Can Your Fitness Tracker Help Warn That You Have COVID-19?July 2, 2020 - Katie McCallum
Think about the number of hours you wear your smartwatch or fitness tracker every day. It's probably a lot — if not every hour that surrounds the 30 minutes or so it needs to charge.
The amount of time you wear your device, combined with the amount of information your device is built to collect, results in the accumulation of a lot of data about you. In fact, the average wearable device collects 250,000 measurements every single day — all of which is processed through powerful algorithms and presented to you through visually appealing apps and interfaces.
As a result, you can use your fitness tracker to monitor the quality of your sleep, performance of your workouts, calories burned throughout the day or just to remind yourself to get up and get moving.
But, is that device strapped to your wrist powerful enough to help warn you that you may have COVID-19?
What we already know about predicting infection through fitness trackers
One of the most important measurements your fitness tracker takes throughout the day is your heart rate.
Your heart rate is the number of times your heart beats per minute, and a healthy heart rate means a healthy you. Heart rate varies not only from person-to-person, but throughout the day for each individual. Since your wearable device continuously tracks your heart rate throughout the day, it eventually comes to learn your average heart rate — creating a baseline representing what's normal for you. This means that your fitness tracker can also identify when your heart rate fluctuates from its baseline.
Most of the time, heart rate fluctuations are a natural part of your day — a response to sleep (in which your heart rate lowers) or activity (in which your heart rate increases). In fact, your device relies on these heart rate fluctuations to help determine how well you slept or how hard you worked during an exercise.
But, unexplained fluctuations in your heart rate could signal a variety of health issues, including an infection.
In fact, a recent study examining 200,000 Fitbit users found that changes in resting heart rate and other sleep measures could predict seasonal flu rates in real time at a statewide level. While the purpose of this study was to determine if fitness tracker data could help public health officials detect and respond to seasonal flu outbreaks sooner, the findings suggest a connection between flu-like symptoms and the heart rate fluctuations detectable by a person's wearable device. This means that, in the future, fitness trackers could potentially help detect seasonal flu at the individual level, too.
So, what we do know about wearables and predicting COVID-19? Overall, not much yet — but we're definitely learning.
What we're learning about fitness trackers and COVID-19 detection
The number of studies currently examining whether wearable devices can help signal infection with coronavirus grow by the day.
For Fitbit users, participating in these studies is as easy as joining via your Fitbit app or online.
Other studies, like Scripps Research's DETECT Health Study and Duke's COVIDENTIFY Study, are also testing whether your smartphone, Apple Watch, Fitbit or Garmin can help predict and detect COVID-19 hot spots, and maybe even help you determine if you're getting sick yourself.
There's also the Oura "smart-tech ring," which is currently being studied to determine if the health care workers and other volunteers wearing these rings can detect COVID-19 before symptoms develop. Even NBA players are planning to give these smart rings a try.
With all of this research, there's hope that the devices many of us wears every day may eventually be able to help prevent the spread of COVID-19 sometime in the future — but for now, the jury is (mostly) still out.
A promising lead may be emerging
When it comes to detecting COVID-19, there is one particular fitness band, called WHOOP, that may already be showing promising results. This particular wearable uses raw heart rate data to track a person's respiratory rate during sleep — and WHOOP claims to currently be the only wearable device that accurately measures respiratory rate, as validated by a third-party clinical trial.
A recent study, cooperatively performed by WHOOP and Central Queensland University researchers, found that the respiratory rate changes detectable by the band may be able to both predict and detect COVID-19. Of the 81 COVID-19 positive individuals included in this study, WHOOP data and models were shown to be capable of detecting:
- 80% of COVID-19 cases by the third day of symptoms
- 20% of COVID-19 cases two days before the onset of symptoms
Detecting COVID-19 three days after symptom onset may not seem like a huge deal, but predicting COVID-19 before symptoms occur — even if in only one-fifth of pre-symptomatic individuals — may be significant given that public health officials continue to warn that pre-symptomatic individuals can be contagious.
One factor about this study that's important to note, however, is that the WHOOP study is still in pre-print and under peer review — a process by which a panel of independent, unbiased researchers review and analyze the scientific underpinnings of the study. In the meantime, however, individual accounts of the power of the WHOOP band continue to hit the news — including PGA Tour player Nick Watney's COVID-19 story, in which it's claimed that his WHOOP band was "key in detecting his positive test."
For now, though, stick to what we know works
At the end of the day, we don't yet know for sure if our wearable devices will help detect and curb the spread of COVID-19.
In the meantime, keep in mind that your fitness tracker can help you keep up with your everyday health and wellness during this pandemic — which is important for building a strong immune system.
In addition, you can also make sure you're staying committed to preventive behaviors we do know to be helpful, such as: