I struggled for 5 days after 3 mile walk 8 days ago. Then I went for a 2 mile walk yesterday after a few shorter walks on intervening days. Now I'm tired as hell. This is the same 2 mile walk that I did a month ago and I didn't suffer from post-exercise fatigue then -- I was able to run errands the next day. The improvement that started on 6/23 is definitely fading, at least partially.
You'd think, if the improvement was from the diet change and subsequent lowering of ambient inflammation, it should be lasting as long as I'm on the same diet. Conversely, if it is fading, maybe it was from something else. But what would that be?
Over the years I (and my wife) noticed that my condition temporarily improved whenever I changed my environment. When we moved back from Korea in 2014, for instance, I was able to walk more than usual without getting sick. That, despite the fact that moving, across the ocean no less, is a lot of work. We also stopped in Philippines on the way back because the flight was cheaper that way and we figured we'd make a vacation out of it despite my apprehension about doing too much. To my surprise I did just fine. (Or, as fine as I could do under the circumstance). We went snorkeling one day and then a long trip to Sumilon Island to see whale sharks. Activities mostly involved floating around in the water and nothing more. Still, they were all day trips that took a lot of energy. The all-day flight afterward and dragging along 60 lbs luggages was no picnic either. Yet, I did not get sick.
This type of improvement usually last a week and then dissipates as I settle back into routine and novelty wears out. It's as if I'm less likely to get sick when I'm excited. (As long as I don't over-do too much, that is.) This improvement could be brought by extra dopamine counteracting fatigue-inducing 5-HT or reducing the inflammation sensitivity. (I'd predict, based on this dopamine theory, that dopaminergic drugs would have some effect for CFS patients, but that has been already shown).
Was the last improvement caused by this? 2 days before I started seeing the improvement, I had my Internet disconnected. That stopped me from reaching for my phone every a few seconds and brought some measure of peace. It also motivated me to commute to coffee shops a couple blocks away, twice a day. I couldn't live without the Internet altogether, after all. That broke up my normal routine and the cold air in the morning made me feel as if I was going back to work.
Bruce Campbell proposed the idea of energy envelope as part of the pacing strategy. The idea was to view how much you can do without triggering the post-exertional sickness as the energy, and then figure out ways to expand that energy. With inflammations sensitivity theory, you could also view this envelope as the inflammation zone in which you could exercise without getting sick. And then the pacing becomes about managing the inflammation rather than managing the energy.
There would be 2 ways to push this envelope and increase the safe inflammation zone. At the top, you could improve by raising your tolerance to exercise-induced inflammation. And, at the bottom, you could increase the zone by reducing ambient inflammation and thereby making more room for exercise induced inflammation.
The improvement that I saw could be the combination of the two: the diet change lowered the floor of the envelope by reducing the ambient inflammation and the routine change caused by Internet disconnection raised ceiling by reducing the sensitivity. And the combination of the two may have made made the improvement bigger and last longer, making me think for a while that I was recovering.
It seems there are more than one way to lower the floor. There have been patients reporting improvements after taking supplements or practicing meditation. The supplements that they report are often anti-inflammatory. Meditation is also anti-inflammatory. So it's possible they work by lowering the ambient inflammation and thus increase the activity envelope. None of these worked for me, so it is also possible that certain remedy works for certain people.
As for the raising the ceiling, I haven't found any other than breaking off from the routine. If someone finds a way to raise the tolerance and keep it there, that would constitute a cure.
Saturday, July 30, 2016
Monday, July 25, 2016
Distance vs. Speed, Again
So, how is it possible that the walking distance can improve drastically, but not the speed? I previously described how the speed can make a big difference using metabolite build-up to make the case. Not only the metabolites build up much faster at slightly higher speed, the body has to work harder against the headwind provided by the metabolites. Faster speed hence can result in post-exertional sickness more readily than longer distance.
It turns out, however, metabolites don't build up at below the anaerobic threshold. So, unless you can make the case that AT is much lower for CFS patients, the metabolite argument does not hold. And there is no reason to believe that is the case. Hence I proposed it is myokines, not metabolites that builds up and creates the headwind against exercise even at lower speed.
The metabolite buildup at higher speed could be creating the headwinds by taking the same pathway: it may be resulting in inflammation mediated by the inflammasome activation. (This paper makes me wonder if my switch to brown rice reduced SCFA metabolite, and therefore lowered the ambient inflammation level, resulting in the improvement that I've seen. The switch to the brown rice was to reduce triglyceride after all, and SCFA seems to be the precursor of triglyceride).
The distance increase of 100% is equivalent to 5% increase of the speed in my experience. Since I used to be able to walk 1 km at the speed of 98 steps/min on a flat terrain without triggering the post-exertional sickness, I should be able to do about 102 now. This is a concrete prediction that I can test.
(One problem with counting steps is that, the stride tend to increase with the speed as well. So, your speed could be increasing twice as fast as the number of steps at low speeds. You should take that into account if you are resorting to steps/min method to pace).
In any case, the post-exercise fatigue from the 3 mi walk on Friday has come and gone as expected. Now the post-exertional funk set in and I'm wondering if I should walk today or not. I really should give another day for the recovery from the 3 mile walk 2 days ago. 3 mi walk may be too much since I can't recover from it with 48 hour rest. I'll have to stick to less than 2.5 miles.
It turns out, however, metabolites don't build up at below the anaerobic threshold. So, unless you can make the case that AT is much lower for CFS patients, the metabolite argument does not hold. And there is no reason to believe that is the case. Hence I proposed it is myokines, not metabolites that builds up and creates the headwind against exercise even at lower speed.
