Effects of warm water immersion on blood pressure, heart rate and heart rate variability in CFS

[Pyrrhus]

There was a significant difference between groups in HRV prior to immersion (control group: 73 [55–74] vs. chronic fatigue syndrome group: 63 [50–70]; p = 0.04). There was no difference in HRV post-immersion.

As a reminder, heart-rate variability (HRV) is used to give a rough idea of the functioning of the autonomic nervous system. Low HRV is generally seen during activation of the sympathetic nervous system or during any other activity that raises the heart rate. High HRV is generally seen during activation of the parasympathetic system or during any period of rest.

Measuring HRV is often used by ME patients because patients demonstrate unusually low HRV during rest, when healthy people would show high HRV.

 

[Jjnz]

Healthy or recovered from exercise people show high Hrv during rest,
High Hrv is parasympathetic, relaxed
low Hrv is sympathetic, stressed
I'm actually surprised the cfs vs control group is so close in Hrv, if measured in ms. Even 4 years ago, at my fittest, my Hrv was 20~25ms, about 0~5ms when exercising. I don't think I've ever seen anything like 60ms.
Another factor might be water temp, whilst elevated it may be parasympathetic and relaxing, which is why everyone wants to pee when we enter a warm pool

 

[Abrin]

This thread totally reminds me that now that it is winter where I am again that I should start trying to do once a week saunas again to see how they go.

 

[Pyrrhus]

A key figure from the paper: