What Is Heart Rate Variability and How It's Measured
Have you ever taken your pulse?
It might feel as though your heart is beating at a steady pace, but contrary to the age-old belief, the heart at rest does not beat as regularly as a metronome. In fact, the time between your heartbeats is not consistent; this fluctuation of timing between heartbeats is called heart rate variability (HRV), which serves as a reliable indicator of your body’s recovery status and overall health.
In this article, we discuss how measuring HRV can help inform your fitness regime for maximum results – and how we do it.
What Is HRV?
Your heart changes its rhythm with every beat, and this constant variation in time between each heartbeat is known as HRV.
Picture this: If your heart rate is 60 beats per minute, you may assume that your heart is beating rhythmically every second. The reality is that, in a healthy heart, there’s a slight variability in the time between beats; there might be a 0.9 second gap between some beats and a 1.1 second gap between others.
These variations may be small (adding or subtracting a fraction of a second between beats) but they can indicate current or future health problems, such as heart conditions, mental health issues and, of course, under recovery.
Is HRV the same as an arrhythmia? HRV is a normal occurrence. It isn’t an arrhythmia on its own, which happens when your heart beats out of its usual rhythm.
Why Does HRV Matter?
Keeping a vigilant eye on your HRV can help you ward off injury, illness and overtraining.
As a golden rule of thumb, a high HRV means your body is well recovered. When HRV is diminished for a period of time, it is a good indicator that you may be on the verge of overtraining or, at the very least, tired enough that your ability to respond to training is compromised.
By monitoring your HRV, you can stay informed about your risk of overtraining and your readiness to perform.
How Is HRV Measured?
Reliable HRV analysis requires accurate measurement of each heartbeat and the time between beats. In a medical setting, an electrocardiogram machine (ECG) is considered the gold standard. In an ECG, sensors are attached to the skin of your chest to measure electrical activity of your heart to accurately measure HRV.
Outside of a medical setting, athletes and fitness lovers usually use smartwatches and wristbands to measure their HRV. The downside of this method is that such fitness trackers track your heart rate through the skin of your wrist, which isn’t sensitive enough to detect HRV accurately.
Prevayl offers a better, more accurate alternative. The smart underband in each SmartWear™ garment detects HRV straight from the source – your heart. This gives you the most reliable data that you can use to guide your training whilst minimising the risk of overtraining and injury.
Using HRV With Prevayl
BodyCheck™ is a feature in the Prevayl App which analyses your HRV (in combination with your resting HR) to determine the recovery status of your body.
Compared to the HRV test found in other fitness trackers, BodyCheck™ stands out for its ability to measure your HRV and resting HR in both lying down and standing up phases to identify signs of under recovery and overtraining. Whereas other fitness trackers typically only measure your resting HR and HRV in a lying down phrase, which is only sufficient for detecting under recovery and not overtraining.
It takes only three minutes to perform a BodyCheck™ and it’s best done in the morning when you wake up.
Results from your BodyCheck™ are then fed into a decision tree (which consists of your training frequency, number of rest days taken so far in the week, total number of high-intensity days so far, intensity of training in the previous day, and more) to produce a daily training recommendation on how to approach your training: whether you should train, rest or progress.