles. Smaller muscles who's role is to control and stabilise stop working as effectively as they perceive the larger muscles to be doing their job.

This altered muscle activity will then change how you move, feel and hold yourself.

So in rehabilitating any injury you need to address these changes in muscle activity. This is done with traditionally stretches and strengthening activities as well identifying and addressing threats and fears that are making your muscle system work so hard to protect you.


References

Gifford L, (1998) Topical Issues in Pain 1. Physiotherapy pain Association

Butler D.S, Moseley L.G (2013) Explain Pain, Noigroup Publications. 

Mense S, Gerwin R D, (2010) Muscle Pain - Understanding the mechanisms, Springer

Melzack R, Wal P.D (2008) The Challenge of Pain, Penguin Books.

Glutes - the new core?

I qualified as a physiotherapist in 1998 which seems a long time ago now. It was right on the cusp of a new era of physiotherapy treatment. During my training I spent a lot of time electrocuting people with various strange looking machines with the goal of curing all injuries and getting rid of all pain.

Whilst I was becoming a qualified practitioner learning my trade in the health service and studying for a Master’s degree these machines were being pushed aside in favour of the next trend - suddenly all ailments could be cured not by electricity but simply by ‘activating your core’.

A new muscle was introduced to our lexicon. The ‘transversus abdominus’ the magic cure all for back, knee and shoulder pain. Just get the patients to lie on their back and work this muscle in a very specific and magical way and all would become well with the world.

I set about my job of activating patient’s cores with great gusto, armed with my new argot - “zip and hollow”, “tuck in”, “gently pull your core into your spine”. It had to be just right or it wouldn’t work.

Once your patient's core was activated they were then shown how to challenge it using a very specific and precise series of exercises. We even had a gadget to measure whether the patient was perfectly working the core.

The result of all this precise deep abdominal activation was, well, not a lot.

I then started reading the research it was all based on - a few studies by some Australians - and realised that there were significant flaws in their arguments. Further reading found that there were many ways to work the muscles around the back and many of them far more enjoyable and effective than the strange ritualistic exercises we had been prescribing.

For me the final nail in the coffin came with a study published a few years ago showing that whilst exercise does help to reduce lower back pain no particular type of exercise is any better than any other (study).

What next? A period of sober self-reflection, perhaps challenging ourselves and our assumptions as medical practitioners?

Or instead, how about a new wonder muscle? The Glute.

Suddenly all my patients had weak, underactive, lazy glutes that just weren’t firing.

The cause for all these deactivated bums? Too much sitting. So you poor runners with your ITB, shin splints and achilles pain had all better get your glutes firing. Squeeze squeeze squeeze. You’d better clam and bridge for all you’re worth.

So everyone got better, right? Guess what?  Results were sketchy. Some patients recovered, others did hundreds of clams and bridges daily with no change to their symptoms.

So I shouldn’t bother with glutes exercises, or core, or Physiotherapists for that matter?

Well, not quite. All these muscles are important and may need looking after but they aren’t a cure for all pain and ailments.

The largest bum muscle, gluteus maximus, is a powerful muscle that helps power you forward when you run. The faster you run the harder the glute has to work. This is why sprinters tend towards a rather large behind.

The deeper gluteus muscles (medius and minimus) support and stabilise the pelvis as you run so when you land on one leg they provide the scaffolding to keep the leg steady to enable you to push off.  

So they are really important?

Yes…... but as part of a whole system. They work with other muscles, fascia, tendons, bones, joints, and nerves.  These other tissues and muscles all have their own part to play. Strengthening the glutes in isolation will rarely do very much.

In clinic I often see patients with ongoing issues after being treated by several other physios. They arrive confused and frustrated with their problems. Like many others they have been told that the cause of their problems is a weak core, glutes or both and have then engaged with their prescribed exercises for sometime with little benefit.

Case study 1

Sarah arrived in clinic with ongoing lower back and bum pain that was stopping her enjoying running. She had seen a physio previously who had declared that her glute wasn’t working. She had been given the standard bridges and clams and worked hard at getting her glute to work. But the pain continued and she still struggled to run. Her logic was that despite all the work she had done she still had a ‘weak’ glute. Her glute whilst lying on her side was very strong but in the one leg stand position which is key for running this strength didn’t translate into a strong stable leg.

She underwent a rehabilitation program focusing on balance and control on one leg, working all the muscles including the glutes in a running relevant position. She improved quickly and then slowly built up her pain free running over time.  

