Best way to run a one-time Xert fitness test for a friend?

Tomorrow a friend of mine is coming over to do a fitness test on my indoor trainer. We regularly ride together, and he’d like to know his fitness signature. I’m wondering what’s the best way to approach this.

Here’s my idea so far: I know that on flat terrain he rides about as fast as I do at the same perceived effort. But he’s much lighter (about 50 kg less) and narrower, so his rolling and air resistance should be quite a bit lower. So, as a rough guess, I estimate his TP at about 80% of mine — around 200 W.

My plan: I take the Xert Breakthrough Workout Version 2, adjust it for a fitness signature with 200 TP (and proportionally lower HIE and PP), then export it to Zwift. He’ll ride it, and in the final interval I’ll switch to slope mode and let him go all-out until he’s fully exhausted.

The workout will then get uploaded from Zwift into my Xert account. Afterwards, the question is how to best analyze it. I see two possible ways:

  1. Flag all my own recent workouts so that the new signature calculated from this test becomes his values.

  2. Manually tweak the PP, HIE, and TP values below the workout until it’s just barely “doable” analytically without going over MPA. But the problem here is that there are two free variables, so there could be multiple possible combinations — though I guess Xert faces the same issue when doing its automatic analysis.

Do you have any better suggestions for a one-off fitness test and analysis with Xert? Different method? Different workout?

Maybe he’ll start his own Xert account later on (even though he doesn’t have any power meter hardware yet).

Thanks for your ideas!

I wouldn’t mess with my account that way.
Have your ride buddy create their own Xert account or create a trial account for them.
Login to EBC using that account for the fitness test. You can plug in some estimated signature values under Profile Settings. Use low values so he can prove them wrong during the test.
Ride the entire Fitness Test workout in Slope mode exceeding target watts and durations (if able), especially on any intervals designed to drive you to a failure point. For sprint efforts try to hold max watts for at least 5-7 secs.
Only Version 3 is designed to be ridden in AUTO mode but that assumes your signature is already dialed in.
See: From old trainer to smart trainer. Set FTP - #5 by ridgerider2

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