The metabolite buildup at higher speed could be creating the headwinds by taking the same pathway: it may be resulting in inflammation mediated by the inflammasome activation. (This paper makes me wonder if my switch to brown rice reduced SCFA metabolite, and therefore lowered the ambient inflammation level, resulting in the improvement that I've seen. The switch to the brown rice was to reduce triglyceride after all, and SCFA seems to be the precursor of triglyceride).
The distance increase of 100% is equivalent to 5% increase of the speed in my experience. Since I used to be able to walk 1 km at the speed of 98 steps/min on a flat terrain without triggering the post-exertional sickness, I should be able to do about 102 now. This is a concrete prediction that I can test.
(One problem with counting steps is that, the stride tend to increase with the speed as well. So, your speed could be increasing twice as fast as the number of steps at low speeds. You should take that into account if you are resorting to steps/min method to pace).
In any case, the post-exercise fatigue from the 3 mi walk on Friday has come and gone as expected. Now the post-exertional funk set in and I'm wondering if I should walk today or not. I really should give another day for the recovery from the 3 mile walk 2 days ago. 3 mi walk may be too much since I can't recover from it with 48 hour rest. I'll have to stick to less than 2.5 miles.
Friday, July 22, 2016
Life After Improvement
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| Nothing but blue skies |
After a day of rest tomorrow, I shall take my campaign to the Fillmore neighborhood of Lower Pacific.
Thursday, July 21, 2016
Myokines,Not Metabolites
Now I'm thinking CFS is a hypersensitivity to myokines rather than metabolites. If the metabolites were the culprit, you should be able to walk a distance without the rests by keeping your heart rate below your anaerobic threshold (AT). By definition, AT is the rate at below which metabolites do not accumulate because your body can clear them all as they are produced. CFS patients, however, must take frequent rests even when walking slowly at below their AT rate to prevent post-exertional sickness. That could be because myokines accumulate at lower heart rate than AT.
This also explains why walking even a slightly faster than the safe speed triggers the post-exertional sickness. Slow walk is anti-inflammatory. But it turns pro-inflammatory when you walk faster. The fact that I get a post-exertional sickness after a few squats can be explained likewise. The paper by Yeo NH et. al. demonstrates the effects of different exercise intensity on myokines. All these taken together is yet another reason why measuring exercise type/speed would be more useful than heart rate in predicting the post-exertional sickness.
So, does it matter if CFS patients are sensitive to myokines or metabolites, or sunspot cycles for that matter? For my purpose, no. I am only after managing the fatigue, and therefore how/when of fatigue is all that matters, not what/why. What and why are the job of the scientists. But having a model for the underlying structure, even if that is only my imagination, helps me to figure out when and how of the fatigue. If you have a working model, you will know when things are not going your way. If you don't have one, well, you are just meandering in the wilderness with no direction.
This also explains why walking even a slightly faster than the safe speed triggers the post-exertional sickness. Slow walk is anti-inflammatory. But it turns pro-inflammatory when you walk faster. The fact that I get a post-exertional sickness after a few squats can be explained likewise. The paper by Yeo NH et. al. demonstrates the effects of different exercise intensity on myokines. All these taken together is yet another reason why measuring exercise type/speed would be more useful than heart rate in predicting the post-exertional sickness.
So, does it matter if CFS patients are sensitive to myokines or metabolites, or sunspot cycles for that matter? For my purpose, no. I am only after managing the fatigue, and therefore how/when of fatigue is all that matters, not what/why. What and why are the job of the scientists. But having a model for the underlying structure, even if that is only my imagination, helps me to figure out when and how of the fatigue. If you have a working model, you will know when things are not going your way. If you don't have one, well, you are just meandering in the wilderness with no direction.
Wednesday, July 20, 2016
Improvement Means Freedom
The Muni bus got stuck again. For 15 minutes this time. Before, I would have had no choice but wait. This time, however, I decided to walk. It was less than 1 km away and there was no point waiting when I would get there (almost) by the time the bus restarts. (I didn't actually walk though. I changed my mind and took a different route).
When your walking ability limited, you have to carefully plan your routes. One mistake, you can get marooned. Many times before I felt like dropping right where I was and lie down when that happened. (Once I was draped on a chair outside of a deli in a deserted section of the city, and the passing tourists, probably lost, came to check if I was alive). And many times before I felt like the Donner Party at the foot of the Sierra. With the ability to walk additional one mile, I don't have to be as careful. When the life throws a curve, I don't have to get marooned either. It means freedom.
It also means peace. I went to the library in the afternoon to use their printer. Their system was down. To make it worse, the streets just got closed when I came out, thanks to the SEIU protest. I had to walk extra 500m to catch the bus. Before, I would've thrown hands up in the air, roll my eyes and sworn like hell. I just shrugged this time.
Just a little improvement in walking ability, and the quality of life improves drastically. Conversely, it goes to show you how bad I had before the improvement. Many CFS patients have it worse than I and most people don't understand how bad that is. It's an insult to injury that CFS patients often have to deal with.
When your walking ability limited, you have to carefully plan your routes. One mistake, you can get marooned. Many times before I felt like dropping right where I was and lie down when that happened. (Once I was draped on a chair outside of a deli in a deserted section of the city, and the passing tourists, probably lost, came to check if I was alive). And many times before I felt like the Donner Party at the foot of the Sierra. With the ability to walk additional one mile, I don't have to be as careful. When the life throws a curve, I don't have to get marooned either. It means freedom.
