MPA Not Quite Right?

Yesterday I performed the “Xert Fitness Test - Ramps for Breakthroughs” workout. I was able to get a breakthrough on the first section, but I had trouble with the second section. After the 20-minute “cooldown” and three warmup intervals, I started in on the higher power intervals and hit failure before I even got to the third interval where it is supposed to occur. I stopped being able to turn the pedals at all at the end of the second interval. I mean, I tried really hard. I even waited a bit, did the workout again, skipping to that set, and tried it again while maintaining as high a cadence as I possibly could, thinking that I just hadn’t been spinning fast enough, and I still got shut down. My max power ended up being only 765 W although according to Xert, my MPA was around 1,112W at that point. (My maximum power in many recent workouts tends to be anywhere from 1200-1400W, but those are generally shorter sprints that aren’t on the heels of a couple minutes of minutes of 400+ W output.) Do I have something messed up with my settings/data history? There aren’t any big outliers in my workout history in terms of Maximum Power.

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Hmmm… Looking at your chart you may have tapped into your reserves when you where spinning > 130rpm. This cadence is okay for a few seconds when you’re sprinting but will sap you resources otherwise. You may also have been worn out from the previous max effort and can be affected if you’re not totally fresh going into the test.

Yes, that is a long time to hold that cadence, IMO, but I was also going by (or at least trying to go by) the cadence that was being specified in the workout player (I was using the Garmin workout player). I’m also wondering if maybe something wonky was going on somewhere between the Garmin workout player, my Wahoo Kickr, and my Quarq power meter. Both the Kickr and the Quarq were calibrated prior to the workout, and the first set of breakthrough ramps “felt right” in terms of power output, but man that supposed 452 W interval in the last set of ramps sure felt like waaaay more than 452 W to my legs at the time.