Action for ME: The PACE trial and behavioural treatments for M.E. [position statement]

Thanks @adambeyoncelowe. I have now read your added clarification above. I have deleted my last sentence above too as not needed now.

I agree with you the phrase ‘careful training’ is open to misinterpretation. It would have helped if Van Ness in that letter had made clear, as he has elsewhere but not in the quoted letter that the training he uses with his patients only works on the anaerobic system (strengthening exercises etc) and that the aerobic pathway is dysfunctional and no amount of training can fix it. Afme have already used that quote out of context to suggest gradual training of all activity is possible with no mention Van Ness was only discussing training/strengthening the functional anaerobic pathway.

EDITED TO ADD

Sarah’s comment above citing a Davenport et al paper explains further that they hope by strengthening the anaerobic pathway they hope to mitigate some of the negative pem effects. However, I note Davenport et al (Van Ness’s name is on the paper too) does actually say increasing aerobic activity can begin once anaerobic training has been done. This contradicts where I have seen Van Ness say in a talk that no amount of gradual increase in aerobic training treats the dysfunctional aerobic pathway and that their focus is utilising the functioning anaerobic pathway to allow patients do do some short bursts of anaerobic strengthening exercises.

A FURTHER POINT TO ADD:

Also Van Ness in talks makes clear their anaerobic training exercises can only be done with mild and moderate people with ME. He says severely and very severely affected patients are too sick to do any anaerobic training with their team.

 

Ah, so he did say it (just not in the letter). I thought I'd seen this point debated before.

I agree it's all a bit muddled. It's made worse when some clinicians refer to 'aerobic threshold' when they mean 'anaerobic threshold'. Wasn't that in a video somewhere too?

 

Yes, I had to clarify my clarification LOL. Don't worry about it.

Quite. It's a bit of a mess. I suspect that some doctors just can't wrap their heads around the idea that exercise isn't a panacea, even in papers where they say that exercise is harmful!

It's like assuming that grains are needed for a healthy diet, so insisting coeliac patients must gradually reincorporate wheat, because otherwise they're not getting a balanced diet!

 

Thanks Sarah. I have not seen this before. As I just said in a response to Adam your comment above citing a Davenport paper explains further that they hope by strengthening the anaerobic pathway they hope to mitigate some of the negative pem effects. However, as you say I note Davenport et al (which includes VanNess as his name is on the paper)does actually say increasing aerobic activity can begin once anaerobic training has been done. This contradicts where I have seen Van Ness say in a talk that no amount of gradual increase in aerobic training treats the dysfunctional aerobic pathway and that their focus is utilising the functioning anaerobic pathway to allow patients do do some short bursts of anaerobic strengthening exercises.

My basic understanding of the aerobic and anaerobic pathways is both are always in use, just one predominates depending on which type of activity is used. Also the anaerobic pathway predominates always in the first two minutes of any activity then switches to using the aerobic pathway predominantly when the body can no longer sustain using the aerobic pathway predominantly then the body switches back for a final burst of predominant anaerobic activity. I am not an exercise physiotherapist so don’t take my explanation for gospel as I may have got some things wrong.

 

Ha, good analogy and agree!

 

I believe if people like Davenport and Van Ness talk about reaching the aerobic threshold this is when the pathway switches from predominantly anaerobic to aerobic. The official term is anaerobic threshold so yes confusing if they refer to it as the aerobic threshold. As our aerobic pathway is dysfunctional we want to stop or limit utilising the aerobic pathway depending on the level of aerobic dysfunction. Also those with ME reach the anaerobic threshold switching to aerobic quicker than many health people.

Also as I said above when our body reaches it limit of using the aerobic pathway and oxygen can no longer be utilised the body switches back to predominant anaerobic for the last burst of energy. I presume the aerobic pathway in people with ME is too dysfunctional for people to ever go through the cycle of predominant anaerobic ▶️ predominant aerobic ▶️ back to predominant anaerobic. Or if they do they will have severe pem, even long lasting damage in some cases. Caveat remains I am not an exercise physiotherapist so don’t take my explanation for gospel as I may have got some things wrong.

