Todd Davenport discusses the overlap between Long COVID and ME/CFS, emphasizing differing pathogens, bioenergetic dysfunction, and diagnostic challenges, while advocating for patient history, symptom validation, and pacing strategies for management..
Guest – Professor Todd Davenport
Note: The podcast has no bias. All conflicts of interest are highlighted with individual guests.
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Podcast Overview:
Todd Davenport explores the relationship between Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), focusing on the pathogens involved, bioenergetic dysfunction, and the diagnostic challenges posed by these conditions. It emphasizes the importance of thorough patient histories, symptom validation, and effective management strategies, including pacing and energy conservation techniques..
Comparison of Long COVID and ME/CFS Pathogens:
- Detailed analysis of how the viruses that cause Long COVID and ME/CFS differ.
- Exploration of the viral mechanisms and their impact on the body’s systems.
Bioenergetic Dysfunction in Both Conditions:
- Examination of how both conditions lead to disruptions in cellular energy production.
- Insights into mitochondrial dysfunction and its effects on fatigue and other symptoms.
Diagnostic Challenges and Criteria:
- Overview of the difficulties in diagnosing Long COVID and ME/CFS.
- Discussion of the overlapping symptoms and the need for specific diagnostic criteria.
- Importance of differentiating these conditions from other similar illnesses.
Importance of Patient History in Diagnosis:
- Emphasis on taking comprehensive patient histories to understand the onset and progression of symptoms.
- The role of detailed patient interviews in identifying patterns indicative of Long COVID or ME/CFS.
Strategies for Symptom Validation and Management:
- Approaches to validate patient symptoms to ensure they are taken seriously by healthcare providers.
- Practical management strategies to alleviate symptoms and improve quality of life.
- The significance of a patient-centered approach in managing these conditions.
Advocacy for Pacing and Energy Conservation Techniques:
- Explanation of pacing as a crucial strategy to manage energy levels and prevent crashes.
- Guidance on implementing energy conservation techniques in daily activities.
- Encouragement of patients to listen to their bodies and avoid overexertion.
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Podcast Transcript:
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Episode 6 – PEM, Long COVID and It’s Management ft. Professor Todd Davenport
[00:00:00] Funmi Okunola: The information in this podcast is provided for informational purposes only. You should not use any information discussed in this podcast and related materials to make medical or healthcare related decisions. Always consult your physician or other qualified healthcare provider with regards to diagnosing and managing your medical condition. Any medications or treatments, including any discussed in this podcast should be initiated and managed by a qualified healthcare professional.
Funmi Okunola: Welcome to “Long Covid – The Answers”. Today’s Episode is entitled “Post Exertional Malaise (PEM), Long COVID and its Management”. I’d like to introduce Professor Todd Davenport. Professor Davenport serves as Professor and Vice- Chair of the Department of Physical Therapy in the School of Health Sciences at the University of the Pacific in Stockton, California, USA, where he teaches in the Doctor of Physical Therapy program.
He also has a Master’s in Public Health obtained at the University of California, [00:01:00] Berkeley. Professor Davenport has served on the Multi-disciplinary Primer Writing Committee of the International Association for Chronic Fatigue Syndrome, Stroke, Myalgic Encephalomyelitis, and as a contributor to World Physiotherapy’s Long COVID Briefing Paper on Safe Rehabilitation Approaches for People Living with Long COVID.
He is an Education Co-Chair of Long COVID Physio, which has an excellent website. Welcome, Todd.
Todd Davenport: Thank you. Thank you so much for having me and thank you to your viewers and your listeners. I appreciate the chance to be here.
Funmi Okunola: Thank you. Todd, do you have any conflicts of interest to declare?
Todd Davenport: You know, I do.
I have the opportunity to work with a lot of talented people, some of them are at the Work Well Foundation, where I serve as Scientific Advisor. I’m also the founder of Work Well Health, where we do clinical services with individuals who have Post Exertional Malaise.
