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What is Post Exertional Malaise (P.E.M.)? #ME #PEM #MyalgicEncephalomyelitis

Posted in Personal Blog


I know I bang on about all things ME (Myalgic Encephalomyelitis) on a regular basis but amazingly it is still a very much misunderstood illness. I frequently come across people who have never heard of it or ~ even worse ~ have heard of it but have read the misinformation which has been printed in the tabloids, on television on the news or sitcoms purveying it as being the illness of the lazy, of the mind, easily cured once they are told to get off their butts and exercise and see a psychiatrist to sort their mind-set out! To say recent tabloid articles saying GET and CBT are the miracle cure of two thirds of ME sufferers has made me angry would be a massive understatement. It makes me feel like screaming and raging at those who are falsely giving hope to those who are really sick and vulnerable plus giving ammunition to those who like to falsely convey to all and sundry that it is a psychiatric illness. That can be overcome with the help of psychiatrists and physiotherapists who push gradual exercise and cognitive behaviour therapy on the unsuspecting patients.

Myself and my two of my three daughters have this blasted illness and we can tell you from personal experience, having undergone both GET and CBT, not only does it NOT make you better, it also makes you significantly worse than you were in the first place, so your quality of life has deteriorated and your ability to function at the level you were is taken away from you.

HOWEVER, I do believe that those who suffer from fatiguing illness such as post viral syndrome and other similar illnesses to that could benefit from both CBT and GET because these, although initially may seem similar to ME (otherwise known as the stupid name Chronic Fatigue Syndrome ~ CFS) are not because they don’t have the crucial post exertional malaise and cognitive dysregulation which causes havoc with the lives of ME sufferers.


So, for the uninitiated, I give you the definition of M.E. from Invest in ME Research;

ME ~ what it is…

  • Myalgic Enchepalomyelitis (M.E.) is a severe systemic acquired illness.
  • It is estimated to be 2 times as common as MS and 3 times more prevalent than HIV/AIDS
  • There are clear clinical symptoms which manifest predominantly based on neurological, immunological and endocrinological dysfunction.
  • Multi~factorial pathogenesis with the hypothesis of initiation by a viral infection prominent.
  • Most frequently follows an acute prodromal infection, varying from upper respiratory infections, bronchitis or sinusitis, or gastroenteritis, or an acute “flu~like” illness.
  • Before acquiring ME most patients were healthy, leading full and active lifestyles.
  • Reaction to physical and mental activity and sensory input is unique to ME.
  • Over~exertion can make ME worse and the effects are often delayed and may not be seen within 24 hours.
  • Symptoms can range from mild to very severe and can include; cardiac and cardiovascular problems, cognitive dysfunction, gastro-intestinal problems, headaches, hormonal imbalance, immunological problems, muscle weakness and intense pain, neurological problems, sleep problems

ME has been formally classified by the World Health Organisation as a neurological disorder in the International Classification of Diseases (ICD) since 1969 (ICD~8: Vol I: code 323, page 158; Vol II (Code Index) page 173).

So, as you can see by the definition, ME cannot be simply fixed by working out or increasing exercise and undergoing therapy with a psychiatrist ~ but oh how I wish it were that easy!

As you can also see, post exertional malaise is by far not the only symptom us ME sufferers have to tolerate, but for today I am going to focus on it as it may help friends and family of sufferers to realise that we don’t cancel plans or go home early through not wanting to socialise or do things with you ~ it’s quite simply that our bodies won’t let us, that we are beyond exhausted, in pain and can’t physically do it.


So ~ what is PEM (Post Exertional Malaise)? below are a few definitions I have found for you;

“The predominant symptom of ME/CFS is usually severe fatigue and malaise following mental or physical activity. The full extent of this exhaustion often becomes apparent only 24 to 48 hours after the activity (assuming, of course, the person was not already in a “recovery period” from a previous activity).” ME Association

“The most apparent features are extreme post~exertional muscle fatiguability, which is quite distinct from chronic “fatigue” or tiredness, together with recurrent nausea and profound incapacitating malaise. It is striking how consistent are the symptoms that characterize this condition. The exhaustion experienced by patients is extreme: “the disabling weakness and exhaustion a patient with ME / ICD~CFS experiences is so profound that “fatigue” is probably an insult.” Invest in ME Research

For me personally I find that emotional or mental stressors have double the impact on me than the physical exertion ~ which is still severe. The fatigue is like no other I have experienced, it is overwhelming and frightening, usually ~ again this is for me (all patients experience symptoms differently to varying degrees of impairment) it brings with it terrible cognitive payback, with what we call “brain fog” ~ although I will blog about that issue another time.

