Thank you for the correction, I fixed the typo, obviously we were talking about Aerobic Threshold.
As far as the sampling window it was originally recommended, I believe by Marco Altini, to use a 60s computation window, hence the 1min steps.
Others recommended steps in “watts”, but it seems to make more sense to use a percentage of FTP, so to have similar steps in terms of effort for people with very different FTP.
Taking 2min steps would stretch the duration of the test significantly (particularly if you keep the 2% steps), but can definitely provide more accurate results.
please one question - I am now quite confident I can precisely estimate my LT1 thanks to Fatmaxxer and real time values during a ramp test
Now I would like to dig a bit deeper into what is happening with my power / HR / DFA Alpha 1 over time during a long hard ride… I know, in theory this could work in a replay mode in Fatmaxxer, but I never managed to do it really properly.
Besides, I would like to look a bit more in details, check different parts of my ride etc - because lately I was surprising discrepancy in between RPE and Alpha1 values from Fatmaxxer that I see on my Garmin screen (pushed notifications)
So, does anybody please have a resource with a clear how-to “manual”? I saw some nice plots out there, but I don´t have Kubios and for now zero skills with Python. But I saw somewhere Marco made public his Python, so maybe there is some way how to use the same calculation that Fatmaxxer does and align it with other metrics recorded during the ride…
I was wondering why HRV data is not not available from my Fenix 5x+ watch.
After some digging, finally realised that my data is synced Garmin → Strava → intervals and strava must have stripped it off.
Manual upload FIT file from garmin and it’s there now.
The length of this thread and the mixed contents seems to confuse people that have less knowledge of the whole HRV thing so I think it’s appropriate to give some basic understanding about the two different HRV topics within this whole discussion.
Resting HRV is measured first thing in the morning (or overnight with Oura). This HRV topic is already quite advanced and researched. Having 60 days or more of morning HRV data allows you to judge your stressors and recovery. Main source for information is Marco Altini’s Blog blog.
Exercise HRV is measured during exercise and the purpose is to estimate your VT1 treshold. Knowing this treshold allows better implementation of Polarized Training because you have an upper HR/Power limit for LIT training. This topic is relatively new and there’s not much information/research available yet. Main source for this is Bruce Rogers’ Muscle Oxygen Training: Muscle Oxygen Training blog index blog. There are a couple of apps that can measure this advanced calculation of DFA-a1 value whether or not in real time. FatMaxxer, Runalyze, HRV Logger are the best known yet but there are other developments. Ther’s two ways you can go with this. You can record HRV during an exercise ramp and do the calculations afterwards to estimate VT1 or you can have the DFA-a1 value in real-time and adapt your intensity to get close to 0.75 and continuously follow up if you are below VT1.
These two topics are completely different and should not be confused but they are both helping to guide your training. That’s why they are mixed in this thread.
Looks like Fatmaxxer is going to make it into PerfStudio Pro in the near future:
You can plot the content of the Features file from FatMaxxer but you need to align the values with those from your exercise FIT file.
To facilitate that I always start FatMaxxer first and when it get’s at 2:00 min, where it records the first DFA-a1 value, I start my head unit.
Things can and should be approved for easier use. But as said elsewhere, this is all pretty “novel”.
HRV4Training computes its HRV score via a mathematical transformation of the rMSSD score (which is one of the two HRV measures Intervals picks up from HRV4Training). I’m sure there used to be a more detailed description of this at the HRV4Training website, but I can’t find it just now.
HRV4Training seems to us this computed HRV score (in comparison with a baseline value you’ve accumulated over a number of readings) to indicate whether you should rest or train that day. So in that sense, separating it out as “Readiness” seems appropriate to me, and it is how I’ve always used the HRV4Training app.
I added an aggregate for “7 day coefficient of variation” which is the standard deviation of the field over the last 7 days as a percentage of the mean (tx @Vito_Nacci ). It basically measures how much the field (e.g. HRV) is jumping around.
HRV4Training uses “Daily score” for training advice
Some thoughts on “Readiness” scoring and comparison between different apps: (this is probably the article @Dr_Robert_D_Saunders was looking for.
@david Thx for adding the CV!
The only thing missing to reconstruct the view on HRV4training is the possibility to add a “Normal Value” band. This is calculated as 0.75*SD of the RMSSD from the last 60 days.
So the confusion goes deep when HRV4training calls (the label) as “HRV” in the chart (view) and not “Score”, “Readness”, etc…
Very good article @MedTechCD , which makes me wonder why Marco labeled as HRV and not “Readness”.
I did speak to Marco on this once before as when I first started looking at HRV I went from nearly 100 in one app to 7 in HRV4Training. The answer was exactly that, to prevent the huge difference in numbers. By normalising the numbers into an easier to understand value made sense to him. You can still view your raw HRV numbers in the app if you have a pro account or something.
In fact @Gato_Felix, your observation is correct. But when we started with variability it was important to make things easy and understandable on the fly. I talked about this with Marco years ago (he is the only one with whom I can speak Italian ) and this is the real motivation. I would just like to say (I have been using it for a decade now) that the given score of the day is an algorithm that is not always accurate, you have to take it in moderation, and it is determined by the difference between the activation of the sympathetic and parasympathetic. The absolute value of HRV is not the only data that is taken into consideration. Much more useful to see the set of data, normal, base and CV7% that David has just given us.
Would it be possible to add support for the dfa alpha 1 data in the activity page?
I record dfa every ride via Fatmaxxer and do some analysis on it in excel.
Would be nice if I could do this inside intervals.icu (upload the .feature file) and link the dfa data with the HR and power data from the fit file.
I would also like to track some statistics over time, for example dfa value at a certain power output.