A healthy heart does not beat like a metronome, but actually changes its rhythm with each heart beat. The constant variation between each beat is called your heart rate variability (HRV). This is something I have been speaking about to several of my patients recently, as more people have smart watches and other health tracker apps that can measure this.
What affects HRV?
There are certain situations that result in a higher HRV and other situations resulting in a lower HRV, reflecting your hearts ability to respond to different situations. This ultimately reflects how your nervous system is responding. HRV can react to stress and/or illness before resting heart rate, which makes it one of your body’s most powerful signals—providing useful insights into your stress levels, recovery status, and general well-being.
Generally a lower HRV is associated with your “flight or flight” response, stress or illness. A higher HRV is associated with your “rest and digest” response, general fitness and good recovery. It is amazing how we can track how just a 5 minutes meditation exercise can improve your HRV.
There are some things we cannot control that affect HRV such as age, hormone cycles, illness and amount of stress we have. However, to improve HRV there are things we can control such as sleep routine, alcohol and caffeine intake, how we manage stress and fitness level.
Tracking HRV
A high or low HRV is relative to each person. It is therefore best to track your own HRV over time and generally aim for a higher level, or track what improves it and decrease it, instead of comparing to others. It can range from 20 to above 150 depending on the tracker. Also, sometimes it is ok to see a lower levels for a short period of time, eg. during a strenuous activity where our nervous system is working hard to increase our heart rate. It is then how we recover that matters.
HRV fluctuates often throughout the day so is is helpful to track it in a controlled setting like sleep. However, some trackers, like the smart watch may limit this if you don’t want to wear it at night.
I see a lot of digestive issues, fatigue, insomnia etc in my practice and it almost always has a component that connects back to the nervous system. If we can help manage our stress response and improve HRV, that can help us tremendously over time. Ultimately, you don’t NEED to track HRV to check in with how you are doing overall. However there are some pretty neat tools out there now that can track things like HRV that we can use to our advantage.
Thoughts? Check in with me if you have questions.
Dr. Karen