It also means peace. I went to the library in the afternoon to use their printer. Their system was down. To make it worse, the streets just got closed when I came out, thanks to the SEIU protest. I had to walk extra 500m to catch the bus. Before, I would've thrown hands up in the air, roll my eyes and sworn like hell. I just shrugged this time.
Just a little improvement in walking ability, and the quality of life improves drastically. Conversely, it goes to show you how bad I had before the improvement. Many CFS patients have it worse than I and most people don't understand how bad that is. It's an insult to injury that CFS patients often have to deal with.
Triceps and Quadriceps
I did 6 tricep dips last night and woke up this morning with my body burning and ears popping and crackling. I had to swallowed a couple of Sudafed.
Triceps and quadriceps have been the troublemakers in my experience: use them in higher intensity and I end up with a post-exertional sickness. Tricep dips, for example, cause more inflammation even though the load is lighter than equal number of pushups. I used think that is because they are big muscles and therefore works harder. But pectoral muscles are bigger than triceps. So it must be something else affecting them. Now I'm thinking it is because tricep dips involve larger eccentric elongation that causes more damage.
They also get disproportionately afflicted with aches during the post-exertional sickness. They took a lot of abuse during my judo days and maybe they got more sensitized than other part of the body because of it.
This, again, could be born of my partiality to the hyper-sensitivity theory of CFS. But when personal anecdotes seem to fall in place, it's hard to shake it off. Impulse to weave the observations and telling the story is in our genes. That's probably how mythologies and religions were born. Science is no exception, except for the scientific process that requires any hypothesis to make testable predictions and then prove it by testing it.
Triceps and quadriceps have been the troublemakers in my experience: use them in higher intensity and I end up with a post-exertional sickness. Tricep dips, for example, cause more inflammation even though the load is lighter than equal number of pushups. I used think that is because they are big muscles and therefore works harder. But pectoral muscles are bigger than triceps. So it must be something else affecting them. Now I'm thinking it is because tricep dips involve larger eccentric elongation that causes more damage.
They also get disproportionately afflicted with aches during the post-exertional sickness. They took a lot of abuse during my judo days and maybe they got more sensitized than other part of the body because of it.
This, again, could be born of my partiality to the hyper-sensitivity theory of CFS. But when personal anecdotes seem to fall in place, it's hard to shake it off. Impulse to weave the observations and telling the story is in our genes. That's probably how mythologies and religions were born. Science is no exception, except for the scientific process that requires any hypothesis to make testable predictions and then prove it by testing it.
Tuesday, July 19, 2016
Anaerobic Threshold Method, Not a Perfect Solution
Well, I'm sure many patients have successfully employed this method to get enough exercise done while avoiding the post-exertional sickness. In my case, however, my heart rate is so variable that I would end up getting half as much exercise as I could if I kept my heart rate at 60% of the maximum.
Yesterday was an example. I strapped on my new Polar H7 and ran the usual errands. My heart rate was elevated at above 110 even just sitting in a bus. It went up above 130 when I started walking and then 140 when going up a hill. If I were to stick to 60% of my max heart rate, I should've stayed home. I walked 2 mi instead, and I'm not sick today. (This could be attributed to my recent improvement. But walking faster, even for a short distance, still knocks me out, so I'm by no means out of the woods.)
Sticking to 60% of your maximum heart rate or doing 50% of what you think you can accomplish would be a good strategy if your goal is to avoid post-exertional sickness. But if the goal is to get as much exercise as you can, we need something better. And measuring the speed by counting steps, rather than heart beats, has been a more reliable way for me. (This has been the case even when I was sicker 7 years ago). The problem is that the intensity is different on a slope and your safe speed no longer applies. (This is particularly problematic in SF with lots of hills.) That is why I slow down as much as possible on uphills, just to be on the safe side, and then resume my speed when I get to a flat terrain.
Yesterday was an example. I strapped on my new Polar H7 and ran the usual errands. My heart rate was elevated at above 110 even just sitting in a bus. It went up above 130 when I started walking and then 140 when going up a hill. If I were to stick to 60% of my max heart rate, I should've stayed home. I walked 2 mi instead, and I'm not sick today. (This could be attributed to my recent improvement. But walking faster, even for a short distance, still knocks me out, so I'm by no means out of the woods.)Sticking to 60% of your maximum heart rate or doing 50% of what you think you can accomplish would be a good strategy if your goal is to avoid post-exertional sickness. But if the goal is to get as much exercise as you can, we need something better. And measuring the speed by counting steps, rather than heart beats, has been a more reliable way for me. (This has been the case even when I was sicker 7 years ago). The problem is that the intensity is different on a slope and your safe speed no longer applies. (This is particularly problematic in SF with lots of hills.) That is why I slow down as much as possible on uphills, just to be on the safe side, and then resume my speed when I get to a flat terrain.
Monday, July 18, 2016
Decomposition of Fatigue
One thing I noticed over the years was that lots of low intensity activities spread throughout the day, like running errands at leisurely pace, made me tired like hell and sleep like a baby, yet did not trigger the post-exertional sickness. ('Lots of activities' for CFS patients, of course, a relative term that really means 'a few activities'). On the other hand, a sustained, high intensity activity, even for a short duration, can result in a post-exertional sickness. Taking 2 more steps per minute on a 1 km walk, for example, reliably produces post-exertional sickness for me even though the total calorie expenditure is substantially less than running errands for several hours. These led me to think that there are different types of fatigues.