I wanted to find out if this terrible sensation of having no strength or resilience in your body was common to other illnesses or just ME ~ when I searched “Is it unique to ME” this article came up in my search

I’ll give you some snippets below but you can click on the link above to read the full article…

“Fatigue is a significant and disabling symptom in many illnesses, including multiple sclerosis (MS), Lupus and Rheumatoid Arthritis. Fatigue in Lupus has been described as “an extreme fatigue that interferes with many aspects of your daily life.” MS fatigue or “lassitude” is severe fatigue that is unrelated to physical activity, occurs on a daily basis, and interferes with functioning. Both of these descriptions are similar to how ME/CFS patients describe their fatigue, but is the effect of exercise on these illnesses that may truly distinguish them.”

Okay, so so far I find that fatigue in ME is similar in many respects to fatigue in MS, Lupus and Rheumatoid Arthritis ~ so what do they mean by “is the effect of exercise on these illnesses that may truly distinguish them” ~ so I read on…

“There is a growing body of research that MS patients can tolerate aerobic exercise, and also benefit from it.”…”The Medical Advisory Board to the National Multiple Sclerosis Society recommends regular aerobic exercise geared to the persons ability as one of the clinical management strategies for MS fatigue, even for the 50~60 percent of MS patients who say fatigue is one of their most troubling symptoms.”

I find that interesting ~ so unlike ME, for MS sufferers exercise can help them with their fatigue ~ I continued reading…

“The same holds true for patients with Lupus and Rheumatoid Arthritis. Aerobic exercise training in Lupus patients has been shown to improve aerobic capacity and exercise tolerance, while also not exacerbating the disease. In Rheumatoid Arthritis, studies show that regular exercise helps reduce joint pain, increase joint mobility and strength and improve mood. While all these illnesses require rest and pacing, exercise does not appear to have the same aggravating effect on symptoms that it does with ME/CFS.”

So basically ME seems to be unique with the symptoms of PEM, therefore gradual exercise therapies (GET),  which are thrown at patients not only don’t make them any better but instead can in many cases (like ours) make sufferers decidedly worse. For many patients being forced through this therapy means that once it is stopped they may never regain the level of function they had prior to starting GET, but if they do it is a very long and slow process. Simply put, exercise with ME aggravates and exacerbates the illness and does not benefit the sufferer in any way. However ~ I have to say that within the category of ME diagnosis you will find sufferers of varying severity and fluctuating symptoms ~ those mildly affected will be able to tolerate being more physically active than a moderately severe sufferer. A very severe suffer simply cannot get out of bed, let alone exercise.

So it would seem post exertion malaise and the exacerbation of symptoms due to exercise is unique to ME.  You can read the full PEM series from this article here.

So now you understand how exertion affects a person with ME you are probably wondering how we manage to get anything done at all?  Having been down the road of Gradual Exercise Therapy (GET) and Cognitive Behaviour Therapy (CBT) ~ I can tell you that these therapies simply don’t work YET they are still being touted by the media and many health care professionals (within the psychiatric community) that these work and can “cure” two thirds of ME sufferers! That makes my heart sink ~ life is already hard enough but to have this misinformation in the media is catastrophic in spreading true awareness about this illness. Jane Colby from The Young ME Sufferers Trust (TYMES Trust) recently appeared on the Victoria Derbyshire show to fight the corner of those who despair that this treatment is being touted as a cure as a result of the PACE trial (which purports GET and CBT as treatments to cure those with ME). The TYMES Trust recently posted this on their facebook page;


Let us establish at the start, that Tymes Trust does not endorse or support MEGA.

What disease does this study purport to study? Does it even study ME? The criteria are so wide, there will be various forms of fatiguing illnesses in this study which do not, in real life (epidemiology) exhibit the classic signs and symptoms of ME (Myalgic Encephalomyelitis). What will that tell researchers about ME? In our view, given the loose selection criteria, the term ME should have been omitted entirely from the study before asking the public – through a petition, of all things – to endorse it. Fatigue is not ME, and ME is not fatigue. This can be determined merely through reading Ramsay’s original ME definition and comparing it with the woolly MEGA criteria. What sort of science is it that does not remain true to the definition of the disease that describes so accurately how it affects patients?

Next, what about those we are asked to put our trust in to conduct this study? It has been observed by others that the list includes people who were involved with the PACE trial. The PACE investigators were responsible for a quarter of a million pounds of taxpayers’ money being spent to hide the data for five years from both patients and scientists. When, finally, an appeal tribunal Judge ruled against them, and ordered them to release the data, it was found on independent analysis that the claimed results had been wildly exaggerated. The resulting press coverage touting the bogus success of Cognitive Behaviour Therapy (CBT) and Graded Exercise Therapy (GET) for people with ME was therefore also wildly exaggerated.

