Road Bike Racing - Threshold Power / pacing - short 8.2 mi TT power data

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For those of you who TT with a powermeter, how do you use it to pace yourself? This morning was the first time I've tried, and I think it caused me to be too conservative. I tried to shoot for 370-380, which I believe to be my threshold range (my max 20 min is 390 on a HCTT a few weeks back). I guess I should have limited to over my threshold, but I'm not at all used to riding in aerobars and it's naturally harder for me to get high power on the flats. I also ruined my time, wasted energy, and got out of my zone by missing a turn and having to backtrack, then accelerate back to speed. For a nearly all flat course (but with significant wind changes), it looks like I also have too many oscillations in my power.
The most confusing thing for me now, looking back at the data, is how high my heart rate was, even though I felt I was throttling myself too much. I started picking it up too late, and from the fact I was able to average 470 in the last minute, I must have had too much left in the tank at the end. From testing a year ago, my heart rate at LT was 179-180 or so (max 201), and this is supported by a drop off in my heart rate histogram there for hard rides. Yet my average heart rate here was 187... and I've seen an avg of 184 for a 2+ hour climbing intensive road race.
I attached a shot of the wko file with a gridline at 385. Anyone care to share insight about my threshold power, high heart rate, etc from this? If this had been a maximal 20 min, Coggan would say to subtract 5%, giving me 355-360, but I don't think that's right for this.
fly:yes/land:no
04-13-07, 02:27 PM
i don't tt or have a powermeter. all i can say is... you are a monster. tough luck about the turn, though.
GuitarWizard
04-13-07, 03:00 PM
I don't know what I'm looking at, but it sure looks impressive.
I wish Saris would get an altimeter integrated with the PowerTap. That would be great.
Lithuania
04-13-07, 03:02 PM
I don't know what I'm looking at, but it sure looks impressive.
I wish Saris would get an altimeter integrated with the PowerTap. That would be great.
I read something recently that said cycling peaks is working on a feature to merge data from a power tap and garmin so if that happens you will have that.
Back to the topic at hand I dont have much to offer but I think your inclination that you should have went harder is probably right since you did have gas left at the end of the effort. I assume the heartrate is going to be off because of nerves over the event it self.
I don't know what I'm looking at, but it sure looks impressive.
I wish Saris would get an altimeter integrated with the PowerTap. That would be great.
They really don't have an excuse not to throw in a barometric pressure altimeter, given the price. But there's probably a total of about 20 feet of elevation change on this course so it wouldn't have been too exciting here... I could ride with my altimeter computer on too, but I'm a little too obsessed with the data as is.
That's some crazy power! What kind of bike do you have and how much do you weigh? With all that power on tap I was expecting higher than 26 mph on a flat course--but I don't know anything about the quality of the road.
--Steve
OC Roadie
04-13-07, 03:57 PM
The road is very smooth, but it was breezy.
Adxm- That's still a very respectable time. I was out there this morning with a lousy 20:29.
KendallF
04-13-07, 04:02 PM
Something's odd here. Did you have a sail attached to your back? :) I have done a few 8-10 mile efforts in training lately, and I put out a LOT less power than you. I weigh 180 at 5'9" with a lot of upper body mass; i.e., I am not the most aero guy out there. With a round tube TT bike and a decent position (i.e., I have a good amount of drop, back fairly flat, etc.) I have been averaging about 25-26 mph for these, at 275 watts or so.
That's the biggest thing that jumps out: assuming this was an out and back course, and looking at the fact that your speed was fairly constant, you should be going a LOT faster for that power.
After saying that, how about your perceived effort? If you were over your FT, were you breathing very hard, was the RPE very high? If not, I'm inclined to say you have a power calibration issue and you left some on the table because you were UNDER FT. This would seem to be contradicted by the heart rate data though, which is why I say something doesn't add up. Your heart rate was weirdly steady, not rising appreciably even when you sprinted after the turn (of course, maybe you were maxed out..).
Jim Bonnet
04-13-07, 06:41 PM
Thats crazy power. You sure you are zero'd out? I just did a 30k TT with higher AVG speed and way less power... Did you have a monster headwind?
