More FTP Questions

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Please bear with me I've ordered the Coggan book but am eager to try and figure out what some of this stuff means while I wait to do more formal testing.

Anyway as far as testing so far I've done a couple all out efforts at 5 minutes with my average power hovering about 320 watts (5.33 w/kg). Last night I did a fairly hilly 10 mile tt with an average power of ~292 watts (25:06). Based on a previous thread (re:ft measuring) is it fair to say that a relatively high 5 min power would indicate a higher anaerobic capacity and therefore the 292 watts would be closer to the ~110% (for example) of ftp as opposed to 105% that's commonly used?

Maybe I'm reading too much into this stuff but I'm trying to soak up as much info as possible.

thanks,
wayne

That's actually quite a low 5 minute power, relative to your 25 minute power. My 5 is usually 120-125% of my 20 minute best.

But since you've got 2 data points, you don't really have to futz with the 105 or 110% stuff, you can actually use the two data points (the critical power method) to project FTP. Comes out to about 288W in your case...although I'm suspicious of a couple things:

1) From your wording, it's a bit unclear whether or not you actually averaged 320W for 5 minutes. Did you review the file?

2) You were perhaps at a different level of motivation for the tests. Pinning on a number for an actual TT often leads to higher numbers than just messing around with a test.

If these numbers are valid, then critical power analysis indicates you have very low anaerobic capacity. a 1M test (and/or a third data point) would help shed light on that.

That's actually quite a low 5 minute power, relative to your 25 minute power. My 5 is usually 120-125% of my 20 minute best.

But since you've got 2 data points, you don't really have to futz with the 105 or 110% stuff, you can actually use the two data points (the critical power method) to project FTP. Comes out to about 288W in your case...although I'm suspicious of a couple things:

1) From your wording, it's a bit unclear whether or not you actually averaged 320W for 5 minutes. Did you review the file?

2) You were perhaps at a different level of motivation for the tests. Pinning on a number for an actual TT often leads to higher numbers than just messing around with a test.

If these numbers are valid, then critical power analysis indicates you have very low anaerobic capacity. a 1M test (and/or a third data point) would help shed light on that.

There's also the fact that he described the 10 mi TT as "very hilly", which means that the average power from it may be an underestimate of what he could really sustain for 25 min (plus 6 s). If that's true, though, then that would make his anaerobic work capacity appear even lower...

Last night I did a fairly hilly 10 mile tt with an average power of ~292 watts (25:06).What was NP for this effort?

That's actually quite a low 5 minute power, relative to your 25 minute power. My 5 is usually 120-125% of my 20 minute best.

But since you've got 2 data points, you don't really have to futz with the 105 or 110% stuff, you can actually use the two data points (the critical power method) to project FTP. Comes out to about 288W in your case...although I'm suspicious of a couple things:

1) From your wording, it's a bit unclear whether or not you actually averaged 320W for 5 minutes. Did you review the file?
Yes this number came from the five minute max efforts as prescribed for the warmup on cyclingpeakssoftware.com by Coggan. Prior to the TT it was 320 watts on the nose but I didn't do the 1 min efforts. On a previous attempt where I ended up not doing the 20 min TT test, my 5 minute average was 317 watts.


2) You were perhaps at a different level of motivation for the tests. Pinning on a number for an actual TT often leads to higher numbers than just messing around with a test.
This was actually a club TT and honestly I avoid TTs like the plague so I don't know if I was particularly motivated for this effort but it did hurt :) Just to be more clear these numbers came after a rest day following a race weekend with a 42 mile RR and a 50 min criterium both on Sunday.

BTW thanks for all the input, training with power is turning out to be quite a revelation for determining my strengths and weaknesses :)

wayne

What was NP for this effort?
I don't have the numbers with me but I'm pretty sure the NP was exactly 300 watts.

wayne

There's also the fact that he described the 10 mi TT as "very hilly", which means that the average power from it may be an underestimate of what he could really sustain for 25 min (plus 6 s). If that's true, though, then that would make his anaerobic work capacity appear even lower...
It certainly wasn't very hilly. Half of the course was a very slight grade, with most of the climbing coming from a couple hills totaling maybe 500 feet of vertical. So hilly is probably an exaggeration...

wayne

I don't have the numbers with me but I'm pretty sure the NP was exactly 300 watts.

wayneIn a hilly TT, your power was probably quite variable. For a duration as long as 25mins and for a course with either significant and frequent grade and/or wind changes, NP is probably a better estimate of your max sustainable power for that duration. Depending on your motivation and residual fatigue, it's possible that your 25min power is greater than your NP (300W), but it's unlikely that it is less than your NP.