The first and the most obvious is the fatigue that occurs immediately from the exercise. Muscle activity produces metabolites and myokines. They act on the nerve system to produce the fatigue sensation. You usually recover this fatigue within a few hours. (A short nap after a long slow walk does wonders for me).
Exercise can also produce cellular damage from oxidative stress and micro-tear of the muscle fibers. People get tired at the end of the day and needs sleep to restore their bodies from this damage they accumulated throughout the day. The repair process entails inflammation and that brings about the sensation of fatigue. CFS patients, being sensitive to inflammation, feels this fatigue at much lower level of activities. Mild/moderate form of this fatigue usually resolve within 48 hours.
Finally, there is the extreme fatigue and weakness of post-exertional sickness. Metabolites and pro-inflammatory myokines produced by working muscles manifest as the headwind to the nervous system, and the nervous system must work harder against it to maintain the performance. The CNS of CFS patients, being hyper-sensitive to this headwind, must work even harder. When the effort goes above the threshold, the post-exertional sickness results. This is a neural fatigue that can last 96 hours or more.
In summary, the fatigue is composed of: 1) exercise fatigue; 2) post-exercise fatigue from the tissue /cellular damages 3) CFS neural fatigue in the form of post-exertional sickness. These fatigues can occur in any combination, producing multiple different (temporal) patterns for recovery from them. For example, heavy activities can produce an immediate fatigue followed by post-exercise fatigue the next day, typically involving 'happy feeling'. This fatigue then can lead right into post-exertional sickness lasting several days. (This, btw, gives the illusion of 48 hour delay, instead of the usual 24 hour delay, of post-exertional sickness). Or, you could go directly to the post-exertional sickness the next day after a higher intensity activity of shorter duration. With lots of low intensity activities, on the other hand, you may recover from the post-exercise fatigue after 48 hours without the ensuing post-exertional sickness. Lesser exertion may produce only the immediate exercise fatigue, but not the post-exertional fatigue or sickness.
(Severely ill patients probably don't get the opportunity to get post-exercise fatigue. They are so sensitive to exertion, they go right into the post-exertional sickness at an activity level).
The common denominator of all these fatigues is the inflammation. Muscle activities immediately produce metabolites and pro-inflammatory cytokines. Tissue damages also results in inflammation. These inflammations apply brake and CFS patients end up with post-exertional sickness when they apply more effort than they should against this brake.
(Though the Columbia University study concluded that inflammation levels in CFS patients are not explained by the symptom severity, that could be because the sensitivity to inflammation, rather than inflammation itself, is causing the symptoms.)
So, what's the point of this decomposition of fatigue? For now, it helps me to explain the varying temporal patterns of fatigue that I have observed over the years. But it may also help me to quantitatively predict better how I am going to feel in days following activities. Eventually, I hope.
The first and the most obvious is the fatigue that occurs immediately from the exercise. Muscle activity produces metabolites and myokines. They act on the nerve system to produce the fatigue sensation. You usually recover this fatigue within a few hours. (A short nap after a long slow walk does wonders for me).
Exercise can also produce cellular damage from oxidative stress and micro-tear of the muscle fibers. People get tired at the end of the day and needs sleep to restore their bodies from this damage they accumulated throughout the day. The repair process entails inflammation and that brings about the sensation of fatigue. CFS patients, being sensitive to inflammation, feels this fatigue at much lower level of activities. Mild/moderate form of this fatigue usually resolve within 48 hours.
Finally, there is the extreme fatigue and weakness of post-exertional sickness. Metabolites and pro-inflammatory myokines produced by working muscles manifest as the headwind to the nervous system, and the nervous system must work harder against it to maintain the performance. The CNS of CFS patients, being hyper-sensitive to this headwind, must work even harder. When the effort goes above the threshold, the post-exertional sickness results. This is a neural fatigue that can last 96 hours or more.
In summary, the fatigue is composed of: 1) exercise fatigue; 2) post-exercise fatigue from the tissue /cellular damages 3) CFS neural fatigue in the form of post-exertional sickness. These fatigues can occur in any combination, producing multiple different (temporal) patterns for recovery from them. For example, heavy activities can produce an immediate fatigue followed by post-exercise fatigue the next day, typically involving 'happy feeling'. This fatigue then can lead right into post-exertional sickness lasting several days. (This, btw, gives the illusion of 48 hour delay, instead of the usual 24 hour delay, of post-exertional sickness). Or, you could go directly to the post-exertional sickness the next day after a higher intensity activity of shorter duration. With lots of low intensity activities, on the other hand, you may recover from the post-exercise fatigue after 48 hours without the ensuing post-exertional sickness. Lesser exertion may produce only the immediate exercise fatigue, but not the post-exertional fatigue or sickness.
(Severely ill patients probably don't get the opportunity to get post-exercise fatigue. They are so sensitive to exertion, they go right into the post-exertional sickness at an activity level).
The common denominator of all these fatigues is the inflammation. Muscle activities immediately produce metabolites and pro-inflammatory cytokines. Tissue damages also results in inflammation. These inflammations apply brake and CFS patients end up with post-exertional sickness when they apply more effort than they should against this brake.
(Though the Columbia University study concluded that inflammation levels in CFS patients are not explained by the symptom severity, that could be because the sensitivity to inflammation, rather than inflammation itself, is causing the symptoms.)
