the thing I hear most, and believed myself for the first year, is that you crash because you overdid it that day. you had a good tuesday, you did too much, wednesday you’re on the floor. cause and effect, clean story. it’s mostly wrong, and the wrongness is why pacing is so hard.
real PEM runs on a delay. for me it’s 36 to 48 hours, sometimes longer. so the crash on saturday isn’t from friday. it’s from wednesday, a day I’ve already filed under “fine.” by the time the payback lands, the exertion that caused it is two or three days back in the rearview and doesn’t feel connected to anything.
that delay is the whole reason the good-day crash feels so cruel. it isn’t that the good day was a lie. it’s that the good day and the crash are two different events pointing at a trigger you can’t see between them. you’re punished on a schedule that doesn’t match your calendar.
i’m a PT. I taught energy conservation for two decades, and I STILL got this wrong for months because same-day payback is intuitive and delayed payback isn’t. you cannot pace off a signal that hasn’t arrived yet. by the time your body tells you, the window to have done less is long closed.
what actually changed things for me was tracking backward instead of forward. when I crash, I don’t look at yesterday. I look at 2-3 days prior and ask what was different. the log made a pattern I never would’ve caught by feel.
and around month 14 I added a continuous HR monitor and found my resting HR climbs 8-12 bpm in the day or two before a full crash. that’s the closest thing I’ve found to an early warning, because it shows up before the malaise does, in that gap where everything still feels okay. the part I’m still bad at: I know the delay cold and I still crash. knowing the mechanism doesn’t give you a brake, it just tells you what hit you after the fact.
for those of you who’ve been at this a while, how long did it actually take before the delay stopped fooling you? not knowing it intellectually, but actually pacing around it?