Funmi Okunola: Thank you. Today’s interview is based on a series of free blogs given by Professor Davenport called “Lessons from Myalgic [00:02:00] Encephalomyelitis Chronic Fatigue Syndrome for Long COVID”, published in the Journal of Orthopaedic and Sports Physical Therapy in February of 2022, and also Long COVID Physio’s video on pacing.
Firstly, Todd, what is PEM? Can you explain the clinical staging of Post Exertional Symptoms?
Todd Davenport: I can. So, Post Exertional Malaise is known by another term, Post Exertional Neuro Immune Exhaustion. That’s really the understanding that I’m following from here with this explanation.
You can find that in the Carruthers et al paper in 2011, describing the international consensus criteria to identify Myalgic Encephalomyelitis. Post Exertional Malaise, as everyone calls it, is a constellation of symptoms and signs that follow an exertion. That exertion doesn’t have to just be physical, it can be cognitive, it can be emotional, it can be environmental.
[00:03:00] What’s most commonly discussed is fatigue, but the fatigue in Post Exertional Malaise is the feeling of nothing left, not being able to get up. Some people refer to it as bonked, like after a marathon. But the marathon was washing your hair or brushing your teeth. We talk about the fatigue, but there’s a whole host of other symptoms and signs that make up Post Exertional Malaise, like cognitive dysfunction.
You hear people thinking, talking about it, like thinking through jello, so limited short-term attention and memory. Sleep disturbances that no one with Post Exertional Malaise that I’ve ever met sleeps deeply or well, widespread body pains, causing a common comorbidity to be Fibromyalgia, weakness, numbness and tingling, headaches, even signs and symptoms of illness like viral reactivation, so fevers and swollen glands, and sore throats after exertion. It’s usually delayed. It can be [00:04:00] delayed. The onset of Post Exertional Symptoms and signs can be anywhere from a day to maybe three days after the triggering activity, which really confounds the understanding of what may have caused any given exacerbation.
The recovery is prolonged. Our group has shown that failure to recover from an activity within 24 hours is an important marker that differentiates being out of shape from Post Exertional Malaise, and there’s commonly a progressive lowering of functional baseline. So, I’ve heard people with Post Exertional Malaise talk about this like ‘their world becomes smaller’. So maybe they’re able to do some remunerative work at first, but that’s all they’re able to do. They’re not able to do social events. They’re not able to engage in the family sphere. Soon they’re not able to work as much, soon they’re not able to leave the house as much, soon they may not be able to leave the bed as much.
So, there’s this progressive shrinking of one’s world that happens with Post Exertional [00:05:00] Malaise. As for the staging, there are certain symptoms that begin that we think are more immediate. There are symptoms we think that are more short term and ones that are more long term.
This is related to our research as well as our clinical observations of many people who have undergone cardiopulmonary exercise testing, which is a form of physical exertion, and the immediate Post Exertional Malaise is very similar to over exerting, but just extra in intensity and unexpectedly low intensities like brushing your teeth or rolling in the bed.
If you’re very severe, these are fatigue again. Fatigue does not do this justice. People report being disproportionately out of breath, dizzy, nauseous. In short term, Post Exertional Malaise is a consequence of overdoing things once for a sufficiently prolonged period of time, which may just be a few minutes, or overdoing things repetitively throughout the day or over [00:06:00] successive days.
These short-term Post Exertional Malaise symptoms are brain fog or cognitive dysfunction, muscle and joint pain, headaches, and sleep disturbances. Then long-term Post Exertional Malaise involves symptoms that last for a week or more, and seem to reflect pretty significant physiological dysfunction involving weakness, decrease in function, immune reactivation and cardiopulmonary symptoms like palpitations, and increase in worth of static intolerance.
So, I think the take home message here is that you know, Post Exertional Symptoms and signs are highly unusual. In fact, when I first started working with this patient population, it was just really hard to believe that all of this is happening, but that the patient has a high degree of credibility, and we really should be listening to them.
