Hi - Can the FTP test establish my lactate threshold HR ?
Yes give or take
Hey @Segovia,
Good question!
It depends on which FTP test you’re talking about. Finding your LTHR usually requires a 30-minute threshold “time trial” like effort. I have been able to get a good reading on my own LTHR from a 20-minute test in the past, so that could be an option if you’re looking to test your FTP and get a ballpark LTHR at the same time. Just make sure you’re warmed up before the 20-minute interval.
Here is a great article about this process:
Am I right in thinking the LTHR is the HR reached when I stop my FTP challenge?
From memory the TR FTP test is pedal until you can’t sustain it any longer which is the description often used for LTHR
Can you suggest a TT and can I see the AVG HR for the last 2mins in TR ?
HR is probably going to be higher indoors depending on how much cooling you have (fans, A/C, etc.
I agree with @Bbt67.
Lola would be great for this type of test.
Just keep an eye on the power target. This 30-minute interval is actually a slow ramp from 98% of FTP to 100% and it could be worth bumping the intensity up to 100% at least for the last 20 minutes of the test.
Question: what are people using whatever LTHR number they get for, given that HR has so many input variables?
I believe LTHR is a better starting point for working out your HR training zones as MAX HR isn’t really definable due to too many variables also the common rules for Max HR , 220- minus age etc have proven to be unreliable.
Secondary validation of Power and RPE. If my HR is significantly away from where it should be, I’m probably:
- dehydrated
- hot
- fatigued
- fresh
etc etc
It won’t normally tell me what is wrong but it’s a useful triangulation to confirm there is something not quite usual.
Post-hoc triangulation. Got it. ![]()
I’ll look at HR post ride, too. Tracking EF and/or decoupling for similar rides over time can be interesting/illuminating.
I see. I always have power (and everyone always has RPE) so I’m not in the habit of looking at HR except after the fact.
Triangulation. EF. Decoupling. Zone setting. WindWarriorFTPestimation™ since 2017.
For all the talk about variable HR, when I do 85% ftp long-ish tempo my HR after a few minutes is usually in a pretty narrow range of 144-147bpm. Both inside and outside. Can make similar comments about endurance and SS and threshold. When my HR is outside that range then there is a reason, some stated above by @foldingbikebass and other reasons like I did some glycolytic (above threshold) work immediately before the tempo.
On the bike, during sub-threshold intervals, I use power, HR, and breathing to triangulate the effort. Power informs feelings, and HR/breathing confirms power.
My long “easy” days can be moderately hard. Capping effort to ~80% LTHR (usually around 60-63% of FTP for me) is simpler than going by power. And it curbs my enthusiasm, otherwise I’d go around 68-80% of FTP, which is happy hard but burns me out in 2-3 months.
Basically, you’re trying to work out and triangulate your LT1 as a cap?
Whatever HR zones structure anyone picks, it’ll anchor around one important inflection, but quite possibly fail to correctly illustrate the second. I may be mis-quoting but Joe Friel said LT1 was 30bpm below LTHR. I’ve found that to be roughly correct, but not 100%, based on talk-testing, not on actual Lactate testing. So who knows. When I first got into training, I spent a lot more time worrying about trying to understand the alignment of the various HR models against FTP. Why they align differently for running vs cycling etc etc. Not sure I’m that much wiser. So now, RPE and breathing are more important to me.
Huh, it is in same ballpark indeed. Never knew ![]()
I seem to unable to use talk test or nose vs mouth breathing to understand when crossing LT1 – when I get self-conscious, those patterns automatically change. I actually learned upper Z2 HR cap from experience, how frequently have lost motivation during season and only then put marker for myself (80% of LTHR or 60-63% of FTP). And when exceeding occasionally 24h+/week, then it is even lower, 57-60% of FTP.
In other words, go ride at threshold for a long time and see where your HR settles.
The idea is to give people the most robust, generalizable advice, not to expose them to more confusion with N’s=1.
Tell that to people that say HR is too variable even though the athlete is training on a regular schedule, indoors under controlled conditions. I had a coach with over a decade experience, large number of athletes, and in his professional view I wasn’t an outlier. Sure there are times when HR is “off” but those should be exceptions and flags that something is off (stress, fresh, overreaching, dehydrated, etc.).
