Originally Posted by
Barry2
Being able to self pace for a 20min FTP test is a tough skill.
Even if indoors under constant load, knowing what number to hit on the power meter requires knowledge of your prior performance and where you expect to be now.
Exactly. My official 20-minute tests were based on what took me to the edge while on Alpe du Zwift & the Innsbruck KOM climbs, as well as structured over/under workouts on Zwift.
I had an idea of what I could hold for 20 minutes, and although I faded slightly before the end I had enough to push for the last minute & hold steady.
My 20-minute power did not vary much.
Also, the number generated by Garmin & Zwift was very close to what the Xert CIQ app gave me, Xert was 2% higher, as it included some of the warm up phase.
The 20-minute number was pretty accurate for a one hour effort as well (over an hour).
I backed that up on a the Mt. Washington Auto Road Bicycle Hillclimb race.
My effort of almost 1.2 hours with a significant portion at over 5,000 feet was at 92% of my FTP.
There is no let up on that climb, it's 7.4 miles at an average of 12%, nothing less than ~8%, nowhere to let off the gas.
I'm sure that if I had tried to go at 100% the whole ride, I would have cracked at the one-hour mark.
I have friends who have done so.
YMMV