Funmi Okunola: There’s over 200 symptoms associated with Long COVID. You’re almost saying that a huge collection of those [00:07:00] symptoms are part of the whole Post Exertional Malaise spectrum? My impression was that you have Post Exertional Malaise which has a specific cause, brain fog, which has another, headaches, another, etc. so forth. But you’re saying that it could be part of the same pathophysiology, i.e. disease-causing process, all under the umbrella of Post Exertional Malaise?
Todd Davenport: Yeah. So, there are lumpers and there are splitters. I think the splitters have gotten out and cataloged the symptoms that are associated with Post-acute Sequelae of COVID-19 or Post COVID condition.
However, we want to call this umbrella phenomenon that we see, but as I read those first works by Hannah Davis and her colleagues, starting to catalog those 200 symptoms, I saw tons of commonalities with regard to what we’ve seen for many years with ME/CFS. So, yeah, interestingly enough, one of those 200 symptoms is Post Exertional Malaise or Post Exertional Symptom [00:08:00] Exacerbation, and I don’t really think about that as its own symptom – its own cluster of signs and symptoms, and I think one of the things that impairs clinical identification and even research into this Post COVID condition, this Post Acute Sequelae of COVID-19 is thinking about Post Exertional Malaise as its own thing. In fact, I think the term that is preferred in the patient community among people living with Long COVID is Post Exertional Symptom Exacerbation, which is part of the international consensus criteria for ME, just meaning that symptoms are exacerbated with a prior exertion.
But that’s just one component of Post Exertional or immune exhaustion or what’s commonly known as Post Exertional Malaise. So, I would encourage us to start to think about these signs and symptoms less as individual things affecting individual systems and organs and looking at these commonalities that can be really critical for people’s [00:09:00] quality of life.
Funmi Okunola: So, I’ve asked this question several times with several interviewees because the Canadian Consensus Criteria, which was developed in the early 2000s for ME/CFS, closely matches the presentation of Long COVID, and I’ve asked both Dr. Amy Proal and Professor Danny Altmann as to whether these are one and the same disease. What’s your opinion on that?
Todd Davenport: I think there’s a lot of overlap. My sense is that they aren’t precisely the same disease. So, there are a couple of things that lead to that. The first is that the precipitating pathogen is known and potentially different.
I have a hunch that it causes a very similar pathophysiologic cascade. But I think if it’s caught early enough, in the process, preventing that process from moving forward is going to depend on the pathogen that [00:10:00] I think that’s a pretty common thought in the viral persistence community.
My sense is that we may be catching the process too late. Once a person has Post Exertional Malaise, it strikes me that this is a different process that can’t fully be explained by viral persistence, and I would also say that the way we have defined the Post COVID condition, Post Acute Sequelae of COVID-19 opens us up for a host of different conditions under the umbrella, involving end organ damage that would not necessarily be subsumed under the Canadian consensus criteria.
So, for example, people who have Cardiopulmonary conditions directly related to the pathogen itself, wouldn’t necessarily fall under the umbrella of having Post Exertional Malaise. But I think there is some emerging evidence suggesting that there’s some substantial overlap of the Canadian consensus criteria and the international consensus criteria, and a healthy proportion of people [00:11:00] with Long COVID, particularly folks who have a little bit longer duration of the disease.
Funmi Okunola: So are you saying that people could be developing two diseases concurrently, from SARS-CoV-2; i.e., they could be developing Long COVID and ME/CFS.
Todd Davenport: Yeah, I think Hickam had it right when he said that a patient can have as many diseases as they darn well please!
So, I do think that there may be parallel processes or even a serial process in which an infection leads to a common pathophysiological pathway, whether that may be in common, whether you’re talking about an initial infection with SARS- CoV-2, or Epstein Barr virus, or Q fever, or any number of different infections that have been associated over time with ME/CFS.
Funmi Okunola: Yeah. My understanding from that, and I’ve heard from other scientists and healthcare professionals, is that for a [00:12:00] proportion of the population, a pathogen, i.e. a virus, a bacteria, or a parasite can be any of those infected processes that gets into their body. For most of us who experience that, we get sick, and we recover, and we go on with our normal lives.
