What is HRV?

By Joel Jamieson

How is it possible that one number can correlate to risk of developing cardiovascular disease, body fat, athletic performance, and aerobic fitness?

The answer to this question will be discussed over the next 5 days…

Simply put, heart rate variability (HRV) is about providing information to the brain about the external environment so that the brain makes decisions that keep you alive and well.

HRV was first developed in the 1950’s/60’s in the Russian space program to monitor the health of astronauts in space.

To put it simply, HRV is: a non-invasive gauge of autonomic nervous system (ANS) function.

The ANS is divided into two branches:
Sympathetic (fight or flight)
Parasympathetic (rest and digest)

Each branch is responsible for relaying info back to the brain and causing changes in the tissues so that the body can adapt to its environment.

How HRV works: the electrical signals from the brain to the heart are broken down into a pattern and quantified as the amount of time from one beat to the next.

The heart beats in different patterns depending on the influence of the two branches of the ANS.

The greater the influence of the parasympathetic nervous system, the higher the HRV value; the opposite is true for the sympathetic nervous system.

Coming Up Next: The single underlying reason why HRV is such a powerful predictor of health, wellness, and performance.