During my last two races (a crit race and a short hill climb TT), my heart rate was useless, it quickly increased to >175 bpm and stayed at essentially HR max for the last few minutes (182–184 bpm). All HR told me was that yup, I can’t go any faster. Power was much more important in both for me.
HR is the least important for me, power and RPE is where I focus on.
That makes two of us.
My heart rate is incredibly predictable pretty much every day. Not only is my heart rate predictable, I also pretty much know when my hr is NOT going to be “normal” from life stress, adrenaline, lack of sleep, anxiety, too much caffeine, too many IPAs the night before, travel, etc, All variables that are trivial to take into account.
Other athletes may not understand how to account for their own variability, but that’s on them.
Ultimately I’m controlling by RPE, and hr and power typically fall within an expected range for any given RPE and when hr and power isn’t within the expected range, I can pretty accurately guess why.
Three of us, along with Ryan above.
Yup. I’ll also throw “time for a new strap” and “don’t know but I’ll keep an eye out for a pattern” as things that happen every couple years.
Four of us.
I honestly find it more useful than power (most of the time), and very consistent.
Power is king. In my view, HR is about triangulation, and a signal of changes in metabolic fitness. Great tool for those times I’m on a (indoor or rented outdoor) bike without power.
How you feel and what you can do for that feel is king.
But yes generally I agree.
Yeah, power then feel. I often struggle with RPE so HR is usually better at keeping me honest. Sometimes my head is so wrapped up in work drama I have to extend my warmup before doing the work.
See below:
Power doesn’t mean shit when you are 7000’ above where you train, and you have to either race for single track, or try to match a breakaway. “Oh, I can’t keep up with the pack, because my power meter says I’m going too hard, I’ll just solo these next 100 miles”.
Add me in as someone who generally has a very consistent heart rate. I’ve even gone from Sea Level to over 10,000’ and after accounting for power differences it’s still pretty much the same. HRV is a pretty reliable metric for me too.
A couple caveats - I can psyche myself up and almost instantaneously drive my endurance HR up 10-15 BPM, combine it with caffeine when I’m getting ready to go after a VO2 workout or something like that, and it can be significantly higher. But, in a way, that’s intentional and getting myself primed.
A good section of an action movie on the trainer can drive HR up. Music that starts getting me pysched up like above - same. But, the instant I snap out of it, it drops back to baseline.
And, I still like Power for pacing most of the time when I’m not forced to stay with a pack (e.g. Leadville, even at altitude)
No, it wont be close to max
I think you have misunderstood.
Never said it would be, that is not the discussion, which is LTHR.
I think, if using ERG, some of this might be related to cadence. When a more motivational track comes on, my HR can surge a bit without me noticing. Once I look down at the metrics, I have noticed that my cadence has often increased which might explain some of the surge.
Part of it, but definitely not all of it. While cadence does have an effect for me, in situations like this it can actually be the smaller component.
To get things back on track with the OP’s question, I’d say that ERG mode is probably not the best way to achieve this, so I revoke my recommendation to use Lola as a typical TR workout for this purpose. 
The best way to achieve a dependable result is to have control of your effort for the 30 minutes and push yourself as if it’s a 20-minute FTP test.
For what it’s worth, I firmly believe that HR data is incredibly useful. No, it isn’t always the very best data source to accurately follow when training with intervals, but HR can serve as a replacement for power when training in certain situations if needed, and most importantly, it shows me what my internal RPE is for a given effort at any specific moment.
As an example, if my goal on a specific ride is to stay in or below zone 2, HR could be an extremely useful tool in that situation as the intent is to keep my body’s effort at a specific level for the duration of the ride in order to stay in the correct metabolic state. Power produced is less important here.
When performing a LTHR test, or an FTP test for that matter, most of the time, the one consistent number is going to be your HR. Yes, this changes slightly over the years, and there are factors that can come into play, but again, most of the time, your LTHR will be consistent from one test to another. The figure that is likely to change if you’re training consistently is your power (FTP).
When performing an FTP test, it’s the power that you’re testing and you’re giving your all during that effort. Your internal RPE should be the same during each test, therefore under similar conditions, your HR for that effort should be pretty consistent.
If your HR is 5 BPM higher one day for a given effort due to poor sleep, is it your HR that is off, or is your FTP slightly lower that day? 
Regardless, a LTHR test is the best way to find your HR zones, and I highly recommend using HR data alongside power when possible. It’s a huge piece of the puzzle and has its place alongside power.
Power is the most reliable data in terms of the work you’re doing, while HR is still the best measure of the internal strain that work is putting on your body. This includes mental strain in addition to physical strain which is why many don’t find it as objective during race efforts.
Yeah I don’t think it’s “trivial”, that’s an oversimplification. Like I’ve been watching my HR and HRV for two decades through all kinds of training, and I generally know when it’s going to run higher or lower, but I couldn’t tell you HOW MUCH higher or lower. For me, relative to power and RPE, HR is secondary. I don’t use it much in situ. When I see it sitting at 172 during a 285W interval instead of 177, I think, “huh, I must be tired today, or maybe it’s a bit cooler than the last time I did it.” I could ballpark my HR within 3-5 beats on any effort any given day, but that’s often not accurate enough to control a workout by.
I have athletes whose HRVs and HRs are metronomic, and fantastic predictors. Mine? Not so much.
It’s individual, so let’s just recognize that and remember it before we apply anecdata to the broad population and pretend like we know better for everyone.
Bingo. 
BaseCamp group coaching has 4 workout reviews a week, over 16 weeks. These have been fascinating to watch. Train by power. Look at Power-to-HR data, both for the workout and in the context of previous workouts - assuming you are repeating workouts (and that includes workouts where time-in-zone is extended). This type of analysis is made easier when sub-threshold workout intensity is the same.
The only time I pay attention to power-to-HR on the bike is when something is clearly off. And then it’s a simple series of questions to ask myself to determine if I care or not.
Yep, that’s how I do it. HR data to me is very useful tracking long rides, EF/decoupling. Can be useful on shorter interval sets. I also use it quite a bit during VO2 blocks (EF specifically). Outside of that, its usefulness is somewhat limited because, especially when it’s not me, I don’t always know exactly what caused that guy to ride threshold 5bpm lower. Is he fitter? Tired? Cold? Better food? Feedback is crucial there.
The most common thing I see is people mistaking lower HR for being fitter when it’s often they’re fatigued. This comes up in VO2 blocks a lot where people going through them the first time will lament not being able to get HR above XXXbpm on the 7th workout, and I don’t really care. That’s as much fatigue as anything by then, so focus on cadence, going max, and breathing like a dying fish.
Yes.
Here is an example of lactate and HR curves shifting over several training blocks:
Short version (I took notes):
Yes 59% zone1 - what some still call junk miles.
The lesson here is that if you come out of an off-season, and have productive base training, then reduced HR at a given power CAN BE (and likely is if your HR is well behaved) a signal of improving fitness. And a signal to adjust training and/or do an FTP test.
