Heart Rate Variability: What HRV Is and Why It Matters

Let me ask you something. When was the last time you made a real effort to relax your mind and body? Last week? Last month? If your honest answer is “I’m not sure,” you’re not alone. Most of the people I coach in Austin are running on full speed most days.

One way people have started paying attention to stress and recovery is a number called heart rate variability, or HRV. Your smartwatch or ring might already show it. I first wrote about HRV on our old blog in 2017, and since then it’s gone from a niche athlete thing to something on millions of wrists. So let’s talk about what it actually is.

An important note: I’m a coach and Nutritionist, not a doctor. This post is about what HRV is and lifestyle habits. If you have questions about your heart or what your own numbers mean, please talk to your doctor.

What is heart rate variability?

Your heart rate is how many times your heart beats per minute. Say it’s 60. That doesn’t mean your heart beats exactly once every second like a metronome. The time between each beat changes a little, maybe 0.95 seconds, then 1.05, then 0.98.

That small change from beat to beat is heart rate variability. It’s measured in milliseconds, and it’s usually shown as a single number in your app.

Your two nervous system modes

Your body has an automatic nervous system that runs things you don’t think about, like breathing and digestion. It has two main modes:

• Fight-or-flight (sympathetic). This is your gas pedal. It kicks in during a hard workout, a stressful meeting or a near miss in traffic.
• Rest-and-digest (parasympathetic). This is your brake. It’s in charge when you’re relaxed, eating a calm meal or falling asleep.

A healthy body needs both, and it needs to be able to switch between them easily. HRV is one window into that balance. In general, when you’re relaxed and recovered, the variability between beats tends to be higher. When you’re stressed, tired or worn down, it tends to be lower.

I like to think of it like a good dancer. A stiff dancer moves the same way no matter what the music does. A relaxed dancer adjusts to every change in the song. A heart that adjusts beat to beat is a bit like that relaxed dancer.

Why people track HRV

Many athletes check their HRV first thing in the morning. If it’s much lower than their usual, they may take an easier day. Over time, they learn what helps them recover and what wears them down.

You don’t have to be an athlete to find this interesting. Some people use it to notice how a late night, a big dinner or a stressful week shows up in their body.

My honest take: HRV is one data point, not a grade. It changes a lot from person to person and day to day, so comparing your number to a friend’s isn’t useful. The trend over weeks is what tells you something. And the research on what HRV means for health is still developing, so I don’t want anyone reading too much into a single morning.

How people measure it

Most people use a wearable: a watch, a ring or a chest strap. Wear it consistently, especially overnight, for a few weeks so the app can learn your baseline. Measure at the same time each day, ideally in the morning before coffee and your phone.

Everyday habits that support recovery

This is the part I care about most, because it’s the part you can actually do something about. These are the habits that support rest and recovery in general:

• Sleep. A regular bedtime and wake time is one of the biggest things you can do for how you feel.
• Movement, with rest days. Exercise is great, and recovery days are part of the plan, not a sign of weakness.
• Real food at regular times. Meals built around vegetables, protein and healthy fats, without long stretches of skipping food.
• Water. Being low on fluids can leave you feeling tired.
• Slow breathing. A few minutes of slow, relaxed breathing is a simple way to tap the brake.
• Less alcohol, especially at night. Many people notice they sleep better without it.
• Time outside and time with people you like. These count as recovery too.

Game plan

1. If you already have a wearable, look at your HRV trend for the past month, not just today.
2. Pick one habit from the list above and do it for two weeks.
3. Notice how you feel, with or without the number.

You can also try our free tools at tools.austinholisticfitness.com, or read how stress and weight gain are connected.

Want a simple place to start?

If you’d like a week of easy habits around food, water and rest, our $27 7-Day Reset is a gentle first step. For more support, there’s the 8-Week Program.

Do you track your HRV? Tell me what you’ve noticed in the comments.