Has the Relative Effort calculation been drastically changed in the last days?

Hi ​@Davide Luisetti, any chance that your HR max got changed automatically? That would have the impact you're describing, other people are also reporting it here: 

Unfortunately that’s not my case… Max HR in my profile remained the same

The 118 seems to be correct, the 60 is indeed much too low. I see that you use a “Perceived Exertion”, please check that you don’t have enabled the switch “Use instead of heart rate”.

I also think the 60 is completely wrong.

I checked what you said and it's not enabled.

As a double check, I tried to change the perceived exertion and the relative effort doesn't change.

I'm quite running out of ideas and hopefully our community can help :)

You could enable “Use instead of heart rate” temporarily, save the activity and then disable that switch. That leads to recalculating the Relative Effort.

Ok thanks, I’ve just done it for these few past activities, so that my Fitness & Freshness graph has now a decent accuracy. But keep using this method wouldn’t be so much precise overall.

I appreciate your advice and hopefully there can be a definitive solution soon.

Maybe other people with same problem who have already solved it.

Today I switched back to automatic HR zones before my ride and the relative effort was correct.

Weird thing is that my manual HR zones are just slightly lower than automatic ones and by being lower, the relative effort should be even higher (and not drastically lower). I thing I’ll just keep automatic zones until it’s solved.

Strava quietly rescaled Relative Effort a while back.
It used to use the raw TRIMP scale — so heavy training weeks could show numbers in the thousands or even hundreds of thousands (especially if you used HR from long multi-hour rides).

They’ve since normalized it to a much smaller range — roughly 0–150 per activity for most people.

Why?
Because people were constantly asking “Why did my Tuesday commute score 47,000?” and Strava’s answer (“trust us”) wasn’t cutting it.

So they simplified it. The calculation logic (based on HR zones and duration) is the same, but the output scale is compressed and normalized to make it easier to compare effort across workout

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