I am very concerned that some ME/CFS clinicians, clinics and charities are recommending various versions of pacing up, and claiming it's NICE guidelines compliant because it's not GET and it is 'symptom contingent' therefore safe.
I was asked by someone who recommends pacing up to explain my opposition to pacing up and why I describe it as a version of GET. Here's a sllightly adapted version of what I replied. Apologies it's rather long.
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Pacing-up
The NICE guidelines describes GET as including fixed incremental increases in exertion and aimed at overcoming deconditioning and does not recommend it. However that does not mean that variations that use flexible incremental increases in activity can be recommended or are safe. My argument is that pacing up is equally unevidenced and carries a similar level of risk to GET, though the risk may become evident more slowly and is therefore less likely to be seen by therapists running short courses.
My take on pacing up is the idea is you find a stable baseline (if that is even possible) then when you are confident it's stable, you add a little extra activity in a symptom contingent way, and keep adding extra exertion gradually over weeks, to push gently at the envelope, and pull back if you get increased symptoms to stabilise again. To me that sounds like setting people up for push-crash cycles. I’ll try to explain why in the context of defining PEM and differentiating PEM from other forms of symptoms related to exertion.
I understand the rationale of pacing up proponents for trying to keep pushing at the envelope is to do with desensitising, as with people sensitive to light and sound. They may say something like: 'as you do a bit more you gradually become able to do more'. This has no basis in science or reality for pwME, either for exertion or sensory sensitivities. There is no evidence that pwME can build up tolerance to either by gradual exposure, and trying to do so can cause significant suffering.
And then of course there's the problem that many of us never have a stable baseline, nor do we have the practical support that would enable us to stay within some sort of baseline for longer than the few weeks of a course of therapy at an ME/CFS clinic when we may make extra support arrangements or take time off work in order to be able to participate. In real life events and work and caring responsibilities get in the way of stability. For many of us, it’s a case of do what you can, pace as best you can using whatever strategies work best for you, and take the consequences. In such situations, encouragement to think that gradually doing a bit more, even in a careful symptom contingent way, will lead to improvement is the opposite of what we need. Many of us need help to cut back, and permission and help to do so without feeling guilty or blaming ourselves for failing to sustain a baseline or to improve over the long term.
If therapists say they see patients improving while pacing up, what evidence is there that cause and effect is pacing up causing improvement? It could equally be an improvement for some unknown reason enabling pacing up. Are pwME cutting back on some other activity in order to be able to increase a specific activity? How long can they sustain this increase - how long do clinics follow them up? Can patients really recognize symptoms well enough to pace up. i.e. delayed effects and fluctuations can make it really difficult so even if it were safe and beneficial can it be safely operationalized (for many patients).
___________
I'm going to come to a more detailed look at pacing up by a roundabout route, starting with a close look at PEM, what it is, and what it is not, and how it affects pwME (people with ME/CFS).
Other forms of symptoms during or after exertion include:
I contend, as do many pwME and clinicians, that for ME/CFS to be diagnosed, the person must also experience PEM as defined below. This is my expanded version of a PEM definition, but I don’t think it differs from the NICE definition in any important way. I use the term exertion to include physical, cognitive, and social exertion.
PEM:
In addition to continuously present and/or fluctuating symptoms such as muscle pain, headaches, cognitive problems, orthostatic intolerance, rapid muscle and cognitive fatigability and many others, a specific phenomenon not seen in other conditions (probably) is post exertional malaise.
Specific characteristics of PEM:
Rather than thinking of PEM as a symptom, it may be better understood as a deterioration in ME/CFS severity level of unpredictable duration from a day, to days, weeks, months or permanent.
A key point I have learned from reading many people's experiences as well as my own experience is that it's often impossible to know which exertion or cumulative exertions we will get away with lightly, and which will be the trigger of a major long lasting episode of PEM which becomes long term deterioration.
This brings me to pacing up. Therapists assure patients that this is symptom contingent, but because PEM is delayed, and many of us can't tell until too late whether doing a bit more is taking us over the limit into triggering delayed PEM until it’s too late, that is encouraging risky behaviour. Why do so? Why encourage people to test their limits and risk more frequent PEM and possible long term deterioration?
Also real life for most people doesn't enable entirely consistent activity levels each day, nor does it allow us to live without our necessary activities inducing increased symptoms. In my case, for example, I experience rapid muscle fatigability accompanied by increasing muscle pain with every physical activity right from the start of that activity. So my symptom contingent pacing requires me to judge all the time whether the level of pain and weakness I'm experiencing is indicating I must stop now, or in 1 minute, or I can get away this time with a few more minutes exertion. It's also complicated by increasing nausea and OI if I push on. Heart rate monitoring helps me with this, but it's not an exact science. And if I stop and rest, how long should I rest before continuing or doing another activity? Again, it's guesswork based on 35 years experience. Diary keeping is of very limited use, as my capacity to exert without significant consequences varies from day to day unpredictably.
