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Jul
16
comment Why are so many technical aspects of cycling so subjective?
There is testing but mostly it's not widely known. For your particular example, see here and here.
Jul
10
comment Swain Power-HR relation
Exactly, though you'll want to exhaust your anaerobic capacity or else you'll overestimate VO2Max. That's why VO2Max tests are usually done with a ramped protocol, and the estimates are done off the final step before failure. In your example, you don't want to use the average of 97kJ for 5 minutes, instead you might want to use the max power over the last minute of a ramped protocol (or another similar protocol where you've exhausted the anaerobic component).
Jul
10
comment Swain Power-HR relation
Ah, okay. The issue is that even if you have HR, you don't have stroke volume which is what you need to get cardiac output. However, if you know metabolic efficiency (net or delta or work efficiency are better than gross efficiency, but sometimes all you have is gross efficiency) you can go from work to get L of O2 consumed, so if you have total mass you can estimate VO2Max. So you don't really need HR -- Swain was using that because he didn't have power, but you do. So do a VO2Max-level power effort and convert directly to estimate VO2Max.
Jul
10
comment Swain Power-HR relation
Can you clarify your question? The Swain model is used to estimate power when you know heart rate, VO2Max, and metabolic efficiency. You appear to have power and HR. Are you trying to go backwards to estimate VO2Max, or metabolic efficiency, or something else?
Jul
3
comment Is there a standard equivalent for effort between distance and elevation?
It's complicated but not terribly so if you know power and speed. That's the basis for the "virtual elevation" approach for estimating cycling drag -- it converts effort (in terms of power and speed) into elevation gain.
Jul
3
comment Is there a standard equivalent for effort between distance and elevation?
Sure there's a way to convert % climb into level miles. All you need to know are a handful of things: your total all-up mass (including you, your bike, and all your equipment), your coefficient of rolling resistance, your coefficient of aerodynamic drag, the wind speed, and your ground speed.
Jul
3
comment Is there a standard equivalent for effort between distance and elevation?
@DanielRHicks If you use a power meter you can estimate "fatigue profiles" that show how power decreases with duration of effort. People who have done so have shown individual consistency under wide (but not extreme) ranges of pedal force and pedal speed conditions. That is, your fatigue profile may differ from mine, and each can change with fitness and training, but otherwise, yes, there is some science to calculating fatigue and recovery rates.
Jul
2
comment Is there a standard equivalent for effort between distance and elevation?
A third option is to track "session RPE" using the 10-point (or 20-point) Borg scale, which doesn't require any hardware investment at all -- and, once you know how to use it and get some experience, is roughly about as accurate as looking at average heart rate.
Jun
23
answered Knee position while on the aero bar
Jun
21
comment Knee position while on the aero bar
It's hard to tell from these photos so take these as comments and questions rather than an answer -- but it seems like that frame may be a bit big for you. Putting aero bars on a road bike isn't ideal -- if you're doing draft-legal you may want to investigate ITU-legal mini-aero bars. Where is the tip of the saddle in comparison to the BB? I'm not a big fan of KOPS or related fitting systems but if you are, then when you drop a plumb line the bike has to be horizontal, and it appears that your bike is being held in the rear on a trainer but the front wheel is on the floor.
Jun
10
comment Why exactly did Boardman manage a further distance than Wiggins?
It's actually not that uncomfortable -- I've experimented with it. That said, it's definitely harder to control the bike so I wouldn't recommend it unless you were on a straight flat road or a velodrome. Alone.
Jun
4
awarded  Good Answer
May
21
comment What is a power meter and why do I need one?
@ChrisCleeland I sort of disagree. I've never been much of an athlete on a bike and a power meter has helped me quite a bit. I got one before I had a TT bike, and this answer, while good in general, mostly addresses the idea that a power meter is only good for training FTP. Power meters can also be used for other things than training FTP -- in fact, training is one of the least demanding things one can do with a power meter.
May
6
revised what power did alex dowsett put out during his hour record?
added 404 characters in body
May
5
comment what power did alex dowsett put out during his hour record?
The rider is allowed to receive very limited information, according to UCI rules: pace, distance covered, or time. If the velodrome is quiet you can shout out lap times but generally for record attempts you use a chalkboard -- though of course more recently teams have been using iPads or other tablets. You don't want to give the rider too much distracting information.
May
5
comment what power did alex dowsett put out during his hour record?
A power meter was mounted on the bicycle but according to UCI rules no visible display is allowed so the data are either for review post-ride or can be transmitted to a track side computer for real-time analysis.
May
5
answered what power did alex dowsett put out during his hour record?
Apr
5
comment How many miles of riding require the same effort as one mile of running?
@StephenTouset, I've done a similar thing for short duathlons, where you have a bike leg in-between two run legs. Here's an example of the splits: anonymous.coward.free.fr/wattage/duath-splits.png
Jan
9
comment How can we calculate the efficiency of the Siva Cycle Atom generator?
Crr scales exactly like slope, so an increase in slope of 0.3% is exactly like saying the Crr increases by .003. Regular road tires (not knobbies) typically have a Crr in the range of perhaps .004 to .008 on smooth roads, so using the Siva would feel like switching from low rolling resistance racing tires to Continental Gatorskins (or from Gatorskins to heavy-duty belted hybrid tires).
Jan
6
awarded  Good Answer