It certainly wasn't very hilly. Half of the course was a very slight grade, with most of the climbing coming from a couple hills totaling maybe 500 feet of vertical. So hilly is probably an exaggeration...


And you said "fairly hilly", not "very hilly"...apologies for not quoting you precisely.

Anyway, comparing your normalized power to your average power will provide a direct indicator of how variable your effort was, which in turn will provide an indication of how much your average power might have been impacted.

In a hilly TT, your power was probably quite variable. For a duration as long as 25mins and for a course with either significant and frequent grade and/or wind changes, NP is probably a better estimate of your max sustainable power for that duration. Depending on your motivation and residual fatigue, it's possible that your 25min power is greater than your NP (300W), but it's unlikely that it is less than your NP.
Well a FTP of 300 watts would be great but a little optimistic :) The bigger issue with this course is it's out and back twice. Resulting in three turnarounds with zero power, so maybe a different course would be a better test.


Thanks,
Wayne

Well a FTP of 300 watts would be great but a little optimistic :) The bigger issue with this course is it's out and back twice. Resulting in three turnarounds with zero power, so maybe a different course would be a better test.I didn't say 300W was a good estimate of your FTP (60MP). I said NP was a better estimate (than AP) of your maximum power for the duration of the TT effort (25mins). In my case, my 60MP~.97x25MP. But, that is based on my CP Curve parameters. I don't know your parameters, but if they were similar to mine (relative to AWC vs. FTP), your 60MP would be ~291W (pretty similar to jbvcoaching's estimate IIRC).

I didn't say 300W was a good estimate of your FTP (60MP). I said NP was a better estimate (than AP) of your maximum power for the duration of the TT effort (25mins). In my case, my 60MP~.97x25MP. But, that is based on my CP Curve parameters. I don't know your parameters, but if they were similar to mine (relative to AWC vs. FTP), your 60MP would be ~291W (pretty similar to jbvcoaching's estimate IIRC).

What do you mean by CP curve parameters, especially with respect to AWC vs. FTP? For me, my current peak values are 1054 at 5sec, 596 at 1 min, 405 at 5 min, and 332 at 20 min. I'm 80.5kg. I take this to mean my AWC blows compared to FTP or aerobic capacity. Based on that what percent of 20min power would use to estimate FTP. I've estimated my FTP at 305 based on these numbers.

What do you mean by CP curve parameters, especially with respect to AWC vs. FTP? For me, my current peak values are 1054 at 5sec, 596 at 1 min, 405 at 5 min, and 332 at 20 min. I'm 80.5kg. I take this to mean my AWC blows compared to FTP or aerobic capacity. Based on that what percent of 20min power would use to estimate FTP. I've estimated my FTP at 305 based on these numbers.Well, here's the study I am referring to http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15677008&query_hl=5&itool=pubmed_docsum. But, this link will give you a practical way of estimating your AWC and CP parameters http://www.velo-fit.com/articles/critical-power.pdf. Once you have some valid max duration tests (I use 3, 8 and 30mins), you can estimate your CP curve parameters and estimate MP for any duration. Note that the durations chosen for development of the model parameters are important and can bias the results. I think the generally accepted min/max durations are 3/30 mins.

P.S., FWIW, I ran a quick CP model with your numbers (1, 5, 20min MPs) and got AWC=265, CP=3.9, 60MP=326.

Well, here's the study I am referring to http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15677008&query_hl=5&itool=pubmed_docsum. But, this link will give you a practical way of estimating your AWC and CP parameters http://www.velo-fit.com/articles/critical-power.pdf. Once you have some valid max duration tests (I use 3, 8 and 30mins), you can estimate your CP curve parameters and estimate MP for any duration. Note that the durations chosen for development of the model parameters are important and can bias the results. I think the generally accepted min/max durations are 3/30 mins.