EDITED TO ADD

Sorry Adam in my brain fog I realise you didn’t say you didn’t understand the anaerobic and aerobic pathways, just that Van ness et al have been known to wrongly use the phrase aerobic threshold when the official term is anaerobic threshold.

FURTHER EDIT

Ah, shouldn’t be writing when brainfoggy and at my limit. I was wrong anaerobic threshold is when the body switches to predominantly using anerobic pathway. It still helps to remember the first two minutes or so of exercise uses predominantly anaerobic which may be a cause of the some of the confusion.

 

I am not an exercise physiotherapist so don’t take my explanation for gospel as I may have got some things wrong, but my basic understanding of the aerobic and anaerobic pathways is both are always in use, just one predominates depending on which type of activity is used. Also the anaerobic pathway predominates always in the first two minutes of any activity then switches to using the aerobic pathway predominantly when the body can no longer sustain using the aerobic pathway predominantly then the body switches back for a final burst of predominant anaerobic activity.

I believe when people like Davenport and Van Ness talk about reaching the anaerobic threshold this is when the pathway switches from predominantly anaerobic to aerobic (see edit below got this bit wrong). As our aerobic pathway is dysfunctional we want to stop or limit utilising the aerobic pathway depending on the level of aerobic dysfunction. Also those with ME reach the anaerobic threshold switching to aerobic quicker than many healthy people.

Also as I said above when our body reaches it limit of using the aerobic pathway and oxygen can no longer be utilised the body switches back to predominant anaerobic for the last burst of energy. I presume the aerobic pathway in people with ME is too dysfunctional for people to ever go through the cycle of predominant anaerobic ▶️ predominant aerobic ▶️ back to predominant anaerobic. Or if they do they will have severe pem, even long lasting damage in some cases. I think low blood volume also plays a role in the pem in people with ME. I haven’t a clue how it all links together.

*Edited to add

Ah, shouldn’t be writing when brainfoggy and at my limit. I was wrong anaerobic threshold is when the body switches to predominantly using anerobic pathway. It still helps to remember the first two minutes or so of exercise uses predominantly anaerobic which may be a cause of the some of the confusion.

 

I used to train using this principle, it is not sustainable, or wasn't for me. Before training I was mostly mild/moderate, since training I have remained moderate/severe. I more or less lost the ability to walk without it causing PEM and the actual distance I can now walk, regardless of accepting any consequences, is vastly reduced.

 

Thanks for sharing your experience Wonko. Van Ness et al have always said the severely affected are too sick for them to work with. Howver your experience indicates even the anaerobic training principle for people with mild to moderate pwme may not work and risk further deterioration. I am sorry it has reduced your functioning further.

 

It seems to work, for several months, which may explains why people are misled into thinking it works.

I got stronger, initially, I suspect primarily because my body learned to use the muscle it had more effectively.

But as soon as you need to build new muscle, which is inevitable if training anaerobically, things start to go wrong, although it took me quite a while to realise that.

After a while, as only lifting heavy enough things will keep you anaerobic, you'll eventually get "strong" enough so you can't jump straight to lifting them or damage will ensue. You have to warm up, which is aerobic, before doing the heavier anaerobic work.

There is no way around it, no matter where you start, how you train, how strong, or not, you get, it will happen at some point, at some point you will have to do aerobic warm ups to enable the anaerobic work to be "safe".

Staying below this level, below the level where you need to operate anaerobically, is aerobic. Staying above, you get stronger, so the level moves ever upwards.

The philosophy IMO is flawed.

(and there are also HR issues to be considered, keeping HR low seems to be a thing these days for people who don't like PEM)

 

If you look at my first post on this thread BACME actually also use it:

 

A lot of the confusion is because aerobic activities are ones that are done after you have reached the anaerobic threshold and are respiring anaerobically within the cell. So aerobics classes are ones where you exercise so hard you exceed the oxygen available and pass your AT. The damage caused by the products of anaerobic respiration tell the cells they need to increase the number of mitochondria which is what an increase of fitness is.