Then there is the infamous CFS/ME NICE Guideline, recommending CBT and GET. One of those involved in producing the NICE recommendations, and now involved in MEGA, is attempting to subject children to GET, and to online CBT (which the protocol reveals leads to a form of GET) through the MAGENTA and FITNET trials. The potential damage to children with classic ME who might thereby undertake GET has horrified many parents and ME organisations alike, given the evidence that now exists for physical deterioration after exercise.

FITNET was recently covered by the media. The study on which it is based showed a nil result on follow-up. Yet we were led to believe that a two thirds cure rate could be hoped for from the new trial by this MEGA researcher. Our Executive Director, Jane Colby, explained our concerns on a current affairs programme, the BBC’s Victoria Derbyshire Show.

From The Victoria Derbyshire Show

Victoria: Jane, you don’t like this idea of CBT treatment. Why is that?

Jane: Well, I don’t think it’s as simple as that. I think it’s the fact that somebody has got a serious physical illness. We deal with children – and I’ve been there myself too as a result of a virus related to polio – who are completely bedridden and may be unable, hardly, to eat, or move, or have to be even tube-fed, seriously ill people – and if you give people like that some kind of CBT which encourages them to feel that their illness belief is wrong, which tends to happen with a number of people who deliver CBT, you encourage them to do too much. As a result of this, they will actually crash and they will actually get a lot worse.
We deal with children who are basically suffering from Myalgic Encephalomyelitis, and ME was originally defined as an illness where making a lot of effort, or even just a little bit of effort, would make you a lot worse. It also was defined as being very variable during the day, with an alarming tendency to become chronic. And all that has been backed up by the American Institute of Medicine recently. And I think people who have got these classic cases of very severe ME are different from people who have other types of fatiguing illness, and the chronic fatigue umbrella is pulling in people with this classic ME illness, which is NOT a mixture of illnesses. But Chronic Fatigue Syndrome IS a mixture of illnesses. The term is “heterogeneous”, and we know it’s heterogeneous, so you have to be very careful what you’re doing with your patient selection, otherwise you are going to give the wrong sort of treatment.

Jane was asked her views on the researcher’s promotion of this treatment UK-wide:

Jane: If these children and their parents are pretty much told that this is probably going to help, and then it doesn’t help, they’re very often not believed. Now what we see happening a lot, unfortunately, is that when this doesn’t improve the child’s condition, then the parents get accused of making the child ill, or the child is made to feel it’s their own fault and they’ve got some kind of psychiatric condition.

Victoria: You feel very passionately about that – the sort of not being believed about what’s causing it.

Jane: Well, the reason is that it leads to these erroneous false allegations of child abuse against the parents. We’ve seen 151 cases of this, and had to help them, and not one of them has been proved to be child abuse. Now this happens when some kind of psychological treatment is given and it doesn’t work. If it doesn’t work, then the parents and the child must be believed.

Jane was also asked for a comment on the BBC’s Today Programme:

Jane: I think if you use a psychological treatment to try to help people reduce anxiety and worry, that is one thing. If you try to use it to persuade people that they have a wrong belief when they say they are physically ill, you end up encouraging them to do enough to make themselves much worse, and there is plenty of evidence for that. And people are sick of experts who think they know better than they know their own children. They know what makes their children worse.

Apart from this misleading impression painted by some of the MEGA researchers that ME (which they persistently mix with chronic fatigue) can be cured by psychological means, it must also be remembered that the public’s opinion of people with ME has been tarnished by several of those involved in MEGA. This has been a smear campaign, spread by these researchers, and launched to the press through the medium of the UK CMRC Research Collaborative. The accusations against patients, since repudiated in the PACE tribunal appeal Judgement, were also spread directly to Parliament through the Collaborative. We refer you to our newly retitled Report, which is now on our website and contains a quote from the PACE tribunal appeal Judgement.

Shining A Light On The CMRC Setup (Minutes And Emails Obtained Under FOI)

This Report from Tymes Trust never ceases to shock. It is the shameful inside story of the UK CFS/ME Research Collaborative. Our Report is based, not on speculation or conjecture, but on direct evidence from emails exchanged by the participants. We think this is key reading for the ME community, now in particular because of the involvement of these people in MEGA.

In conclusion, we find it difficult to credit that any supposed “ME” organisation would be happy to work alongside these same researchers on anything, much less on a trial that does not even study ME per se and which will be the recipient of yet more millions of public money.


