Crash / PEM tracking
From the app’s English Help & Guide · Reference release 1.0.27
Post-exertional malaise (PEM) is a worsening of symptoms after physical or mental exertion. Crash/PEM tracking helps you log these episodes and see how they relate to your activity levels.
Enabling PEM tracking
Toggle “Crash / PEM Tracking” in More › Tracking. It’s auto-enabled for ME/CFS, Long COVID, Fibromyalgia, and POTS conditions.
Logging a crash
In the entry editor, toggle “Crash / PEM” to mark a crash day. Crash days are automatically treated as flare days regardless of your day rating.
How PEM affects your data
PEM/crash days are always counted as flare days in correlations and patterns. A day rated 4/5 with a PEM crash is still a flare day — this ensures your pattern analysis accounts for crashes even on days that otherwise felt manageable.
Your personal PEM delay
After you log 3 or more crashes and record an earlier exertion date you suspect may be relevant, Tended summarises the time between those records. You’ll see the median interval, range, a distribution chart, and breakdowns by the context you recorded. Find it on the Insights tab under “Post-exertional crashes.”
PEM suggestion prompt
When you create an entry with a low rating or low energy after a busy day, Tended may ask whether you want to record the day as post-exertional. Tapping “Yes” marks the entry as a PEM crash and pre-fills the earlier exertion date for you to check. The prompt records your judgement; it does not diagnose PEM or establish a cause.