Forerunner 965 - Not auto detecting lactate threshold and giving out of date data

Hi all,

I’m using a Forerunner 965, and I haven’t received any lactate threshold update since May — not even a new data point. Everything is set to Auto Detect = ON, and I’ve done multiple runs that should be ideal for triggering a detection (sustained threshold efforts, long tempos, and even a recent half marathon).

I’ve reviewed my data in Garmin Connect, and no new threshold estimates are being generated at all — it’s just stuck on the last value from a few months ago. I’m getting updated VO2 max data as normal and last week got a “detected new max HR” message.

A few things to clarify:
• I run 6-7 times per week, including quality threshold sessions
• Auto Detect is on
• I haven’t received any “threshold detected” prompts in months
• I’m using wrist-based HR, but I’m now wondering if I need a chest strap for better data
• It’s disappointing that the manual lactate threshold test seems to have been removed from the Forerunner 965 – is this permanent or just hidden somewhere?

Questions:
1. Is it normal for Auto Detect to go this long without any update?
2. Has the manual test truly been removed, or is there a workaround?
3. Would switching to a chest strap significantly increase the chances of detection?

Appreciate any insights — I really like the training features, but the lack of LT updates is making this one feel a bit unreliable.

Thanks!

  • Try to do a 20min threshold workout at a pace little bit faster than your threshold pace, then the watch will have data to update or not, i find that when the watch find a real stable threshold value it doesnt change until you triger it by doing a hard threshold session where it has enough data to re-value, you can also try a manual threshold test as i do, in garmin connect make this new manual workout,

    10 min warm up

    4 min at zone 2

    4 min at zone 3

    4 min at zone 4

    4 min at zone 5

    10 min cool down,

    This is the same threshold test as Garmin had before the automactly threshold detection, try and let us know, regards

    ***Chest strap will always has better data than the wrist based HRM, but dont worry i have chest strap and i dont get any new value after a month, and i do 2 threshold workouts every week...