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Post Exertion Infection

Andrew

Senior Member
Messages
2,513
Location
Los Angeles, USA
I can not help but think some of us suffer from post exertion infection. As if exertion weakens our immune systems and allows a suppressed infection to flourish. I might also think that exertion activates our immune systems for no good reason at all, were it not for the fact that antibiotics help me improve when this happens. And taking no antibiotics allows it to persist. Or maybe it's both.
 

PeterPositive

Senior Member
Messages
1,426
I agree.
Often times exertion causes flu-like symptoms or makes it easier to take a cold etc... If an infection is in progress it usually worsens (especially in the cold season).

There's clearly a link but I have no idea what it is, nor I have ever read anything about possible mechanisms for this to happen.

If anyone has links, I'd be glad to learn more, with time.

cheers
 

msf

Senior Member
Messages
3,650
Well, if it was an infection, that would be a pretty simple explanation for why you feel bad - but some people on this forum do not trust simple explanations.
 

*GG*

senior member
Messages
6,389
Location
Concord, NH
I can not help but think some of us suffer from post exertion infection. As if exertion weakens our immune systems and allows a suppressed infection to flourish.

I might also think that exertion activates our immune systems for no good reason at all, were it not for the fact that antibiotics help me improve when this happens. And taking no antibiotics allows it to persist. Or maybe it's both.

I exert myself quit a bit, I am actually doing aerobic exercise. I don't get as sick feeling as I used to after exercising, still don't get the runners high like when I was healthy. But ever since starting taking LDN and high doses of Vitamin D, both immune modulators I believe. Which is since 2009 for the LDN, and at least that for the Vitamin D.

GG
 

Martial

Senior Member
Messages
1,409
Location
Ventura, CA
I would be careful taking antibiotics without any real structure or protocol. You do not want to deal with drug resistant infections, unless you are taking them continously for the full recommended time prescribed.
 

Hip

Senior Member
Messages
17,824
I have been working on a theory for some while now that the flu-like PEM symptoms which some ME/CFS patients experience after physical exertion are due to an increase in sickness behavior.

Sickness behavior is defined as the set of certain metabolic and behavioral responses that animals including humans mount when they catch an infection. Sickness behavior is precisely what you feel when you catch a nasty bug like the flu. It is not the flu virus itself that is causing all the malaise of of influenza, but rather the body's built-in sickness behavior response to the virus that is making you feel so bad. Sickness behavior is designed to help you best combat the infection.

It is the sickness behavior response that raises your body temperature (instigates a fever), deliberately makes you feel tired so that you conserve energy, and deliberately makes you feel like withdrawing from the world a bit and finding a quiet place to lie down and recover.

Michael VanElzakker hypothesized that many of the symptoms of ME/CFS are actually manifestations of chronic sickness behavior. If this is true, then during PEM, which often involves a worsening of ME/CFS symptoms, this would simply translate to a worsening of the sickness behavior that is constantly driving ME/CFS.


Now it just so happens that one of the triggers of sickness behavior is the cytokine IL-6. The interesting thing about physical exercise is that it introduces a massive amount of IL-6 into the blood, which then stays in the blood for several days, and I think this IL-6 may be the cause of PEM, by its ability to ramp up sickness behavior, which may thereby cause PEM and this flu-like malaise and "viral symptoms".

With this flu-like malaise, it feels like your infections are reactivating and getting worse, but in fact it may just be your body's sickness behavior response that is getting worse, as a result of the IL-6.


It is also possible that some viral reactivation might also occur in PEM, but I have not seen any studies looking at whether this might be the case. So I don't think there is any evidence for viral reactivation during PEM, in spite of the "viral symptoms" that ME/CFS patients observe.

People talk about the "viral symptoms" that can appear in PEM, and people assume that these symptoms are due to their viral infections getting worse during PEM, but in fact it may just be sickness behavior that is transiently worsening during PEM. Sickness behavior after all is the mechanism that produces "viral symptoms".
 
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duncan

Senior Member
Messages
2,240
Yeah, I'm thinking "sickness behavior" is potentially just another back door that could be used by some for blaming the patients for their continued symptoms, even if that is not the intent of the theory.

When I get the flu, or Lyme, or a stomach virus, it is the virus or bacteria that is causing the symptoms which manifest in my body. They trigger my body's response. Period.

Isn't IL-6 implicated in the pathology of depression?

I'm thinking this might be a popular theory with the APA
 
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Hip

Senior Member
Messages
17,824
Yeah, I'm thinking "sickness behavior" is potentially just another back door to blaming the patients for their continued symptoms.

There seems to be a worry among certain ME/CFS patients that anything that even remotely suggests a connection to psychology is all part of a secret conspiracy to portray ME/CFS as psychogenic.

If you if you took the time to understand the concepts behind sickness behavior, you would realize that it is the very opposite of psychogenic.


When I get the flu, or Lyme, or a stomach virus, it is the virus or bacteria that is causing the symptoms which manifest in my body. They trigger my body's response. Period.