But for a significant proportion of the population, which can be anywhere from 5 to 30%, that doesn’t happen, and the immune system responds in a way with a cascade of inflammation and biochemical processes to cause illnesses like ME/ CFS or Long COVID, and depending on what the initial virus, bacteria, whatever it is, will depend on what, and also, I guess people’s genetic makeup, the previous exposure to disease, and the environment that they live in, will depend on how their body responds to that pathogen.
So, there’s maybe a range of symptoms that you will get and then ones that differ depending on what the infectious agent is. Does that sound sensible? [00:13:00]
Todd Davenport: Yeah, I think that sounds very sensible. Of course, we don’t have any of those precipitating triggers worked out for sure, and I know that there’s rightfully a focus on the immune system and immune dysfunction, but as a Physical Therapist and as an exercise scientist, one of the things that Post Exertional Malaise is to me is a bioenergetic phenomenon. So, it’s almost as though the virus has hijacked the cellular machinery of energy production and utilization so there is not enough left over for daily functioning. That’s where my research and clinical interests have been over time. I think some important corollaries from that related to how we start to help people who are living with Post Exertional Malaise.
Funmi Okunola: Thank you. That was a really interesting discussion. I’m going to get back to PEM now. I think you’ve just partially answered this with your question, but what is the physiology behind Post Exertional Malaise?
Todd Davenport: I like to use this analogy, and it’s the analogy of [00:14:00] the plug-in hybrid car, and so if your listeners have heard this, I think I’ve used this before.
I don’t know, just about everyone I’ve talked with, but it’s just so handy to understand how the body produces and utilizes energy. If you asked me to explain the function of a plug-in hybrid car any more deeply than what I’m about to do, I won’t be able to do it.
So, I’m just going to warn your listeners now, but a plug-in hybrid car has two fuel sources. It has a battery, and it has a gas motor, and those fuel sources are used for different uses of the car. So, the battery is used for moving along flat surfaces and stop and go traffic. The gas motor is generally used for going up and down hills, going freeway speeds, hauling people, hauling gear, and also it can charge the battery. So, you have a short term, low intensity energy system which is the battery, and you have a stronger intensity, longer term energy system which is your gas motor. [00:15:00] The gas motor in people with Post Exertional Malaise just doesn’t seem to be working properly.
So, if you think through the analogy then with a gas motor that doesn’t work well, what do you lose? Well, you lose the ability to do longer term, higher intensity activities, and you lose the ability to charge the battery on the fly. So that results in over utilizing the battery which risks breaking down at the side of the road because you run out of battery.
I think what I just explained was about 20 years of exercise science in Post Exertional Malaise with kind of a silly analogy. But we use two-day cardiopulmonary, and what we found is that people just don’t produce and use energy as well who have Post Exertional Malaise compared to other disease states and compared to [00:16:00] just being out of shape. In particular, the most interesting findings have been at submaximal exertion where you can’t fake it.
Submaximal exertion is a really interesting place because it’s where we function. If you’ve gone upstairs and your legs have burned and you’re out of breath for a few steps, you’ve exceeded that kind of submaximal exertion. People just tend to live there who have Post Exertional Malaise. It’s that lived experience of constantly just needing a minute after going up the stairs, except maybe times infinity.
Funmi Okunola: Oh, that’s a great analogy. It just simplifies things in a really concise way and allows you to get a picture of what people are suffering.
As I said at the beginning of the Episode, and I’m saying it again now, all of the research papers that we mentioned during this interview will be available in the show notes, but I’m going to refer to a piece of research that was done fairly recently entitled[00:17:00] “Deep Phenotyping of Post Infectious Myalgic Encephalomyelitis Chronic Fatigue Syndrome”. I think this may well apply to Long COVID sufferers. It’s quite a granular paper and goes into great scientific depth. I think Eric Topol gives quite a good summary of it, but they have an excellent picture diagram of what they feel is the disease process of pathophysiology of ME/CFS and PEM.
