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New Zealand Video: Exercise and ME/CFS, 2020, Lyn Hodges

Discussion in 'BioMedical ME/CFS News' started by Ravn, Oct 13, 2020.

  1. Ravn

    Ravn Senior Member (Voting Rights)

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    Thread split from
    News from New Zealand and the Pacific Islands
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    The talk is now available on Youtube (haven't watched it yet).
     
    Last edited by a moderator: Oct 14, 2020
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  2. Ebb Tide

    Ebb Tide Senior Member (Voting Rights)

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    Have watched the talk but not the questions yet. Well worth watching
    Need to watch again and take notes.

    Although small cohorts this looks really important work. She discusses and is critical from her findings of NICE guidelines for exercise, GET in PACE.

    Was contacted by the Polish researcher(sorry missed name) who has been working with Julia Newton. She was involved with them on reviewing and evaluating non-completers versus completers from a previous exercise trial of theirs- I think paper to follow.

    Also talks about the importance of investigating drop-outs in trial because they may not be able to tolerate the intervention.

    Talk last about 55mins, technical problems 13.21, restarts 17.40 so fast forward. About 15 mins questions after.
     
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  3. Subtropical Island

    Subtropical Island Senior Member (Voting Rights)

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    Thanks for posting @Ravn, just what I missed!

    Am at 8 min and not sure if I can keep watching it. (Thus no ‘like’ for the post as I can’t recommend the video). Will maybe try again later if no one else summarises for us.

    (ETA: cross posted with above - yay! Someone has! ....wow, took me 9minutes to write the above post ...sobering)
     
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  4. Ebb Tide

    Ebb Tide Senior Member (Voting Rights)

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    I did find the beginning quite hard going when she is talking about general exercise principles from her standpoint as an exercise physiologist, and nearly gave up, as I wasn't sure where it was going.

    But was glad I stuck with it. She digs in further to repeat CPET.

    Might be better to dive straight in at 10.42 where where she starts talking about her research.
     
  5. cfsandmore

    cfsandmore Established Member (Voting Rights)

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    1:04:50 Please listen to the guy who thought he didn't have MECFS anymore.
     
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  6. strategist

    strategist Senior Member (Voting Rights)

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    I've suspected that people can get used to living with it and maybe if they're mild and can find a lifestyle that is compatible with the illness they even begin thinking of themselves as not sick anymore.

    Which opens up the interesting perspective that maybe ME/CFS is a infection-triggered severe exacerbation of an already existing problem.
     
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  7. Subtropical Island

    Subtropical Island Senior Member (Voting Rights)

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    Just my casual (while listening) questions:
    Peripheral resistance (what causes it? - greater in ME/CFS cohort)
    (Later: oxidative stress?)

    72hr retest shows improved power output (whereas 24hr & 48hr show reduced) ...but the starting, baseline test, also started lower for the 72hr group? If so, does this mean anything about selection?
    (really good observation if it’s repeatable, and fits with my own n=1, so I’m looking for flaws before I get excited).

    had to stop at 28min, will be back.

    Good stuff! Glad to have recommendation to start at 10min and jump ahead when it hits technical hitch. Thanks!
     
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  8. Ravn

    Ravn Senior Member (Voting Rights)

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    Contains some interesting tidbits including unpublished (I think) data from upcoming publications. Also a finding I hadn't heard of before that a subgroup developed very high BP during exercise. Also bits I didn't understand about arterial(?) resistance. And a planned cooperation with Prof Tate's team on oxidative stress and exercise (not sure if this one's funded yet though).

    But I found the talk difficult to follow, largely thanks to my leaky memory. At the start there was a lot of switching back and forth between talking about exercise in general and exercise in ME. Later there was talk about the differences between two subgroups just named group 1 and group 2 and of course very soon I couldn't remember what the defining feature/s of the 2 groups were. Not helped by a graph-labelling mistake and having to grit my teeth at each mention of 'chronic fatigue'. Still, worth a watch. In fact, I may watch parts of it again myself.

    @Snow Leopard, if you can spare the time I would be very interested in hearing your take on this.
     
  9. Daisybell

    Daisybell Moderator Staff Member

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    I took part in a research study for her a little while ago. 72 hours between tests - and I was better on test 2. Also my arterial resistance was apparently excellent.... I think my arteries were less stiff than expected for my age.
    I was, I have to say, disappointed (that’s the polite version) as I had hoped to have an objective measure of my fatiguability, and I just measured as unfit.....
    I definitely get PEM, but the testing didn’t show it up.
     
