lactate threshold not being detected anymore

You might not just be doing the right type of runs for it to be detected! I had this and someone suggested trying the L/T test. Voila, I got a Lactate Threshold. You need to run at different paces, getting progressively faster

HTH

CW

This function never worked for me at all!
I have tried manual tests AND everything - never worked for me! After a few tests I gave up - it's not fun killing it on the track, and then just getting an error message telling you that it wasn't possible to determine a Lactate Threshold :p

So what feedback does the watch give you on the guided test? Are you not hitting the pace or the heart rate? Maybe your max heart rate isn't set correctly. What is it set to and how did you determine it?

CW

You might not just be doing the right type of runs for it to be detected! I had this and someone suggested trying the L/T test. Voila, I got a Lactate Threshold. You need to run at different paces, getting progressively faster

HTH

CW

i read this before but i do actually run at all sorts of different paces. in the last two weeks i did two progressive runs (which i don't usually do) from very slow to above what the 735 has stored as my last LT in terms of HR and pace. still no value determined. i've never tried the LT test but i believe this sort of run mimicks the test. maybe i'll give it a go :cool:

what i find strange is that LT was regularly updated for about 6 months and then it suddenly stopped in dec. i don't remember changing any relevant settings then

I believe the L/T detection mechanic was updated in a firmware a while back. I saw the same as you, ie I used to get them regularly then they stopped. I believe the explanation was that you needed more data points at more heart-rate zones, hence the need for this progress runs (and to be stable at the same heartrate for an extended period within that progression).

Let us know how you get on with the guided test

CW

I have to run quite some time above me lactate threshold pace to get a reading. AFAIK the LT is detected via jumps in the HRV when crossing the threshold (cf. https://www.ncbi.nlm.nih.gov/pubmed/20393353). The ability to do so depends - among other factors - on the chest strap you are using and the algorithm. You should be fine with the Garmin RUN and Garmin TRI. Other than that the only thing I can suggest is: run till you puke. :cool:

I have to run quite some time above me lactate threshold pace to get a reading.

hmm, sounds like the algorithm might not be able to cope with decreasing fitness very well. i'm not as fit as i was in dec when i got the last LT estimate. i can still go above that LT pace but i can't run above it for 25-30min at the moment.

i can still go above that LT pace but i can't run above it for 25-30min at the moment.

The only time I ever attempted the lactate threshold guided test on my FR630, I managed to get a result in less than 13 minutes, of which I spent less than half (and not in a continuous stretch) running at above the LT pace detected.

Let us know how you get on with the guided test

CW

I did the guided test the other day. The test ran all the way to the end but I still didn't get a LT value. To be fair, on the final 3 minute interval I was struggling to get my heart rate up to the required values. I spent some time in the lower part of the required HR range but probably spent more time below it. I hit all the HR ranges before the final one perfectly.

so where you tired, or is your max set to high?

Once a week I do a VO2Max run (5K parkrun flat out) and can get a sustained period well above lactate threshold. I reckon if you can't maintain 90%+ MHR for 5 minutes then your max is too high.

CW