They talk about how a pathogen comes in, and then lots of metabolites that are produced or not produced, which has an effect on the brain, so as a result, the motor system doesn’t work properly. So, the nerves that the brain talks to, to fire your muscles, don’t really work properly in people with ME/CFS and the heart and the lungs don’t respond as well from this automatic or autonomic nervous system, and that leads to pain. What’s your feeling about that paper and their discovery?
Todd Davenport: Anyone who spent more than five minutes on my Twitter feed knows about this, and how I feel is not as [00:18:00] charitable. I think their linkages are highly speculative. I think it’s very early.
I think they’ve made some links that are not helpful based on data that’s incomplete. This is probably not the example of a paper that I would use to highlight the mechanisms of Long COVID or Post Exertional Malaise in ME. The Rob Wüst paper from the Netherlands on the other hand, is I think a really good paper that provides a little bit more focused, a little bit narrower, but still, I think good quality data that we can rely on to show that there are some changes in skeletal muscle structure and function in terms of the bio-energetics of the Krebs cycle, that are impaired in the Post Exertional state compared to folks who are out of shape.
Funmi Okunola: Okay, that’s a very interesting perspective. But yes, I am also aware of the other paper from Amsterdam, which I felt was excellent because they took actual samples of muscle, didn’t they, from the thigh before [00:19:00] exertion and after exertion of people with Long COVID and showed that there was damage, which really backs up the fact that pushing people, graded exercise is inappropriate and can be dangerous for sufferers.
So yeah, I thought that was an excellent paper.
Todd Davenport: Absolutely.
Funmi Okunola: Todd, how do you diagnose Post Exertional Malaise?
Todd Davenport: Well, our data over time has supported that William Osler’s old dictum that if you listen, the patient will tell you their diagnosis is true. About 12 years ago, we showed that reports of severe fatigue plus the cluster of symptoms, including Neuroendocrine Dysfunction.
So, weakness, immune dysfunction, sore throat, swollen glands, pain and sleep disturbances were highly discriminative between people with ME versus deconditioned people, and just recently we simplified the approach to say, hey, if a person only has one or two unusual symptoms from a whole menu, that’s enough to differentiate me from [00:20:00] deconditioning.
So just listening to patients goes a long way, and I think the science vindicates us in validating a patient’s unusual lived experiences following exertion. But outside of that, there are a number of promising study results that may turn out to be biomarkers.
We’ve seen different types of blood tests, different types of biochemical analyses and so forth, but we don’t have one that’s been fully validated for use in a primary care provider’s office yet. We’ve published, as I mentioned, a lot on sub-maximal exercise dysfunction on two-day cardiopulmonary exercise testing along with the symptoms and signs of Post Exertional Malaise as a marker, and this can be helpful because here in the United States, at least it’s admissible evidence in social security disability cases that adjudicate disability, acknowledging that cardiopulmonary exercise testing should be used on an individual basis with appropriate cautions, with experienced folks doing the testing and really should be considered on a case by case basis.
Funmi Okunola: Did you tell our non-medical [00:21:00] viewers and listeners what a cardiopulmonary exercise test is?
Todd Davenport: Yeah, just put simply, it’s a test in which you’re on a cycle ergometer. So, one of those exercise bikes and hooked up to an EKG. You have a mask in the tube, in your mouth that connects to a computer that analyzes the gases that come out of your mouth during the test.
We ask you to start pedaling at a constant rate, and then during the task the bike pedals get a little harder to pedal. So, there’s this sort of gradation of resistance there. The test lasts usually from maybe 6 to 12 minutes. That’s one type of cardiopulmonary exercise testing. There’s a bunch, but that’s the kind that we generally use. Then what makes the Work Well Foundation’s protocol unique is that we come back 24 hours later, and we do the same test. Then we compare performance on the two tests.
Funmi Okunola: That’s great. Thank you for that explanation.
So, my next question really is, as a Family Physician, I don’t have immediate access to something [00:22:00] like that. Probably a Physiotherapist in Vancouver or department that’s able to do that, but the wait list will be a mile long. So apart from the great medical edict of “listen to your patient” because you’ve reminded us that 70% of our information comes from the patient’s history when we’re assessing and it’s about listening; are there other methods of diagnoses that can be applied in the Family Physician’s office that you would recommend?
