# Tech unsavvy question

Did Spanish Needle -1 outside today. 15 sec microbursts are supposed to be at 140% FTP. Scanning the interval listing on TR online it appears that pretty consistently performed at about 150% FTP, with a fair number of intervals above that and a small handful below 140%, mostly due to road-riding stuff. FWIW, did an indoors ramp test Tuesday which showed a 5W improvement at the end of SSBII LV.

So, several questions. First, it looks like NP is quite a bit less than AP for the bursts. I see in the graphs it went high early, then ended up somewhere near or above target. Is that expected?

Second, any easy way to look at the distribution of mircoburst NP? Iâ€™d like to see what the mean and median power was.

Finally, I realize this is an n=1 ride sample. I Would you adjust outdoor FTP based on one ride (although Iâ€™ve had this same feeling about other outside rides â€“ didnâ€™t have the RPE I may have expected). Without being in AT, how might I think about getting the optimum stress in TR workout taken outdoors?

On the â€śwould you adjust outdoor FTP based on one rideâ€ť: The % you can do repeatable VO2 max intervals doesnâ€™t imply your FTP is too high or too low. Especially short duration on / off intervals. So I wouldnâ€™t change your FTP based on this ride, or any VO2 max ride. They arenâ€™t designed to test your FTP power at all.

On â€śFirst, it looks like NP is quite a bit less than AP for the bursts. I see in the graphs it went high early, then ended up somewhere near or above target. Is that expected?â€ť this probably reflects what your power curve for the interval looks like. That is, Iâ€™m betting your power is higher at the start of each â€śburstâ€ť, and decreases throughout the burst.

On your second question, not in TR. You would need to use something like WKO5, Golden Cheetah, etc. Also, the mean power should be the average power

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You canâ€™t use Normalized Power for short efforts. Youâ€™re not supposed to, it doesnâ€™t have real meaning, and how itâ€™s calculated has numerical oddities that means the values in the UI really are meaningless.

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Yeah NP uses a 30 second average power. So for 15 second intervals it wonâ€™t be accurate at all. Most people say you shouldnâ€™t use it for efforts under 15+ min because of the way it is calculated.

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Thanks all for the insight on NP. I thought there was something like that.

Yes, @AlphaDogCycling, the profile for each 15 sec burst was that I started accelerating about 3 seconds before the start of the interval, way overshot, and then eased back during the remainder of the 15 seconds. Most of the time I finished above target, but a few times I dipped below â€“ part of riding on mildly undulating roads.