Snicklefritz
04-13-07, 06:46 PM
countdown to when Dr.WJO steps in...
Something's odd here. Did you have a sail attached to your back? :) I have done a few 8-10 mile efforts in training lately, and I put out a LOT less power than you. I weigh 180 at 5'9" with a lot of upper body mass; i.e., I am not the most aero guy out there. With a round tube TT bike and a decent position (i.e., I have a good amount of drop, back fairly flat, etc.) I have been averaging about 25-26 mph for these, at 275 watts or so.
That's the biggest thing that jumps out: assuming this was an out and back course, and looking at the fact that your speed was fairly constant, you should be going a LOT faster for that power.
After saying that, how about your perceived effort? If you were over your FT, were you breathing very hard, was the RPE very high? If not, I'm inclined to say you have a power calibration issue and you left some on the table because you were UNDER FT. This would seem to be contradicted by the heart rate data though, which is why I say something doesn't add up. Your heart rate was weirdly steady, not rising appreciably even when you sprinted after the turn (of course, maybe you were maxed out..).
No sail...but no aero helmet, no skinsuit, no aero wheels (my powertap is a 32 spoke open pro), regular road bike with so so aero position, profile design T2 mounted aerobars. My handlebars are definitely much higher than you'd want for a true aero position. Dropped from 180+ to about 166 in the past three months, 5'9.5". It's a loop course, and the winds weren't too favorable today. The power is definitely calibrated...my times climbing match what you'd expect with the power output, torque is 0 when coasting. I wouldn't say RPE was very high; I wasn't nearly as tired at the end as I think I should have been...i.e. puking and coughing up my lungs... though I definitely was working hard. Looks like my heart rate did raise from the effort of accelerating back after I missed my turn, but in doing so I wasn't putting out any effort for a few seconds as I turned, then I had significantly lower output for a little while after as well. I think I should be going faster too, I don't know. But then again sounds to me like it should take more than 275 watts to keep 25-26.
I don't know what I'm looking at, but it sure looks impressive.
I wish Saris would get an altimeter integrated with the PowerTap. That would be great.
Saris and Garmin need to get together. Imagine. A Power-Edge. now that would rock.
-D
KendallF
04-13-07, 09:51 PM
Sounds like the big lesson to take away is that you would be a monster on a TT bike with a good position!
Take a look at this article on Cervelo's site:
http://www.cervelo.com/reviews/aerotest.pdf
45 km/h, he goes from 426 watts to 349 watts by changing from a regular road bike/no aero helmet to a TT bike, better position, aero wheels and helmet. That was Kai Hundertmark who is not a small guy.
Sounds like the big lesson to take away is that you would be a monster on a TT bike with a good position!
Take a look at this article on Cervelo's site:
http://www.cervelo.com/reviews/aerotest.pdf
45 km/h, he goes from 426 watts to 349 watts by changing from a regular road bike/no aero helmet to a TT bike, better position, aero wheels and helmet. That was Kai Hundertmark who is not a small guy.
Well, at least I'd be a monster with a good position on a Cervelo P3 with Zipp 909s. Oh, racing is so pure.
Chucklehead
04-14-07, 12:53 AM
Well, at least I'd be a monster with a good position on a Cervelo P3 with Zipp 909s. Oh, racing is so pure.
did you race the del mar series this year? i've only been back riding for a little over month, so el cajones is going to be my first of the season.
Greg180
04-14-07, 05:21 AM
Saris and Garmin need to get together. Imagine. A Power-Edge. now that would rock.
-D
NO - SRM and Garmin...Now that would Rock!
GuitarWizard
04-14-07, 03:07 PM
Yeah, if you're rich :)
DrWJODonnell
04-15-07, 11:15 PM
To the OP. I am not sure of everything you are asking but pacing looks ok, though the turnaround spike to get up to speed was too long and as such, the subsequent drop in power was necessary to recover. The oscillations are normal so don't worry about them. Your HR can vary from day to day, so don't worry about it being too high. 470 for the last minute does not seem like too much in the tank unless you don't have a very high 1 min power relative to your threshold power.
Overall, impressive showing.
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