During the first few minutes of respiration, molecules are made which then feed into the kreb's cycle and start aerobic respiration going, this goes on in the background all the time.

I've watched a few videos of Mark Van Ness and it doesn't seem like he believes we all need to be doing more the way the BPSers think. He seems more concerned with helping patients do things they want to do so he is trying to find ways they can do them without causing themselves more injury.

I have managed to increase my fitness in tiny ways. Over months and months I have increased how many steps I can take so that I can get out my back door and lie in the sun. A small improvement can make an immense difference to the quality of life but it is something that should come from within not imposed and there is always a ceiling. Using a heart monitor has been of great help to me and I am very grateful for the Workwell information.

 

Sorry messed up the previous post, try again.

@Mithriel, you wrote, “A lot of the confusion is because aerobic activities are ones that are done after you have reached the anaerobic threshold and are respiring anaerobically within the cell. So aerobics classes are ones where you exercise so hard you exceed the oxygen available and pass your AT”.

I believe the bit in bold is worded slightly wrong. All activity begins using the anaerobic pathway predominantly for a couple of minutes then you switch to predominantly using the aerobic pathway which as you say utilises oxygen. The aerobic pathway is what is predominantly used during most of an aerobic class, going on a walk etc. During an aerobic class the body eventually hits the anaerobic threshold that switches back to using the anaerobic pathway predominantly - the feeling of hitting the wall. The body can only tolerate this for a short time due to the switch and build up of lactic acid etc. The more aerobic exercise you do the longer you will extend the time before hitting the anaerobic pathway again and thus increasing fitness. That is my basic understanding.

Van Ness’s work utilising heart rate training can help some who have mild to moderate severe ME. It’s harder to use when severely affected. I am bedridden and can’t use it much as I hit my AT so quickly. I would have liked to have tried it during the years I was moderate. Also Wonko’s experience indicates it may not even help all mild and moderate sufferers, although I know it helps some as you have shared it does with you. I think low blood volume also contributes to pem which is separate.

 

AEROBIC versus ANAEROBIC respiration.

This needs some clarification I think - I'll try! The first time I heard it said that our aerobic systems were broken, and that we needed to rely on our anaerobic respiratory pathways, I got confused, because in biology it is quite clear: humans cannot live without aerobic respiration.

Here's how I have reconciled my biological understanding re: aerobic versus anaerobic respiration.

Note: I was a biology teacher before ME stole my active life. I'll start with some definitions.

"Aerobic respiration" means using air, or more specifically oxygen, to respire glucose (and other food molecules) to provide energy.

"Respiration" is the metabolic process of extracting energy from food molecules. This happens in all cells of the body to provide energy.

"Anaerobic respiration" means the respiration of food molecules without oxygen. This involves alternative metabolic pathways to aerobic respiration and results in the build up of acids in the tissues. Anaerobic respiration provides only about one 16th of the energy per unit of glucose as aerobic respiration. It is thus very inefficient, and cannot be sustained for long. It is really an emergency means of providing energy, when oxygen cannot be delivered to the cells fast enough. (Note: I've highlighted the "an" in anaerobic respiration throughout this piece to help clarify which is which! For me, and my readers! LOL)

So here's the confusion. Higher life forms such as humans require aerobic respiration to survive! We cannot survive on anaerobic respiration alone: if we could we wouldn't need to breathe at all. So ME patients cannot have a totally defunct aerobic respiration system.

So, when Workwell say our aerobic systems are "broken", I think what they really mean is that, we cannot ramp up our aerobic systems like healthy people can.

I suspect some of the confusion comes from those "AEROBICS" classes that lots of us took in the eighties. The class I went to (back in the day) pushed us to "feel the burn", and to get out of breath. So technically, they were really "anaerobic" classes, because we were pushed to exercise at a level that we could only sustain for a short time - ie the exertion we attempted, tapped into anaerobic respiration. However attending these classes no doubt also helped us to improve the rate at which we could respire aerobically. In short we got fitter. So the classes improved our overall aerobic capacity - perhaps that's why they were called "aerobics" classes?

