What is Heart Rate Variability?

What is Heart Rate Variability?

I have to admit that I have been Geeking out lately.

Technology and Testing has given us some amazing tools in the last few years. Part of me wants to know and learn it all and the other half wants to sit in a tree and grow veggies, while I look out over the ocean.  😀.

That being said, a system that measures your heart rate variability has been around for while and has been a very useful tool for many.  Knowing when you are in stress mode and taxing your heart has helps us understand and manage our triggers. Heart Math were the first group that took the idea of measuring the bodies response to stress using a wearable tool.

Apple has recently added this capability to its new Apple Watch.

What is Heart Rate Variability (HRV)?

HRV is regulated by the autonomic nervous system (ANS), and its sympathetic ( stress side ) and parasympathetic ( rest and digest side).

The sympathetic branch of the ANS is the stress or fight or flight system, getting us ready to act, react, and perform – to meet the different demands that life throws at us.

The sympathetic branch activates stress hormone production and increases the heart’s contraction rate and force (cardiac output) and decreases HRV, which is needed during exercise and mentally or physically stressful situations.

The parasympathetic side is characterized as the rest and digest system that allows the body to power down and recover “once the fight is over”.

The parasympathetic branch slows the heart rate and increases HRV to restore homeostasis or balance after the stress passes. This natural interplay between the two systems allows the heart to quickly respond to different situations and needs.

HRV essentially takes the pulse of your nervous system. Another way to think about it is that it’s measuring the impact that stress is having on your overall health and well-being — something that’s normally hard to quantify since lots of adults internalize things rather than acting out.

Why Does Heart Rate Variability Matter?

In a normal, healthy situation, HRV should increase during relaxing activities, for example meditation or sleep, when the parasympathetic nervous system should dominate

On the other hand, HRV naturally decreases during stress, when elevated sympathetic activity helps the body keep up with the demand.

The HRV level changes naturally from day to day, based on the level of activity and amount of, for example, work-related stress, but if a person is chronically stressed or overloaded – physically or mentally

The natural interplay between the two systems can be disrupted, and the body can get stuck in a sympathetically dominant fight state, with low HRV and high stress (cortisol) hormone levels, even when the person is resting.

This is very taxing on the body. Chronic Stress over time results  in various mental and physical health problems.

The good news is that lifestyle has a powerful effect on HRV.  We can take active steps to improve our lifestyle, be physically active and strive for a better balance in our lives, and in the process, will likely see improvements in our HRV as well.

How you can measure your Heart Rate Variability?

This is where wearables and testing can be very effective.  You are able to see in real time what situations effect your nervous system from

  • The food you eat
  • When you eat and how much
  • Hydration and electrolyte balance
  • Your physical endurance
  • The quality of your sleep
  • How you perceive stress and what situations cause you to feel uncomfortable

One of the best resources available is HeartMath Technology

As mentioned earlier the Apple Watch and  associated Apps are available on the new iPhone.

High HRV is generally considered an indicator of a healthy heart, and higher HRV has been found in many studies to be associated with reduced morbidity and mortality and improved psychological well-being and quality of life.

How can you improve your HRV?

 Intelligent Training.

Don’t overdo it and push too hard for too many days without giving your body an opportunity to recover. One training aspect that seems to improve HRV according to many users is sprint training. Try implementing some form of sprint training/conditioning (at a maximum of 2-3 days a week). The sprint sessions need not be long, but hard and fast.


The better hydrated you are, the easier it is for your blood to circulate and deliver oxygen and nutrients to your body. Aiming to drink close to one ounce of water per pound of bodyweight each day is a good goal.

Avoid Alcohol.

One night of drinking may negatively affect your HRV for up to five days.

 A Healthy Diet

Poor nutrition has adverse effects on HRV, as does eating at unexpected times.

Quality Sleep

It’s not just the amount of sleep you get that matters, but also the quality and consistency of your sleep. Going to bed and waking up at similar times each day is beneficial.


In general, trying to get your body on a consistent schedule (in particular with sleep and eating) is helpful. Missing Meals and miss managing your Blood Sugar cause Stress and over time Vascular issues and potential Heart Problems

Practice Focused Deep Breathing

Intentional Breathing slows the Heart Rate and allows our stress response to calm. Do this at least twice a day.

If you have a health challenge and are not sure what is going on and want to know how to connect the dots and get on a plan that is designed just for you  I am available in person or virtually via Zoom

Have a healthy heart week.  The question of the week is Will I get and an Apple Watch ?

Dr Pia