Todd Davenport: Well, being a Physical Therapist, I want to tread lightly here, understanding that being a Family Physician is not my background. But what I have seen used to great effect is, after identifying whether a person might fit relevant case definition criteria for Post Exertional Malaise, providing validation of that diagnosis, doing things like assessing Orthostatic Intolerance, a treatable aspect of the disease, doing testing for Mass Cell Activation Syndrome, which is potentially [00:23:00] prevalent in this population, being alert for symptoms and signs of Cranio-surgical instabilities or Joint Hypermobility Syndromes that also may be addressed with your rehab colleagues, could be helpful as well.
So, while there is no approved test and no approved cure for Post Exertional Malaise, there are treatable aspects of this clinical phenomenon that can improve people’s quality of life.
Funmi Okunola: So, then you’re saying that if we try and diagnose things in the office that might be associated with Post Exertion Malaise, like for example, I guess we could use a NASA Lean test, and people can also do that at home with somebody for safety. I know for Mast Cell Activation Syndrome, doing simple things like rubbing on someone’s skin in a particular way can cause a reaction. So that might be an indicator, by finding associated things, as well as listening to the patient in the office and maybe looking at a consensus definition for Post Exertional Malaise; bringing all of that information together could make the diagnosis in the office. That would take a series [00:24:00] of consultations if you were only given 10 minutes to see a patient or maybe doing a double slot each time.
What about the person, the sufferer, keeping a journal of what’s happening to them? Does that help at all?
Todd Davenport: Absolutely, and it certainly helps me as a Physical Therapist. This sort of gets into what the Physical Therapist, Occupational Therapist can do to help – that ultimately journaling serves as a cornerstone of pacing programs and pacing being balancing activities with rest.
Again, trying not to tax the gas motor that’s dysfunctional we’ve identified already, and trying not to over rely on the battery. What we see is that there are pencil and paper ways to do it. Simple is just keeping a flip notebook and three or four times a day when you remember it – just the time of the day, what you’re doing, and how you feel. Over time that data accumulates with brain fog. It’s really difficult to journal and to keep track of things. [00:25:00] But if we can allow the paper to remember for us, then that can be very helpful, and of course there are apps on the market now that are very good for this, in terms of journaling, in terms of pairing biometric data concurrently with symptoms so that people can draw those relationships without having to put in a lot of work to remember what’s happening.
Funmi Okunola: A lot of healthcare providers label Post Exertional Malaise as being psychosomatic or as a result of deconditioning, i.e. being unfit. What’s your response to this?
Todd Davenport: They’re wrong. I think we have ample data suggesting that it’s a little like shooting fish in the physiological barrel.
There’s just so much, so many other alternate explanations that are so much better than a psychosomatic explanation at this point that thinking that Post Exertional Malaise is primarily psychosomatic is living back in the nineties in the worst [00:26:00] way. Musical tastes aside. As for deconditioning, look, we have ample evidence at the systematic review level that there are important differences between people who are deconditioned and people who have Post Exertional Malaise, and in fact I would go so far as to suggest that data. Means that people with Post Exertional Malaise do not have a normal metabolism, do not have a normal ability to accommodate and adapt to exercise. So, thinking about people as deconditioned who actually have Post Exertional Malaise can be harmful, and the harm comes in the fact that if you can’t recover from one bout of activity, like washing your hair, brushing your teeth, you’re not likely to accommodate going for a walk and then advancing that.
Walk a few minutes here and there, or when you feel like it. So here again this is an argument against graded exercise for Post Exertional Malaise.
Funmi Okunola: Thank you. What is pacing?
Todd Davenport: So pacing is balancing activities [00:27:00] with rest. It’s a way to reduce tax on that gas motor, the impaired, aerobic metabolism.
