Hello everyone, I would like to know if there are any “norm” values for the DFA Alpha 1 at rest?
I feel like I’m way down…
Thank you for your feedback!
dfa-a1 at rest has no meaning as far as I know. It is a metric related to workout intensity.
It can change a lot, it depends on several factors, there is no standard value at rest.
doesn’t the Polar H10 strap has 4 pads whereas most other straps only have 2 larger ones?
is there a difference at all?
Garmin dual also has 4 pads. The difference is that I now have almost no artifacts. Polar strap was good in the beginning, but signal quality went bad after 7-8 months of use. I had troubles measuring morning HRV and a1 during exercise. Believe me, you don’t want the stress of troubles in the morning…
I’ve been looking out for a place to buy some spare straps, but if you find them, they are usualy expensive. To the point that they cost more then half the price of a complete new strap. So if someone has a lead, I want to hear it.
DFA at rest is a good indicator of how fatigued you may be (there is no standard value), look at the behaviour when you start training, DFA will go down and then it should go up, you have to analyse how that rise is and how long it takes to go up, after chatting with several colleagues we believe that the generation of catecholamines at the start of the training session makes dfa go down (initial stress) and then it recovers, if it takes time to recover we have also observed sympathetic activation. It is also interesting to see the average dfa-a1 in the warm-up and the average in the cool-down (10 minutes in both cases). We are going to put this with the metric we are studying.
I have a Polar H9. Went wonky after about a year. Got it replaced under warranty but the hassle of being without it during warranty replacement was a pain
Somewhere on the forum I have a thread in which you wrote that you use a replacement of the h10 band from the garmin sensor.
I can’t find it now, can you write what band you use?
Me the first h10 band “fell” after five months, I bought a new one (in fact, half the price of the new set), but then I made a complaint and fleece in less than 30 minutes after replacing the e -mail with support, he sent a new band.
Two of my friends also “fall bands” from H10.
Maybe our sweat is somehow more "aggressive?
For my part, I conduct hygiene of the band after each activity.
You can use Polar H10/H9 or alternatively the Garmin HRM Dual with the latest firmware.
Yes strap from Garmin Dual with the Polar H10 sensor on it works very well. I’m cleaning the strap about once a week while in the shower.
Just did a quick 4m ramp to see if my numbers had got back to where they were pre COVID. Considering I jumped on the trainer immediatley after a 7 hour drive I’m quite pleased. Looks like I’m over it. Gentle free warm up until artefacts were <2% and DFAa1 looked OK then 16m @90W followed by 4m steps increasing by 15W. Data points are the average of the last 2 minutes of each step.
Glad to see RR/a1 is being used during tests data analysis.
alphaHRV will provide more functionalities in this field soon
It looks like your maximum upper first threshold range is 151w-132bpm.
Folks
I’ve been reading through this thread (as well as a quick Google). Never heard of AlphaHRV before I saw this…
I think I get what it’s about but can someone please quickly confirm a few things for me to see I’m understanding it.
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This DFA Alpha 1 is a method of using HRV analysis to determine either or both of aerobic and anaerobic thresholds?
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A ramp test is required to be completed (length of which is determined by what threshold you want to estimate).
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Hardware is required. But what hardware apart from my Polar H9 is required? I have a PM also.
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Software also required? Is there an app called AlphaHRV or something? Is this subscription based or one off payment or freeware?
Thanks
DFA (detrended fluctuation analysis) is a time series analysis technique, while alpha1 is a parameter obtained during this analysis.
Applying DFA to heart rate RR-intervals has shown some correlation between alpha1 and the aerobic/anaerobic condition of your activity. There are several works that go deep in this. I recommend you read publications by Bruce Rogers on this subject.
In case you want to determine threshold based on alpha1 ramp test must be used.
There are different platforms and apps that can perform DFA analysis for you.
In all the cases you need to wear a HRM capable of providing good quality RR-int data. Polar H9 or H10 are validated for this purpose.
alphaHRV is a Connect IQ datafield for Garmin devices, so in case you want to use it, you need a compatible Garmin device. A lot of devices are supported, although high performance watches or cyclocomputers are strongly recommended because the app is high demanding in terms of computation.
You can download alphaHRV from Garmin Connect IQ store. It stays in beta phase now and it’s free.
Yes, getting the data is one thing, interpreting it is something else again. Alan Couzen’s take on this is that the point at the first inflection is your Aerobic Threshold ie from above 127bpm/136W.
He then calls Z2 as his Steady Endurance as a workable range above that ie +10bpm and +20/25W. Inigo San Milan on a recent tweet confirmed that this coincided with his Z2, They use lactate of course, AC also has an Easy Endurance range of AeT to -10bpm/-25W. My inclination is to be cautious and agree with your assessment of my upper limit of 132bpm/151W though.
I use the AlphaHRV garmin app on my Edge 1030. I set 2min intervals on the Garmin. I use Xert as my way of performing the step test, and simultaneously record to the Garmin. After the workout has been saved to Intervals.icu I download the Intervals Data to Google sheets and then manipulate it to get the graph above. I might add that I’m retired and have lots of time to do this.
Is the ramp somehow defined? Or can I just run my Garmin alongside Wahoo X when I do the “Half Monty” Ramp Test? I’m already running Wahoo X on the iPad and the ROAM V2 to control the Kickr Core (iPad is too far away ) so a third device won’t matter too much
IMHO currently dfa cannot be used to set thresholds, with the covid pandemic and in quite a few cases I have those values have changed, but it can be used for other things, which we will explain soon.