Heart Rate Variability (HRV) is one of those training tools that is too simple not to use: all you need is a compatible heart rate strap, a smartphone, a free app and 1-3 minutes every morning while you are drinking your coffee.

I have been tracking my HRV every morning for years. I don’t geek out on all the data like I could, but I have still learned a lot. Now I I trust it more and ignore it less.

What is HRV? This is my non-scientific Cliff Notes version but I’ve added a few links at the bottom for those of you with enquiring minds. HRV is simply measuring the variability of the time between each beat of your heart. The time between beats is controlled by – and is an indication of – the balance between your sympathetic (stressed: fight or flight) and parasympathetic (relaxed: rest and digest) nervous systems. A higher HRV (more variability) is good. A more balanced sympathetic / parasympathetic ratio is good.

For an athlete, HRV can be one tool to assess if you are in a state of good recovery, normal training stress, or edging into overly stressed and possibly over-trained.

Not an athlete? Don’t think you get a free pass. All stress affects our bodies and our health. You may not think of it as overtraining, but prolonged stress can cause you to crash and burn too.

It is important to know that HRV varies by person. What is an average number for me is different than what is an average number for you. By tracking your HRV daily your chosen app will learn what is average for you (and hopefully you will too).

So how do you measure your HRV and how do you use it?

Get the tools:

  • An HRV app: I have always used the free SweetBeat HRV app from SweetWater Health. Over the next couple of weeks I will test out two other free apps: ithlete and Elite HRV. I will let you know how I think they all compare. If any of you are using other apps, please let me know what you think.
  • A compatible heart rate monitor strap. All of these apps have websites that guide you to which HR monitors will work. I use the Wahoo Tickr Bluetooth. Just make sure you choose one that is compatible with your app.
  • A few minutes each morning. It is important to take the measurements the same general time each day. You should be seated and calm while taking the measurements. Drink your coffee. Take some deep breaths.


Analyze the reading: The app will give you your HRV reading for that morning. The SweetBeat app also tells me my average heart rate and my LF/HF (or sympathetic / parasympathetic) ratio. It will also tell me exactly what it thinks, whether I want to hear it or not. My HRV has dropped significantly – it thinks I should do an easy workout. My HRV has dropped two or more days in a row – it thinks I should rest. My HRV looks good – it thinks I should go kick butt…


Understand that this is one tool. You should not assume any one tool is THE ANSWER. You need to be in touch with how you are feeling, how much you have been training, how stressed you are, etc. You still need to listen to your coach; by the way, HRV is a great number to share with your coach via your training portal.

Following the HRV app advice…


I have days when I disagree with my HRV reading. But I have to admit, it is usually right. There have been days when it tells me I really need to rest and I ignore it, only to find myself giving up on the workout because I have no gas in the tank. There have been other days – today was a great example – where I wake up feeling hammered but my HRV is great. Damn it, I just want to go back to bed. But often on those days I end up having a great workout. Today I felt amazing once I got moving.

When I taper well for a race, my HRV hits its highest readings in the days before the race. Talk about a psychological boost!

I think if you pay attention not just to the daily readings but also to the trend, you can learn a lot. And what do you have to lose? It’s cheap, it’s easy and it just might teach you some things about your body and your training.

Here are a couple resources (there are many others too) if you thought my two-sentence explanation was unsatisfying: