Most of us have heard at some point that we should be walking around 10,000 steps per day. This figure is now commonplace across many of the health apps and fitness bands that are downloaded and sold in the millions. But how useful is it? Does the tech actually work?

Well one researcher, who gave a talk at the American Association for the Advancement of Science annual meeting in Boston, has called them into question. Greg Hager, a professor of computer science at John Hopkins University, claims that this 10,000-step goal, and many other targets that health apps and technology use, may be “doing more harm than good” as they are not grounded in science.

“Some of you might wear Fitbits or something equivalent, and I bet every now and then it gives you that cool little message 'you did 10,000 steps today,'” Hager said at the meeting. “But why is 10,000 steps important? What's big about 10,000?”

It turns out that the origin of the 10,000 steps a day minimum is not actually based on any hard science. It seems to have roots in one study conducted in Japan during the 1960s that found health benefits associated with men burning an extra 2,000 calories a week. This, the researchers say, equated to about 10,000 steps every day. In fact, early pedometers sold in Japan during this period were even known as “manpo-kei”, which translates as “10,000 steps meter”, and became popular among Japanese walking clubs.

“But is that the right number for any of you in this room? Who knows? It's just a number that's now built into the apps,” Hager continued. “Without any scientific evidence base, how do you know that any of these apps are good for you? They may even be harmful.”

While the arbitrary limit may be misleading, others dismiss the outright harm. A study released last year found that fitness trackers did not help the participants lose more weight when compared to more conventional weight loss strategies, though the authors of that study did point out that the push to get people moving more is clearly beneficial. “We need to be careful not to throw the baby out with the bathwater,” one of the authors, Professor John Jakicic, told The Guardian.

The biggest concern with these apps, however, may relate to those that purport to help manage mental health and medication. In these cases, there could be serious margins of error that could genuinely put people at risk. So while walking an extra 10,000 steps per week is probably not going to be a bad thing, the reliance on fitness apps to manage more serious conditions may not be so healthy.