Recovery time showing zero after 24hr event

[loopylou72]

I did a 24hr track ultra event on the weekend. Started at zero recovery after taper. Post event my watch says zero hours recovery! I don’t need my watch to tell me to recover ; ) but am curious as to why this would be especially when the app says 'going too hard! I recorded HR on a separate device to save battery but I used a Stryd. And the activity gave me a TSS of over 900. Surely recovery time is recorded without HR? Any ideas? Thanks

[Egika]

@loopylou72 I think the answer is, that the recovery algorithm is based on HR and duration.
If your activity has no HR recorded, one of the input parameters is 0, and thus the calculated value too.

[loopylou72]

@Egika thanks but that makes no sense! Not everyone uses HR and Suunto makes a point of saying they use a TSS which doesn’t need to use HR. So why wouldn’t the recovery use TSS?

[isazi]

@loopylou72 TSS is computed on the app, recovery time uses HR and is a watch only metric. Meaning, the time you need until a hard cardio session.