It’s 2019, and the days of simply tracking our run times with a Casio watch bought in aisle six of Target are a thing of the past. Joking aside, seriously, the fitness wearable market has exploded in the last couple years. I’ll bet someone sitting next to you while you’re reading this has an Apple Watch on, or maybe you do. Smart watches and fitness trackers like Fitbits or Whoop bands have given us the ability to observe a plethora of information about how our body functions throughout the day. The big question that comes with all this available information then becomes how accurate is it?

I’m going to have to burst your bubble and tell you - not very. That being said I think they do have a lot of applicable uses (I even wear one myself). The problem arises when people get stuck on the number (or rings if you’re an apple watch user) on their wrist and forget to see the bigger picture.

To be frank, fitness trackers as a sole tool to engage in and succeed in weight loss or increase one’s level of fitness do not work. A study out of the University of Pittsburgh that ran for 2 years between 2010 and 2012 found that, in a study population who combined a weight loss program with a fitness tracker versus a group who just used the weight loss program without the tracker, the non-tracker group lost more weight (results published in the Journal of the American Medical Association). Let me break down why this happens (and why it happens more often than you’d think).

1.    How do fitness trackers work?

There are several ways your typical fitness tracker works. First, when it comes to the original function of wearable trackers - step counting - trackers use accelerometers, which are three-axis motion sensors to tell you how you’re moving through space and how many steps you’ve taken. Honestly, this is hard to screw up and most fitness trackers have decent accelerometers in them. From there the functions of trackers become more in depth, and the accuracy of the metrics they track may fall off.

The next major step in the tracker game was heart rate tracking. Most popular trackers, Apple Watch, Garmin’s Vivosmart series and Fitbit, track heart rate using optical sensors (that little green laser thing on the back) to light up the capillaries in the wrist and count the heartbeats. That is about as accurate as it sounds; shine a light at your skin and watch what happens underneath. The point is that they’re really just taking a guess at how fast your heart is beating. It was a good try though.

2.    How accurate are they?

The data collected by trackers are put through an algorithm to tell you all the other metrics you may desire to know. For a lot of people, calories burned is at the top of this list. The tracker needs to account not only for heart rate, but also body metrics (height, weight, age, etc.). Now, companies like Apple or Garmin don’t make these algorithms public, so then it becomes a bit of a guessing game as to how much they can be relied upon (

3.    So what?

So now you might be questioning why anyone would purchase a tracker, or if Apple can really be that good. Well, let me tell you why trackers are so popular and why you may still want to go buy one.

According to research out of the University of Pennsylvania, fitness trackers do a really good job of motivating people to be active in a variety of ways. Specifically, one of the best ways found was through fitness trackers’ integration with social networks, allowing for the formation of community and competition based on the metrics that can be tracked by your wearable. They also are a good way to track a “me vs. me” competition within ourselves to beat our steps, miles walked, or active calories burned a day.

Also, fitness trackers are evolving. A lot of the research on their accuracy is fairly old now, and while new studies haven’t been done to quantify the newer tracker’s accuracy, based on the research going into not only the hard, numeric data but also the psychological and mentality edge fitness trackers may be able to offer (via goal setting, competition, etc.) we can at least hope that they’re becoming more intricate, useful tools rather than just another screen we carry around.

Bottom line: if you like it, use it. There’s absolutely nothing wrong with having a good pulse on where you’re at day-to-day health wise. And, in a growing fitness technology market, a cheapish watch or band is a great, cost-effective way to do that. That said, just take your numbers with a grain of salt, and don’t make your Apple Watch your new Bible. It’s just one small tool in your arsenal. Don’t forget the basics and don’t let the numbers run your life. The most important thing in any exercise endeavor is to have fun and stay consistent. If a wearable fitness tracker helps you do those two things, then go for it.