You may have seen or heard references to the term “heart rate variability” and that it’s a way of assessing one’s heart health. But you’re probably wondering what it is, how you can measure it and what it implies for your health and lifestyle. Let’s explore all of this and more.

Heart rate variability (HRV) is the variation in time intervals between successive heartbeats. In other words, it’s the changes in the time gap between one heartbeat and the next. Let’s use an example. Say your heart rate is 60 beats per minute. That doesn’t mean your heart is necessarily beating exactly once every second. The time between each beat can vary slightly. The difference in the time between each beat is called heart rate variability. 

Why Does Heart Rate Variability Matter?

HRV is an important measure of the activity of your autonomic nervous system, particularly the balance between the sympathetic and parasympathetic branches. The autonomic nervous system is the part of the peripheral nervous system that controls involuntary processes in our body, like heart rate, digestion, and respiratory rate. Here’s how it works:

1. Sympathetic Nervous System (SNS): This is often called the “fight or flight” system. When you’re stressed or faced with a threat, your SNS gets activated, leading to increased heart rate and readiness for action.

2. Parasympathetic Nervous System (PNS): This is known as the “rest and digest” system. It helps you relax, recover, and conserve energy. When you’re at ease and feeling safe, the PNS dominates, leading to a slower heart rate and improved digestion.

Both branches are continuously active, but their balance shifts based on your current state, emotions, and environment. This is where heart rate variability comes into play.

High vs Low Heart Rate Variability

Higher HRV is generally considered a sign of good heart health and better adaptability to stress. When your heart rate varies more between beats, it indicates a higher parasympathetic tone and a flexible and responsive autonomic nervous system. This means your body can quickly switch between being alert and being calm, depending on the situation. This adaptability is essential for maintaining overall health and resilience.

On the other hand, lower HRV is associated with a lower parasympathetic tone, which correlates with various health issues and increased stress levels. Reduced HRV may be linked to chronic stress, anxiety, and certain heart conditions.

How and Why to Monitor Your Heart Rate Variability

Monitoring heart rate variability can offer valuable insights into your overall well-being, stress levels, and cardiovascular health. In a medical setting, HRV is measured using an EKG, but these days there are numerous trackers available for personal use. Measuring and monitoring your heart rate variability over time is a useful way to receive feedback on your body’s response to different situations and activities.

Photo by Ketut Subiyanto

So, the next time you hear about heart rate variability, remember that it’s all about the beautiful dance between your sympathetic and parasympathetic nervous systems – keeping your heart adaptable, healthy, and in tune with your emotions and environment. And if your measurements indicate that your heart rate variability is reduced or is lowering over time, consult a medical professional to help you devise strategies to improve your baseline and optimise your HRV.