Just asking because my last sprint I did 31min for 20k and yesterday I went to try a computrainer with a friend of mine who is usually slower.
I could barely hold 200watts and was sweating buckets. He was doing 300 watts and leaving me far behind.
My hope is that the two were not calibrated correctly but which was more accurate?
For references I’m 155lbs and my friend is about 200.
I picked up an indoor trainer (angry badger) and my speeds/watts have been horrible compared to what most ST’ers do. I don’t have a power meter on my bike (just the cheap kurt kinetic power meter and the spreadsheet someone made for speed vs watts on the trainer), but my average speed outdoor is usually 1.5-2+ mph easily for 30 minute rides (on a moderate course…some tougher hills). I’ve been complaining because my rides on the trainer just seem pathetic number wise, but I feel like I’m getting a good workout. Just gonna keep hitting the trainer till the weather gets better.
Indoor training is tough…no motivation, no other riders. Competition drives peak performance, such as Phelps paying his top competitors to train with him in Baltimore.
Just asking because my last sprint I did 31min for 20k and yesterday I went to try a computrainer with a friend of mine who is usually slower.
I could barely hold 200watts and was sweating buckets. He was doing 300 watts and leaving me far behind.
My hope is that the two were not calibrated correctly but which was more accurate?
For references I’m 155lbs and my friend is about 200.
It could have been loads of things.
-did you recheck the calibration a few minutes in and half way through? Normally if you have the trainer tire you only need to do it the first 5 minutes that tire is amazing it wont change.
Now as far as your individual time compared to you race time. Don’t compare them. The computrainer will always be slower. Hills are always harder and declines you never make up the speed you do on a regular course.
If you want a real comparison get a powermeter on your bike ride with them both at the same time and see how close they are. My srm and computrainer were within like 5 watts. Then go outside and compare the two wattage wise. That will give you a better inclination then the speed.
Grant
If the 20K were dead flat and your CdA was in the ballpark of maybe 0.22, yeah, it’s possible. However, that you’re asking this question makes me think your CdA ain’t 0.22.
indoor watts are often lower than outdoor watts due to ventilation (cooling), intertia, motivation, etc… I wouldn’t worry too much about it. Ride your ass off indoors today and the results will show come spring.
This is a fun page to play with to see what sort of power is needed to achieve a given speed: http://www.analyticcycling.com/ForcesPower_Page.html
Looks like you can get those speeds with 200w but you have to be fairly aero.
As for the Computrainer, I have found that once calibrated after about 10 mins of riding the wattage values are very close to what my PowerTap gives when averaged over time…within a few watts over anything longer than 30 mins for instance. But the Computrainer won’t credit you with the same speed as you will achieve in the real world for a given wattage, especially if you’re smaller, or if the course is hilly.
31 is definitely possible on 200 watts with proper equipment. On a road bike with non-aero wheels, non aero helmet, etc, no way.
Chris
Another way to look at this: 31 minutes for 20k at 200 watts would translate out to a 4:39 IM bike leg at those watts. No way.
Another way to look at this: 31 minutes for 20k at 200 watts would translate out to a 4:39 IM bike leg at those watts. No way.
yes, but you can theoretically run a much more aggressive/aero setup for 31 mins than 4+ hrs. Right?
at his weight, i am guessing not. the postion wont make that huge of a diff.
such as Phelps paying his top competitors to train with him in Baltimore.
Wait a minute, what!?!
Do tell. And please, post proof. Don’t give me some crap like “I heard it from someone in the know”. I want factual information.
Thanks!
welllllll I heard it from someone with a PhD if that counts for anything?
I’d say 200 watts outside is a little low. But 200 inside and doing a sprint tri at 31 mins is possible. I’d say 200 inside is a good 215 outside which would make it close if he has a very aero position.
I’ve done 24.1 for a 40k on 229 watts. So its feasible. But it would have to be a flat course because a hill course would shoot those numbers up.
Grant
Sounds a little on the low side (wattage) to me. I’m 170-175lb and recall doing 4x20k tt’s in a university laboratory (scientific SRM) at 320 watts +/- 4 watts ranging in time from 30:05 to 30:30. I don’t consider myself super aero but I also don’t ride sitting up!
Outside I ride a P2C with OEM wheels and normal helmet. Aero but not crazy aero. I’m starting tri-specific spinning classes on thursday on new bikes that have power meters so I’ll compare to that too.
Thanks for the comments. Right now I’m thinking that my computrainer was set a little too pessimistic.
Kurt Kinetic makes a couple assumptions when they built out the power function on their trainer. They assume that you are 165lbs, that your bike is 23 lbs, and that you are going up a 1% incline (which although it doesn’t sound like much, is much different than hammering on a flat road), at sea level, on rough asphault. All that is written here:
http://www.kurtkinetic.com/powercurve.php
The more you deviate from these assumptions, the larger your speed difference will be. The wattages are supposed to be approximately correct though (I have no evidence to prove this), so you can adjust the assumptions around on analytic cycling (if you beileve they are an accurate portrayal of real world situations) to figure out approximately where you would be as variables adjust.
honestly if you didn’t recalibrate it at least a couple times throughout the ride, if you are using a normal tire, the wattage could be all over the place.
Grant
Was the distance in the sprint as advertised? If you rode 31 min on an accurate 20K course, you were probably in the top 5% unless it was a downhill course.
I’ve done “20K” bike legs in sprints that were up to a full mile short. That would make a huge difference in your actual mph speed. ~24mph vs ~22mph.
Was the distance in the sprint as advertised? If you rode 31 min on an accurate 20K course, you were probably in the top 5% unless it was a downhill course.
I’ve done “20K” bike legs in sprints that were up to a full mile short. That would make a huge difference in your actual mph speed. ~24mph vs ~22mph.
It was a Triathlon Montreal on the F1 circuit. Almost dead flat and I did finish 5th in the 30-34M despite a horrible swim. It’s faster than what I do when training by myself but then again the adrenaline helps a lot.