Relationship between IF and RPE

I’m still new to riding outdoors with power. Today I went out for a ride (yay for daylight and no rain at the same time in weeks!) and at the end my IF for the ride was .9. The ride was 1:20 minutes long, and I calibrated the power meter with my Garmin before starting the ride. It was rather windy, but it wasnt awful and honestly before getting a power meter I would have scored this maybe a 5 or 6 for estimating my TSS in TrainerRoad. For reference I did Bald Knob(.67 IF) on Thursday and it was really easy. Had I been riding that easy outdoors I’d have scored it more like a 3.

Now, I realize that RPE is very variable/individual dependent and what might be a 9 effort on one day might be a 6 on another day. I’m also at the end of SSB1MV recovering, so while I’m certain my FTP has increased some, I dont think its increased enough to make a .9 IF feel like a .5. Santa is bringing me a ramp test for Christmas morning, so I’ll know more then.

I guess my question is: On an “average” day, should RPE and IF match up to feeling about the same?

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I’ve found IF and RPE to be reasonably well correlated, but do get a little disconnected (fo me) on each end.

Longer, low intensity rides feel harder than what IF suggests, and VO2 max stuff fees harder than what IF suggests.

A 0.9 IF should feel hard. Either your FTP is too low, or your Garmin does not have the right FTP loaded in.

Just double checked and Garmin 520 matches TrainerRoad FTP from my last ramp test at the start of SSB 7 weeks ago.

The trouble here is that RPE is duration and intensity dependant whereas IF is only intensity dependant.

If you rode at 0.8 IF for 1 hour and gave that an RPE score of, lets say, 8 (just to keep the numbers easy to work with) and then compared that to a ride at 0.8 IF for 3 hours the RPE would be much harder, maybe 10, even although the IF is the same.

To get the same RPE as the 1 hour ride at 0.8 IF, you would have to reduce the intensity for the longer duration.

I believe this is the way that TR works out a TSS score when you don’t have power.


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