Planning on doing some bike tests coming up, and had a few questions. I will probably be using a CompuTrainer in ERG mode, setting a wattage then going as long as I can within a cadence range or until I stop. Rappstar’s input would be some nice icing. **************This is not the Friel power test
-What rest periods should be in between tests? ( ie. estimated 3min wattage, 6min wattage, etc. as test intervals )
-Anyone have upsides/downsides to using ERG mode vs. going as hard as you can for specified time then taking avg watts?
-What’s the longest time interval that would be useful? (ie. doing 100 watts for 8hours seems useless here. I assume I’d want to keep the wattage just below or above my estimate of critical power?)
-Any other good notes to consider?
I use 5 min and 20 min durations for my tests, and these definitely should be done on separate days. I actually put a full week in between these efforts to ensure they’re true reflections of my fitness.
I don’t have any experience with ERG mode. Do you also have a real power meter on your bike or will your CP numbers be used solely for training?
The critical power model is valid up to about 30 min or so. The goal of the test is to fit your CP and W’ parameters, with the former being an estimate of power output @ “threshold”. Note that CP is a power output that is usually slightly higher than maximal lactate steady state (MLSS) or functional threshold power (FTP) in Allen-Coggan parlance. So in planning threshold-type intervals based on CP you should reduce the power slightly.
A test of 3-5 min and 20 min should suffice although more data points (e.g., 4-6) are better. You probably ought to do the tests on consecutive days - I wouldn’t wait a week in between because presumably you’ll do some training in between that could cause variability in your test result. If you are worried about fatigue, do the 5 min test on the first day and the 20 min test on the second day, however I think it matters little which one you did first (if you want to be statistically rigorous, you’d randomize the order of the tests…).
Doing the test in ERG mode is more “valid” because the model assumes constant power output and the lab tests are usually done that way. However, doing the tests for specific durations is mentally easier (I find) because you assume a “time trial” type of mentality and you know when the end will come. As long as you keep the power output reasonably constant it should be valid.
So far, I can’t say I have seen any difference between time-to-exhaustion “burn-out” tests versus the (more frequently used) field test where the athlete makes an attempt at the best power for a given duration. I will say that the erg-mode solution has turned out to be more popular with athletes, however.