That is precisely what happens in sickness behavior, as I explained above. However, because sickness behavior is a built-in mechanism of the body, it can potentially get inadvertently and erroneous switched on, at times when it should not be.
 

duncan

Senior Member
Messages
2,240
Did I mention conspiracy? I hinted at opportunity for APA fans, perhaps.

I must disagree, Hip. You may find it difficult to disentangle symptoms from motivations in this theory. Motivations, last time I checked, were well within the psych domain.
 

Hip

Senior Member
Messages
17,824
Motivations and behavioral response are within the scope of psychology, but many of the symptoms of ME/CFS are indeed psychological. This disease has physical symptoms, but also mental ones.

There is however an important distinction between psychological and psychogenic.
 
Messages
18
Hip's description is entirely biologic so it's unclear where the confusion (and suspicion) comes in (unless the word "behavior" is a trigger for some). It's clear that for some people exercise results in a flu-like response. While I don't think "sickness behavior" is the clearest terminology that could be used to describe this response, the meaning seems clear, that it is a physiological response nonetheless.

If indeed this flu-like response is triggered by a specific cytokine that is generated by exercise, this would seem to be a promising avenue for research and theorizing. Are there currently any CFS theories related to cytokines, and any treatments (theoretical or otherwise) to reduce specific cytokine activity?

***** In re-reading Hip's post, I see that the phrase "sickness behavior" can be interpreted as someone "behaving as-if they are sick", which does not seem to be Hip's intention at all (and could create confusion as to psychological motivation). The term "response" would be a much better alternative to "behavior" in this context.
 
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Hip

Senior Member
Messages
17,824
***** In re-reading Hip's post, I see that the phrase "sickness behavior" can be interpreted as someone "behaving as-if they are sick", which does not seem to be Hip's intention at all (and could create confusion as to psychological motivation). The term "response" would be a much better alternative to "behavior" in this context.

I guess some might inadvertently interpret the phrase "sickness behavior" in that way, as a synonym for malingering; but in fact sickness behavior is just a standard term used in biology and medicine to describe the animal response to infection. It is actually an apt phrase for this purpose, because sickness behavior is not concerned so much with the immune response to infection, but rather to the built-in behavioral response that animals naturally have to infection, and to some metabolic responses, like fever and loss of appetite.

This table compares the characteristics of sickness behavior and the symptoms of ME/CFS. You will notice that there is a phenomenal similarity. Though sickness behavior likely cannot account for all ME/CFS symptoms; but it may well explain the majority of them.

The most important thing to note about sickness behavior is that it is triggered by certain pro-inflammatory cytokines (namely IL-1β, TNF-α and IL-6) that appear during infection.
 
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lansbergen

Senior Member
Messages
2,512
People talk about the "viral symptoms" that can appear in PEM, and people assume that these symptoms are due to their viral infections getting worse during PEM, but in fact it may just be sickness behavior that is transiently worsening during PEM. Sickness behavior after all is the mechanism that produces "viral symptoms".

It is the immune response that usely causes symptoms with a virus infection. Sickness behavior is part of that.
 

Hip

Senior Member
Messages
17,824
It is the immune response that usely causes symptoms with a virus infection. Sickness behavior is part of that.

Yeah they sort of dovetail together. The immune system may be responsible for local symptoms, like for example a congested nose during a cold, chest congestion during a cough, or vomiting and diarrhea during a gastrointestinal infection.

However, when it comes to the general way that you feel when you are sick, with symptoms like fatigue, lethargy, brain fog, low mood, increased pain, these are part of the sickness behavior response, not the immune response. This sickness behavior response is triggered by cytokines from an active immune system, but is distinct from the immune response.

In fact, it is possible to isolate the sickness behavior response from the immune response. The vagus nerve is key to the sickness behavior response: the vagus detects when the immune system is active in the body (which usually indicates an infection is going on). On detection, the vagus nerve then signals to the brain to activate sickness behavior. So this is how the immune response triggers the sickness behavior response.

However, in animals experiments, when the animal's vagus nerve was cut, animals that were abdominally injected with an inflammatory cytokine (IL-1β) normally produced in infections showed all the normal immune responses to fight the infection, but in spite of the fact that they were injected with this inflammatory cytokine, did not display any of the normal malaise and sickness behavior responses that you would expect during an infectious illness. The animals felt fine, yet their body was mounting an inflammatory response.

So this shows that if it were not for the built-in sickness behavior response, animals and humans would feel perfectly good and healthy, even when they had a nasty case of the flu. They would observe all the local flu symptoms like a runny nose, but they would not feel bad at all. They would feel as fit and able as they usually are.
 
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Messages
18
So this shows that if it were not for the built-in sickness behavior response, animals and humans would feel perfectly good and healthy, even when they had a nasty case of the flu. They would observe all the local flu symptoms like a runny nose, but they would not feel bad at all. They would feel as fit and able as they usually are.

So are you implying that the cytokine/inflammatory response (sickness behavior) causes an ACTUAL disruption in energy production, a PERCEIVED disruption in energy production, or NO affect on energy production? (By energy production I guess I am referring to the body's ability to utilize ATP efficiently.)
 

