Big gap between aerobic and anaerobic threshold

I’ve had a gas analysis done in a lab today to determine my LT1.

After receiving the results, I noticed there’s a very large gap between my aerobic thresshold (144W at hr 133) and anaerobic thresshold (332W at hr 181)

Is such a large gap between aerobic and anaerobic thresholds normal, or should I question the accuracy of these results?

I do think I have a high anaerobic capacity, but this is a bit much.
In trainerroad I often have problems with thresshold beyond pl 5 and sweetspot once they turn into long sustained efforts. While with the prescribed vo2max workouts I’ve got problems getting my HR high enough.

Post your power curve


your ftp is around 332W? and what’s your max heart rate?

no not by a long shot, my tr ftp is set to 269 and ai ftp suggests 275
maxhr = 187

I have a similar problem , and my solution has been to view all my Zones independanty, like somebody famous kept saying in another thread, Zones are descriptive not pescriptive (though my knowledge of FTP is so limited that I probably go that quote wrong)

Found my (repeatable) 1,2,3,5 minute power, my hour power and my zone 2, and don’t worry how they releate, in some ways it’s like Wahoo’s 4DP


How much data is that power curve derived from? All of this season? Last 3 months? Last 3 weeks?

Lt1 is closer to correct. Anaerobic threshold is very wrong.

FWIW. What did you plan on doing with this information? Are you still running through a TR plan? It’s not like that result would modify your plan.


Is it possible that this 332w level is actually maximal power output at the tte? Could fit to that tr ftp level. But no data what kind of lab test was so can’t say too much about it.

Typically gap between LT1 and LT2 is wider in less trained and narrow in well trained groups.

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All of this season

Right now I am only doing one or two workouts inside using trainerroad

I’ve read a lot on the forums about ISM’s theories on the importance of spending a lot of time in zone 2 somewhere around fatmax or lt1 to improve mitochrondial function in slow twitch fibers which helps with lactate clearance and increasing your fatmax power. I intend to do a lot more zone 2 in the coming months, but I wanted to determine a power range / heart rate I should target during these rides in ISM’s zone2.

Also I wanted to accurately determine where my heart zones lie, so I know what minimal heart rate I should target during thresshold and vo2max intervals.

It was a ramp protocol till 400watts which took about 15 minutes I think.
After 400w I was unable to continue.

I’ve asked the lab for more data (graphs), they forwarded it to the MD who supervised my test but he is not available due to sickness.

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That’s simply an artifact of the overall downward shift of the lactate - intensity relationship.

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