How to Understand Your HRV, VO2 Max, and RHR Insights

Thanks to its tracking and measuring capabilities, your Atlas Wearables watch offers you a wealth of data that you can use to continue to improve your health and fitness. Three of these metrics are: 

  1. Heart rate variability (HRV)
  2. VO2 max
  3. Resting heart rate (HRH)

Let's talk about each of these individually and how you can interpret them

Heart Rate Variability

We've talked about heart rate variability before and how it relates to recovery. It's completely normal and healthy for your heart to beat in irregular patterns. It's not a perfectly steady rhythm. The time between individual beats changes. 

This is because your body's parasympathetic and sympathetic systems are sending competing messages to your brain, the former telling your heart to slow down and the latter telling it to speed up.

This is why our heart rate fluctuates. 

Now, there's more than one way to measure HRV. These include:

  • RMSSD (root mean square of the successive differences).
  • SDNN (standard deviation of the NN).
  • PNN50 (the proportion of NN50 divided by the total number of NN).

Various fitness wearables have experimented with these differing metrics.

However, RMSSD is now widely considered the best measurement. RMSSD is able to quickly capture fluctuations due to changes in the heart rhythm. It's also easier to measure and compute with, and it's a reliable measurement even when we're dealing with short timeframes and less controlled conditions.

For these reasons, RMSSD will reflect changes that happen in response to all kinds of triggers of stress, not just training. We're also talking about travel, drinking, and even illness, which can absolutely have an effect on your training, recovery, and health in general.

We received many requests for HRV tracking and want to provide you with the most thorough and accurate data possible. So, you can now find it if you tap Log > Graph Data > RMSSD. 



graph data




So, how can you interpret the RMSSD measurements that your Atlas watch gives you? 

We want to preface this by saying that there are numerous factors that affect your HRV. These include, among others: 

  • Age
  • Stress
  • Activity level
  • Hormones
  • Breathing
  • Metabolism
  • Posture

So, don't make the assumption that your RMSSD changes solely due to your training/fitness.

Because of all of these factors, it's challenging to pinpoint a "normal" HRV, since it's highly individualized. Rather, heart rate variability trends are what matter.

Thus, you might consider comparing your Atlas RMSSD readings over time. Generally speaking, a higher HRV score is an indicator of good health. However, since we know that it's difficult to define "higher," instead, look for increases in your RMSSD over time and workouts. 

This could indicate improvements in heart health and aerobic fitness. It means that your body is better adapting to handling stress. You can see these improvements even while you're sleeping.

Likewise, you can use this data to help plan your workouts. 

For example, if you're noticing that your HRV scores are higher than usual, this is a good time to push hard at the gym. Your body is in a great place to handle that stress. 

On the flip side, if your HRV scores are dipping, it might be a good time to take a rest day. Your body might not currently be in a good place to handle too much physical stress in the gym. 

Takeaway: Aim to increase your RMSSD over time. Monitor these readings to develop your programming. Higher HRV scores indicate good conditions for tougher training. Lower HRV scores indicate good conditions for rest.

VO2 Max

You'll find your VO2 max data if you tap Log > Graph Data > VO2 Max.

VO2 max


Your VO2 max is the maximum amount of oxygen you can utilize when you’re working out. It's measured in milliliters of oxygen used in one minute per kilogram of body weight — "ml/kg/min."

Here's an example. 

VO2 max


As with your HRV, it's important to first know that your VO2 is affected by numerous factors. These include:

  • Age
  • Gender
  • Altitude

Keeping this in mind, some research says that the average male has a VO2 max about roughly 35-40 mL/kg/min, and the average female, 27-30 mL/kg/min.

Knowing and understanding VO2 max is important because it can reveal so much about your fitness capacity — like how long you can maintain a certain intensity of exercise.

Here's how you can interpret this data. 

Once again, we encourage you to look at patterns over time, as opposed to one isolated data point. In general, when you have a higher VO2 max, this means that your body is better able to take in oxygen and send it to your muscles. This, in turn, means that you have better endurance. 

Thus, over time, you ideally want to see increases in the VO2 max numbers that your Atlas watch is tracking. 

In terms of your training, one way to improve this metric is by incorporating more high-intensity interval training. This will push your body's anaerobic threshold and train your body to better take in and distribute oxygen.

It's more than worth noting that regardless of where you're currently at in your fitness journey or what your goals are, you should care about your VO2 max. Even if you're a very casual athlete, improvements in this number can lead to reduced levels of stress and more ease getting through your daily tasks. 

We're talking about things like climbing a flight of stairs or bringing the groceries in — two things that leave many of us winded, if we're being honest with ourselves.

Resting Heart Rate 

Under Graph Data in your Atlas Wearables app, you'll also find Resting Heart Rate.

resting heart rate


The Mayo Clinic says that a normal RHR for adults can range anywhere from 60 to 100 beats per minute. At your resting heart rate, your heart is pumping the least amount of blood that you'll need since you're not exercising.

Once again, we remind you that various factors impact this number, including: 

  • Age
  • Temperature
  • Body position
  • Medication
  • Body size

However, in general, a lower RHR can indicate better cardiovascular health, because your heart doesn't have to work as hard when your body is simply at rest. This is why athletes and people who are generally more active might have a lower RHR — as low as 40 beats per minute. 

If you are consistently minding your fitness and nutrition, then you can likely expect to see a downward trend on this graph, which means that your HRH is decreasing — a good thing!

Is the opposite happening? Something might be off. Talk to a fitness or medical professional to see if you might be doing something that stresses your body out and keeps it in that state. 

It's worth pointing out that you might track your RHR specifically in relation to fitness journey, remember, too, that it's a good indicator of your overall heart health. As Harvard Health Publishing notes, people with a lower RHR are at a decreased risk of heart attack, cardiovascular disease, and even early death.