Meditation, relaxation, binaural beats, are good to help raise my HRV ( that, I have measured with my Freeze-Framer)... no surprise that those tools has been part of my overall approach in reducing the severity and duration of my POIS.
To raise ? or to decrease ?
Hi b_jim,
Short answer: what you want is to raise your HRV. Following are more details.
Heart rate variability (HRV) is a very interesting measurement. It is different form the heart rate. HRV is the subtle variation in your heart rhythm, cyclically, over a short period of time, like during a breathing cycle. One of the main cause of HRV is what is called the respiratory sinus arrhythmia. In lay terms, that means that your heart rate slightly speeds up during inspiration, and slightly slows down during expiration. That's because when you inhale, it lowers the vagal tone influence on the heart, and when you exhale, the vagal tone influence on the heart is heightened, so the heart slows down a bit.
A high HRV means you have pronounced speeding up and slowing down of your heart rhythm. A lower HRV means you heart keeps more or less the same rhythm, not really as mechanical as a clock, but have less variation in rate than expected values.
A reduced HRV is associated with heart problem, with depression, with PTSD, high anxiety, and other problems. It even has been shown to be a predictor of mortality after myocardial infarction.
A high HRV is associated with peak performance, with feeling in the zone, with optimal vagal tone, and with balance between sympathetic and parasympathetic systems. Here is how the Hearthmath institute puts it: "Numerous studies show HRV is a key indicator of physiological resiliency and behavioral flexibility, and can reflect an ability to adapt effectively to stress and environmental demands." (
https://www.heartmath.org/articles-of-the-heart/the-math-of-heartmath/heart-rate-variability/ ).
So, to answer your question,
what is desirable is to raise Heart Rate Variability ( HRV ). The fact that in POIS acute phase, HRV is lowered, it clearly shows that the balance between vagal tone and sympathetic tone is disrupted. We all, POIS sufferers, know for a fact that during POIS acute phase, we are litterally out of whack, don't we?. This lower HRV shows it in a measurable way, the Rutgers study tells us.
For anyone interested in more in-depth information about HRV, see
https://en.wikipedia.org/wiki/Heart_rate_variability and
https://www.heartmath.org/articles-of-the-heart/the-math-of-heartmath/heart-rate-variability/ .