What to Know About Wearable Health Tech

The global market for wearable technology has grown extremely quickly and isn’t showing any signs of slowing down. In 2024, it was a $78.4 billion market and the field is projected to reach $191.58 billion by 2032, according to Fortune Business Insights.

Clearly, wearables aren’t just for optimizers or performance athletes anymore. Knowing more about how your body moves through the world can help all types of people if you know what you do with the data. So we asked our colleagues on the Atria Health Institute’s Performance & Movement team for advice on how to choose the right fitness tracker, the key metrics to watch, and their recommendations for making the most of your devices.

Benefits of data tracking

There’s solid evidence that paying more attention to your health can lead to improvements. A 2022 review in The Lancet examined 39 studies on wearable activity trackers and found that people using them took an average of 1,800 more steps per day, walked 40 more minutes, and lost about two pounds.

“Wearables can be really motivating,” says Rob Mahlman, PT, DPT, a physical therapist at the Atria Health Institute. “If you’re not into exercise, it can help you start or give you insight that exercise would be valuable, and on the other end, if you’re an athlete, the data can be a way to make sure what you’re doing is effective and giving you the results you want.”

The trends that wearables can reveal are key, according to experts. Rather than focusing on how a metric looks after any one workout, pay attention to how your data changes over time and what it does in response to regular activities or habits, like going to bed late or taking morning jogs.

The data from your wearable can also be a great starting point for conversations with your physician, physical therapist, or trainer, says Jessica Boyle, PT, DPT. “If you’re consistently using these wearables and start seeing major outliers in the data that don’t match changes in your activity, that’s when you go to your doctor and look at the data together,” she says.

This is especially true when looking at more medical metrics. The Apple Watch, Fitbit, Samsung Galaxy Watch, and Withings ScanWatch are all approved by the United States Food and Drug Administration (FDA) to detect irregular heartbeats, for instance. Apple also recently received FDA approval for its high blood pressure detection feature, and Whoop offers blood pressure monitoring (though its feature is not FDA cleared). Wearables can also detect falls, seizures, and other heart problems.

Beware of data overload

While data can be useful, experts recommend using it in a measured—not obsessive—manner. “This is one piece of your puzzle,” says Boyle. Each wearable takes some time (often several weeks, depending on the device) to learn your body’s patterns and build your baselines. Some data’s accuracy can also vary based on factors such as your circulation (because the devices measure your body’s temperature), skin tone (they use light sensors), and type of workout.

Boyle encourages people to focus on how their body feels before looking at their wearable’s data each day. If someone really wants to look at their sleep score or other metrics first thing upon waking up, she suggests they then try to go the rest of their day without thinking about the data and check back in the evening to see if their day matched the outlook from the morning.

Learning about the wide range of data that a wearable offers can be another way to avoid obsessing over any one number, according to Mahlman. He often sees people start by paying attention to one or two data points, and when they understand the technology’s broader capabilities, that allows them to see all the ways their body changes in response to both workouts and habits. Knowing how much of each sleep phase you got is one thing, for example, but if you can watch how your sleep changes after a particularly challenging workout, that can help you plan recovery days or days to push yourself further.

Metrics to watch

Here are some of the key metrics to track:

Steps: Tracking steps was one of the first things that early wearables could do, and most trackers still show your daily step count. Despite what we’ve all heard, you don’t have to reach 10,000 steps each day to improve your health. A study in The Lancet Public Health this year found that walking 7,000 steps a day is associated with 47% lower risk of dying and 25% lower risk of heart disease, and other research has found that every little bit helps.

Mahlman cautions though, it’s best to focus on activities that will result in taking more steps throughout the day rather than on “hacking” your steps by walking in place, for example, to get your wearable app to show you’ve met a specific daily number. “If you exercise more and do the things you should from a heart rate perspective, you’ll notice you’ll probably end up hitting your steps naturally,” he says. That can involve working out or making simple changes such as taking the stairs instead of the elevator and parking slightly farther away.