Case Study 2

Like Sarah, Mary came to see me after having seen several other physios. She had pain in her hamstring tendon which kept flaring up when she did a bit more running especially downhill running. She had been told she had poor biomechanics on the injured side and needed to strengthen her glutes to correct this.

On assessment the hamstring muscle on that side was much weaker, following a previous tear, thus when running downhill the weak hamstring caused more load on the hamstring tendon. For Mary treatment was based around hamstring strength work and advice on building her running up and discussing technique when descending.

Case Study 3

John came to see me after nearly two years of pain and frustration following an accident which injured his knee. He had been prescribed many exercises including some of the standing  exercises described below,  but he had still not fully recovered.

He had ongoing changes to strength, control and balance through his injured leg but he was also struggling with the changes the accident had had on his overall fitness and lifestyle.

For John the key to progress was developing a greater understanding of injuries, damage and pain pathways alongside guidance as to how to build his fitness and physical cofidence back up to the level he once enjoyed. This included glutes exercises to address the reduced strength and control on the right leg, but this was only a part of the overall treatment plan.

For more information on how pain works see these previous blogs. (here, here, and here)

So how do I address the glutes when assessing and treating in clinic?

• If I give a strength program to help reduce the risk of injury I will always include exercises to strengthen the glutes. Including some exercises that mimic how they will be used in the person's sport.
• With any lower limb injury I will always assess how the glutes are working and if I have any concerns I will include glute strength exercises in any rehab program. But rarely is it just the glutes I want to target.
• I will always tailor the glutes exercise I give to the specific needs, strength and ability of the patient.

So... what should you do?

I would recommend everybody to do some form of strength work as part of their training or even just as part of their life. Its pretty clear from research that all exercise is good for us and strength exercises are one part of this.

For people that do engage in sport evidence shows that strength work reduces injury risk and improves performance. For injuries evidence is also strong to show that exercises are one of the most useful tools we have to resolve the injury and reduce pain.

And when you engage in any strength program I would include some exercises to work the glutes.

So here are some different glutes exercises. I have split them into floor exercises and standing exercises that more closely mimic how we use the glutes when we run. I wouldn’t do all these exercises, just find two or  three exercises that you find challenging but not impossible. A combination of floor and standing exercises are good.

If you find 30 reps of an exercise is easy then you need to make it more challenging. I have suggested ways of doing this at the end of each exercise.

Floor Exercises

1) The Clam with variations. Find the one for you. You need to feel it working your glute and not cause any pain

Standard clam (feet together, lift the knee up an down) 

Standard clam with feet in air.

Reverse clam - (knees together, lift the top foot)

Reverse clam with feet and knees in air

To make harder add a resistance band around the knees for the standard clam and feet for reverse clam.

2) Side plank leg raises - a great exercise to work the ‘core’ and both glutes. These variations get progressively harder.

Side leg raise

Half side plank leg raise (on elbow)

Full side plank leg raise (on elbow)

Full side plank leg raise (on hand)

3) Front plank leg raise - extend hip by lifting foot up to ceiling (mainly works glute max as well as the ‘core’)

Standard leg raise

Elbow plank leg raise

Hand plank leg raise

Standing Exercises

1) Step up to balance

2) Side step up to balance

3) Single leg seated squat

4) Bulgarian split squat - drop hips down and bend knee (like your seating down)

Make these harder:

1. Higher step (exercises 1 & 2)
2. Lower seat (exercise 3)
3. Add weights (kettlebell, weight plate, dumbbell, bar, rucksack with bags of sugar in!)
4. Do the exercise very slowly and controlled (builds balance and control)
5. Do the pushing up phase of each exercise as fast as possible (builds power)

Sally's return to the roads - Sheffield Half 2017

I gave up road running 4 years ago after finally achieving my marathon sub 3 with 2:57 in the Amsterdam Marathon (at the 8th attempt!).

Road running for me had become a chore, a slave to the watch. Each session was spent chasing times, rather than enjoying what was after all a hobby. I was enjoying fell and trail running much more. The variety of terrain made each mile different so there was no point trying to work out paces, instead, it was more about running to feel and running each mile on merit. I was getting some good results from this approach, gaining selection for the Great Britain team for the Trail World Championships at ultra marathon distances for the last three years.

So, what made me suddenly come back to road running for this years Sheffield Half marathon? It was a local race but most importantly hilly!

The Sheffield Half Hill

The uphill first half, followed by 6 miles of fairly steep downhill appealed to the fell runner in me. I was a much stronger runner than when I was previously road running due to all the hill running as well as regular strength and conditioning work.