So, what's the point of this decomposition of fatigue? For now, it helps me to explain the varying temporal patterns of fatigue that I have observed over the years. But it may also help me to quantitatively predict better how I am going to feel in days following activities. Eventually, I hope.
Saturday, July 16, 2016
Polar H7 vs Fitbit Vs Huawei
The results are in. I took them out for a spin yesterday, and it's not a good news for activity trackers as expected. They are all reasonably accurate when you are at rest. When walking however, Fitbit over-clocked by more than 20 bps. Huawei watch, meanwhile, was pretty much dead. It was stuck at 60. (Needless to say, I'm returning Huawei back to Amazon.)
This goes to show you that, if you are CFS patients trying to pace yourself, you should get yourself a chest strap HR monitor and never rely on an activity tracker. (But we all knew that already, of course).
Fitbit could be still usable if it is consistent. I have no way of finding that out for now, since Polar H7 does not give me the access to its data. I'll post it if I figure out a way to get at them and compare with Fitbit data.
Yesterday was my 8th anniversary of getting CFS, btw. So, happy anniversary to myself!
This goes to show you that, if you are CFS patients trying to pace yourself, you should get yourself a chest strap HR monitor and never rely on an activity tracker. (But we all knew that already, of course).
Fitbit could be still usable if it is consistent. I have no way of finding that out for now, since Polar H7 does not give me the access to its data. I'll post it if I figure out a way to get at them and compare with Fitbit data.
Yesterday was my 8th anniversary of getting CFS, btw. So, happy anniversary to myself!
Thursday, July 14, 2016
Measuring Exertion, Part 3
We talked about the problem of inaccuracy of activity trackers for managing CFS. In a nutshell, CFS patients are so sensitive to exertions, that the resolution and precision of trackers, which are intended to aid healthy people to get healthier, are not adequate enough to register the small differences that are material to CFS patients.
Furthermore, there is a problem of measuring the high-exertion (for CFS patients), short-duration events. There are enough oxygen in the bloodstream and fuel in the muscles to power the activity for a short duration. Therefore, the heart rate is not raised proportional to the exertion, and the tracker tends to smooth out the heart rate and calorie expenditure over the trailing time. In other words, there is a damping effect for short intense activities. This is why a few squats or burpees, which trigger post-exertional sickness for me, hardly register on the tracker while slow walking that doesn't cause post-exertional sickness racks up tons of calories and heart rates.
Yet another problem is that activity trackers are generally designed for motion-based aerobic exercise such as walking. (There is a reason why they are called glorified pedometers). They don't perform well tracking ADLs, which matters the most to CFS patients, or light strength exercises that CFS specialists often recommends.
To summarize, the problems with activity trackers are: 1) HR and calories are not accurate enough; 2) they can't track short, intense activities and 3) they can't track ADLs and strength exercises. To get around these problems, we need an activity tracker specialized for CFS patients.
One way is to detect the activity types relevant to CFS patients and then infer the amount of exertion from the type and the speed. This is no different than what CFS patients are already doing to pace themselves except that it will be automated and more consistent. Not only that, the accuracy can be improved through statistical and machine learning technique as more observations pile up.
Let's take walking as an example. We've seen that the calorie expenditure and heart rate measured by a tracker is not accurate enough to discern the difference of a few steps per minute. But by measuring the speed instead of the heart rate or calories, we can more accurately differentiate the exertion and predict the post-exertional sickness. Below is the plot of the speed for the walk on 7/03 that caused crash (red) and 6/24 that did not (black). We see the difference in the peak speed that caused the crash.
Similarly, if we can discern the activity of washing dishes, for another example, and measure the speed of it, we could deduce the amount of exertion from it.
Turns out, there are activity trackers that do this for weight exercises and high intensity training. Theses trackers, however, are specialized for athletic training, and may not be suitable for CFS patients. They are tuned for truly high intensity activities of healthy athletes, and probably won't detect the intensities in CFS scale (which really means low intensity) and ADLs. But their existence means that the methodology is entirely possible and therefore can be adapted for activity tracking for CFS patients.
On the next installment, I'll talk about my progress with Android Wear device in implementing this. It'll take a while, so don't hold your breath yet.
Furthermore, there is a problem of measuring the high-exertion (for CFS patients), short-duration events. There are enough oxygen in the bloodstream and fuel in the muscles to power the activity for a short duration. Therefore, the heart rate is not raised proportional to the exertion, and the tracker tends to smooth out the heart rate and calorie expenditure over the trailing time. In other words, there is a damping effect for short intense activities. This is why a few squats or burpees, which trigger post-exertional sickness for me, hardly register on the tracker while slow walking that doesn't cause post-exertional sickness racks up tons of calories and heart rates.
Yet another problem is that activity trackers are generally designed for motion-based aerobic exercise such as walking. (There is a reason why they are called glorified pedometers). They don't perform well tracking ADLs, which matters the most to CFS patients, or light strength exercises that CFS specialists often recommends.
To summarize, the problems with activity trackers are: 1) HR and calories are not accurate enough; 2) they can't track short, intense activities and 3) they can't track ADLs and strength exercises. To get around these problems, we need an activity tracker specialized for CFS patients.
One way is to detect the activity types relevant to CFS patients and then infer the amount of exertion from the type and the speed. This is no different than what CFS patients are already doing to pace themselves except that it will be automated and more consistent. Not only that, the accuracy can be improved through statistical and machine learning technique as more observations pile up.
