Fatigue episodes biochemistry?

July 21, 2023 8:18 PM

I have ME/CFS-esque (moderate-severe) symptoms. (Long covid; four months in). I've noticed that if I overdo it, it always takes between (2:45-3:15) two hours and forty-five minutes and three hours and fifteen minutes before I can move again. I can set a stopwatch, and it's always in this range. I've collected dozens of data points.

Does anybody have any guesses as to what the biochemistry is, here? I'm guessing something needs to be (re-)synthesized or pumped across a membrane, or both (or I'm not even wrong). If I knew what the molecule was, or it's precursors or co-factors, maybe I could supplement or something. Anyway, what might be the rate-limiting step that has to take about three hours?

(This happens independent of PEM. If I only slightly overdo it, I can move again after the clock elapses. If I majorly overdo it, I can still move again after the clock elapses, and then I get PEM two days later.)

posted by zeek321 to Health & Fitness (8 answers total)

I wonder if this is somehow related to ultradian rhythms? I don't know much about them, except for the general idea that 90 minute-ish chunks of time are physiologically meaningful, which I learned from this recent Metafilter post. That term might help you find actual research though...
posted by unknowncommand at 7:05 AM on July 22, 2023 [2 favorites]

Are you good at telling time, generally? There is the chance that your data is based on your ability to know when two hours and forty-five minutes have passed.

That aside, I don't know. I don't think anyone does. If there might be a study you could join, you might be able to help yourself and others.
posted by Lesser Shrew at 2:59 PM on July 22, 2023

This is fascinating. Do you sleep and/or mentally shut down during these periods when you can't move?

I occasionally have autistic shutdowns (caused by overwhelm of various kinds) which sound a little bit similar, though they can be of varying "depth" (or severity) and the duration seems to depend somewhat on that, but is usually between 1.5 and 4 hours. I usually try to take a nap (setting an alarm for 2 hours later), but very occasionally even after the nap my brain will still be "offline" for 30-90 minutes.

One possibility may be that your brain feels the need to rinse itself out.
posted by heatherlogan at 4:27 PM on July 22, 2023

A different area that might be interesting to investigate is whether there is any similarity to what happens during a migraine. Based on what little I know about migraines, they involve some kind of problem with the tight feedback/control of blood flow and neuronal activity in the brain. There could be a dysautonomia connection there. (The PEM, though, sounds more like an immune-system effect, though there are also brain/immune linkages in both directions.)
posted by heatherlogan at 4:34 PM on July 22, 2023

I don’t know if this is helpful but people with Gulf War illness/syndrome also experience post-exertional malaise. Perhaps looking at that research may be informative.
posted by kat518 at 5:38 PM on July 22, 2023

One of the theories about chronic fatigue syndrome is that there is a dysfunction in cellular energy production within the mitochondria. This is the rationale for people trying to use enzyme co-q10 and thiamine to improve these cellular process.
posted by chiquitita at 5:55 PM on July 22, 2023

Now I'm wondering (with no data whatsoever) whether the 2-day lag in PEM is similar to the lag between stress and a cold-sore outbreak; i.e., the actual "incubation period" of a viral resurgence. Hmm.
posted by heatherlogan at 5:25 AM on July 23, 2023

I had a similar experience with long covid where utter exhaustion, often with chills, set in exactly five hours after I woke up, regardless of when I woke up. It would last about three hours and then I'd be back to myself. The cure for me was LDN (low dose naltrexone). It has been transformative. I do still get a little tired at that time of day but only for 20 minutes or so now unless I've really overdone it the day before.
posted by luckdragon at 5:39 AM on July 23, 2023 [1 favorite]