  10. Snow Leopard

    Snow Leopard Senior Member (Voting Rights)

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    I'm still working on watching the video, but so far:

    The focus has been on maximal oxygen consumption and peak power output, but I don't believe that patients, or even some controls for that matter reached a true peak on the test - peak heart-rates are well below age norms and peak heart rate of deconditioned individuals can often be higher than a trained individual (as paradoxical as that sounds - my peak heart rate was a touch over 200 BPM, whereas the age predicted mean is around 190 BPM). Hence I don't really believe that the "increase" in peak workrate at 72 hours is meaningful, beyond participants becoming more used to the test.

    The reason why most ME/CFS participants are not reaching a true VO2Max (or a genuine peak heart rate) is because it is FUCKING HARD to achieve and most people stop, given the intense level of effort required. Participants who felt they didn't really work really hard almost certainly did not reach a true peak. All the discussion about RER is not relevant because VO2Max and peak workrate can occur well beyond reaching RER>1, especially in ME/CFS patients where there may be early metabolic limitations. The key point is that despite some motor units will be primarily utilising anerobic metabolism, but oxygen consumption can further increase by recruiting more motor units until the true cardiac limits are reached.

    Having said that, my alternative take on the 2 day CPET test doesn't actually require a true VO2Max and the level of exertion in Hodges study would be sufficient.

    I strongly agree with the recommendation that patients need to wait 3-4 days between exertion and I know that we can maintain fitness by exercising as little as once a week - but it does require getting the heart-rate right up there for a very brief interval of time (80% of predicted age maximum), which many patients can't achieve without significant symptoms.

    As far as high arterial resistance (high blood pressure during a CPET) goes, this is an expected autonomic response during a CPET. Trained athletes also experience high blood pressure at VO2Max. The purpose of this is to constrict the blood vessels, so that the additional blood is directed towards the activated muscles and the brain, rather than the unused muscles where the extra blood flow would be wasted. The pulse wave velocity finding may me explained by reduced parasympathetic/sympathetic balance in patients compared to controls.

    The blood flow in the muscles capillaries themselves is not regulated using the same mechanism as the larger arteries and veins. Instead, pressure in the capillaries is dynamic and locally regulated, the goal to maintain flow. However it is possible that this local regulation is not working effectively and this is one of my hypotheses to explain the results (it's possible Hodges will mention this later in the talk).
     
    Last edited: Oct 14, 2020
  11. Snow Leopard

    Snow Leopard Senior Member (Voting Rights)

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    38:00

    Hodges: No guidelines should be based on this research (referring to exercise guidelines based on the PACE Trial)

    She also mentioned she does not agree with the (UK) NICE guidelines.

    For reference, Group 1 is those who "could not keep heart rate below 70% of maximum heartrate" and Group 2, those who could. Group 2 only had 4 participants, 7 in group 1.

    She mentions that NICE guidelines claim that patients should be able to exercise between 50-70% of MHR (for 5 minutes).

    The mislabeled graphs was the Newton/Euromene study of "supervised" exercise.
     
    Last edited: Oct 14, 2020
  12. Hutan

    Hutan Moderator Staff Member

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  13. Trish

    Trish Moderator Staff Member

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    One thing that struck me about this was that she really needs a decent level of funding to do larger studies. She mentioned getting $2000 from an area health authority I think. When I think of the millions wasted by the likes of Chalder and Crawley and the PACE leaders in the UK by people who know nothing about exercise physiology I could weep.

    I wonder about some sort of concerted effort by patient groups to get together a funding bid for these sorts of studies internationally, with this researcher and the Workwell team involved.
     
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  14. Hutan

    Hutan Moderator Staff Member

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    I'm not sure about the idea that it's really important to do a CPET to identify your anaerobic threshold, so that you know how hard to exercise. Or the idea that there is a group of people whose BP goes up a lot during exercise and a group that doesn't have this happen.

    The problem with both ideas is that physiology does not seem to be constant in people with ME/CFS. Workwell's fundamental idea is that exercise capacity changes with exposure to exercise.

    Personally, I know that on some days, just washing the dishes for a bit can make my systolic blood pressure go over 150/160 bpm. But, on other days things are perfectly fine.

    I think Dr Hodges was saying that she could test people and tell them what group they are in and advise them how to exercise. I don't think there's enough evidence for that. I'm pretty sure that the same person, tested on another day, could have quite a different result.
     
