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# Strava FTP estimate

Road Cycling “It is by riding a bicycle that you learn the contours of a country best, since you have to sweat up the hills and coast down them. Thus you remember them as they actually are, while in a motor car only a high hill impresses you, and you have no such accurate remembrance of country you have driven through as you gain by riding a bicycle.” -- Ernest Hemingway

# Strava FTP estimate

05-10-19, 07:13 PM
#51
redlude97
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Originally Posted by Abe_Froman
So, you're saying strava ftp estimates only work if you already know your ftp through proper testing??
If you dont test and dont ride at maximal testing, then you know nothing. If you do test, then both testing protocol calculations, strava, golden cheetah, xert, and wk04 all provide comparable estimates of ftp. If you ride at maximal intensities at various durations, the strava, gc, xert etc provide estimates of ftp. Which one is most accurate can be debated but you cant with a straight face say all these methods are invalid.
05-10-19, 07:17 PM
#52
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Originally Posted by Abe_Froman
So, you're saying strava ftp estimates only work if you already know your ftp through proper testing??
No. If you only goof-off and fiddle around doing willy-nilly recreational nothings then your measured FTP is not representative of your true potential. You haven't fed it good data and are likely not a candidate that ares about that metric anyway.

Your best efforts are what is used for the calculation. People who care feed it good data by trying hard once in a while. Strava just has better data resolution than the a once in a few months traditional method.
05-10-19, 08:40 PM
#53
LAJ
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Originally Posted by Abe_Froman
So, you're saying strava ftp estimates only work if you already know your ftp through proper testing??
That's exactly it!

Seriously, Abe_Froman is on it. Simply put, you go out and train based on what your FTP is. You don't have time to fart around uploading all kinds of rides for 6 weeks waiting for Strava to tell you what you already know. It's race season, and every single ride I do right now, is based on FTP.
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Originally Posted by rubiksoval
05-10-19, 09:49 PM
#54
base2
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Originally Posted by LAJ
That's exactly it!

Seriously, Abe_Froman is on it. Simply put, you go out and train based on what your FTP is. You don't have time to fart around uploading all kinds of rides for 6 weeks waiting for Strava to tell you what you already know. It's race season, and every single ride I do right now, is based on FTP.
No. You don't have to *wait* 6 weeks. Just go out & hammer down until your eyes bleed. It'll use that ride as the best effort for all data points that ride is the superior wattage. If you weren't as strong as 3 weeks ago, then 3 weeks ago still reigns supreme then drops off as it ages. If you are stronger than 3 weeks ago that current eye-bleeding best effort is your current value.

The algorithm just pulls the highest values available from the last 6 weeks of data to establish your current functional threshold.

Fwiw: There is 2 lines on the graph so you can reference the last 6 weeks to last year, last year to the year before, the year before to the last 6 weeks, etc...each has an estimated FTP based on actual measured values.

Is Summit & a power meter really so hard to understand? It's all based on the Coggins algorithms with actual measued values from a data set. Just like all the other Coggins inspired & sourced tools.

It's only a useful tool if you use it. It's only as good as the data set you feed it.

I, for one, appreciate that 1 hour mountain pass climb or 60 minute out & back being automatically pulled for FTP calculations as it means I don't need to specifically set aside a date/time on a schedule to establish useable metrics.

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05-11-19, 11:45 AM
#55
rubiksoval
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Originally Posted by base2
Is Summit & a power meter really so hard to understand? It's all based on the Coggins algorithms with actual measued values from a data set. Just like all the other Coggins inspired & sourced tools.
.
Except for weighted versus NP. And ATL/CTL/TSB. And, as mentioned and probably the most important, historical FTP.
05-12-19, 07:05 AM
#56
RShantz
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Originally Posted by rubiksoval
Except for weighted versus NP. And ATL/CTL/TSB. And, as mentioned and probably the most important, historical FTP.
This is exactly why I started the original post - the small differences in the above & the fact that my estimated FTP isn't based exactly on the standard calcs. I was just curious if anyone really knew how Strava calculated FTP. I'm not sure if Strava calc weighted power and the ATL etc from the FTP one enters to set zones or from the estimated FTP calculated by Strava.