Hip

Senior Member
Messages
17,824
So are you implying that the cytokine/inflammatory response (sickness behavior) causes an ACTUAL disruption in energy production, a PERCEIVED disruption in energy production, or NO affect on energy production? (By energy production I guess I am referring to the body's ability to utilize ATP efficiently.)

That is a good question. I don't know the answer for sure, but as far as I am aware, the sickness behavior response does not down-regulate the body's energy production, but rather induces a mental state in which you feel fatigue. In other words, the fatigue and lethargy that is induced by sickness behavior is a psychological condition imposed on you by your body.

The idea is that this induced feeling of fatigue makes you conserve energy, because you feel too tired to engage in strenuous activities, and this means your body has more energy available to fight the infection. That is the theory of why the body deliberately creates this fatigue. It would not make sense for the body to actually down-regulate energy production, because you need energy to fight the infection.

So the feeling of fatigue you experience in your mind is designed to appropriately regulate your behavior.

The depression that is imposed on you by sickness behavior is I think for similar purposes: if your mood is low, you are more likely to just sit around doing very little, which is what you body wants you to do, so that you can direct your bodily resources to recuperating from the infection.
 

lansbergen

Senior Member
Messages
2,512
So this shows that if it were not for the built-in sickness behavior response, animals and humans would feel perfectly good and healthy, even when they had a nasty case of the flu. They would observe all the local flu symptoms like a runny nose, but they would not feel bad at all. They would feel as fit and able as they usually are.

The vagus nerve is not the only route.
 

Mij

Messages
2,353
@Hip since you've brought up the topic of sickness behaviour I've been reading a little more about it. Since there are similarities and also distinctive differences, I can say I've experienced both (independent of each other) and can identify the difference. I've actually never given it any thought until you brought it up. One thing I can say for sure though is that it is not at all like experiencing PEM.

In the last 2.5 months I have been battling some sort of terrible viral infection, symptoms come and go but it's still persists. I try to get out for my power walks on days I feel "better", but my legs get weak/stiff and I can't get 5 minutes before I have to stop. This to me is not a disruption of ATP or mitochondrial inefficiency, but my bodies mechanism to save energy/adapting to fight the virus. Interesting. I can say it's not at like PEM at all.

Since you don't experience physical PEM (only mental PEM) could it be possible that you don't understand the differences? I mean, just in a physical way?
 
Messages
18
In other words, the fatigue and lethargy that is induced by sickness behavior is a psychological condition imposed on you by your body.

After approximately 20 years of this illness, I can say my symptoms only occur post-exertion. I know I'm fatigued because my resting heart rate is about 20 bpm higher and I can feel my body working harder at rest. While I experienced brain fog and muscle aches consistently for the first 10 years, at this point I can say that fatigue and lethargy are a result of poor energy production and a depletion of energy in every major bodily system. Therefore likely not a "sickness behavior", and IMHO not a psychological condition. At least that's my experience.
 

SOC

Senior Member
Messages
7,849
That is a good question. I don't know the answer for sure, but as far as I am aware, the sickness behavior response does not down-regulate the body's energy production, but rather induces a mental state in which you feel fatigue. In other words, the fatigue and lethargy that is induced by sickness behavior is a psychological condition imposed on you by your body.
And this fits with established research showing failed 2-day CPET tests how? The failed 2-day CPET is evidence of clear physiological abnormality, not a sickness behavior-induced psychological state.

Now it just so happens that one of the triggers of sickness behavior is the cytokine IL-6. The interesting thing about physical exercise is that it introduces a massive amount of IL-6 into the blood, which then stays in the blood for several days, and I think this IL-6 may be the cause of PEM, by its ability to ramp up sickness behavior, which may thereby cause PEM and this flu-like malaise and "viral symptoms".
Neither daughter nor I have, or have every had, abnormal IL-6. We are not alone in that. As far as I know, elevated IL-6 is not a universal finding in ME/CFS.

@Hip since you've brought up the topic of sickness behaviour I've been reading a little more about it. Since there are similarities and also distinctive differences, I can say I've experienced both (independent of each other) and can identify the difference. I've actually never given it any thought until you brought it up. One thing I can say for sure though is that it is not at all like experiencing PEM.
Since you don't experience physical PEM (only mental PEM) could it be possible that you don't understand the differences? I mean, just in a physical way?
I've been wondering the same thing. Most people have experienced sickness behavior. Those of us who have experienced sickness behavior and clear ICC-defined PEM know that the two are definitely not the same. Descriptions of PEM using the word "fatigue" may confuse people who don't experience physical PEM into thinking that the fatigue and lethargy associated with sickness behavior are PEM, but they most definitely are not.

Additionally, many of us do not suffer the psychological symptoms of depression, lack of motivation, and so on associated with sickness behavior as part of our ME/CFS or even just during PEM. That throws another wrench in the theory of sickness behavior = ME/CFS or even sickness behavior = PEM.