Every night during sleep, our bodies produce a wealth of information. Each breath and heartbeat tells part of a story. Capturing and tracking that data over time can bring a deeper understanding of your holistic health and wellness.
To help you gain a deeper understanding of what your body is saying, Fitbit has developed a Health Metrics dashboard available soon to Premium members that will display five health metrics to help you see trends in your overall well being. After wearing a Fitbit tracker or smartwatch* during sleep, you’ll see nightly averages and graphs on the Health Metrics dashboard—important information that can help you uncover trends and changes to your wellbeing.
The Health Metrics dashboard measures and tracks:
Skin temperature variation is the variation in skin temperature taken from your wrist while you sleep versus your baseline. Warming up and cooling down through sweating or the dilation and constriction of blood vessels near the skin is how the body regulates itself and keeps your core temperature stable. It is normal for your skin temperature to vary during sleep and from night to night. Tracking your skin temperature variation can help you uncover changes to your wellbeing. Factors that can cause variation in skin temperature include your circadian rhythm, changes to your menstrual cycles, or the onset of fever.
Breathing rate is the number of breaths taken per minute. Typically, an individual’s average breathing rate won’t vary significantly from night to night and even a small increase in your average breathing rate could be meaningful. Factors that can affect your breathing rate include age, gender, weight, fever, or other conditions such as heart conditions.
Resting heart rate is the number of times your heart beats per minute when you are still and well-rested. Fitbit trackers and smartwatches with heart rate tracking capabilities can estimate your resting heart rate by measuring both when you are asleep and awake. Resting heart rates, which typically range between 60 to 100 beats per minute, may go higher or lower based on a variety of factors including your overall fitness, stress, and illness.
Oxygen Saturation (SpO2) estimates the amount of oxygen in the blood. Fitbit smartwatch wearers will be able to install the free SpO2 Signature clock face, which leverages data from the red and infrared sensors on your Fitbit device to measure estimated oxygen levels in the blood while you are sleeping. Oxygen levels in your blood stay relatively constant day to day, although they are typically lower during sleep when breathing slows down. And if you want to track your trends over time, upgrade to Fitbit Premium to view your SpO2 stats over the past week or month with the Health Metrics dashboard in the Fitbit app.
It’s important to note that Fitbit does not measure or display SpO2 values below 80 percent.
Heart rate variability (HRV) is the variation in the time between heartbeats. Measurements of the variations in time between each heartbeat can reveal your body’s balance between “fight or flight” modes and periods of “rest and digest.” Higher heart rate variability is considered a sign of a healthy balance between both heightened and relaxed states. A significant drop in HRV may indicate that the body is under some type of stress—whether from external factors like a difficult situation at work or showing potential signs of illness.
The goal of the Health Metrics dashboard is not to take a momentary snapshot of your wellness, like you would get during an annual checkup, but to allow you to track your changes day to day, over a week, or throughout a month. Those changes can be revealing of both physical or mental wellbeing.
While each of the five measurements tells part of the story of overall wellness, seeing them together can be the most revealing. Because the body’s autonomic system is interconnected, these five metrics can tell more in concert than individually. For instance, increases in breathing rate can be connected to drops in oxygen saturation levels in the blood. Similarly, a rise in resting heart rate tends to result in a decrease in heart rate variability. The body is a holistic organism, after all, with each organ, system, and function affecting the whole.
Why Now
Staying in touch with the subtle signals your body is sending is more critical than ever. COVID-19 has impacted the world’s wellbeing far beyond the tens of millions who have contracted the virus. The disruptions to daily routines, including exercise, the stress of social isolation, and the ongoing feelings of uncertainty are having a cumulative impact on our minds and bodies. After the implementation of social distancing guidelines, one-third of Americans say they have experienced high levels of psychological distress. Studies around the world have shown similar results.
Tracking signals through the Fitbit Health Metrics dashboard can help you take proactive steps to maintain overall wellbeing.
“COVID-19 has shown us all how critical it is to take care of both our physical and mental wellbeing,” said James Park, co-founder and CEO of Fitbit. “Our mission to make everyone in the world healthier has never been more important than it is today.”
For over a decade, Fitbit has pioneered fitness tracking, helping people take control of their health and wellness. With the sudden spread of COVID-19 across the world, the job of providing users with access to new health metrics has taken on new urgency.
“We believe now is a time when our mission is more important than ever,” said Taylor Helgren, Vice President of Product Management for Fitbit Health Solutions. “The team’s been working incredibly hard on the Health Metrics project. As the pandemic became more and more real, we began to work nights and weekends. We saw it as an opportunity to make a difference.”
Future Path
The importance of early detection of illness has accelerated Fitbit’s research with leading medical institutions including Stanford, Scripps Research, and King’s College London to see if wearable trackers might be an effective early warning system for signs of COVID-19. While the Fitbit Health Metrics dashboard is not intended to diagnose or treat medical conditions and should not be relied on for any medical purposes, Fitbit continues to research new uses and connections that may be present in Fitbit data.
In May, Fitbit asked users to participate in a study to help develop an algorithm that could predict the onset of COVID-19 before symptoms. In all, over 150,000 people from the Fitbit community have volunteered to help. Early results suggest that changes in breathing rate, resting heart rate, and heart rate variability can be detected simultaneously with the onset of COVID-19.
“It’s clear that our bodies start to signal impacts from the disease before more noticeable symptoms appear,” said Conor Heneghan, Director of Research Algorithms at Fitbit. “With these initial signals identified, we’ll continue our work developing an algorithm to detect diseases like COVID-19 and focus on expanded research in a real-world environment. This study presents an exciting opportunity to see how the power of the Fitbit community will help us better understand this new and complex disease.”
“Wearables may be able to play an important role in the early detection of infectious diseases by acting as an early warning system for our bodies,” said Eric Friedman, co-founder and CTO of Fitbit. “This research shows great promise to help us understand and detect COVID-19, but can also serve as a model for detecting other diseases and health conditions in the future.”