That's exactly how I do my CP performance tests, as max duration at a constant power. The only difference is that until now I haven't been able to do them in ergo mode, but rather by manually maintaining a constant power. I'm looking forward to doing these in ergo mode when I get my Velodyne. I actually don't know how to do MP efforts any other way. If I ride a fixed duration at a max power, I'm guessing at the max power. How do I know I couldn't have ridden the duration at 1-2W more?
Thats my point exactly - a max power for duration test is not about estimating a power and riding at that level - think of it like a 100m race, you have a finishing line (in this case a time) and you run it as fast as you can on a given day. Of course you can't know whether you could have ridden 1-2w more, as you say, but presumably with some pacing skills and high motivation, you have given the best you had on the day (for that duration)
Set the power, on the other hand and you will always be limited by that power - if you go over the duration with a power level you have estimated you can sustain for, say 5 mins, then you presumably could have gone harder for 5 mins so now you don't have an accurate figure for that duration (if that is important to you)
Set the power, on the other hand and you will always be limited by that power - if you go over the duration with a power level you have estimated you can sustain for, say 5 mins, then you presumably could have gone harder for 5 mins so now you don't have an accurate figure for that duration (if that is important to you)
But, if one's objective is data points for input to the CP model, the duration is flexible. I never care that my performance test terminates a little before or a little after my target duration. Take the 5min test. I'm fine with a duration of anywhere from 4-6mins and if I have a reasonable idea of my fitness I am unlikely to mis-estimate my 5min max power by more than 1 minute plus or minus. Knowing my 5min max power is sometimes important (actually, all durations can be important in developing a variable power pacing plan), but I can estimate it with the CP curve if I have good parameters (AWC and CP).
But, if one's objective is data points for input to the CP model, the duration is flexible. I never care that my performance test terminates a little before or a little after my target duration. Take the 5min test. I'm fine with a duration of anywhere from 4-6mins and if I have a reasonable idea of my fitness I am unlikely to mis-estimate my 5min max power by more than 1 minute plus or minus. Knowing my 5min max power is sometimes important (actually, all durations can be important in developing a variable power pacing plan), but I can estimate it with the CP curve if I have good parameters (AWC and CP).
Set the power, on the other hand and you will always be limited by that power - if you go over the duration with a power level you have estimated you can sustain for, say 5 mins, then you presumably could have gone harder for 5 mins so now you don't have an accurate figure for that duration (if that is important to you)
One more thing. I find these types of performance tests require some mental adjustment. I think it's a lot different to ride for a certain duration or distance than it is to ride at a constant power until we can't maintain it any longer. It takes a little getting used to mentally.
If you're doing regular say monthly testing then chances are any change is going to be fairly small. For example if I know my last max. duration test on the ergo at 450W was close to 5-min, then I'll choose that power or slightly higher to do the test.
I set the ergo to 450 or 460W and just go as long as I can. The effort is always maximal (on that day). I may reach 4:45, 5:10 or 6:00. It doens't matter exactly as long as I plug the achieved duration into the CP-Monod spreadsheet. Same concept goes for ~20MP test where I may reach 18-22 minutes at my chosen power. As long as I plug in the achieved duration - it's kosher.
So when I say I do 5/20 MP tests, I mean approximately those durations. I never repeat a test to try and hit an exact duration - that would be a waste of time, effort and recovery.
Of course, nothing wrong with hitting your favorite hill or long grade either 🙂
rmur
Is there a copy of the CP/Monod spreadsheet available on the web somewhere? Scott
