Everything You Need to Know About Heart Rate Variability (HRV)

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Heart Rate Variability (HRV) is a statistical measurement of the time difference between heartbeats. Most people think that the heart beats at a regular consistent rate. However, that is not the case. The heart rate is inconsistent.

A normal heart rate for an adult ranges between 60 to 100 beats per minute. When you get a reading of your heart rate you may think that the time difference between each heartbeat is the same. But that is not what it means.

The time between successive heartbeats varies irregularly. For example, the time difference between two beats of the heart might be 10 milliseconds and another two beats will vary by 6 milliseconds.

This variation in time between heartbeats is what is referred to as heart rate variability (HRV). And it is measured in milliseconds.

Your HRV varies depending on the situation. Some activities and situations cause the variation to increase hence a high HRV while in other situations the variations remain consistent hence a low HRV.

These variations are very subtle and hence normally undetectable. They can only be detected with specialized equipment.

HRV And The Autonomous Nervous System

The Autonomous Nervous System (ANS) controls the heart rate variability (HRV). Although the heart beats on its rhythm generated by the Sinoatrial node (SA) the ANS has an impact on the heart rate. The SA acts as a natural pacemaker for the heart and controls the heart.

The ANS is divided into two parts, the sympathetic also known as the fight-or-flight system, and the parasympathetic or the relaxation system. These systems are responsible for various activities in the body such as respiration, heart rate, digestion, and blood pressure.

The ANS is the channel through which the hypothalamus transmits signals through the body after processing information. Although the SA controls the heartbeat, the ANS influences the heart rate at a cellular level. The ANS sends different signals to the SA at the cellular level.

The sympathetic system (fight-or-flight) signals the heart to speed up. As a result, the time between heartbeats is reduced hence a lower HRV. The parasympathetic system also known as the rest-and-digest system signals your heart to slow down.  The time between heartbeats is consistent hence a high HRV.

Why Is HRV a Sign of Fitness?

The HRV is an indication of the ability of your body to adapt to different situations. A high HRV shows that your body can process changes, and adapt to the situation. High heart rate variability shows that there is a balance in your nervous system. That is, the body is responding to both the sympathetic and parasympathetic systems and none is dominating.

Research shows that a person in good health should have a high HRV. The HRV is high when the parasympathetic system is dominant. When the sympathetic nervous system is dominant, your HRV is normally low. This usually occurs during exercise.

Low HRV can be a sign of health problems. If the heart rate variability is low and one is not engaged in any strenuous physical activity, it is something worth worrying about. Other factors such as stress, lack of enough sleep, and poor nutrition are some factors that can lead to low HRV.

Therefore, HRV is a measure of fitness. It is a measure of how fast your body can switch from the sympathetic to parasympathetic system and vice versa. From fight to flight to rest-and-digest. When the HRV is high, it is an indication that your body is fit.

What Is a Normal Heart Rate Variability?

It is difficult to say what HRV is normal. What is normal to one person is not the normal value for the other person. Therefore, HRV is highly individualized. And it should be monitored over a period of time to determine what is the normal HRV of a person.

Hence, it is important to monitor your HRV pattern to make sure that you’re fit rather than trying to match another person’s normal.

Source: [https://www.whoop.com/thelocker/member-averages-recovery-strain-sleep-hrv/ ]

According to the graph above, the heart rate variability decreases with age. Elder people have a relatively lower heart rate variability than younger people. The graph further shows that the HPV of women is generally lower than that of men across different age brackets.

Factors That Affect Heart Rate Variability

The heart rate variability varies greatly from one person to another. However, some distinct factors affect HRV. These factors are age, gender, genetics, and fitness level. Some medications and devices such as artificial pacemakers also affect heart rate variability.

Statistics show that the HRV tends to go lower as you age. The average HRV is higher in men than in women of all ages, young, middle-aged, and old. An elite sports person will have a higher HRV than someone who doesn’t train.

HRV is also affected by some conditions such as nutrition, mental and physical stress, sleep, alcohol, and drugs. Unhealthy sleep habits and insufficient sleep can lead to lower HRV. Poor nutrition and dehydration can also lower your HRV.

How To Improve Heart Rate Variability

If you are worried about your HRV numbers, then you will be happy to know that you can improve on that. This is possible by taking care of both your physical and mental health. Here are a few tips on how to improve your HRV:

  • Ensure that you get a healthy diet. And not just a balanced diet but also a regular and well-structured eating pattern.
  • Get sufficient sleep and create a healthy sleep routine. It is good to have a consistent sleeping and waking up time.
  • When it comes to training, don’t overdo it. Don’t overwork your body. It is vital to give your body some time to rest.
  • Work on your mental health. If you are able to manage your stress levels and other mental health conditions, then your HRV will improve.
  • Avoid excessive consumption of alcohol and drugs such as tobacco.

Therefore, if anything is suitable for your general health and well-being, then it will improve your heart rate variability.

HRV Training

Thanks to advancements in technology, we can now do everything smarter than a decade ago. The ability to monitor and record your heart rate variability can influence how you train. This will ensure that your training is effective and you don’t strain your body.

When your heart rate variability is high, this is an indication that your body is fit and you can undertake the intensive routines of your training. When it goes lower, it is time to cut back and take a break.

How To Track Your HRV

Traditionally, the only way you could measure your heart rate variability was by using an ECG. However, today there are specialized devices that can be worn around the body to monitor the HRV.

There are also compatible mobile applications that can be used to monitor and track your HRV. You can also track your HRV by manually logging your HRV data for a period of time.

Contact Us!

If you are looking for a scientific and fact-based training program, contact Marc Dressen.

We will have a training program tailored to suit your athletic or individual goals.

Always remember the popular quote, “mindset is what separates the best from the rest.”

So, work hard, train harder.

I’m Marc Dressen, a high-performance coach, who has worked with elite performers, athletes and entrepreneurs for over 25 years.

I am passionate about unlocking the potential of high achievers - finding that hidden 10% that will take individuals to the next level.

My MSc in Sports Science, coupled with my extensive training in neurolinguistic programming and systemic coaching philosophy has allowed me to incorporate the mind and body into a synergistic machine.

My coaching strategy has now developed into a system that I have coined The Apex Approach, a custom framework that incorporates the latest evidence-based techniques such as biohacking, modern science and digital monitoring, to align the mind and body to its optimum potential. I use biomarkers to remotely coach my clients, so they can receive support whenever they need it.