I had fever (Influenza and body ache, I think) recently and I fast I was hit by weakness/fatigue.
In a matter of hours, I started experiencing the following symptoms (most of which remained for a while even after the fever was over) -
- Weakness/Fatigue - Something simple like lifting my arms for a few seconds caused fatigue as if I had lifted weights. My wrists felt like they would break if I lifted something heavy.
- Brain fog
- Motor control - I walked as if drunk.
All of the above made me wonder -
Exactly what changes happen inside human body that result in this sudden weakness/fatigue?
Why do they continue much later after the fever is gone?
Is the weakness/fatigue an unintentional side effect of fever or is it by design (supposed to help in recovery in some way)?
It is too sudden for muscle atrophy, then what else? Do the muscles stop producing sufficient ATP? Does the body for some reason start accumulating too much lactic acid? Something else?
I'm looking for answers that scientifically explain the root cause.