← What I found · the finding
Morning heart rate above baseline
Not found The classic Workwell 'RHR + 15' rule
What the guide says A morning resting heart rate more than ~5 bpm above your personal normal means you overdid it and shouldn't push today.
Fires on ~6 of 10 crash lead-ups and ~5–6 of 10 ordinary days. When it fires, a crash follows roughly 1 time in 42.
- Catches
- 62%
- of crash lead-ups it fired on (sensitivity)
- Stays quiet
- 45%
- of ordinary days it correctly stayed quiet (specificity)
- When it fires
- 2.4%
- of the days it fires are followed by a crash (precision)
- Lift
- 1.12×
- × more likely than knowing nothing
These describe how the signal behaves in daily life, framed against how rare crashes are, not whether the pattern is real. That verdict is the badge above; a usable-looking number doesn't make a signal that didn't hold real. Tier C (worth watching at best), and with only 29 crashes the margins are wide.
What showed up in the data
In four years and 29 crashes, my morning resting heart rate did not rise before a crash. On the strict pre-registered test, 0 of the 15 recent crashes showed the expected jump above my personal normal. If anything, my resting heart rate ran slightly lower in the days before a crash, not higher. A relative (z-scored) variant flickered in the early window but didn't survive a clean baseline.
How we tested it
It was pre-registered as H01 before the data was looked at: for every crash, compare my resting heart rate in the days before against my own rolling 90-day normal, and judge it against a bar fixed in advance (most crashes showing a clear rise, holding on a held-out stretch of years). Drafted, audited in a fresh session, locked, then run.
What it means, and what it doesn't
- What it rules out
The most established pacing rule there is (a morning heart rate well above your personal normal means back off) does not flag crashes for my body. It was tested fairly, with the bar set first, and it didn't clear it.
- What it does NOT mean
It doesn't mean the rule is wrong; it's a real, widely recommended pacing rule, and this is a test in my body, not a verdict on the rule for anyone else. It also doesn't mean nothing precedes a crash for me; other signals did better. A negative is about my body, not about you.
- If anything, what it tells you
Two honest possibilities sit behind a clean negative: my heart-rate response may simply be blunted (a known thing in these illnesses), or my crashes may be set off by load a heart rate can't see, cognitive or emotional, not physical. Either way the practical lesson is plain: morning resting heart rate isn't my warning light. It's part of why the search moved to the stress channel.
Go deeper
The short version is above. These go to the method and the raw research.