Other/Mixed DFA alpha1 for running below ventilatory threshold

[Marino]

Does anyone have any long term experience using DFA alpha 1 measurements of HRV for trraining at ventilatory threshold? You can measure it with a Polar chest strap and HRB Logger app. The idea is that if you get a reading of 0.75 or less you are at Ve1. Sort of lines up with Strong Endurance and MAF principles. Or the talk test.

 

[psmith]

No personal experience, but I've heard from several sources that it's not that great for running, probably because of interference from torso movement. See here: DFA a1 problems during running - why?

It's been my experience that most of these measures tend to converge anyway to within a reasonable margin of error, especially when considering the intrinsically continuous nature of metabolic pathways and day-to-day variability. If you're interested in going deeper into this stuff, you might play around with heart rate drift (for steady state cyclic efforts, don't think it would work very well for kettlebell stuff) and blood lactate ($300ish for a meter and ~$10/test for consumables, so not cheap but not stratospheric either).

 

[offwidth]

If you train in a group or with a like-minded training partner you can share the cost of a blood lactate meter.
(For some additional perspective… the approx. $300 for a meter is less than half the cost of a high end gps watch)

 

[Marino]

Thanks @psmith. That's an interesting page. The metric seems to be relatively untested at the moment. My experience is that my 0.75 threshold occurs at a heart rate which is higher than I would expect based on the 5 zone construct.

 

[psmith]

(For some additional perspective… the approx. $300 for a meter is less than half the cost of a high end gps watch)

This is a very damn good point, and at least within the Garmin lineup the marginal benefit of the high end watches over the low end ones is basically just looks. Maybe solar, but you still gotta charge them, so how much is that worth?

Of course, looks matter.

Thanks @psmith. That's an interesting page. The metric seems to be relatively untested at the moment. My experience is that my 0.75 threshold occurs at a heart rate which is higher than I would expect based on the 5 zone construct.

What do you mean by "based on the 5 zone construct"? How are you finding your zones?

 

[Marino]

the 5 zone construct I'm referring to is to take maximum heart rate and use that to determine 5 separate training zones. Zone 2 is 70% to 82% of MHR on this basis.

 

[offwidth]

the 5 zone construct I'm referring to is to take maximum heart rate and use that to determine 5 separate training zones. Zone 2 is 70% to 82% of MHR on this basis.

I think that what @psmith was getting after is which 5 zone system are you referring to?
There are a number of different systems out there. Some are based on MHR, some are not. And (at least) some of the MHR ones use different values.

MHR is kind of hard to determine. AeT (from my perspective) is easier to determine and a better base for a zone based system

 

[psmith]

the 5 zone construct I'm referring to is to take maximum heart rate and use that to determine 5 separate training zones. Zone 2 is 70% to 82% of MHR on this basis.

From a theoretical standpoint, I don't like this. I don't really care what fixed number percentages the system calls for, but there's substantial across-individual variation in where metabolic thresholds occur as a % of max HR, and one of the main effects of training is to shift those points, and it's all even less connected to reality if you're using a formula max HR rather than a tested max HR.

From a practical standpoint, meh. 65-75% fake-max HR, 65-75% max HR, whatever % HRR, <5% cardiac drift in an hour HR, MAF, whatever % LTHR Friel suggests, even a flat number range like 130-150bpm are all probably gonna get you to about the same place plus or minus 10bpm or so, and that's probably fine as long as it's letting you hit your target volume without getting beaten up and you're getting faster.

 

[Marino]

I was using the 5 zone system in Mike Prevost's PDF called Endurance where he quotes it. I think it comes from the Norwegian Olympic Committee.

My MHR tested from having run as far as I can as fast as I can is about 183. That's a bit out of line with the 220 - age which would put me at 170. Under the 5 zone system I mentioned ventilatory threshold would be at around 150bpm for me. Using the DFA alpha 1 metric where ventilatory threshold is 0.75 my heart rate is around 160bpm which on the 5 zone model puts me quite far into the dreaded no man's land of zone 3. I'm just interested in the correlations. And I'm sure psmith is right that thresholds move about with training although the DFA 0.75 threshold supposedly moves about with them.

In practice perhaps all you need to bother with is the talk test or not huffing and puffing too much.

 

[silveraw]

MHR is kind of hard to determine

Funny enough, my last conditioning session my HR went past my 220-age MHR. I was wondering why my Polar graph kept going out of bounds and I guess it is because it uses that metric to determine it's 5 zones.

 

[psmith]

Funny enough, my last conditioning session my HR went past my 220-age MHR. I was wondering why my Polar graph kept going out of bounds and I guess it is because it uses that metric to determine it's 5 zones.

Well, yes, 220-age is about as accurate as astrology.

My MHR tested from having run as far as I can as fast as I can is about 183.

"As far as I can as fast as I can" could mean a lot of things that wouldn't necessarily elicit a maximum HR. It's possible to work very hard without hitting max HR if various other kinds of fatigue limit effort first. See this discussion from Seiler:

IIRC, Prevost likes a motivated 5k with a fast finish and I've seen recommendations of a fast 400/2min rest/all-out 800 and 2-3 hill repeats on a ~400-800m hill floating around on Letsrun. But, again, the differences probably aren't big enough to really matter, particularly relative to understanding what % of max heart rate your bioenergetic thresholds are actually at.