P.S., FWIW, I ran a quick CP model with your numbers (1, 5, 20min MPs) and got AWC=265, CP=3.9, 60MP=326.

Thanks for the links. I think I'll use 326 to define my training levels for my next 4 week block. It won't take long to figure out if its overestimated. 95% of my 20minute peak is 315 which I can do for an hour.

Thanks for the links. I think I'll use 326 to define my training levels for my next 4 week block. It won't take long to figure out if its overestimated. 95% of my 20minute peak is 315 which I can do for an hour.Well, remember that the 326 was derived using 1, 5 & 20 min MPs. The 1min MP, in particular, is quite a bit shorter than recommended and can skew the results. But, as you note, if 326 overstates your FTP it will be quickly revealed when you do interval sets with nominal recovery durations. That's why estimating FTP is a bit of a moot point, because both over- and under-estimations are quickly revealed with routine high-intensity workouts.

I didn't say 300W was a good estimate of your FTP (60MP). I said NP was a better estimate (than AP) of your maximum power for the duration of the TT effort (25mins). In my case, my 60MP~.97x25MP. But, that is based on my CP Curve parameters. I don't know your parameters, but if they were similar to mine (relative to AWC vs. FTP), your 60MP would be ~291W (pretty similar to jbvcoaching's estimate IIRC).
My mistake. One more question... Is there a distinction between a 5MP test vs. peak 5 min power from a ride file. I ask because as I mentioned my 5MP test yielded avg power 317-320 whereas during group rides I've managed 5 min. power 328-330 watts. This variation doesn't appear to effect MP estimates but for the sake of accuracy I'd like to be consistent

Thanks,
Wayne

My mistake. One more question... Is there a distinction between a 5MP test vs. peak 5 min power from a ride file. I ask because as I mentioned my 5MP test yielded avg power 317-320 whereas during group rides I've managed 5 min. power 328-330 watts. This variation doesn't appear to effect MP estimates but for the sake of accuracy I'd like to be consistentI think it really depends on the purpose of the data point. Especially if you use NP, I think group rides and races can often produce MP/duration data points that are greater than we can produce at constant power. So, I would be cautious about using NP for such efforts. But, you should be able to use AP for such efforts. But, again, I come back to the purpose of the data point. If it is for the purpose of setting high-intensity effort targets, it will be self-correcting. If you have overstated the target power for such efforts, you won't be able to complete an effort set with standard recovery durations (e.g., 6x5 @ 120%FTP with 5min recoveries). If the purpose is for a pacing plan for a TT, then the basis of the MP estimate matters a lot. I would base a TT max power estimate on either a constant power effort of a similar duration or my CP curve based on constant power performance tests. I face exactly this problem for a hillclimb TT in mid-September. The ride will be 90-120mins and I plan to use variable power pacing. Knowing my max NP for the course will be crucial to my pacing plan because the middle part of the course is the critical part (steepest grades). If I overestimate my sustainable power, I will blow up in the middle section and lose a lot of time in the last third of the course. If I underestimate my sustainable power, I will not ride the middle section as fast as I could have and I can't make it up in the last section.

My mistake. One more question... Is there a distinction between a 5MP test vs. peak 5 min power from a ride file. I ask because as I mentioned my 5MP test yielded avg power 317-320 whereas during group rides I've managed 5 min. power 328-330 watts. This variation doesn't appear to effect MP estimates but for the sake of accuracy I'd like to be consistent

I think you've found what motivates you here, assuming those group ride numbers are AP, not NP. You avoid time trials, and you do higher 5M power on group rides than solo...

Assuming "cny" stands for Central NY, I know you've got a lot of 5 minute climbs there (I lived in Ithaca for 5 years).

I think you've found what motivates you here, assuming those group ride numbers are AP, not NP. You avoid time trials, and you do higher 5M power on group rides than solo...

Assuming "cny" stands for Central NY, I know you've got a lot of 5 minute climbs there (I lived in Ithaca for 5 years).
Unfortunately I guess I'm kind of a one trick pony. I know I'll do alright on the five minute climbs in CNY (near Utica) I'm just worried how the legs will hold up for Green Mountain.

Thanks all for the advice, the Training w/ Power book just arrived I guess I'd better start reading...:)

wayne

(near Utica)
Heh, born in New Hartford.