Fitness Wearables: The Truth About the Data

Fitness Wearables: The Truth About the Data

Ranging from watches to rings, fitness wearables are all the rage among those seeking health and performance. It’s common to hear users of these devices discussing their “readiness” and their sleep scores.

To the untrained ear, this may sound like gibberish, but these companies promise that the data their devices provide can help users train, sleep, eat, and live better.

Are these devices worth the investment or are they just flashy techno jewelry? This article will answer that question, as well as explaining how fitness wearables work, the data they provide, and two popular options.  

What are Fitness Wearables

Fitness wearables are devices you can attach to your body that measure biometrics including your resting heart rate, heart rate variability, sleep, and activity levels. These products collect this data then run it through their algorithms to provide you with multiple health metrics. 

Companies promise that these metrics will lead to a host of benefits including better sleep, performance, and vitality. However, before examining their benefits it’s important to understand how these devices work.

How Fitness Wearables Work

Most fitness wearables use three data points to track your health and fitness: resting heart rate, heart rate variability, and activity level.

Resting Heart Rate (RHR) 

Resting heart rate is the number of heartbeats per minute your body performs while at rest. RHR is a useful metric for measuring overall fitness, daily readiness, and recovery.

Fitness wearables measure RHR by counting the users’ heartbeats per minute. A lower resting heart rate has been correlated with increased heart health.

A great way to lower resting heart rate is to train the aerobic system. Learn more about aerobic training here.

Heart Rate Variability (HRV) 

Heart rate variability is the measure of the variation in time between each heartbeat. It is controlled directly by the autonomic nervous system, the same system that controls the body’s fight or flight response.

To calculate HRV fitness wearables look at the difference in time between heartbeats.

HRV is useful because it provides insight into the health of your nervous system. A higher HRV is correlated with a more resilient nervous system, while a lower HRV is correlated with less resiliency. 

Activity Level

Activity level measures physical activity throughout the day. This can give insight into health patterns and behaviors.

This metric can be measured by using a simple chronometer to track steps or with a combination of heart rate and movement. Depending on the device this measurement can be quite subjective.

Daily movement outside of the gym is one of the best ways to support recovery and overall health. Learn the basic guidelines for a healthy lifestyle here.

The Data Fitness Wearables Provide

Each brand of fitness wearable has its proprietary metrics and formulas for displaying and calculating your health data. Commonly, these devices display your readiness, activity, and sleep score. 


Readiness refers to how prepared your body is to perform on a given day. 

To calculate this metric, most fitness wearables look at a combination of your RHR and HRV. They take into account your activity the day prior, how well you recovered during the night, and then create a readiness score for the next day.

As a general rule of thumb the higher your HRV and the lower your RHR, the more prepared the body is to take on stress.

Activity Levels

Using a combination of movement and heart rate, these devices assess your daily activity levels. This metric gives you insight into how active you have been and will make a suggestion to either rest or increase your activity levels.

The activity level is also taken into account when calculating your readiness and sleep score. 

Looking to increase your activity level? Learn the seven fundamental movement patterns for exercise in this blog.

Sleep Score

The final metric these devices calculate is your sleep score.

During the night these devices track your heart rate to monitor your duration and progress through sleep cycles. Each morning these devices provide you with a score of how well you slept.

This score is calculated with time asleep, RHR, and movement throughout the night. This score directly affects your readiness for the day. 

No matter if you sleep a sound 8 hours a night or struggle to get 3, there is no denying that for optimal health you need quality sleep. Learn 6 tips to get better sleep here.

Two Popular Fitness Wearables

Two popular fitness wearables are the Whoop Band and the Oura Ring. These two products are leading the progression of what wearable fitness technology looks like.

The Whoop Band is a watch style product that measures your sleep, recovery, and daily strain. 

The Oura Ring boasts that it is the most accurate fitness tracker on the market because of its location on the finger. It measures your sleep, activity, and readiness.

Both of these products use a formula of RHR, HRV, and activity to calculate their metrics.

Are Fitness Wearables Worth the Investment?

Deciding whether or not to invest in a fitness wearable comes down to what you will use it for.

If you are looking just for data and are capable of making your own decisions whether to train harder, take a day off, get more sleep, etc., then it can be a worthwhile tool.

However, if you are hoping that this data will inherently make you fitter you are better off seeking out a fitness professional, like an OPEX Coach, who can create a workout and lifestyle program specifically for your needs.

Do you love health and fitness? Do you like to share the latest exercise and nutrition knowledge with those close to you? If you answered yes to any of these questions then a career as a fitness coach could be right for you. Sign up for our free coaching course today and learn how you can create a successful and sustainable career as a fitness coach.


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