FTP from ramp test vs. real world IF

I went for an outside ride today, about an hour and a half and it felt like threshold/tempo ish level with some sprints and climbs in there too. The NP is coming out at 196 W, but my FTP from the last ramp test (a few days ago) was 174 W. Giving an IF of 1.13. Would you say this means my ramp test result was inaccurate (fatigue, poor form etc)? If so, how should I proceed?

Is the power meter you’re using the same for both indoor and outdoor?

Normalized Power can be a bit of a tricky metric from an outdoor ride that contains everything but the kitchen sink. What was your average power for the ride compared to the NP?

Yes, if you’re using the same power meter, your ftp in TrainerRoad (intensity scaling) is too low. Increase it 5-10% and see how the workouts feel. It’s not more difficult than that.

Yep it’s the same power meter. Average power is coming out at 95 W on TR, but that seems low to me. Golden Cheetah says the average power was 150 W.

Sounds to me like that’s way too inconsistent of a ride to set an FTP from.

You should clearly distinguish between normalized power and FTP. Normalized power is a weighted average, because the physical toll a ride takes where you spend 1 hour at 75 % FTP vs. one where you work where you spend 30 minutes at 50 % and 30 minutes at 100 % is very different. To account for this, you can take a weighted average where you give the high-effort bits more weight than the low-effort bits. Also, away from a trainer, a velodrome or a time trial, you will never spend 100 % of the time at a specific power level. There are bends, twists and turns, there is a downhill section after the uphill section, where it makes no sense to pedal and every sense to recharge a bit.

As luck would have it, I entered my first race last weekend, and my IF was exactly the same, 1.13. That was because power fluctuated wildly between freewheeling/very little power and giving it the beans. Does that mean TrainerRoad underestimated my FTP by 13 %. Well, it didn’t feel that way yesterday :wink:

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