Let's take walking as an example. We've seen that the calorie expenditure and heart rate measured by a tracker is not accurate enough to discern the difference of a few steps per minute. But by measuring the speed instead of the heart rate or calories, we can more accurately differentiate the exertion and predict the post-exertional sickness. Below is the plot of the speed for the walk on 7/03 that caused crash (red) and 6/24 that did not (black). We see the difference in the peak speed that caused the crash.
Similarly, if we can discern the activity of washing dishes, for another example, and measure the speed of it, we could deduce the amount of exertion from it.
Turns out, there are activity trackers that do this for weight exercises and high intensity training. Theses trackers, however, are specialized for athletic training, and may not be suitable for CFS patients. They are tuned for truly high intensity activities of healthy athletes, and probably won't detect the intensities in CFS scale (which really means low intensity) and ADLs. But their existence means that the methodology is entirely possible and therefore can be adapted for activity tracking for CFS patients.
On the next installment, I'll talk about my progress with Android Wear device in implementing this. It'll take a while, so don't hold your breath yet.
Tuesday, July 12, 2016
Improvement, Not Recovery
So, I did slow 2.4 miles with 3 breaks yesterday. Today, no post-exertional sickness. I'm tired, but that's mostly because I stayed up last night for Amazon Prime Day scavenging for an Android Wear activity tracker and chest strap HR monitor, as well as a new phone for the wife who keeps losing hers. Some prices were absolute bonkers and I'm happy to report that I scored a Huawei watch and Polar h7 at half the price. I bought several other stuff too, but I'm returning most of them -- the half prices can be addictive and you can end up wasting money on things that you don't really need.
All that sitting up after walking 2.4 miles and only 4 hours of sleep. And then running errands in the afternoon. Yet, I don't have that nagging need to lie down. That, more than anything else, is an improvement that I can actually feel.
I still have no idea why the sudden improvement after so long. Some recovered patients attribute to various things that they did such as exercise, diet change, drug treatment, psychological therapy, immune detox, etc. I don't think anything I've done made any difference. I've been walking because walking made me feel better and sleep better, but that did not make any difference to my limit; it has not budged for almost 8 years. Every time I tried to increase the distance or pace, I'd hit the wall and drop like a fly. And I'm still dropping like a fly if I increase the speed. As for the diet change to brown rice, there is no way of knowing if that made any difference till someone does a clinical trial. So, for now, I'll just have to assume that I'm improving only because it's about time to improve. And it's not a recovery yet. It won't be till I can pick up the pace and get over the speed bump.
All that sitting up after walking 2.4 miles and only 4 hours of sleep. And then running errands in the afternoon. Yet, I don't have that nagging need to lie down. That, more than anything else, is an improvement that I can actually feel.
I still have no idea why the sudden improvement after so long. Some recovered patients attribute to various things that they did such as exercise, diet change, drug treatment, psychological therapy, immune detox, etc. I don't think anything I've done made any difference. I've been walking because walking made me feel better and sleep better, but that did not make any difference to my limit; it has not budged for almost 8 years. Every time I tried to increase the distance or pace, I'd hit the wall and drop like a fly. And I'm still dropping like a fly if I increase the speed. As for the diet change to brown rice, there is no way of knowing if that made any difference till someone does a clinical trial. So, for now, I'll just have to assume that I'm improving only because it's about time to improve. And it's not a recovery yet. It won't be till I can pick up the pace and get over the speed bump.
Sunday, July 10, 2016
Sudafed
I had a nasty infection in 2003 and my ears have been crackling and popping ever since. Doctor Bob said that it was probably an Eustachian Tube Dysfunction. The problem gets worse when I have a sinus congestion/headache or travelling on airplane. Sudafed is the only thing that alleviates the problem, so I've been taking it whenever the problem becomes unbearable.
When I got CFS, I also noticed that Sudafed also relieves the CFS body ache, at least partially. Some people thought that it was the stimulant effect of pseudoephedrine. No other stimulant does that though, so I don't think it's the stimulant effect. Rather, I think it's the vasoconstriction that does the trick.
Sudafed relieves the sinus congestion by constricting blood vessels. Whenever I take it, I can feel my hands and feet get cold and nasal cavity become icy. And it is about that time that I start feeling some relief from sinus headache, popping ears and body ache, all at about the same time. My theory is that my body is being sensitive to whatever is in the bloodstream when I'm particularly more fatigued and aching. And Sudafed squeezes the blood out of the muscle by constricting intramuscular blood vessels, resulting in some relief from the irritant.
This, of course, jibes with the sensitivity theory of CFS. I'm continuing down that path until I find an empirical evidence that contradicts it, or someone discovers something that disproves it.
When I got CFS, I also noticed that Sudafed also relieves the CFS body ache, at least partially. Some people thought that it was the stimulant effect of pseudoephedrine. No other stimulant does that though, so I don't think it's the stimulant effect. Rather, I think it's the vasoconstriction that does the trick.
Sudafed relieves the sinus congestion by constricting blood vessels. Whenever I take it, I can feel my hands and feet get cold and nasal cavity become icy. And it is about that time that I start feeling some relief from sinus headache, popping ears and body ache, all at about the same time. My theory is that my body is being sensitive to whatever is in the bloodstream when I'm particularly more fatigued and aching. And Sudafed squeezes the blood out of the muscle by constricting intramuscular blood vessels, resulting in some relief from the irritant.
This, of course, jibes with the sensitivity theory of CFS. I'm continuing down that path until I find an empirical evidence that contradicts it, or someone discovers something that disproves it.
