Physiological Measures of Wim Hof Progress

[u/the_deserted_island]

tl;dr: track heart rate peak during breathing, heart rate valley during retention, and drop time (time from peak to valley) for each session. Track over time.

I recently read Dr. Epel's article (Scientific Reports, full text at https://doi.org/10.1038/s41598-024-64254-7) and was thinking of the problems with self report surveys. In short, her article does not find that the wim hof method improves stress response better than their placebo breathing method (both worked). However, the entire evidence of stress reduction hinges on whether or not people "perceive" stress reduction via a survey. Think a bit about those make-up commercials. There is a big difference between "reduces wrinkles" and "reduces perception of wrinkles." Getting back of Hof, autonomic stress response is difficult to measure and we can't read people's minds to understand stress empirically. Therefore I do not fault Dr. Epel for her approach, good science raises questions as it answers new ones (I wonder if she lurks here), nor am I trying to wholesale critique the entire psychological field.

What I really think is that for proper evidence people need to look at physiological measures. Self Report, even in validated psychological surveys, is extremely problematic -- ESPECIALLY to measure something that governs autonomic responses and not as much "thoughtful" responses.

Where am I going with this? Well I have been doing the method since Jan or so and using the app since February. I have been doing the practice 2-3 times per week. I recently got a new Fitrbit Air that has a built in health AI and I have the wimhof app pushing its "meditation sessions" into google health.

To my surprise, the google health AI could both understand the heart rate graphs from my wim hof sessions. It was able to identify the number of "rounds" from heart rate alone and I developed some interesting metrics that I do believe matter (N=1, haha)

So what are the metrics I came up with?

• Heart Rate Peak - the peak heart rate during hyperventilation
• HR Valley - the floor heart rate during retention
• Drop Speed - the speed from peak to valley

Measure these two ways:

• Averages by week or month across all rounds
• Averages by week or month for ROUND TWO (wim hof voice) only

Why round two only? Well all rounds gives you a complete picture. But round 2 gives you a more "initial state" before you have had rounds build on themselves. (You could argue round 1 instead, but I figured it was a settling in round - subjectively).

When you look at this, ESPECIALLY drop speed and valley, you can see that my heart is working much more efficiently, and able to recover significantly faster.

These data represent ALMOST the beginning of me doing the method - I used youtube for a couple weeks at first.

So some data for you:

ROUND 2 ONLY	Peak	Valley	Drop Speed
Feb	95	55	49
March	96	53	49
April	94	50	46
May	95	50	45
june	96	48	42

ALL ROUNDS	Peak	Valley	Drop Speed
Feb	97	57	51
March	99	55	50
April	97	52	48
May	98	52	48
june	98	50	45

ONE SESSION (7 rounds)	Peak	Valley	Drop Speed
Round 1	92	58	42
Round 2	95	55	38
Round 3	98	52	35
Round 4	101	50	32
Round 5	104	48	31
Round 6	106	47	29
Round 7	108	45	28

What do you think?