Fenix 5 Lactate Treshold Test

Former Member over 7 years ago

Hi, I've been out a couple of times now and when doing the test i get a result of 64bpm!!
I have a fenix 5 with the garmin heart rate strap.
I'm not the fittest guy in the world but that seems very low. I run 10k in around 53mins with an average 155-160 bpm so was expecting around 140-150.
I have a resting heart rate of 57 and I'm 50 in a few months time
Am i missing something or has anyone else had this problem.
I wanted to set my heart rate zones from the results but obviously that wont work lol
Any help is really appreciated.

0 mcalista over 7 years ago

If you are doing a 10K in 53 minutes at 155-160, your LTHR is probably 160-70. As a rough guideline, most people have a LTHR at between 86% and 92% of MaxHR (on the lower end for less trained individuals, on the higher end for more trained individuals)

I'm guessing that it must have picked up an inflection point in your HR curve that wasn't your LTHR.

For LT autodetect to work, you need to run a few minutes a bit below LT, and a few minutes a bit above. I'd suggest warming up thoroughly, then 5 minutes at 150-155, then 3 minutes at 160-165, followed by 3 minutes at 165-170. That should give the watch enough data at the right ranges to give you a LTHR.

0 Former Member over 7 years ago

Thank you mcalista I'll try that.
I was doing the test from the watch and keeping it in the correct HR zones i.e. in the green, but both times it gave the same result!!
??????I'll try again and see what happens

0 drkglb over 7 years ago

I've had the same issue, although not doing the LT test but just running with the watch on, and getting automatic new LT detection. The problem is that the Fenix 5s always detects LTHR around 60 bpm.
Also using the Garmin HRM Run strap.

0 Fenix X over 5 years ago

For me test not deteced anything.... Watch keep the value I set manualy. I did as you Paul all runs in right speed and hR range with HTM tun strap. I Read somewhere that we have to lower max heart rate in settings because watch detecting only higher value than set in the watch let's try...