  15. Trish

    Trish Moderator Staff Member

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    Good points, @Hutan, which is why I think researchers like Dr Hodges need to work with others like the Workwell people in a really big study that irons out these questions with much larger samples, and with related studies like using wearable technology that tracks individuals over time.

    If things like heart rate, physical activity, heart rate variability, blood pressure, blood oxygen, blood lactate etc could all be tracked simultaneously over days or weeks, alongside symptom and activity diaries that include cognitive activity etc as well, a much clearer picture could emerge.
     
  16. Dolphin

    Dolphin Senior Member (Voting Rights)

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    I think the vast majority of grants given out by national funding agencies go to researchers within the country. With the EU, it would be within the region. Exceptions can be made if there are particular resources available in particular countries e.g. the UK ME biobank got US grants. I’m not sure if that would apply in a case like this so you’d be more likely to need privately raised money ...
     
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  17. Ravn

    Ravn Senior Member (Voting Rights)

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    Yeah, I think there could be a lot of merit in the different groups working much more tightly together.

    Would be great if they could coordinate in such a way that everyone uses identical selection criteria and identical CPET protocols & other measures (the technical bits of how exactly to take and record the various measurements). Even better if they could also coordinate their trial protocols as much as possible so for example they all use MS patients as an additional control group, or they all test 24h vs 48h, or they all test before and after a specific intervention. In effect running the same trial simultaneously in several locations. Some potential benefits:
    • Clearer thinking, better protocols - due to having to discuss everything with a wider group of researchers bringing a wider range of views. I also suggest they employ @Snow Leopard as a special consultant ;)
    • Instant replication - if 3 teams on 3 continents come up with the same result it's more likely to be solid; if they come up with different results then analysing the reasons for the differences could quickly indicate that this line of inquiry is a dead end or it could throw up new questions worth exploring.
    • Larger combined cohorts - the current studies often have far too few participants; pooling truly comparable data from several teams would allow for a sort of meta-analysis with more statistical power.
    • More attractive to funders (?) - formal international cooperation and the promise of more conclusive results should be attractive to funders in the individual countries; alternatively a joint bid may also allow for example NZ to tap into UK or US funding.
     
  18. Ravn

    Ravn Senior Member (Voting Rights)

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    I can kind of see that knowing how hard and often you can exercise could be useful for people with very mild ME who wish to exercise for general health without risk of crashing. Though I suspect they don't need an exercise prescription so much as a rest-between-exercise prescription, pacing in other words.

    For the rest of us I don't quite see the point of exercise, prescribed or otherwise. We tend to spend all the energy we have anyway and any energy spent on exercise can't be spent on other, more important activities. I do actually do a few stretching exercises to prevent pain from old injuries flaring up but apart from that the trade-off between exercise and other activities doesn't feel worth it.

    That trade-off would only become worthwhile if exercise could actually increase our ability to exert, maybe with the help of some drug in the future, but right now that's not the case. Until it is I'd prefer any CPET studies to concentrate on figuring out what's going wrong during and after exercise rather than on trying to create 'safe' exercise prescriptions.
     
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  19. Snow Leopard

    Snow Leopard Senior Member (Voting Rights)

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    Yes. The variability suggests that the high heart rate itself is not the problem, but instead is adaptive compensation by the autonomic nervous system. (this was commented on in the recent video/talk by Lucinda Bateman)

    This is true, but in principle NIH grants can go to researchers in other countries, provided the research is in the interests of the USA.

    Identical methodology isn't always ideal, I like the fact that each group tries to add their own unique twist.

    We've had over 10 studies with the same findings, with similar CPET protocols, the way to move forward is varying what is measured in the protocols. I'd like to start by focusing on differences in motor unit recruitment for example, using electro and mechanical myography. Which in turn can be influenced by increased activity by peripheral afferents - which can be modulated using pharmacology. I also wonder what is possible in terms of (non-invasive) spectral imaging of metabolites in the muscle. The key point is that the microenvironments in the muscle are different to that of arterial circulation and can hypothetically reveal differences that blood testing is unable to reveal.
     
    Last edited: Oct 15, 2020
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  20. Ravn

    Ravn Senior Member (Voting Rights)

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    Yeah I didn't mean repeating the same studies that have already been done repeatedly. More that going forward - say looking at motor unit recruitment - they should do so in a coordinated fashion so as to maximise the results they each get from their 10 or so participants.
     
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