If PEM were simply the pain and exhaustion that builds up immediately during and after each individual activity (fatigability), it would be relatively easy to pace. We could simply decide on the balance between how much we want or need to continue the exertion and how difficult our symptoms are to endure, then rest until we feel ready to do the next activity. The problem with pacing is not these immediate symptom contingent decisions on when to stop and rest, but the cumulative effect of all those little decisions we make over the day, and subsequent days.
I can do pacing up, symptom contingent for a while, even for many weeks, then it unexpectedly catches up with me and I crash badly for days or weeks. After a while of living like that, we can end up much sicker than before, with a long term or permanent deterioration to much severer ME/CFS. This is effectively what has happened to me.
Some therapists claim they can advise people on how to do pacing up safely, but there is no research evidence to support this. I'm sure some of their patients will have told them it has helped them to do more, but unless very detailed objective data of their physical, cognitive and social exertion is collected over a period of months, or preferably years, alongside their changes in severity level and ability to function, how can the patient or therapist know whether they are really doing more overall, and whether the effect will last? And if improvement is clear, how can anyone know it wasn't that the ME/CFS improved for other unknown reasons, which then enabled that person to do more without detriment?
Why encourage patients to take the risk of long term deterioration by encouraging them to think pacing up can lead to improvement in overall health when there is no evidence to support this, and considerable anecdotal evidence that it can lead to harm? Surely therapists sign up to 'first do no harm'. It is also dishonest to tell patients that we can improve by gradually doing a bit more. This is a lie based on wishful thinking and unevidenced theorising about desensitisation.
The only safe advice on exertion management, in the absence of evidence for increasing activity, is staying within our energy envelope. If that envelope expands due to unknown good fortune, then of course people will naturally start doing a bit more. We need our therapists to be honest with us, and to provide information on different strategies to enable us to avoid PEM and worsening where possible, including wearables and apps, not to hold out false hope that pacing up will lead to improvement.
I was asked by someone who recommends pacing up to explain my opposition to pacing up and why I describe it as a version of GET. Here's a sllightly adapted version of what I replied. Apologies it's rather long.
____________________
Pacing-up
The NICE guidelines describes GET as including fixed incremental increases in exertion and aimed at overcoming deconditioning and does not recommend it. However that does not mean that variations that use flexible incremental increases in activity can be recommended or are safe. My argument is that pacing up is equally unevidenced and carries a similar level of risk to GET, though the risk may become evident more slowly and is therefore less likely to be seen by therapists running short courses.
My take on pacing up is the idea is you find a stable baseline (if that is even possible) then when you are confident it's stable, you add a little extra activity in a symptom contingent way, and keep adding extra exertion gradually over weeks, to push gently at the envelope, and pull back if you get increased symptoms to stabilise again. To me that sounds like setting people up for push-crash cycles. I’ll try to explain why in the context of defining PEM and differentiating PEM from other forms of symptoms related to exertion.
I understand the rationale of pacing up proponents for trying to keep pushing at the envelope is to do with desensitising, as with people sensitive to light and sound. They may say something like: 'as you do a bit more you gradually become able to do more'. This has no basis in science or reality for pwME, either for exertion or sensory sensitivities. There is no evidence that pwME can build up tolerance to either by gradual exposure, and trying to do so can cause significant suffering.
And then of course there's the problem that many of us never have a stable baseline, nor do we have the practical support that would enable us to stay within some sort of baseline for longer than the few weeks of a course of therapy at an ME/CFS clinic when we may make extra support arrangements or take time off work in order to be able to participate. In real life events and work and caring responsibilities get in the way of stability. For many of us, it’s a case of do what you can, pace as best you can using whatever strategies work best for you, and take the consequences. In such situations, encouragement to think that gradually doing a bit more, even in a careful symptom contingent way, will lead to improvement is the opposite of what we need. Many of us need help to cut back, and permission and help to do so without feeling guilty or blaming ourselves for failing to sustain a baseline or to improve over the long term.
If therapists say they see patients improving while pacing up, what evidence is there that cause and effect is pacing up causing improvement? It could equally be an improvement for some unknown reason enabling pacing up. Are pwME cutting back on some other activity in order to be able to increase a specific activity? How long can they sustain this increase - how long do clinics follow them up? Can patients really recognize symptoms well enough to pace up. i.e. delayed effects and fluctuations can make it really difficult so even if it were safe and beneficial can it be safely operationalized (for many patients).
___________
I'm going to come to a more detailed look at pacing up by a roundabout route, starting with a close look at PEM, what it is, and what it is not, and how it affects pwME (people with ME/CFS).
Other forms of symptoms during or after exertion include:
- fatigability - the increase in symptoms and reduction in ability to function that happens in ME/CFS all the time during and after every type of exertion, and is used as a guide for symptom contingent pacing. Fatigability is a key feature of ME/CFS, but should not be conflated with PEM.