It’s an opportunity for people to make voluntary judicious decisions about how to use their energy instead of letting their body crash and decide. Now, if you’re in the severe range, pacing is hard when the offending physical activity is rolling over in bed or getting up to use the bathroom once a day or having a sponge bath or something like that.
So, pacing generally is a little bit more helpful in the mild to moderate phases of the disease where there is still that ability to voluntarily allocate energy towards desired activities.
Funmi Okunola: Okay. So how does it work practically. I’m a listener here or a viewer, and I’m trying to work out how I can apply pacing to my everyday life. Could you give a practical explanation, [00:28:00] and what is the energy envelope?
Todd Davenport: Yeah. Energy envelope just means keeping activities within your abilities.
Funmi Okunola: Thanks. I think the first step is to acknowledge that pacing is hard work. Everyone thinks that pacing is doing less and say they think about pacing is less.
Todd Davenport: The pacing actually takes a lot of hard work. It takes a lot of self-examination of one’s own activities. It takes a lot of thinking through what a person values in terms of their functioning, and the kinds of things they want to do – the person they want to be, and the things they’ll want to prioritize.
Balancing different types of health concerns, some of which may respond to exercise, but exercise might not be possible because of the Post Exertional consequences. I think just acknowledging that there is some set up and some lifestyle modification that’s important.
This is where I think the clinicians listening in rather than thinking about pacing is helping someone with pacing on an episodic basis for a few visits here [00:29:00] and there kind of masked within a certain time period. We need to start thinking health coaching models for people.
More prolonged we need to think about effective models of behavior change, but not to do more exercise, which is what we commonly think of, but to engage in seeking and enacting this balance between activities and rest as part of that set up. I think we’ve talked about it a little bit already – take notes.
Funmi Okunola: We’ve talked about the paper log. We’ve talked about apps getting insights as to the different types of activities and how they may affect your body is really important. Having that data is going to be critical, in order to make those decisions in terms of balancing activity and rest.
Todd Davenport: I think consistently when I work with people on pacing programs that it’s important to give yourself permission to do less. Doing less is not being less. It’s actually being more in a lot of ways – give yourself permission to feel better. That involves a lot of working against prevailing social attitudes towards what we think about [00:30:00] as being industrious productive and so forth.
It’s a lot of unpacking some personal ideas about being worthwhile. Even if you were making some short-term sacrifices in the attempt for a better balance. I think as such building a community around you whenever you can that encourages your pacing, helps your pacing.
At the risk of being a little bit contemporary in my reference fills your cup. I think these are things that are important, but really difficult to do. Because as we talked about earlier, Post Exertional Malaise tends to narrow your social circles a lot.
Making sure that, as much as possible, the people around you are supportive of your lifestyle I think are critical.
Funmi Okunola: I love the term “health coaching”. I’m going to use that one. I will quote you; I promise. So, can you also explain the practicalities of pacing with regards to heart rate bio-sensitivity and anaerobic threshold?
Todd Davenport: Absolutely. So anaerobic threshold is the point at which your aerobic [00:31:00] metabolism becomes defeated and doesn’t work as well. It’s hard to function above your anaerobic threshold, and what we notice is that people with Post Exertional Malaise, their anaerobic threshold drops after they’ve exerted previously.
So, we think this is part of the reason why there’s a sort of an up and down or a waxing and waning window of function for people. It’s literally because their physiology is different. In fact, when I first started looking at this 12 years ago, they showed me these two-day CPETs that in the first day person looked totally different than the second day person.
I thought, how could this possibly be? These are two different people, and of course, my work well colleagues said, “Nope, same person, 24 hours different”. We don’t see that in deconditioning, obviously, and we don’t see that in Psychosomatic Phenomenon either. Again, your submaximal exertion is not something that you can fake.
So, what we do is we try and find a marker of that anaerobic threshold, and so we select heart rate because it’s easy. We think that the submaximal exercise [00:32:00] dysfunction is primarily being the oxygen you consume and the workload that you can do at that anaerobic threshold.