I am a huge supporter of Jane Colby and the TYMES Trust as they provided us with invaluable support and advice when the girls became sick, the support from the volunteers on the helpline who propped me up when I was emotionally fraught and terrified about how ill the GET was making my daughters. The emails I received direct from Jane herself offering me support, help and advice was incredible. The TYMES Trust helped me stand up to the therapists and question their methods and treatments ~ enabling me to be a stronger advocate for my girls and walk away from these treatments and prevent further damage being done. The work Jane does to promote awareness and understanding whilst providing support, knowledge and help for the many families who are desperate with the current situation and therapy choices is incredible. Especially as she is also a sufferer herself and gives so much of herself to help support the children and the families who need it.


table taken from:


Okay ~ so if GET and CBT don’t work then what can we do ~ what are our options? Quite simply ~ not a lot! Over the 6 (almost 7) years we have dealt with this illness we have really found only one method that works for us and that is what we call “pacing” ~ which is nothing to do with the PACE trial!

For us “pacing” means doing only what we can within our energy limits, to stop before we start to feel any fatigue from any activity ~ be it physical or mental. To take regular rests and to rest as and when our body dictate. This is to prevent any horrendous “crashes” which leave you bedridden and unable to function. “Pacing” varies for each individual as we all have different limits, different triggers and fluctuations. It means cancelling invitations/plans at the last minute and having to say “no” far more than saying “yes”. It can mean having to forgo a shower in order to have enough energy to prepare a meal. You become adept to using shortcuts to your personal hygiene on days when energy is particularly low ~ wet wipes instead of a shower, dry shampoo instead of a wet one, chewable toothbrush to save time over a sink brushing. Wearing head gear if the hair is completely unsolvable with use of dry shampoo. Wearing clothes suitable for wearing and sleeping in (jogging bottoms or leggings, loose tops or jumpers, pull on boots or flip flops). We know if we have a big event coming up to really rest up the preceding days in an effort to try and “store” some energy in reserve for the event, we also need to ensure that we have nothing planned for the next four or five days afterwards so that we can again rest to try and repair the damage caused by depleting the energy levels so severely in order to enjoy the one event we attended. It’s a case of I can do this if I don’t do that ~ having to cut things out in order to enjoy something else.

This juggling of how you spend your energy was often explained using the fabulous “spoon theory”, where you start the day with a set number of spoons, everything you do from waking takes away spoons and you have to decide how you spend them so you don’t run out. Sometimes you store extra spoons by not using them up on previous days ~ but it always comes with payback in the form of PEM if you do.

Now I find there is a better analogy available via this fabulous blog ~ which explains energy levels and expenditure in the form of a battery and it’s charging ability. In brief this is how it works, a person with ME has a dodgy battery compared to a healthy person.

Person with ME alongside a healthy person.


So when you set it to charge (when we rest and sleep) it never reaches full charge, usually a good rest or sleep will charge it to a maximum of 75%. Throughout the day your battery is drained bit by bit with every small thing you do, remember you start with a battery of 75% charge and “normal” people have 100% battery. During the day a person with ME finds that their battery drains much faster than their well counterpart, the same activity may cause a 10% battery drain on a ME sufferer but only 1% drain on a well person. This means you have to weigh up your options each and every day and prioritise what you want to do in order to not drain your battery fully before the end of the day. To help with this you can take intermittent rests to try and boost and recharge the battery a little in order to do this ~ but it means each and every day a ME sufferer has to compromise what they want to do with what they can realistically achieve. Sometimes, it is tempting to add a battery boost pack and do that extra something special that means a lot to you ~ but sadly this results in serious battery recharging issues, so the next day instead of having a 75% charged battery you find it’s only at 50% ~ keep pushing it and it will take longer and longer for the battery to charge.


Finally, in my search for information  I also found this…

“Post~exertional malaise (PEM), or post~exertional symptom exacerbation, describes a delayed and significant exacerbation of ME/CFS symptoms that always follows physical activity and often follows cognitive activity. PEM is a highly characteristic clinical and diagnostic feature of ME/CFS. In some respects, PEM is an illness within an illness…some studies indicate that the immune system and autonomic nervous system are involved in PEM”

Unfortunately this is true for me!





One Comment

  1. I feel like I wrote this. I have Hypothyroidism, Hashimoto’s and Adrenal Fatigue. People who don’t suffer from chronic illnesses that cause us to have rather debilitating brain fog, need to be made more aware. Thanks for taking the time to write this article.

    18th November 2016

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