guided test treshold not detected

Are your heartrate zones accurate in the watch? I should look at this first. 

The watch doesn't use heart rate zones for its analysis. But if the maximum heart rate is set too high (auto detect?), it could explain what happened.

Well, the zones are defined by Garmin based on the %LTHR from my previous LT test. That is a few months ago, and I suspect my LTHR is higher now due to my intense training. The max heart rate is based on my own test, and is more or less confirmed by running  final sprint km's in half marathons, and by the auto detect feature, which I had switched on for some time (and now of again).

     The exact same thing happened to me today during a guided LTHR test where I had to run for 3 minutes at the last stage at a heart rate of 205 to 213 beats. Since my max heart rate is around 201 bpm, I resigned myself to the test, of course the watch didn't register the new LTHR values, even though I ran at 189 bpm for the penultimate three minutes.

     The reason was a wrongly set maximum heart rate in the watch, where I had set 213 beats/minute.

- Make sure that your HR Max is set correctly. Turn off auto-detection. If you have run a 10k or 5k race at max recently, take the HR at the end of the race and add 5bpm. Otherwise, it your doctor lets you, perform a field or lab HR Max test. These are very hard tests.

- Make sure that your chest strap is sending HRV information (R-R intervals). Apparentely, even so, not all HRV capable chest straps send the *right* R-R info. Not an issue if you use Polar H10, HRM Pro straps

- Doing the test with HR targets is hard. For this test to be accurate, you need to maintain a steady pace during each step. The HR will ramp up. If you try to get the HR going, your pace will be too high early and you might not be able to sustain it for the interval.

- To switch to pace targets: start a run activity, settings>Trainings>Workout Library>Daily Suggestion. Select the workout. Press the start button, a menu will show up to do workout, see steps or see settings. Select settings, change target from HR to pace.

- Now the lactate threshold test will give you pace targets. Follow these targets scrupulously.

If this still doesn't work, make sure the HR Max is correct. This value is the cornerstone of all the Garmin metrtics.

The pace targets might be off. For example, you could run longer than the last interval at that pace (too easy), or you cannot reach or sustain the pace for that long (too hard). This is a sign that your metrics are off.

If they are off, again, verify the HR Max.

If HR Max is OK, for a couple of weeks, run the suggested workouts, but replace at least one of each workout type (base, tempo, threshold, anaerobic, sprints) by a maximal effort run: instead of running the target pace, run the maximal steady pace you can sustain for the duration of the run intervals of the workout. This will help the watch gather the correct information. Not worth doing this is you are not sure of your HR Max.

After you have a threshold value from the test, let's say 7mn/mi, test it for real. Convert your threshold pace to a speed, divide this speed by 0.95. (in our case, 7mn/mi is 8.57mph and 8.57mph/0.95=9mph which is 6:40mn/mi. On a flat course, you should be able to run 20mn at that steady pace. It should feel like a maximal effort.

A note of caution: the recommendations above work really well, but you need to be a trained runner to implement them. Maximal efforts are brutal from the HR Max test, to the threshold test to a marathon PR race! Perform them at your own risk with adequate recovery in between...

If you don't consider yourself a trained athlete, the metrics might be off but not completely useless. Use an age-based formula to estable your HR Max, keep auto-detection off and go run.

Etupes25 said:

To switch to pace targets: start a run activity, settings>Trainings>Workout Library>Daily Suggestion. Select the workout. Press the start button, a menu will show up to do workout, see steps or see settings. Select settings, change target from HR to pace.

Already set to this. And still LTHR test is given me BPM targets. I experience I need longer times running to let my heart rate increase. The interval of the LTHR test seems to be to short to reach higher levels . But then again, I could not keep up the pace I ran in the last interval for any longer.  I am confident about my Max HR (as I reach high 180's after intens runs) and max HR is set to 194. That's why I am wondering if it could be that my heart is trained big deal past few months, and it is staying low because of that. 

DaKo said:

And still LTHR test is given me BPM targets

I have an EPIX Gen 2, and the targets do change. It may be a limitation of the 955 or maybe a bug?

DaKo said:

That's why I am wondering if it could be that my heart is trained big deal past few months, and it is staying low because of that

It could be yes. With training, the heart doesn't have to pump as fast to get the same volume of oxygen to the muscles, and the anaerobic capacity may have increased. If your HR gets "sluggish" however, it could be a sign of fatigue or over training. The HR doesn't raise up as fast during intervals for example. I picked up training after an injury and the first anaerobic workouts got my HR close to my max. A few months later, my HR Max was looking very up there :-)

Anyway, you can try to lower your HR Max by a few bpm to see if the detection happens.

Update of my story.

Did a LTHR test run again today. The previous one has been a while ago, since then I ran a half marathon with the first 15km at a pace of 4:45/km at an average heart rate of 180-181 bpm. . So I expected my LTHR to be near that pace and/or heart rate.

Meanwhile, my Garmin HR sensor broke (sensor cover in the belt got loose. It still gave readings, but I got it replaced by Garmin. 

Conditions of today's test were:

- new HR sensor
- a month after the previous failed test
- two weeks after very intense half marathon (yes, I broke down the last km's  )
- HRV too low for two weeks now, despite of resting, it does not come up.
- Weather: ran the test into the modest wind, got a cold intense rainshower for 5 minutes

Results: new LTHR detected. Pace 4:58  and LTHR 177bpm (previous test in August was 5:08/168bpm). So major improvement as expected, but I would say it should be even better because of my 15km pace. But we will see what happens next test.

I suspect my old HR-strap did not gave accurate readings anymore. And probably that caused the failed test. It was kind of ridiculous that I ran the faulty test at 3:30 per km, and still did not reach HR zone 5. Today that was no problem  

For now two questions remain:

1. Is my expectation of an even higher LTHR plausible? Because I read that the LTHR should be somewhere the pace/heartrate that one could run for about an hour. Which I did in the half marathon.

2. I have checked my new LTHR (zones) in the connect app, and for Running it says maxHR at 209bpm, while I always put in 194. So does accepting a new LTHR after a test, also change the maxHR? ANd if so, what happens if I accept the LTHR of 177bpm, and manually change the maxHR back to 194? 209bpm is a hear rate I will never come close to.

Auto update of max HR has separate option and HR is not updated when turned off even with LTH test.

I thought so. Probably the higher HR is a leftover from the period I had auto update switched on. I will keep an eye on it.