Quarq Pre-ride Zeroing
So I am new to the power world and did my first FTP test. I thought I did everything right, then at minute 38 I relized I did not Zero my Quarq. Ouch! It sucks. My NP for the test ended up being 233. My questions are:
1) What is pre-ride zeroing?
2) What is the best way to zero? I have a Garmin 800 if it matters.
3) Are my test results valid?
4) Should I train with this FTp, or re-test?
Any and all adivce/opinions are appreciated.
Thanks,
Gene
0
Comments
(1) Zeroeing the quarq establishes a baseline for the unit, which is impacted by termperature and humidity. In other words, if you zero the unit and then the temperature drops 30 degrees the power readings will not be accurate. In a post I wrote some time ago there is an example of the difference in calibration value and what kind of wattage impact it has. I can't remember the exact numbers but the bottom line is that you should zero the unit beofre you ride and then mid-ride every so often using the "backpedal method".
(2) I don't know how the 800 works in this regard. On the Edge 500 you go to settinggs-->bike-->power-->calibrate.
(3) If I had to guess, I suspect the results are probably fine. It mostly depends on the difference in temperature between your test and when the unit was last calibrated. If the conditions were roughly the same then you can assume you test is valid. If you know for a fact they were wildly different (e.g. zeroed then rode outdoors in mid-30s temp then did the test indoors) then that's a different story.
(4) I'd train with the FTP and if you simply can't ever hit the intervlas then thatd be a good indication that your FTP was not measured correctly. Same thing if you end up with IF 1.05 for all of them. But if you feel like "holy crap I don't think I can hold this for 10'" but then you manage to do it 4 out of 5 times, you're probably in the right spot.
Others may have different input on this...
cheers
Matt