Note: Getting fitter, as I understand it, means a body can:
a) get oxygen to all the cells more efficiently (improved lung capacity, heart efficiency, and improve capacity of the blood/red blood cells to carry oxygen etc).
b) respire more effectively at cellular level (improved mitochondrial structure, number etc - meaning more enzymes to actually carry out the respiratory reactions that release energy).
c) remove lactic acid more efficiently (once oxygen is available) - thus allowing quicker recovery from those periods of anaerobic respiration.

Yet those "aerobics" classes cause confusion, because we now associate "aerobic respiration" with having to skip about in leotards and leg warmers! In fact, we are already respiring aerobically when we are at rest! (However, we are not pushing that aerobic level to one that increases our heart or breathing rate, which is what most people call "aerobic" exercise.)

So back to exercise and anaerobic respiration: When we (any person, not just ME peeps) want to do more, we need to ramp up our breathing and heart rates to ensure that oxygen reaches the muscles that require it. However, there is a time delay between starting to exert ourselves, and the required oxygen arriving at the muscle cells. During the lag time, the muscles will not have enough oxygen - so the cells respire anaerobically, while they await the arrival of the increased oxygen supply. Athletes "warm up" for this very reason - it means the supply of oxygen is already pumping to the muscles at the required rate, by the time they start their race or whatever.

So my interpretation, is that we - ME peeps - cannot ramp-up our aerobic pathways as normal folk can. (This could be at cellular level, or it could be at the level of heart, lungs and blood supply not supplying oxygen efficiently enough.) Thus, if we cannot ramp-up our aerobic pathways normally, then we are immediately compelled to use anaerobic respiratory pathways to supply the energy deficit. Anaerobic respiration is not very efficient, so not much energy can be produced this way. (And don't we know it!)

I assume that there must be some adaptation to anaerobic respiration that means that the more often it is used, the better it can function. However anaerobic respiration is not sustainable and this means that no matter how efficient it becomes, it is a short-term option only. As I understand it, using anaerobic pathways for as long as possible causes the build up of acids in the tissues, which will a) reduce the ability of the tissue to function in the moment, and b) over time cause harm. I think major caution is needed for ME folk with this, and this is why Workwell suggest very short periods of effort only.

Further, using anaerobic respiration creates an "oxygen debt". This means oxygen is required to remove the acids built up during the period of anaerobic respiration. Breathing and heart rate will remain high until those acids are cleared. I certainly note that my heart rate stays high for quite some time after exertion.

In truth I'm not wholly convinced that training our "anaerobic" pathways to be more efficient, will give us much extra functioning - at least not anything like normal functioning. Although perhaps, during recovery from these episodes (assuming the sessions are kept very short, as I have seen Workwell recommend) we will have some increased activity of heart and lungs, and perhaps that will help us to improve fitness a little?

I don't know. I'm certainly very cautious about any reference to the words "exercise" and "increase" - especially when they are used together!

****

Another note on exercise:

As I understand it, people who can get fit normally may go through two periods of anaerobic respiration during a period of exercise:

1. When they are warming up. Anaerobic respiration is required until heart rate and breathing rate catch up with the demand for oxygen. So this temporary anaerobic episode is quickly replaced by the ramped-up aerobic respiration. Fit individuals can then exert themselves for lengthy periods. Some anaerobic respiration may occasionally be used to top up the energy supply - eg when the runner goes up an incline, however, once the oxygen supply is ramped-up some more, the fit runner can continue aerobically for some time.

2. When they try to sustain exertion above their fitness level. At this point anaerobic respiration will kick in again because there is no more aerobic capacity to ramp-up. Soon, acids produced from the extra anaerobic respiration will accumulate. This cannot be sustained. Cramps, lethargy, etc result, and the individual slows down.

