FT measuring

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Is FT just your avg watts in a one hour effort? I want to compare myself in the "what is your FT?" thread. Just wondering how you are all measuring your efforts.

Is FT just your avg watts in a one hour effort? I want to compare myself in the "what is your FT?" thread. Just wondering how you are all measuring your efforts.
The best result is obtained from a race - either a 25mile/40km TT, or a bunch race over a similar distance, as this is likely to give a figure closer to you ability, as opposed to doing a test by yourself for 1 hour.
It can be estimated from a 20 minute test also, where 92-95% of the 20 minute power is used as the FTP. Some folk are happy to use 95%, but I have tested on several occasions, and my figure is nearly always 92%FTP.

The best result is obtained from a race - either a 25mile/40km TT, or a bunch race over a similar distance, as this is likely to give a figure closer to you ability, as opposed to doing a test by yourself for 1 hour.
It can be estimated from a 20 minute test also, where 92-95% of the 20 minute power is used as the FTP. Some folk are happy to use 95%, but I have tested on several occasions, and my figure is nearly always 92%FTP.
Thanks a lot.

Forgive me if this is common knowledge as I'm new to power training (new powertap sl this week). For the purpose of my initial FTP test I'll probably do a 20 min tt, but for estimating FTP, is it better to initially under or over estimate your threshold when putting together a training plan? While the discrepancy is fairly small (<10 watts) is it important to determine where your FTP falls in relation to a 20 min TT (92%-95%)?

Also how much insight can I expect to get about my FTP from a 50+ mile road race or would it be better to just concentrate on the TT test?

Thanks,
Wayne


The best result is obtained from a race - either a 25mile/40km TT, or a bunch race over a similar distance, as this is likely to give a figure closer to you ability, as opposed to doing a test by yourself for 1 hour.
It can be estimated from a 20 minute test also, where 92-95% of the 20 minute power is used as the FTP. Some folk are happy to use 95%, but I have tested on several occasions, and my figure is nearly always 92%FTP.

Forgive me if this is common knowledge as I'm new to power training (new powertap sl this week). For the purpose of my initial FTP test I'll probably do a 20 min tt, but for estimating FTP, is it better to initially under or over estimate your threshold when putting together a training plan? While the discrepancy is fairly small (<10 watts) is it important to determine where your FTP falls in relation to a 20 min TT (92%-95%)?I think people stress out over micromeasuring their FTP too much, especially when the PM is new. There's no "physical reality" to FTP: it's not like measuring the circumference of the earth. It changes so much day to day due to training state, fatigue, etc., that it's always a blurry target. Anything within 10 W is close enough that the training levels all do what they're supposed to do; even if you wildly misestimated, you'd notice soon enough that, e.g., it's impossible or way too easy to complete a L4 workout.

Forgive me if this is common knowledge as I'm new to power training (new powertap sl this week). For the purpose of my initial FTP test I'll probably do a 20 min tt, but for estimating FTP, is it better to initially under or over estimate your threshold when putting together a training plan? While the discrepancy is fairly small (<10 watts) is it important to determine where your FTP falls in relation to a 20 min TT (92%-95%)?

Also how much insight can I expect to get about my FTP from a 50+ mile road race or would it be better to just concentrate on the TT test?

Thanks,
Wayne

92 vs. 95% is not that important, especially when one takes into consideration the margin of error for PM's. As for FTP from a 50mi RR, it'd be pretty tough to get your FTP unless you were off the front solo for an hour, and even then it would vary wildly depending on which hour you were off the front. ;)

Thanks for all the input guys. I wouldn't expect to get a good estimate of my FTP from a race but from my limited reading multiple tests and analysis of your power numbers can give you a more accurate estimate of your FTP. So assuming early in the race I'm on a 20 min solo break pushing 300 watts but maybe on my 20 min TT I'm only pushing 260 watts, can I assume my FTP would fall closer to 285 (95% of 300) or 250? My concern is that while racing I seem to be able to manage much higher level of efforts than during training so rather than doing a 20 min TT effort every week to gauge my FTP, how can I use race power information to adjust my test information? Of course, if it doesn't help just tell me to stop being a wanker and work harder in training :D

Thanks,
Wayne

So assuming early in the race I'm on a 20 min solo break pushing 300 watts but maybe on my 20 min TT I'm only pushing 260 watts, can I assume my FTP would fall closer to 285 (95% of 300) or 250?
Wayne
It would be closer to 285.

If you use cyclingpeaks software, you can also look at normalized power from hard ~1hr races as an indication of changes in FT.

