Right now I have my MaxHR set from a race in another sport but I’m training a lot in cycling now. In i.icu the HR zones seem about 10BPM higher than what my nose breathe/RPE feels like, however I do have a deviated septum so I can’t breathe through my nose super well, maybe that changes things. I have a 20min test for FTP number set for my power zones but I think it’s better to look at HR when doing Z2 so I’m trying to make sure the HR zones are correct.
Actually, it seems like changing MaxHR doesn’t change the HR zone numbers at all? It’s actually LTHR that changes the zones but I’m not sure where the number came from. Should I do a 30min LTHR test in 4 weeks at the end of my next deload week? should I do a max HR test (3min?) and update my max HR to be cycling specific or does MaxHR not really matter as it doesn’t seem to change the zones at all.
Yes, zones in Intervals.icu are set based on threshold values (FTP, Threshold HR, Threshold Pace). You can edit your zones in the Settings page; There are many preset zone models you can choose from, or even define your own:
MaxHR doesn’t affect zones but affects other metrics in the platform (e.g., HR Load from TRIMP).
I believe it’s common to have different Threshold HR values for different sports. Additionally, in his guide to setting zones, Joe Friel states that tests are “best done early in the Base period and then every 6 weeks or so thereafter.”
I found a post by Joe Friel saying that if you take your LTHR from race data it will be 5% higher than if you tested it solo. So in my case that makes my LTHR 9 BPM higher than what it was automatically defined as. That gets me closer to what my zones feel like. although they are still probably off since the race was in a different sport than I’m currently training in
Thanks. in this other post he says LTHR doesn’t really change throughout the season. he has athletes do the 30m test every 4-8 weeks, not for the LTHR but to see the changes in the FTP and pace.
So to me it sounds like its fine to just do one 30m LTHR early base season and then do a 20m FTP test every 4 weeks as usual
As you train, you become more efficient at using lactate as fuel, meaning that you can actually run at a higher heart rate and produce less excess lactate. Therefore, as you get fitter and do more zone 2 training, LTHR should be HIGHER than previously measured. What has happened is that you can now run at a higher intensity (increased heart rate) and uptake lactate more efficiently.
It is common for LTHR to change quite dramatically in beginning athletes. Their lactate shuttling abilities are low, causing rapid lactate build-up. When they start training regularly, the lactate shuttling system improves. After 6 months to a year of regular training, it becomes rather stable, within a few beats.
That’s what I do and in addition I’ve lowered the bottom of Zone 2 HR on my graph based on my RPE and ventilation. There is plenty of support for these methods over strictly heart rate and/or power. In my case, my chart said 128. I changed it to 122 and found a big improvement in my decoupling over 1 to 2 hours. The effort and time required to get my heart rate comfortably above 128 and keep it there was too high and it kept bouncing around and wanting to jump into Zone 3 with the slightest provocation.
It is common for LTHR to change quite dramatically in beginning athletes.
thanks for the info. I did have to take a couple months off any exercise for surgery so maybe I’ll start testing mine every 4 weeks with a 30min ftp test instead of the 20min ftp test that way I can do LTHR and FTP
’ve lowered the bottom of Zone 2 HR on my graph based on my RPE and ventilation
can you explain more? are you saying in your settings>HR you lowered the low zone 2 number from 128 to 122 ? or you did this in a different area?
By doing this, it let you warm up longer and work your way up to your mid zone 2 level?
There are dozens of heart rate charts using the three major standards of heart rate which are Maximum, Maximum adjusted for resting heart rate, and Lactate Threshold heart rate. They have been used to calculate charts with anywhere from 3 to 7 zones with no consensus on the models. Then, of course, we are each all physiologically different. Oh, then there’s the original cycling chart of effort which is Rate of Perceived Exertion.
What I did was take the feeling of Zone 2 to finely set my Zone 2 heart rate and power metrics because, ironically, our Rate of Perceived Exertion and Ventilation, fancy for breathing, are always an accurate reflection of Zone 2 training over a longer period, which is what Zone 2 is all about.
There are many examples out there of the feeling and breathing of Zone 2 and there are differences within Zone 2. The key to all of this is the purpose of Zone 2 which is to allow someone to cycle for long periods repeatedly over the course of a week without exhausting themselves. It enables hours in the saddle. If you are unable to spend the amount of time cycling in your plan due to fatigue, replacing harder efforts with more Zone 2 is the prescription. Builds a base too, all that.
So, yes, I ignored the dozen different heart rates the charts gave and picked from what felt best from my experience.