- Exertion intolerance - inability to continue with a physical exertion (also experienced in some heart and lung conditions)
- DOMS - delayed onset muscle soreness - may be part of PEM, but not the same
- PEF - post exertional fatigue - may be part of PEM, not the same.
I contend, as do many pwME and clinicians, that for ME/CFS to be diagnosed, the person must also experience PEM as defined below. This is my expanded version of a PEM definition, but I don’t think it differs from the NICE definition in any important way. I use the term exertion to include physical, cognitive, and social exertion.
PEM:
In addition to continuously present and/or fluctuating symptoms such as muscle pain, headaches, cognitive problems, orthostatic intolerance, rapid muscle and cognitive fatigability and many others, a specific phenomenon not seen in other conditions (probably) is post exertional malaise.
Specific characteristics of PEM:
- Triggered by a small increase in exertion that pre-illness would not have caused problems - can be a single exertion, or cumulative effect of exertions over a day or more, sometimes building up over much longer
- Delayed onset of 12 hours to up to 3 days after the triggering exertions
- Duration of PEM usually significantly more than a day, often several days or weeks, sometimes leading to long term deterioration
- PEM symptoms include an increase in the regular daily ME/CFS symptoms plus additional symptoms that pwME doesn't have all the time.
- Significant further reduction in the already reduced capacity to function.
Rather than thinking of PEM as a symptom, it may be better understood as a deterioration in ME/CFS severity level of unpredictable duration from a day, to days, weeks, months or permanent.
A key point I have learned from reading many people's experiences as well as my own experience is that it's often impossible to know which exertion or cumulative exertions we will get away with lightly, and which will be the trigger of a major long lasting episode of PEM which becomes long term deterioration.
This brings me to pacing up. Therapists assure patients that this is symptom contingent, but because PEM is delayed, and many of us can't tell until too late whether doing a bit more is taking us over the limit into triggering delayed PEM until it’s too late, that is encouraging risky behaviour. Why do so? Why encourage people to test their limits and risk more frequent PEM and possible long term deterioration?
Also real life for most people doesn't enable entirely consistent activity levels each day, nor does it allow us to live without our necessary activities inducing increased symptoms. In my case, for example, I experience rapid muscle fatigability accompanied by increasing muscle pain with every physical activity right from the start of that activity. So my symptom contingent pacing requires me to judge all the time whether the level of pain and weakness I'm experiencing is indicating I must stop now, or in 1 minute, or I can get away this time with a few more minutes exertion. It's also complicated by increasing nausea and OI if I push on. Heart rate monitoring helps me with this, but it's not an exact science. And if I stop and rest, how long should I rest before continuing or doing another activity? Again, it's guesswork based on 35 years experience. Diary keeping is of very limited use, as my capacity to exert without significant consequences varies from day to day unpredictably.
If PEM were simply the pain and exhaustion that builds up immediately during and after each individual activity (fatigability), it would be relatively easy to pace. We could simply decide on the balance between how much we want or need to continue the exertion and how difficult our symptoms are to endure, then rest until we feel ready to do the next activity. The problem with pacing is not these immediate symptom contingent decisions on when to stop and rest, but the cumulative effect of all those little decisions we make over the day, and subsequent days.
I can do pacing up, symptom contingent for a while, even for many weeks, then it unexpectedly catches up with me and I crash badly for days or weeks. After a while of living like that, we can end up much sicker than before, with a long term or permanent deterioration to much severer ME/CFS. This is effectively what has happened to me.
Some therapists claim they can advise people on how to do pacing up safely, but there is no research evidence to support this. I'm sure some of their patients will have told them it has helped them to do more, but unless very detailed objective data of their physical, cognitive and social exertion is collected over a period of months, or preferably years, alongside their changes in severity level and ability to function, how can the patient or therapist know whether they are really doing more overall, and whether the effect will last? And if improvement is clear, how can anyone know it wasn't that the ME/CFS improved for other unknown reasons, which then enabled that person to do more without detriment?
Why encourage patients to take the risk of long term deterioration by encouraging them to think pacing up can lead to improvement in overall health when there is no evidence to support this, and considerable anecdotal evidence that it can lead to harm? Surely therapists sign up to 'first do no harm'. It is also dishonest to tell patients that we can improve by gradually doing a bit more. This is a lie based on wishful thinking and unevidenced theorising about desensitisation.
The only safe advice on exertion management, in the absence of evidence for increasing activity, is staying within our energy envelope. If that envelope expands due to unknown good fortune, then of course people will naturally start doing a bit more. We need our therapists to be honest with us, and to provide information on different strategies to enable us to avoid PEM and worsening where possible, including wearables and apps, not to hold out false hope that pacing up will lead to improvement.
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