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Strava FTP Estimate?
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What the hell Strava?


I have been assuming that my FTP is in the 225 range for a while and I have been basically just trying to maintain "fitness". Raced a draft-legal race on Saturday and now Strava thinks my FTP is 300. I'm not seeing any reason to think it's higher than it was last year.

Edit to add Garmin link link: http://connect.garmin.com/activity/457447750

Distance: 20k
AP: 205
NP: 219
Max 20 min: 219

Any ideas?

/kj

http://kjmcawesome.tumblr.com/
Last edited by: kjmcawesome: Mar 10, 14 9:00
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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Not sure what you mean it thinks you have a 300 ftp.

It can be really off but it doesn't update automatically that I know of. Have you gone into settings and put in 225 ftp?
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Re: Strava FTP Estimate? [stodr] [ In reply to ]
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Yep. I have it manually set at 225. I guess it's hard to see in the picture without enlarging, but the graph has an estimated FTP of 300.

/kj

http://kjmcawesome.tumblr.com/
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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kjmcawesome wrote:
Yep. I have it manually set at 225. I guess it's hard to see in the picture without enlarging, but the graph has an estimated FTP of 300.

Probably a software glitch.
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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I would say glitch, probably work itself out. Mine has always been consistent around 95% of my best 20 min
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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Are you using a power meter? If not Strava's FTP estimate are just a wild ass guess that are very influenced by environmental factors.
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Re: Strava FTP Estimate? [JayZ] [ In reply to ]
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In order to even use Strava's best efforts power curve, you must by definition have a power meter to feed it power data. So yes, he does have one.

You might want to take your last 6 weeks of rides and upload them to Golden Cheetah or other software and compare your estimated FTPs. Usually my Strava estimated FTP and Golden Cheetah CP are just about the same.
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Re: Strava FTP Estimate? [paperwind] [ In reply to ]
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Got it. Yeah I haven't done a lot of rides with the PM lately and I just thought there were some strange results. I just thought it was odd that a peak 20 minute power of 219 watts would yield an FTP so much higher. I haven't done many FTP tests and was trusting Strava's extrapolation.

Maybe I just need more data points and to do some longer rides so it can call me out!

/kj

http://kjmcawesome.tumblr.com/
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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Noob question. How do you get Strava estimated your FTP? Do you need the premium account?
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Re: Strava FTP Estimate? [prankster] [ In reply to ]
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Not sure. I DO have the premium account. In the "training" section, there's a link to show your power curve w/ a checkbox to show estimated FTP.

/kj

http://kjmcawesome.tumblr.com/
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Re: Strava FTP Estimate? [kjmcawesome] [ In reply to ]
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Ok, all of you with a power meter and who use strava. I have strava. I don't have a power meter. I will not be buying one for a long time. How close is the estimated power to real power, like from a quarq or srm?

Any and all help greatly appreciated.
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Re: Strava FTP Estimate? [TriathlonKid] [ In reply to ]
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TriathlonKid wrote:
Ok, all of you with a power meter and who use strava. I have strava. I don't have a power meter. I will not be buying one for a long time. How close is the estimated power to real power, like from a quarq or srm?

Any and all help greatly appreciated.

It depends, but if you have a tailwind or headwind it will be way off. Their formula assumes a certain CdA, so it doesn't consider wind at all in their estimate.
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Re: Strava FTP Estimate? [matt_tris] [ In reply to ]
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Alright, the day in question for me there was no detectable wind while I was riding.
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Re: Strava FTP Estimate? [TriathlonKid] [ In reply to ]
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TriathlonKid wrote:
Ok, all of you with a power meter and who use strava. I have strava. I don't have a power meter. I will not be buying one for a long time. How close is the estimated power to real power, like from a quarq or srm?

Any and all help greatly appreciated.

It varies from relatively okay to not even close. Anything on flat roads on a TT bike will be WAY off. Long climbs are relatively close.

I wouldn't put much stock in it except for something like a solo steady state hill climb. If you've got your weights right (bike, body, equipment, etc.). And even that is probably at best 5-10% off.

Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava
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Re: Strava FTP Estimate? [TriathlonKid] [ In reply to ]
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TriathlonKid wrote:
Alright, the day in question for me there was no detectable wind while I was riding.

Then it depends on if your weight entered is correct and your bike setup meets the CdA that Strava assumes. If you drafted all, then all bets are off.

I always looked at the power estimate as a "for fun" stat. There's way too many variables for it to be taken seriously.
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