Lactate threshold test / Can't reach required HR

You should try lowering your max HR on the watch just before the test. LTHR is estimated as 90% of max HR so perhaps the test running on the watch aims too high, and you can't reach that. 

Thanks I will try to adjust my max HR and will redo the test. BR

8978269 said:

I'm 32 if it makes any difference

I tried the LTT test a few times and also could not get my HR high enough.

If you cant at 32 yrs old then imagine me at 54 yrs

I decided to change the zones based on Resting %HRR instead.

How long do you normally run? I wonder if your muscles get tired before you can stabilize at the LTHR for the watch to determine it with confidence.

It depends. Sometime 1h sometime 30-40 mins and I run between 5 and 10 km. Everything depends on the track the harder the shorter.

I do MTB as well between 15 and 40 km and up to 4 hours.

I'm not the most trained person in the world but I feel very strange I never reach 175+ BPM. I mean when Garmin says I'm at 168 BPM I can barely breath!

Doing some rough math my max HR should be 188 which is well above my current limit.

The "220 - age" formula isn't accurate at all. The max HR varies a lot from person to person. It is possible that your max HR is just much lower than what you'd get from the formula. It may very well be in the upper 170s.

Looking at your screenshots again, I think your LTHR should be around where your HR stabilized between minutes 23 and 26, perhaps a bit lower. It is hard to tell exactly looking at the graph but perhaps around 165. 

I just did a LTT today on the same firmware both Fenix and hrm pro to set the new power zones. (you require the same test)

the second to last interval was allright to hold, more feeling like a long interval type, not all out max effort. the last 3min interval felt hard, as it should be, when in an anaerobic area. the test delivered for me as well a lactate threshold als well anaerobic power threshold in watts - i chose to accept those and they were updated in the connect app as well.

i second the guess, that your max hr might be set to high by the "formula" - for me with todays test it matched the former zones just deviating 1-2 bpm, nothing major. if you have done a 5k race or 10k race in the last time, check the rate rate at the end - that should be more close to your max HR. 

i hope this helped! 

Thank you all. I changed my max HR to 177 and will do another ltt test on Friday. Will let you know.

Bests

Alright so yesterday I double checked my max HR and it was set to 177. Today I did my ltt and the watch tried to push me again at 190.

Of course I failed the test again, I then checked my max HR and surprise surprise it was again at 189!

Not sure when it changed but next week I will redo the test but before departure I will check again my max HR 

I'm even more confused now.

I adjusted the max HR to 170, double checked before the test.

All good until the last interval where I was supposed to reach 171-180 and of course I failed.

The ridiculous part is that at the end my Fenix told me that my max HR has been adjusted to 189.

Don't know... Any idea?