Anaerobic intervals decreasing FTP?

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by st0tan

I've read conflicting information regarding the effect of primarily anaerobic intervals (ex. 1 minute sprint w/ 5 minutes recovery) on FTP. Some sources say this type of anaerobic work will decrease aerobic power due to its emphasis on anaerobic energy systems while others say the opposite. Any ides which stance is correct?

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by jlok

open a Xert free trial account, sync your year round data to, see how your interval affects TP according to their algorithm. Or pay up and use WKO4+ and see the mFTP.
Litespeed T1sl Disc / BMC TM02 < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

by Weenie

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by Ghost234

If you are solely doing this type of workout, don't expect an increase in FTP or at least not a significant one. It is not that anaerobic efferts reduce aerobic power, it is simply due to specificity. With that level of rest you are going full gas on 1 minute power. That won't likely get you up to vo2 max.

If you were to reduce those rest intervals, or increase the duration you would likely see a larger effect on FTP. One workout I might suggest is 3 efforts of 5x90 seconds ON, 60 seconds off. 5 minutes between efforts. To progress you can (1) increase the power, (2) increase duration of effort, (3) increase interval count, or (4) reduce rest time.

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by joeyb1000

I have an actual answer to the original question.

In March, my 5s, 1min, 5min, 20min values were 700w, 366w, 298w, 247w. All of my workouts in April were on efforts between 10s and 1 minute. My mid-May values are 736w, 396w, 297w, 248w. So, the answer for me was that anarobic efforts had no impact on FTP.

(Both tests were done on a trainer -- explains why the 5s number is maybe lower than "real world")

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by Shrike

Like TrainerRoad's Spanish Needle. Professes to boost FTP via short anaerobic intervals with short breaks. Quite rough that workout. Usually though this sort of work (like 40/20s) is done at upper end of your VO2 power.

I think this sort of workout isn't high end anaerobic. It's at a level that's a mix of top end aerobic and anaerobic..

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