I ran for 20 minutes with a Forerunner 255 and a heart rate monitor (HRM-Pro). After finishing my run, I went to the charts and saw that the zones on Garmin were as follows:
Zone 3 (9:59 minutes, or 47%)
Zone 2 (6:42 minutes, or 32%)
Zone 1 (2:09 minutes, or 10%)
But for some reason, Intervals ICU seems to differ, even though I have the same ranges/exact BPMs for each zone. Here are the zones that Intervals ICU thinks I ran in:
Zone 3 (5:57 minutes, or 28.4%)
Zone 2 (9:50 minutes, or 47.0%)
Zone 1 (5:08 minutes, or 24.5%)
As you can see, itās pretty different and quite inaccurate. Can somebody please tell me why itās like this and how I can fix it?
Here are the photos for the zones on both Garmin Connect app and the intervals.icu
ThereĀ“s a 2 min difference in total time in between both. That almost surely means that you have Ā“Auto pauseĀ“ enabled on your Garmin.
Garmin and Intervals handle paused time differently.
So, does that mean I should just turn off auto-pause altogether to get accurate zones on both platforms? Sorry, Iām a new Garmin user; I just got the watch two days ago, so Iām still figuring things out.
IĀ“ll have to correct myself. The 2 min difference probably lies in the fact that Garmin counts the lowest zone from 134 and intervals from 0.
Can you show screenshot from the HR trace on both platforms?
And can you check if your watch has Ā“Smart RecordingĀ“ turned off?
Intervals works best with second by second data.
The first thing I did when I got the watch was switch from data recording from āSmartā recording to āEvery Second.ā So, I guess thatās not it. I even ran now for half an hour, half asleep while double-checking every setting, and to be honest, nothing changed; itās still different, and I didnāt even pause or anything.
Iāll list the HR from the runs on all three platforms. Iāll also list the run from 5 minutes ago.
Pretty sure itās a rounding issue in the Intervals zone settings.
From both runs, you can see that you spend quite a bit of time exactly at 176 - 177 bpm.
This one shows 5m57s above 177 while it actually is around 10m.
Did you use presets based on % for HR settings?
Iām not sure if it will make the difference but you could try to set the HR values themselves iso letting the % be calculated. The fact that the percentage could in the background be 177.5, might explain this peculiar situation. Once you changed the zones by typing in the actual numbers, go to the bottom of the activity chart and choose Actions - Update zones.
If that remains unchanged, set your lower zone limit 1 bpm lower, just to confirm my suspicion.
This is really an interesting case that might need @david 's attention.
Brother, I didnāt understand what you meant. I absolutely struggle with mathematics. Is it about lowering the number in Zone 3?
I already have āMyProCoachRunā set, and I believe it allows the use of %HR. However, Iāll change it to āCTS Run,ā which also uses % of threshold heart rate, just to see if that fixes things. The percentages I used were all automatically calculated by the 80/20 endurance zone calculator. The only reason I donāt use the 80/20 preset is that it makes things overly complicated for me. The Five-zone system has become very familiar, and Iād struggle to change it.
I still donāt think this worked ): to be honest, this is far more complicated than I expected. Does it matter if Iām directly synchronizing through Garminās Connect app and not Strava? if this still doesnāt work is there a way I could manually edit time in each zone per activity? My whole objective was to analyze percentages of time spent on each HR zone weekly.
No problem. Donāt change your zone system, use what you like best and what youāre used to.
Iāll try to explain in plain English
Garmin rounds the result of the percentages to a whole number, both for display and for calculations. While Intervals rounds only for display but uses the exact number with decimals for calculations. So a HR of 177 goes to Z3 in Garmin because the lower limit is exactly 177, but in Intervals the lower limit may be 177.2, meaning that it goes to Z2.
If you set them like this: (itās just 1 bpm lower)
and end up with very similar result as Garmin, that would confirm that itās just a rounding issue.