In my view people with ME never get that ramping-up of their aerobic capacity, so we go straight from one anaerobic scenario to the next with no sustained higher aerobic activity in between.

We do not have that wonderful aerobic capacity to just keep going. Marathon runners for example have very efficient aerobic capacities, and can keep on running. We don't. So we very quickly flag once we try to do anything. (I have a friend who recently did a 24hour race! Yup 24 hours running! I went to cheer her on at 23 hours into her race, and even though she had dropped to a walk for a short rest break, I still couldn't walk at her pace for even 20 metres!! Meh!).

Anyway, I think Workwell are right, we need to do things in short doses, with rest times in between to allow recovery. However I'm not so convinced that careful activity of this nature can "improve" us enough to aim to "increase" activities towards anything like normal functioning.

As may know, I monitor my heart rate and use it to judge what I do. If I rest after doing a "thing" and my HR doesn't drop as I expect it to, then that is my sign that I need to pull back. Heart rate remains high whilst there is an oxygen debt (pay back from anaerobic respiration) and so watching my HR can help me judge how well I am recovering from an activity episode.

Anyway - hope that isn't too rambley. I think there is much that we can do to help ourselves. BUT my view is still, that any activity management we engage in, is most useful when thought of as keeping within our "energy envelope", and not as a means to aiming to "increase" what we do.

"Increase" is only possible after healing, and as yet we don't know how to heal ME.

****

PS. "Respiration Rate" is the rate at which glucose molecules are being respired to produce energy in the cells. This can be roughly measured by measuring an individual's breathing rate. "Breathing rate" is often called "respiration rate" in medical circles. This leads to a confusion that the word "respiration" means the act of "breathing", but that is not technically correct. Breathing rate will, of course, often correlate with cell respiration rate, hence the reason it is used as a proxy measure.

PPS - This got longer than intended. I might turn it into a blog post.... so if you spot any typos, tell me now. Cheers!

PPPS -Edits to bold "an" in a few more "anaerobic" words;

 

LOL... I see I'm not the only one trying to describe all this. Just seen your posts @Mithriel and @anniekim - which means I've been writing quite some time... Hope my lengthy post doesn't further confuse. xx

 

Not at all @Keela Too, really helpful detailed explanation, thank you, and confirmed how I thought it works.

 

I over simplified deliberately lol (both to put it in terms that others would understand and because it was several years ago and I have forgotten most of what I used to think I knew).

Recall suggests there are at least 3 different energy mechanisms, one that lasts for no more than a couple of seconds but recharges rapidly (in a healthy person), one that last for 2-3 minutes and has about the same recharge time, and the one that's commonly described as aerobic.

Normally these are, as you say, used together, with different biases depending on the situation.

My point was, may be, that any activity that can be managed without physical stress is likely to be primarily aerobic, and remain so for as long as it can be done without stress, at which point the body has to call in additional energy systems to cope.

The point of training "anaerobically" is simply to bypass all of the aerobic activity required by "lesser" activities to stress the body enough so it jumps straight to having to recruit other energy systems. It doesn't mean that no aerobic activity is occurring, just that a lot less is (ETA - to get to that point).

Again, oversimplification, I did spend a couple of years studying this a decade or so ago, but I've forgotten most of it, and as I said before, it's flawed, it doesn't work, beyond 6-7 months anyway, so.......if I've got it wrong and that table is in fact a small peruvian dog, it doesn't matter.

 

We are still reading and digesting everything on this thread - many thanks for the feedback shared so far.

With regards to reviewing our material - patient involvement is crucial, and we will engage our existing Patient and Carer Reference Group who review all our new/revised resources. Many thanks to @NelliePledge for the link to @Keela Too's blog.

With regards to BACME - quoting from the BACME guide for clinicians doesn't mean we endorse it. We included this to highlight the sort of approach that patients can reasonably expect from a specialist clinic. Where we say that a baseline must be set before any appropriate increase in activity levels is attempted, we should have also added that, for some people, there is no appropriate increase. I will make sure this is amended.