Do fitness trackers actually work?

My guilty pleasure is Quora, which I dip into if a question intrigues me. Sometimes I “archive” the more interesting topics here.

Do Wearable fitness trackers actually work?

Yes and no. Complex fitness trackers, like Garmin watches, are excellent for people who already want to exercise a lot and use metrics to meet performance and recovery goals. For those people, the value of wearables is unquestionable – it’s just a question of which model gives them the right mix of features, and they’ll come to that question with lots of knowledge and specific preferences.

Simple fitness wearables, especially those that are designed to blend in better with non-exercise clothing, work on the principle that if you give people information, they will make better choices. In general, that doesn’t hold across the board for people (look at the range of ideas out there about vaccination, for example), but at least in the case of wearables, you are usually talking about people who are already interested enough to buy one.

When people ask whether fitness wearables work, they usually mean “do people who wear fitness trackers exercise more?” Any stimulus for behavior change has to have 3 elements: the person has to know what to do, it has to be achievable, and the stimulus has to be salient. That’s different from “you have to really want to” – it means you have to notice it and respond to it in a predictable way.

The design of a fitness tracker can make or break the response even of a person who wants to use a fitness tracker. I tested a Nike Fuel Band almost 10 years ago. In many ways it was a nice device, although I wasn’t really the ideal user for it. It had one “feature,” though, that made me hate it. You set an activity goal and throughout the day, as you racked up more activity, a line of colored dots would change from red to green. So far, so good, right? But any changes to the activity goal only took effect the following day. While I was testing it, I had an injury early one day, and then was followed around by this red line all day even though it would have been absurd for me to pursue the goal. I was actually amazed by how angry it made me, and I’m a confident, knowledgeable exerciser who was just testing the thing for a week. (I have a dim memory of really enjoying some of the other ways it presented information, but at this remove, all I can remember clearly is that infuriating red line!)

I believe the rationale for limitations like that is “accountability” – to reduce the temptation, if a goal is not being met, to simply make the goal easier. OK but we’re talking about a goal that is supposed to serve the individual, not a test that’s being graded by some outside authority figure. Accountability is going to look different for different people, and the concept of a rigid daily goal with a constantly visible indicator is problematic. Among other things, it “punishes” you for having a rest day. You should have goals but you should also have a clear and healthful balance between “getting the check mark” and putting your foot down (or, perhaps, feet up) when you need to.

In principle, pedometer-based trackers are great for people who want to move more because they offer a clear indicator of how much movement is being done. This can be disheartening but the key as a beginner is to choose an attainable initial goal, even if it seems easy right away. I always urge people to think carefully about what they want out of a tracker to be sure they are not going to resent what it tracks or how it presents information. This can be a long conversation that ultimately touches on things that are unknowable or not much fun to talk about, especially for someone who is struggling to be more active and whose strongest associations with exercise are some crappy middle-school gym class experience. Fortunately, there are quite a few inexpensive options out there to let a person dip their toe in while they learn what will end up being most important – and most helpful.

So do fitness wearables work? Yes and no. Can they work? Definitely.

My answer on Quora