I tried updating the activities as you have suggested, but so far, nothing seems to work. Iāll try to go for two runs tomorrow: one where Iāll use Garmin for synchronizing, and the second run Iāll disconnect Garmin from this website, link it to Strava, and sync from Garmin to Strava and finally to here. Hopefully, thatāll work. Iāll let you know how it goes. Thanks for sticking around; youāre giving me hope in my new piece of junk watch
I also edited the zones exactly how you have mentioned. Still nothing
Sorry for taking too long to update; I had a busy couple of days. Anyways, after some fine-tuning and realizing that I could manually set my zones using BPMs instead of %LTHR, %HRR, or %HR Max, I can confidently agree with your conclusion about it being a rounding-up issue. Even though some of the zones are not pinpoint accurate (with minor variances of around 10 seconds or so), Iām still satisfied with it.
Iām glad I found this forum; it helped me realize how wrong I had configured my zones. They were so off to the point where my āzone 2ā was actually my zone 3, and my āzone 3ā was my zone 4. Iām very glad I have everything set up correctly now!
I just have one last question: Is it normal to have some zones be pinpoint accurate, as shown in the pictures below, while other zones (zone 2 and 1) are off by a few seconds? If thereās no way around it, then Iām fine with it, but if itās possible to achieve 100% accuracy, please let me know. Thank you.
Do you actually mean/think that the Garmin data is 100% accurate??? Why wouldnāt it be Intervals who is the correct one? I donāt know, just pointing outā¦
Why is Garmin dismissing all datapoints with a HR below Z1?
For time in zones, and especially with HR, those seconds have absolutely no impact. The important thing is that your data stream is the same on every platform.
TIZ by power will generally be as good as identical on all platforms.
Yeah, well, a few months ago, I did a stress test in a lab to find out my true max heart rate and use the Karvonen method (%HRR). But that didnāt go too well. The doctor I went to had horrible equipment; his treadmill didnāt go so fast and didnāt elevate high enough to generate what you would call maximum effort. Since Baghdad is as flat as a pancake, doing hill repeats isnāt an option, really.
Anyways, he told me to shave my chest before visiting, and so I did. He then proceeded to put some gel and stick those circular things (I think theyāre called electrodes) on each part of my chest to measure my heart rate. The test began, and he started speeding up and elevating the treadmill after every 3 minutes while checking my blood pressure. My test took only 15 minutes, and it was a total failure (not heart rate failure but just very disappointing) since the equipment he used seemed so cheap as the electrodes didnāt stick and kept falling.
So he called his assistant who then just started pressing them against my chest so it doesnāt fall. He told me not to run at all, which I found stupid. The reason was the electrodes will keep falling. Anyways, his machine recorded the highest heart rate as 186 BPMs. And I told him that canāt be my max heart rate. The idiot decided to use the 220-age and stop me when I reached 85% of my āMax HRā as if I hadnāt told him before the test that Iāve found it as useless crap. Everyone sided with the doctor, including my family and friends, who told me that I didnāt know anything and that the doctor is an expert, etc., etc. Heck, some even told me to stop running because āitās dangerous to have such a high heart rate.ā
At the time, I was only using a watch that uses optical HR, and the highest that I have ever gone was 203. And I still take that with a grain of salt because optical HR is quite inaccurate. And I honestly believe I could record a higher HR with my new chest strap.
Ever since I found out about the Lactate Threshold field test by Joe Friel, I havenāt looked back. As I didnāt need to know my max HR, and I could do it solo, which I absolutely loved since there arenāt many if any places where I could do it in a lap. And I found it to correspond with how I feel. So, I put my max HR to 240 because itās basically irrelevant since anything >186 BPMs is just zone 5. Iām looking forward to redo the test in the next 5 weeks and see my new Lactate Threshold.
I figured since Iād be using third-party apps/websites, the data would be a bit messed up, and that the data from a first-party app like Garmin Connect would be more accurate because itās directly from the chest strap to the app. But, as you pointed out, I could be wrong. (I thought that with more steps in transferring data, there is a greater margin of error.)
sorry for the messed up quotation Iām still figuring this forum out. Are the commands like reddit? Meaning for something like quoting/replying to a specific thing.
Some docs will side on caution as a ājust in caseā.
when I did my treadmill test, I asked permission to also use my chest HR strap and it was spot on (i think it was a wahoo tickr)
You could always grab the data from Garmin Connect and intervals and then manually decipher (there are converters on the web) the HR data and tabulate it (i typcally use excel to do this w/ the histogram feature)
