# Strava Weighted Avg Power vs Trainerroad Normalized Power?

TR NP was 25 watts higher than Strava’s WAP for the same ride (which had a lot of breaks). Which number should I be using to brag about… err, which is a better representation of the intensity of my ride?

A good general rule in life is to ignore any metric that Strava gives you.

Seriously. Use them for tracking your buddies, the social aspect of their platform, but absolutely ignore any training numbers they have.

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Macaroni in a pot
that’s some Weighted Avg Power, uh

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Assuming that both are calculated using the same math but Strava’s version simply doesn’t use the term NP due to copyright reasons, what does the discrepancy come from?

Not the same thing maths wise which is why they are different. Numbers in general are rather useless comparing/bragging to others due to a bunch of factors.

Different calculations, but the same concept - trying to establish an equivalent steady state wattage. Strava is always significantly lower for me. NP power in TR and on my Garmin always match and is a more common metric, so I typically use NP to compare past efforts.

Based on the wattage I was doing during the ride and the fact that Strava shows I was between 0-24 watts for an hour and a half in ride a bit over two hours (with over an hour sitting around in between), I suspect that TR’s NP is a better representation of how hard the ride actually was while I was riding. I know I didn’t coast nearly that much.

If I remember TR’s NP is based on Coggan’s approach, while Strava’s is based on Phil Skiba’s approach. The way of calculating them is different and therefore the result is different.
Now, which of the two is more closely a steady state metabolic equivalent I can not say for sure.

This

Strava seems to base WAP on elapsed time not moving time, even if you have your computer set to auto pause when you stop. When I ride with no breaks (e.g. a closed road race or crit) then TR, Garmin and Strava are all pretty close. The more stop time there is, the bigger the differences.

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