Many people use 95% of their max 20min power to estimate FTP and I think that this methodology results in overestimation of FTP more often than underestimation. I am in AndROOb's camp here because my 60MP is closer to 92% of my 20MP. But, if the purpose of estimating FTP from a 20min test is to set interval power targets, the error is quickly revealed. You won't be able to do 2x20s @ 100%FTP with a short (e.g., 5min) recovery duration if you have significantly overestimated FTP. And, you won't be able to complete a set of VO2MAX efforts (e.g., 6x5 @ 120%FTP) with an equal duration recovery. The more serious consequence of overestimating FTP is when you want to ride a 60min effort at max power (e.g., 40K TT). Then, an overestimation of your 60MP will cost you time because you will go out too hard and will be forced to drop power in the 2nd half. An alternative to all this is to use the Critical Power Model and do three max power tests (I use 3, 8 and 30mins). Then, you get a pretty good estimation of 60MP or any other duration you want from ~1min to ~2hrs.

What's the difference between FTP and Anaerobic Threshold Power? I did my testing in a lab and the value given was based off of ventilitory measures and stuff.

What's the difference between FTP and Anaerobic Threshold Power? I did my testing in a lab and the value given was based off of ventilitory measures and stuff.I think they are interchangeable terms as commonly used.

What's the difference between FTP and Anaerobic Threshold Power? I did my testing in a lab and the value given was based off of ventilitory measures and stuff.

Functional threshold power is just that: the power "threshold" below which you can continue for a long time without fatiguing, but above which fatigue occurs much more rapidly. Functional threshold power is therefore essentially the same as critical power, the power at maximal lactate steady state, etc.

Anaerobic threshold, OTOH, is a misnomer for what is more properly termed ventilatory threshold, which is essentially the exercise intensity at which you begin to hyperventilate with respect to CO2 production. In normal, healthy individuals, "anaerobic" threshold correlates with, e.g., lactate threshold, but depending on how each is specifically defined, may be lower or higher.

Bottom line: I wouldn't recommend substituting lab-based measurements of "anaerobic" threshold for functional threshold power unless you know what you're doing...

Functional threshold power is just that: the power "threshold" below which you can continue for a long time without fatiguing, but above which fatigue occurs much more rapidly. Functional threshold power is therefore essentially the same as critical power, the power at maximal lactate steady state, etc.

Anaerobic threshold, OTOH, is a misnomer for what is more properly termed ventilatory threshold, which is essentially the exercise intensity at which you begin to hyperventilate with respect to CO2 production. In normal, healthy individuals, "anaerobic" threshold correlates with, e.g., lactate threshold, but depending on how each is specifically defined, may be lower or higher.

Bottom line: I wouldn't recommend substituting lab-based measurements of "anaerobic" threshold for functional threshold power unless you knowing what you're doing...
Ok cool thanks.
One more question, I forget what the difference between zone 5 and L5 training is....Zone 5a in Friel's book is LTHR, but L5 is power based, and what is the duration or value?

Ok cool thanks.
One more question, I forget what the difference between zone 5 and L5 training is....Zone 5a in Friel's book is LTHR, but L5 is power based, and what is the duration or value?

In my schema, level 5 (a.k.a. "VO2max") corresponds to an average power of 106-120% of functional threshold power - see http://www.cyclingpeakssoftware.com/power411/levels.asp for more details.

I tested my treshold power by doing the 20 minutes and taking 95 % of that

It was only 1 week ago :
I managed to hold 303 watts => 288 watts was going to be my starting
magic number

Yesterday I did a 1 hour climb and believe it or not , I averaged exactly 288 watts over the hour and my best 20 minutes again were 303

So : 20 minutes - 5% works for me

I tested my treshold power by doing the 20 minutes and taking 95 % of that

It was only 1 week ago :
I managed to hold 303 watts => 288 watts was going to be my starting
magic number

Yesterday I did a 1 hour climb and believe it or not , I averaged exactly 288 watts over the hour and my best 20 minutes again were 303

So : 20 minutes - 5% works for meAnd it works for many. But, not all. It's a function of the shape of your power duration curve, mainly a function of your AWC relative to FTP.

Of course, if it doesn't help just tell me to stop being a wanker and work harder in training :D


Stop being a wanker and train harder.....Sorry, i couldn't resist. :rolleyes:

I tested my treshold power by doing the 20 minutes and taking 95 % of that

It was only 1 week ago :
I managed to hold 303 watts => 288 watts was going to be my starting
magic number

Yesterday I did a 1 hour climb and believe it or not , I averaged exactly 288 watts over the hour and my best 20 minutes again were 303

So : 20 minutes - 5% works for me

Actually, it sounds as if in your case 0.95 x 20 min power slightly underestimates your functional threshold power. Think about it: you were able to average 288 W during a 1 h climb during which you rode for 20 min at above your functional threshold power...in fact, at the highest power you could sustain for that duration. Presumably, then, you would be able to average >288 W for 1 h if you paced yourself a bit more evenly (although not necessarily by much).

In any case, I'd just call it 290 W, and stick w/ that value until you've got evidence that it's wrong...

Stop being a wanker and train harder.....Sorry, i couldn't resist. :rolleyes:
Thanks, now I can stop screwing around and just go out and do a FT test :D

wayne

Thanks, now I can stop screwing around and just go out and do a FT test :D

wayneOr do three MP tests at shorter durations and use the CP curve. Then, you get not only a good estimate of 60MP but any other duration you want.:D