So, the experiment was, how much speed had I lost through fell running and could a half marathon be done on fell fitness? Instead of the speed intervals and tempo runs I was going to stick to what I enjoyed, shorter fell races for speed work and a hilly Dark Peak road run of 10 miles or so on a Wednesday night.

My half marathon build up included:

• Weekly mileage (20 weeks) of 55-76 miles.
• 7 Fell races, varying from 6 - 21 miles, the last of which was Edale Skyline (21miles) 2 weeks prior to the half.
• Howarth Hobble ultra marathon (33miles), 5 weeks before, also the GB selection race.
• 1 Parkrun, 6 weeks before.

The Parkrun was the first time in 4 years I had run fast and consistent miles. It was a PB at 19:04! The mile splits were 6:00, 6:08, 6:04. I wouldn't have thought I could do 1 mile at that pace, never mind 3 in a row!

Come half marathon day, I had no idea how I was going to do. I didn't work out any splits, targets or paces, instead I planned to ignore the watch and run to feel. After all, this is how I'd been running all my fell races. On the climb up to the Norfolk Arms, around 5 miles in I over took 2nd lady and from then onwards I held onto 2nd place. I had to work incredibly hard towards the end, I was feeling the lungs more than the legs by the 11-12th mile but was aware 3rd lady was right behind. The last mile was done in 6:01min/mile despite a slight uphill, and I only finished 10 seconds ahead of her in the end! My overall average pace was 6:27min/mile, giving me a time of 1:24:47. This was 2 minutes slower than my PB but that was set on a pancake flat course at the North Lincolnshire Half, 4 years ago.

So what did I learn:

• Speed and interval training is not needed for me to race a fast half marathon. When chasing road times I felt I picked up niggles from the high intensity sessions on hard surfaces. To perform at half and marathon distances the risk of these sessions (greater loading on tissue) may not make up for the reward (faster top end speed). 
• Consistent miles over months and years is the key to progress. The majority of these miles need to be done at an easy pace, but this race showed me that these base miles don't have to be race specific. Hilly off road routes which involve walking can be a valid method of getting these base miles in and are kinder to your body than high road mileage.  
• Adding strength and conditioning to my training seems to have helped me both maintain (or even improve) my road speed and reduce the number of 'niggles' I experience. This is in line with current research findings. 
• You can take the stress away from road running by ignoring the watch and running to feel. And it can be just as successful!

Howarth Hobble 2017 - I finished 2nd lady securing selection for GB. 

Ankle Strengthening

“Wibble wobble

Wibble wobble

Jelly on a plate”

(unaccredited)

Sprained ankles lurk around every corner, particularly for fell runners and orienteers who are maladapted to pavements and other flat surfaces. Other potential victims include beginners and road specialists heading out to the countryside for some spring air. And of course if you’ve sprained an ankle before then you likely to be more vulnerable.

Thankfully ankles are an area where the research is clear, albeit from other sports - ankle exercises reduce the incidence of sprains and re-injury.

Start by emulating a flamingo and stand on one leg.

Technique

Technique is important. Keep you foot and leg relaxed but stable, not rigid and fixed. Try to feel strong through the core and glute. Hold onto something to stabilise if you need to.

As confidence grows start moving your arms and your other leg - anything that throws you off balance.

Increase the difficulty by finding an unstable surface, using a wobble cushion or even a pillow, bed or sofa.

Other options include jumps and hops where you land on one leg and stabilise, and standing on tip toes on one leg which builds control when your on your fore-foot/mid-foot.

Technique, again

The options are endless. What is important is how you do the exercises. You need to be relaxed, stable and strong - not just wobbling all over the place.

Example program

Here are a set of exercises, to build your own program. Choose two from the static set and one from the dynamic set.

Try to practice them two to three times a week.

Your chosen exercise should be ‘just’ manageable with a focus on good technique. If it is too easy  you won’t be challenging and improving your balance. If it is too hard you won’t be able to master it.

If you find an exercise too hard start by holding onto something and progress by reducing the amount of support you use.

The static set

Choose two. Spend two minutes working on each one in sets of five to six repetitions with a short break between.

Standing 1 leg:

Star taps:

Run on one leg:

One leg stand to calf raise:

One leg stand wobble cushion:

One leg stand rotation (very challenging!):

The dynamic set

Choose one. Do up to ten repetitions and repeat three times.

Lateral hops:

Hops to wobble cushion:

Back lunge to hop forward:

Photos and videos taken in Fairplay Sport Personal Training studio, below our practice:

Why not practice with friends?