Saturday, July 9, 2016
Measuring Exertion, Part 2
We talked about cumulative metabolite load (q) previously. This load is the resistance for the exertion to work against, rather than the exertion itself. The effort is then perception of the exertion made against the metabolite load. (The nerve system must work harder against the increasing metabolite load in order to tell the muscle to burn the same amount of fuel and maintain the constant performance level). For a sustained activity of constant intensity, we can reasonably use the heart rate as the proxy for the exertion. And if we conservatively assume a linear relationship between the effort and the exertion, we have:
effort = q * hr
(Though heart rate may also be raised to clear out the metabolites, the heart rate increase required to produce the energy during an exercise should be larger than the increase to clear the metabolites. Hence, the heart rate accounts for the exertion, but not the metabolite load, during a sustained exercise).
2x700m walk normally does not cause post-exertional sickness for me. But it does if I increase the speed. the walk on 7/3 was such a case. The comparison of effort for this walk (in red) with the one on 6/24 (in black) that did not cause the sickness is shown on the right.
We see that the peak effort for 7/3 is higher than 6/24 while the peak metabolite load is slightly lower. Since hr are similar on both dates, it must be only the patterns of q and hr that conspired on 7/3 that produced higher peak of effort.
Now, if I was walking faster on 7/3, you'd think that both q and hr should be generally higher on 7/3. That there wasn't much difference between the two seems to indicate that the tracker's heart rate and calorie measurements are not sensitive enough to account for the speed difference of a few steps/min and the higher effort peak on 7/3 must be just a coincidence. The tracker may be accurate enough for the purpose of healthy people, but it may not be for CFS patients who react sensitively to slight differences in exertion. If that difference is within the margin of error of the tracker, the tracker data would be useless.
In the next installment, we'll talk about how to get around this sensitivity problem of the tracker. To be continued..
effort = q * hr
(Though heart rate may also be raised to clear out the metabolites, the heart rate increase required to produce the energy during an exercise should be larger than the increase to clear the metabolites. Hence, the heart rate accounts for the exertion, but not the metabolite load, during a sustained exercise).
 |
| Metabolic Load for Crash vs. Non-crash |
 |
| Effort for Crash vs. Non-crash |
Now, if I was walking faster on 7/3, you'd think that both q and hr should be generally higher on 7/3. That there wasn't much difference between the two seems to indicate that the tracker's heart rate and calorie measurements are not sensitive enough to account for the speed difference of a few steps/min and the higher effort peak on 7/3 must be just a coincidence. The tracker may be accurate enough for the purpose of healthy people, but it may not be for CFS patients who react sensitively to slight differences in exertion. If that difference is within the margin of error of the tracker, the tracker data would be useless.
In the next installment, we'll talk about how to get around this sensitivity problem of the tracker. To be continued..
Monday, July 4, 2016
No Recovery Yet
I walked 700m to Philz at 100 steps/min yesterday and I'm sick today. So the sudden surge of activities last week wasn't the recovery. It still could be an improvement. I'll try slow 2mi again this week, and I'll call it an improvement if I don''t get a post-exertional fatigue/sickness. Meanwhile, it leaves little doubt that the speed is still a killer at any distance more than a block.
Sunday, July 3, 2016
Automated Adaptive Pacing
Imagine a little birdie that can tell you how you are going to feel tomorrow. Then imagine it telling you what/how much you can do on any given day. Better yet, it can even tell you how you going to feel for the next several days, hour by hour, so that you can plan activities for a week out at a time.
In the winter of 2008-2009, in the thick of the sickness, I was in a semi-delirium -- everything around me felt like a dreamscape -- and the gravity felt ten times heavier. It was a struggle to even pick up the phone to lift it to my ear. Then the condition would stabilize briefly bringing some hope for recovery. Next thing, it would tank again leaving me mumbling "why bother?".
One of the complaints by CFS patients is that their conditions are unpredictable. It can worsen for seemingly no reason and it's difficult manage when you can't predict your conditions. All you have is the adaptive pacing strategy that employs a few rules of thumbs and listening to your body to avoid over-exerting and getting sick subsequently.
Listening to your body is fairly subjective, however. In the early stages, I was constantly sick and in no shape to walk. But being cooped up inside the house day after day made me feel crappy and my sleep suffered. So I started walking slowly every other day no matter how I felt. That vastly improved both my mood and sleep. Conversely, when I walked a little faster or more because I felt I could, it almost invariably resulted in post-exertional sickness. Listening to my body has become somewhat useful only recently, and it's mostly about listening for post-exertional fatigue that can lead to post-exertional sickness.
CFS specialists recommend that you do about half you what you think you are able to. This allows enough margin of error so that daily variations and unexpected activities won't bring you down. But it also leaves half of the precious energy on the table. I've been operating at 10% of my pre-illness level, cutting it by half again doesn't leave much for activities other than taking care of ADL. And doing only 50% won't prevent the post-exertional sickness 100% of the time either, because what you think you are able to do is very imprecise, while the body's reaction to the exertion is precise.
They also recommend that you keep your heart rate below the anaerobic threshold. Going over this threshold presumably puts too much strain on the body and can trigger the post-exertional sickness. But my heart rate has been so variable that keeping it below 95 bps, my anaerobic threshold, has been an impossibility. My heart rate regularly shoot up to 120, at least according to my Fitbit, when I walk even on the days when my resting heart rate is 55.
So I have not had any useful tool to manage to avoid the post-exertional sickness other than keeping the records and maintaining a regular schedule of activities whenever possible. And it has been difficult to string together a week without getting sick. (Though, this has more to do with my lack of discipline than anything else).
