POWER

[Rob3rt]

Ah.

I test with the 5 min blowout, followed by 20 minute effort protocol and find it matches quite well to what I do for a 25 mile TT.

 

[VamP]

Odd as it may seem, I have never ridden a 25. But will do a few this year.

 

[Rob3rt]

If you follow Coggan, then he defines FTP as the power for a 25TT, NOT a 60 minute effort. As such once you start racing, there is no need to formally test.

Odd as it may seem, I have never ridden a 25. But will do a few this year.

You should race a few even if you aren't that interested in the distance, IME riding 25's makes you a better rider in 10's Also it should help with your crits and road races.

By the same logic, I should do some 50's, but I simply cba!

 

[Pedrosanchezo]

Ah.

I test with the 5 min blowout, followed by 20 minute effort protocol and find it matches quite well to what I do for a 25 mile TT.

This and the 2 x 20 seem most used methods.

I will be getting a PM soon, i hope.

 

[GrasB]

If you follow Coggan, then he defines FTP as the power for a 25TT, NOT a 60 minute effort. As such once you start racing, there is no need to formally test.

So FTP is anywhere from 41min to 75min maximal effort..

What people seem to be describing is more CP not FTP. At 1 hour CP & FTP should be noticeably different, for me there's 3-4% difference.

 

[VamP]

If you follow Coggan, then he defines FTP as the power for a 25TT, NOT a 60 minute effort. As such once you start racing, there is no need to formally test.



You should race a few even if you aren't that interested in the distance, IME riding 25's makes you a better rider in 10's Also it should help with your crits and road races.

By the same logic, I should do some 50's, but I simply cba!

I am actually more interested in the 25's than the 10's. I rode a hilly 40 mile TT last year, and it was one the best things I did all year. In a gruelling kind of way.

 

[VamP]

So FTP is anywhere from 41min to 75min maximal effort..

What people seem to be describing is more CP not FTP. At 1 hour CP & FTP should be noticeably different, for me there's 3-4% difference.

Does it matter though, if you are always using the same benchmark?

 

[GrasB]

Does it matter though, if you are always using the same benchmark?

CP becomes more an exercise in active recovery, FTP is all about sustained effort. FTP wins anything but radically changing condition TTs

 

[VamP]

I'm puzzled. Every definition I have ever seen gives CP60=FTP. You seem to be assuming a different definition. Can you expand?

 

[GrasB]

A lot of people assume that but it's actually wrong! Critical Power is the amount of power you can average over a given time, FTP is the amount of power you can sustain over a certain time. That is I could do 30 sets of 1min @ 400w & 1min @ 100w to get a CP60 of 250w. However I might only be able to maintain a constant 240w for 60min. That's a very unlikely case but it illustrates the issue.

I my self find I produce the most power over 1 hour by varying my effort level throughout that 60 min session by about 25%. Those lower than FTP intervals allow me to recover enough to put a higher burst of power in for a short period, the result is a few % gain on CP over FTP. However if I do that on a turbo or at the Velo I'll actually be slower over 1h than keeping to my FTP.

Most riders have a higher CP out to about 2 hours than maximal sustained power. Over two hours CP & maximal sustained power will be almost exactly the same.

 

[Pedrosanchezo]

A lot of people assume that but it's actually wrong! Critical Power is the amount of power you can average over a given time, FTP is the amount of power you can sustain over a certain time. That is I could do 30 sets of 1min @ 400w & 1min @ 100w to get a CP60 of 250w. However I might only be able to maintain a constant 240w for 60min. That's a very unlikely case but it illustrates the issue.

I my self find I produce the most power over 1 hour by varying my effort level throughout that 60 min session by about 25%. Those lower than FTP intervals allow me to recover enough to put a higher burst of power in for a short period, the result is a few % gain on CP over FTP. However if I do that on a turbo or at the Velo I'll actually be slower over 1h than keeping to my FTP.

Most riders have a higher CP out to about 2 hours than maximal sustained power. Over two hours CP & maximal sustained power will be almost exactly the same.

Yes but it is just a number! Unless you are comparing to others then it doesn't matter your method. Yours differs to others but the point of FTP is to measure self improvement or decline. If that comes from 2 x 20 mins or 1 x 60 mins then so be it. As long as the test is the same every time then the measurement is accurate. It is merely the measurement of ones condition at the time. Why else use it - in amateur terms?

If one wanted bragging rights then surely we would indulge ourselves in a VAM debate or similar where power and weight are key.

 

[GrasB]

If you're racing then that is what you're trying to do. If you start to measure your CP not your FTP then you're going to start getting weird results on race day compared to your stats. This is less of an issue for those who race on a power meter but most people I know only have power measurement on their turbo.

 

[VamP]

Sure. If you race TTs. Any other type of race will be mostly sub FTP with lots of anaerobic efforts.

I have thought about it since yesterday, and I can see that the way I measure might be contributing to the power gap I have on my TT bike compared to my roadbike.

Although nowhere near as much as the fact that I have hardly ridden my TT bike.

 

[Rob3rt]

After all this talk, I decided to do an FTP test on the turbo for giggles last night! Came out with an estimated FTP of 327W.

Since my last estimate/measurement (332W) was taken from a 25 mile TT on the road (I have actually put out up to 337W in a 25TT but not routinely), this test on the turbo seems to suggest I have improved, taking into account my power on the turbo is always notably lower than the on the road (i.e. much more than 5W lower).

My 5 minute blowout was a turbo PB as well at 417W

 

[VamP]

Sweet.