In the end, it probably doesn't matter since Strava doesn't offer a lot of the power data reporting that others do. Like I said earlier, I think it'd be convenient for Strava to be the one stop shop.
05-12-19, 07:18 AM
#57
RShantz
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Originally Posted by Abe_Froman
If you only ever ride at 60% of your FTP or below, how is Strava coming up with your estimated FTP? Or if you only ever ride on group rides? Or if you very often do short interval training?

I can't possibly imagine how a simulated FTP number serves any purpose other than to be a cute toy to look at online with the purpose of increasing and maintaining subscriptions.
You state that you have a trainer with power. I'm assuming that means you don't have power on your road bike. So you have much less data used for analysis than many others, of course unless all of your riding is on a trainer. Just wanted to make sure you understand that.

So your FTP would have to be calculated based on max effort on the trainer. I assume you know that you can link the trainer data to Strava. Then Strava would have that same data to calculate FTP. With the same data available to Strava and yourself, it's just a difference in the algorithm Strava uses vs the manual calc you perform.

I'm not concerned/curious about the Strava calc to inflate or brag about FTP numbers.
05-12-19, 07:23 AM
#58
RShantz
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Originally Posted by LAJ
That's exactly it!

Seriously, Abe_Froman is on it. Simply put, you go out and train based on what your FTP is. You don't have time to fart around uploading all kinds of rides for 6 weeks waiting for Strava to tell you what you already know. It's race season, and every single ride I do right now, is based on FTP.
05-12-19, 09:05 AM
#59
colnago62
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You guys aren’t the only ones who can’t agree.

The Myth of Functional Threshold Power (FTP) ? MARK TALLON PHD
05-12-19, 09:57 AM
#60
LAJ
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Originally Posted by RShantz
I'm referring to the six week wait that it took for Strava to accurately determine the users FTP. Of course, if you train with power, you have tons of other programs that do a far better job. I don't see the draw to Strava, when there are so many others that do a much better job.
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Originally Posted by rubiksoval
05-13-19, 12:50 PM
#61
redlude97
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Originally Posted by LAJ
I'm referring to the six week wait that it took for Strava to accurately determine the users FTP. Of course, if you train with power, you have tons of other programs that do a far better job. I don't see the draw to Strava, when there are so many others that do a much better job.
If you do 20 min test and upload to strava the estimated FTP will likely be exactly the same as the one you calculate or the one whatever program you decide to use from a single ride, no need for 6 weeks of data. Strava or any other program isn't a replacement for actual training and testing with power
05-13-19, 02:38 PM
#62
RShantz
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Originally Posted by LAJ
I'm referring to the six week wait that it took for Strava to accurately determine the users FTP. Of course, if you train with power, you have tons of other programs that do a far better job. I don't see the draw to Strava, when there are so many others that do a much better job.
That's right, but the draw to Strava for me is for simplification. I'd like to reduce the programs to one. I hope that Strava soon becomes that one-stop shop. They have the data, they just need to upgrade their reporting. I feel certain that's part of their long term goal. I'd assume Zwift has hurt Trainer Road. I'd think Strava will eventually do the same to folks like Training Peaks.
05-13-19, 03:26 PM
#63
redlude97
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Originally Posted by RShantz
That's right, but the draw to Strava for me is for simplification. I'd like to reduce the programs to one. I hope that Strava soon becomes that one-stop shop. They have the data, they just need to upgrade their reporting. I feel certain that's part of their long term goal. I'd assume Zwift has hurt Trainer Road. I'd think Strava will eventually do the same to folks like Training Peaks.
If you want a 1 stop shop why not just use training peaks+wk04?

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