That's what this project has been all about, to figure out a useful tool that can assist CFS patients in pacing their activities and avoid getting sick. And it would be useful enough if the tool can help bring up the activity level to 70 or 80% of threshold. That extra 20-30%p, combined with avoiding the sickness, can make a huge difference in quality of living.
So I got an activity tracker last year and start looking to figure out a way to manage my activities at optimal level. There has been some insightful discoveries. After looking at it for almost a year, however, I'm slowly coming to a conclusion that off-the-shelf trackers may not be accurate enough to be useful for CFS patients. We may need a medical grade monitor with higher resolution and precision. That is especially true for severely ill patients who can end up with post-exertional sickness just by walking from the bedroom to the bathroom. I'll also need something that can discern different ADLs with enough precision. But there are still a few more hypotheses (dozens, actually) that I'd like to test before moving on to Android Wear and beyond.
Unfortunately (or fortunately, I shoud say), it appears that my CFS is suddenly improving and perhaps even recovering. I have accumulated one year's worth data, so I may be able to continue with my analysis for a while. But I won't be able to test the predictions on myself anymore. If any CFS patient out there is willing to participate, I'd be happy to work with you. I may be able to help you with managing activities in the process. A second pair of eyes is always useful when you are trying to pace.
In the winter of 2008-2009, in the thick of the sickness, I was in a semi-delirium -- everything around me felt like a dreamscape -- and the gravity felt ten times heavier. It was a struggle to even pick up the phone to lift it to my ear. Then the condition would stabilize briefly bringing some hope for recovery. Next thing, it would tank again leaving me mumbling "why bother?".
One of the complaints by CFS patients is that their conditions are unpredictable. It can worsen for seemingly no reason and it's difficult manage when you can't predict your conditions. All you have is the adaptive pacing strategy that employs a few rules of thumbs and listening to your body to avoid over-exerting and getting sick subsequently.
Listening to your body is fairly subjective, however. In the early stages, I was constantly sick and in no shape to walk. But being cooped up inside the house day after day made me feel crappy and my sleep suffered. So I started walking slowly every other day no matter how I felt. That vastly improved both my mood and sleep. Conversely, when I walked a little faster or more because I felt I could, it almost invariably resulted in post-exertional sickness. Listening to my body has become somewhat useful only recently, and it's mostly about listening for post-exertional fatigue that can lead to post-exertional sickness.
CFS specialists recommend that you do about half you what you think you are able to. This allows enough margin of error so that daily variations and unexpected activities won't bring you down. But it also leaves half of the precious energy on the table. I've been operating at 10% of my pre-illness level, cutting it by half again doesn't leave much for activities other than taking care of ADL. And doing only 50% won't prevent the post-exertional sickness 100% of the time either, because what you think you are able to do is very imprecise, while the body's reaction to the exertion is precise.
They also recommend that you keep your heart rate below the anaerobic threshold. Going over this threshold presumably puts too much strain on the body and can trigger the post-exertional sickness. But my heart rate has been so variable that keeping it below 95 bps, my anaerobic threshold, has been an impossibility. My heart rate regularly shoot up to 120, at least according to my Fitbit, when I walk even on the days when my resting heart rate is 55.
So I have not had any useful tool to manage to avoid the post-exertional sickness other than keeping the records and maintaining a regular schedule of activities whenever possible. And it has been difficult to string together a week without getting sick. (Though, this has more to do with my lack of discipline than anything else).
That's what this project has been all about, to figure out a useful tool that can assist CFS patients in pacing their activities and avoid getting sick. And it would be useful enough if the tool can help bring up the activity level to 70 or 80% of threshold. That extra 20-30%p, combined with avoiding the sickness, can make a huge difference in quality of living.
So I got an activity tracker last year and start looking to figure out a way to manage my activities at optimal level. There has been some insightful discoveries. After looking at it for almost a year, however, I'm slowly coming to a conclusion that off-the-shelf trackers may not be accurate enough to be useful for CFS patients. We may need a medical grade monitor with higher resolution and precision. That is especially true for severely ill patients who can end up with post-exertional sickness just by walking from the bedroom to the bathroom. I'll also need something that can discern different ADLs with enough precision. But there are still a few more hypotheses (dozens, actually) that I'd like to test before moving on to Android Wear and beyond.
Unfortunately (or fortunately, I shoud say), it appears that my CFS is suddenly improving and perhaps even recovering. I have accumulated one year's worth data, so I may be able to continue with my analysis for a while. But I won't be able to test the predictions on myself anymore. If any CFS patient out there is willing to participate, I'd be happy to work with you. I may be able to help you with managing activities in the process. A second pair of eyes is always useful when you are trying to pace.
Saturday, July 2, 2016
Fatigue Returns
The familiar fatigue, ache and weakness returned after 3 days of whirlwind activities. I planned to go to MetroPCS store a few blocks away for a new cell phone plan today, but I'm going to give up on it. I'll have to rethink my plan to walk 3 miles tomorrow too. I sure had fun last night though, picking out the color of a new bike and fantasizing biking around the city once again like I used to 8 years ago. Should I get the orange frame to go with Ultegra 22 speed? Hmm... Now I feel exhausted just imagining pedaling.
Even if this wasn't the recovery, it could be at least an improvement. So I'm not giving up the hope, not just yet.
Even if this wasn't the recovery, it could be at least an improvement. So I'm not giving up the hope, not just yet.
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