Heart rate: This is one of the foundational metrics that fitness trackers use to help estimate stress, sleep quality, and other conditions. Most devices use optical sensors, which shine a light on your skin to measure blood flow in your arteries. Some also use an electrocardiogram (ECG) that detects the electric current your heart generates.

• If you want to level up, chest strap heart rate monitors like the Polar H10 are even more accurate, says Mahlman, and many smart watches will pair with the straps via bluetooth.

Heart rate variability (HRV): This measures the fluctuation in time between heartbeats, and gives you a sense of how your cardiovascular system is responding to changes in your body. A higher HRV (more variability) generally means your body is responding quickly to activities or stress, while a lower HRV can suggest fatigue or sickness because your body is less able to respond to changes. There’s no one target here, as heart rate variability varies widely based on your specific health circumstances. But it can be useful to track HRV compared to your baseline and see what it looks like during times when you’re energized or feeling sick.

Heart rate zones: These tell you how vigorously you’re exercising. Federal guidelines recommend people get 150 minutes of moderate-intensity exercise (typically zone 2 or 3) or 75 minutes of vigorous exercise (zones 4 and 5) each week.

VO2 max: VO2 max measures the volume of oxygen your body can use during exercise, and it’s a powerful indicator of cardiovascular fitness and overall health. Fitness trackers estimate this using algorithms that combine heart rate, age, sex, weight, and the intensity of exercise, but our experts suggest an extra dose of caution here. True VO2 max testing (as we wrote about previously) involves working out on a treadmill or bike while wearing a mask that measures how much oxygen you’re inhaling and how much carbon dioxide you’re exhaling. Some places (including Atria) also estimate VO2 max using a treadmill stress test called the Bruce protocol, but VO2 max testing isn’t safe or appropriate for everyone, Mahlman says, and an estimate from a fitness tracker may help you see what direction you’re moving in, especially checked once or twice a year.

What to consider when choosing a wearable device

The best one for each person will depend on your individual needs and preferences. Here’s what our experts say to think about when shopping:

• What are your goals? Each wearable is geared toward different kinds of tracking, so Boyle suggests starting any search by thinking about how you hope to use your device. If you run regularly (or want to start), the Apple Watch or Garmin watches are popular choices for their accurate step counts and activity monitoring, for example, while hikers and trail runners often prefer Garmins for their precise GPS capabilities. The Oura smart ring offers comprehensive health and lifestyle tracking with robust sleep monitoring, but many people who lift weights prefer to take the ring off when doing so, which can limit its utility for that kind of workout. The wrist-worn Whoop, on the other hand, is beloved by fitness enthusiasts and has advanced coaching features, but it and Oura both require monthly app subscriptions to get the most out of their vast amounts of data. Fitbit, one of the original fitness trackers, still has highly rated, more simple devices that are less expensive than more specialized wearables.
• How much do you want the device to be in your life? Some people like that the Oura ring and Whoop strap don’t have screens to distract them, while others enjoy being able to receive notifications on their Apple Watch while out and about.
• What feels comfortable? Think about whether you want to sleep with a smart ring on your finger, whether the Whoop’s band feels good against your wrist, or if a given device matches your aesthetic so you’ll want to keep wearing it, says Boyle.
• What does the app look like? A huge part of using wearable technology is being able to navigate the accompanying app, so experts advise taking time to look into this before you commit.
• What other features do you need? If battery life is crucial for you, the Apple Watch may not be the best pick, as even its latest version lasts for just a day or two compared to over a week for many other fitness trackers. And while most devices come with some health coaching, test out the workout guides and tips a device offers to see whether it fits with your lifestyle.

The bottom line

Wearable technology can offer a host of insights into your workout routines, fitness, sleep, and overall health. As Mahlman says, the devices can start to answer the question “is your body working the way you want it to?” The best way to use the data is as one tool in your health arsenal that can help you tune into your body’s responses to various activities and guide choices you make for your personal health goals.