But heart rate is also an important marker because you can measure it on commercially available wearables. So, knowing where your heart rate is at anaerobic threshold is one way to get real time feedback about your activity intensity, and to make decisions within the moment about how you want to allocate your energy. If you’re over your 80, it’s time to rest. If you’re under your 80 potentially okay to continue.
Funmi Okunola: And how do you work out that heart rate threshold?
Todd Davenport: So, we would use the heart rate at anaerobic threshold on the second day of a two-day cardiopulmonary exercise test. But you can also take your resting heart rate, which is the heart rate that you wake up with. So, wake up before you get up and look at your heart rate. Add 15 beats to that. So, heart rate, resting heart rate plus 15. [00:33:00] That’s one way to do it. There are some other ways to do that. We can put in the show notes. But the resting heart rate plus 15 is the simplest, and it’s the most conservative way to think about your heart rate at anaerobic threshold for a pacing program.
Funmi Okunola: When we talk about aerobic for our non-scientific viewers and anaerobic, can you give some explanation to that? Because it’s when the muscles use oxygen and when they don’t.
Todd Davenport: That’s right. So aerobic metabolism is your gas motor. This is your long-term higher intensity energy system using fats and sugars. Essentially, you kind of burn them in the presence of oxygen. For the clinicians out there, it brings to mind, recollections of the Krebs cycle. We all try and block out because it’s one of the first very complicated things that you learn, but it turns out to be very important for this.
Your aerobic metabolism is very efficient. It nets a lot of energy, but it’s only so good for so long because the byproducts of the process end up defeating the process, and [00:34:00] it’s not as good anymore and end up trying to burn those sugars and burn the byproducts of using oxygen to burn sugars and fats.
That’s at the very end. You do that without oxygen so that would be considered anaerobic metabolism. You can’t do that for very long and it’s very uncomfortable. But it seems as though people who have Post Exertional Malaise, ME, Long COVID, they live in anaerobic metabolism.
Funmi Okunola: Yeah. So, the whole idea is once you set that heart rate threshold that you don’t go beyond it so that you don’t tip into the anaerobic threshold and get very ill and regress. So no, that’s fantastic. How does a Physiotherapist help someone with PEM prevent or alleviate their condition? So, I’m thinking about what you do as a health care professional practically for people in this instance in your clinics.
Todd Davenport: Great question. Pacing, pacing, and more pacing. Again, a health coaching model is important. This is a lifestyle change. This is a change in [00:35:00] how a person makes decisions about their life. Again, for my Physical Therapists, Occupational Therapists, Rehab Medicine colleagues out there, we’re not thinking about episodic care. We’re thinking about the long term here – this is a long game. In addition, providing advice, reinforcement, troubleshooting, problem solving on some of the treatable aspects of the conditions such as Orthostatic Intolerance Tachycardia Syndrome.
Finding the appropriate stockings, how to get the right amount of salt in the diet. These kinds of things that we consistently troubleshoot with people of ways to compensate or provide splinting, or if appropriate, very, very cautious exercise for people who have Joint Hypermobility Syndromes and so forth.
So, there’s a lot that we can do in order to help improve quality of life, even though we don’t have the gold standard testing and treatments yet.
Funmi Okunola: That’s great and really positive. We need to clone [00:36:00] you. Thank you, Todd, for such a fantastic interview. It’s really informative, very enriching, and thank you for all your hard work and advocacy for Long Haulers and those with ME/CFS.
Todd Davenport: Really appreciate the chance to be on with you today. Thank you for inviting me and best of luck to everyone. Thanks.
Funmi Okunola: Thank you again, and please join us next week for another Episode of Long Covid – The Answers.
Funmi Okunola: Some questions for listeners to consider.
What are your top five takeaways from this episode?
How will this episode change your practice or perception of this disease?
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SHOW NOTES:
Professor Todd Davenport is the Professor and Vice Chair of the Department of Physical Therapy in the School of Health Sciences at the University of the Pacific in Stockton, California, USA is interviewed by Dr Funmi Okunola about Post Exertional Malaise in Long COVID and ME/CFS.
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7. Energy saving tips fact sheet
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