Taking care of your physical and fitness health is a priority for many people. With the recent advent of wearable health and fitness technology, it has never been easier to monitor your progress. We all know the importance of monitoring our heart rate, sleep cycle, and breathing rate, but measuring heart rate variability (HRV) doesn’t have an apparent reason. You might be wondering why you should be measuring your HRV, what a “good” HRV number is, and if you can improve it. Let’s take a look.
What is HRV?
HRV refers to the variation in the time between consecutive heartbeats, measured in milliseconds. Your heartbeat isn’t entirely even, but you won’t be aware of the variability in the time difference most of the time. It isn’t obvious in the same way that an increase or decrease in heart rate is, and your HRV will vary throughout the day.
Why is HRV important?
Your HRV is a good measure of your overall physical and mental health. Your HRV is regulated by your autonomic nervous system (ANS), which is the system that controls your fight-or-flight response in reaction to stress (the sympathetic branch) and your rest and digest system for recovery (parasympathetic branch). When your sympathetic stress system is dominating, your HRV will be low, but when your parasympathetic system is dominating, and you’re relaxed, your HRV will be higher.
Your HRV number will also be influenced by your overall heart health, with higher HRV numbers associated with a greater level of heart health and fitness and a lower level of disease, morbidity, and mortality. It is also influenced by your hormonal reactions, metabolic processes, your cognitive processes, and of course, your stress levels.
What is a good Heart Rate Variability?
If you have never measured your HRV before, you will likely want to know if yours will be classed as low or high, but it isn’t as simple as reading a number of a table to find this information out. Unlike many other health metrics, HRV is personalized to the individual. Around 30% of your HRV is due to genetic factors, with the rest being influenced by lifestyle factors. So, in reality, comparing your HRV number against other people’s can be completely meaningless.
Instead, the best way to improve your HRV and/or monitor your mental and physical health using this metric is by examining your trends. Over time, you will be able to see if your HRV is getting bigger or smaller on average, and this will tell you whether you are improving your health through any lifestyle changes you are making.
How can I measure my HRV?
Of course, to measure your HRV trends, you are going to need a way of measuring them in the first place. And, because your HRV number will fluctuate throughout the day, the most accurate trends will come from continuous monitoring. Thankfully, there are devices available that can do just that.
These devices work by using photoplethysmography (PPG), a method of optical heart rate monitoring. PPG works by shining a light through your skin, usually through a worn device on the wrist. The amount of light scattered by the blood flow will behave in predictably different ways depending on how strong the flow of blood is, which allows this method to detect heartbeats. The device will then measure the time between the heartbeats to give you your HRV trend.
The Fitbit 5 will measure your HRV alongside a range of other health factors, such as heart rate and Sp02. And you will be able to monitor your HRV trends and see how they change over time in relation to your overall fitness. The Whoop 4 also measures HRV and incorporates it into its Recovery metrics as an indicator of your overall health as well as your training adaptation.
How do I increase my HRV?
We know that the higher your relative HRV, the better your overall health. It is a good indicator of how well your heart is working, your overall fitness level, and psychological health factors such as stress. So if you want to improve your HRV number, these are the issues to focus on.
The most important is increasing the amount of physical activity you participate in, particularly physical activity that improves your cardiovascular health. These types of exercise, also known as aerobic exercise, increase both your heart rate and your breathing rate. So any activity that gets you moving and makes you breathe faster will be helping to improve your heart health and your HRV, and this can be anything from a brisk walk to Zumba fitness or a spin class.
Another way of increasing your HRV is to lower your stress levels. Chronic stress isn’t just unpleasant to experience. It also can have severe and even life-threatening consequences. These can include an increased risk of diabetes, cardiovascular disease, stroke, and certain cancers. Lowering stress levels can be challenging, especially if you have a lot of pressure in your life. Some people find meditation/mindfulness to be valuable tools for relaxing.
Physical exercise is again a great way of lowering stress, so it can help to improve your health and your HRV in two different ways. Making sure that you get enough sleep (between 7 and 9 hours per night on average) and that your sleep quality is good can also help lower your stress levels, and you can monitor this using the same device that is measuring your HRV.
To wrap up
Your heart rate variability is an essential indicator of your physical and mental health, including your heart health and your stress levels. Your HRV changes throughout the day, but an average higher HRV is associated with good health.
However, this number isn’t something that can be compared between people, so you need to look at the changes in your HRV over time. This can be achieved by using a wearable fitness device that records your HRV, and you can then use this information to help you improve your health with lifestyle and exercise changes.