Open (Palmerston North, New Zealand) Effects of exercise at anaerobic threshold on post exertional malaise in individuals with ME/CFS

https://anzmes.org.nz/looking-for-p...xertional-malaise-in-individuals-with-me-cfs/
https://twitter.com/user/status/1076542568358387713

 

This seems to me like they believe the only reason we can’t exercise is because we’re doing it wrong....

 

The obsession with exercise for pwME is beyond irritating. I think we can figure out how much we can or can't do on our own?

 

No no - we can’t be trusted to do that. Don’t you know we have no idea how to manage our lives at all....

 

Can we please move this to "most irritating things people say" thread?

 

This is what UpToDate was saying before Nov 2018. That although aerobic exercise could be harmful for some, ME/CFS patients may be able to do graded exercise so long as they keep their heartrate low under the supervision of a physical therapist.

 

I don't understand why they would want people to exercise to anaerobic threshold. I am healthy and I like exercise because it lifts my spirits but no way do I go to anaerobic threshold these days. I tried the gym a couple of years ago and it was horrible. I probably do get to anaerobic threshold when I ski hard in deep snow but that is only because I like skiing in deep snow and I only feel terrible for about ten minutes.

 

Red flags. I hope they don't find participants.

Also, they can't even spell the name of their institution. Massey University.

 

It depends on details we don't have. This could be a good study. It could also be terrible. I would need to know more to decide.

 

from the first paragraph: "However, in stark contrast to healthy individuals, exercise exaggerates negative symptoms in those with CFS/ME."

the wording - to 'exaggerate' is to overstate, or stretch the truth. perhaps 'exacerbates symptoms' or 'aggravates symptoms' would be a little less offensive, given the historical context of 'hysteria' etc.

and yeah, not enough details.

 

The devil will be in the detail, for example it's not really clear what a “graded exercise test” is. Do they mean a gradually increased intensity during a CPET, or a programme of GET followed by a CPET?

However, at face value this does sound to be in line with the ideas of the Workwell people. That is, the real problems with 'exercise' for PwME start when we go over our anaerobic threshold - which may be very low in an ME patient - but that many patients can do some 'exercise' if they stay below that threshold. Note that 'exercise' for Workwell means something like 2 minutes of below-anaerobic-threshold activity followed by 6 minutes of rest, not 'exercise' as it's generally understood.

Some obvious limitations:
Excludes severe patients who exceed their anaerobic threshold simply by siting up or even just existing. No mention how they intend to control for other, non-physical causes of PEM that patients may encounter around the testing period, e.g. the cognitive effort of navigating to the testing location. Plus 20 participants isn't very many. No mention of a control group but possibly patients are supposed to be their own controls here, comparing exercising to threshold and exercising below threshold in the same person.

Assuming they're on the same wavelength as Workwell - trying to confirm, or otherwise, that careful anaerobic exercise is safe for milder ME patients - there are a few questions they could usefully look at.

Most of us don't have access to getting our aerobic threshold measured and use a heart rate formula instead to estimate it (50-60% of 220 less age). Is this formula reasonably accurate?

If there's a subgroup of patients with POTS as a comorbidity, how does that affect the above estimate?

They need to be clearer as to what they mean with 'exercise'. I agree with other members here that we don't need any actual exercise programmes; even at a level that's safe for an individual patient it would only displace other activities. If they mean what increase in heart rate is safe for activities of daily living, that would be helpful to know for those of us who use heart rate monitors for pacing.

In addition to 'safe intensity' they also need to look at safe duration of anaerobic 'exercise'. I can walk a total of 30 mins/day – but only if I split it into many shorter bursts spaced through the day. Walking 30mins in one go would lead to major PEM even if I stayed under my estimated anaerobic threshold throughout.

 

Plus - it seems to me there’s an assumption that it’s just exercise that’s the problem. Which I guess is not so surprising given that the researchers are exercise physiologists. But for me, cognitive load is a major factor as is sensory load.
Even if I could safely ‘exercise’, I don’t think my actual functional ability would be changed much if at all. I’m exhausted just going out in a car for instance.

 

I have to agree. Somehow this study makes me suspicious.

This doesn't sound like a cardiopulmonary test at first glance. It leaves me confused. Or they use strange language. During a cardiopulmonary test, you usually increase resistance incrementally until exhaustion (so it goes beyond anaerobic threshold). I remember the Workwell foundation worked with this kind of test?
What they write sounds like "exercise at the anaerobic threshold", where

So do they measure exercise on several days, weeks etc., where resistance is slowly increased from exercise session to exercise session...or do they simply do a CPET? If it's the first case, I'd say that's highly dangerous for pwME and I hope they'll find no participants, if it's the 2nd option, why only a 1 day CPET?

Ahhh, they do a CPET, but everytime they increase resistance they ask after fatigue. So, they want that pwME do exercise, but they acknowledge (or don't...) that exercise worsens ME, and so they're trying to find a "safe" threshold in pwME (using a small sample; and although this is highly individual). So, they want to show that pwME can do exercise if they remain at their "safe" threshold...leading to maybe claiming that exercise at this "safe" threshold will improve ME/CFS, i.e. then GET can be "safely" applied:

Using CFS/ME always suggests a BPS view to me I have to admit...

 

I think the difference is that the CPET studies fro the US use anaerobic threshold as an objective physiological state that allows a test of a specific physiological capacity - hoping to provide an objective biomarker. Exercise to anaerobic threshold is a necessary evil in this context - to get a physiological measure.

My impression is that in the study of the thread the investigators have decided to use anaerobic threshold simply because other people have and have not thought through what the purpose would be. The purpose of this study seems to be to correlate measures of activity such as heart rate with PEM. I don't see why anaerobic threshold is relevant at all there. Presumably PWME get PEM well below anaerobic threshold because going to anaerobic threshold is not something anyone does unless they are training in a gym, but PWME get PEM during daily tasks.

I think this is exercise physiologists turning the exercise physiology handle. I still see no reason why anyone should want to see how hard PWME can exercise - other than in the specific situation of Keller et al who were trying to find a biomarker. Exercising is not a rational therapeutic approach to an illness where exercise is unpleasant.

 

Does it seem, then, that there's a pointless risk to patients in this study? Should we be writing to tell the researchers and to ask them to change what they're doing?

 

I think there is a strong argument for that. It may be that they will increase activity gradually and never reach anaerobic threshold because people get PME earlier but the very idea of thinking of going up to anaerobic threshold as part of a treatment tailoring programme seems to me illogical and probably unethical.

 

Is anyone here able to take this on? It's beyond my competence!