Against Steps

Tracking the number of steps you take in a given day is not a useful measure of anything. It doesn't serve as a proxy for overall activity level. It doesn't serve as a proxy for distance over time. It doesn't provide an estimate of calories burned. Two people with very different overall levels of health can take the same number of steps in a given day and cover very different distances. Walking 5,000 steps is not equivalent in any way to running 5,000 steps, except in mere step count. Two runners covering the same distance can and will have very different step counts, depending on their height and their running form and speed. Even two runners running the same speed and distance can have different step counts.

Step counting is, therefore, meaningless as a measure of activity or health. Luckily for all of us, there are plenty of alternative measurements we can use to estimate our activity level and to work toward a goal of bettering our health.

I suspect that the main reason step counting became so pervasive in the world of activity trackers and smart watches is because it is technologically easy to measure. The "problem" of pedometry, if indeed it ever was a real problem, was solved back in the 1970s or 1980s, when someone figured out how to put a little shaker inside a plastic doohickey and attach it to an LCD digital display. For all I know, there were already analog pedometers out there before then, but I never saw one. It's not clear to me that the people ever demanded such a contraption as a pedometer. My first encounter with them was when my friends' parents and grandparents received doctors' orders to start increasing their activity level for health reasons. Sometimes the reason was to lose weight, sometimes the reason was to rehabilitate an injury, sometimes the reason was to recover from surgery. These folks were given pedometers and told to take an arbitrary number of steps per day, with that number presumably increasing until some therapeutic goal had been achieved.

In this light, I can see the rationale behind step-counting. For a recovering heart surgery patient, I can see how taking first 2,000, and then 3,000, and then 5,000 steps per day could be an important path toward rehabilitation. I can see how this advice would be far more medically meaningful than telling the patient to "try to walk around the block tomorrow, but if you can only make it two mailboxes down the street before you have to come back, no big deal." Providing patients with a number that can be increased over time can provide them a means by which to track empirical improvements in their recovery while still ensuring that the recovery is more or less individualized to each patient. This is especially true for people who have never trained for any sort of competition, people who need easy exposure to the concept of training without having to feel overwhelmed by a "training regimen."

That, however, comprises the limits of my understanding of step-counting. Beyond this kind of medical scenario, there is no reason for anyone to count their own steps, to challenge each other to step-taking competitions, and to measure their daily health by the total number of steps they've taken.

To give you some level of how absurd this sort of thing is: two weeks ago, I placed 3rd in one of Garmin's step-taking competitions despite running more than 60 miles that week and putting in three days of more than 12 miles of running. While it is always possible that the two people who placed ahead of me in the step competition were training even harder than I am, it's highly unlikely, since I train harder than about 98% of the fitness-tracker-equipped population. Statistically speaking, I should win these competitions about 98% of the time, and place second in the competitions I don't win outright. But that is not the case. In reality, I often place below the top 5 out of 10 participants.

The reason I lose, of course, is because I take nice, long strides and go really fast; not just when I'm running, but also when I walk. Someone with a shorter stride length who covers the same distance will exert himself less while taking more steps and beat me in a step-counting challenge. But who is in better physical shape?

If counting steps is not indicative of anything useful for gauging fitness, what else can we do? Well, I happened to write about Training Load just the other day, and I think this is a pretty good measure of how much exercise a person gets. It's hard to argue with a linear combination of time spent exercising and relative heart rate increases. No wonder academic physiologists have been using measurements like these for half a century.

The downside to comparing a community of recreational activity tracker users by something precise and objective like Training Load is that those who don't get much exercise may start to feel discouraged. Why keep trying to beat last week's effort if you're in the fifteenth percentile of people who exercise? On the other hand, if you're in the fifteenth percentile, but you can win a bunch of step-counting competitions, that may provide you with better incentive to keep exercising. At the very least, it provides you with better incentive to keep paying for and using fitness trackers and apps. Thus, it comes as no real surprise that profit-maximizing fitness tracking firms would provide their customers with a measurement that has high motivational value despite its low physiological value.

Still, one of the unintended consequences of this approach to fitness tracking is that it draws a larger crowd of unserious athletes than it draws serious athletes. It's good that so many unfit people are motivated to go couch-to-5K using step-counting competitions to get them there, but ultimately races stop catering to good, competitive runners. In some cases, race organizers stage two separate events, one for competitive athletes and the other for fun-runners. The major commercial draw, of course, is the fun-runner race: the exact opposite of what the major draw ought to be.

We ought to live in a world in which seeing great marathoners edge ever closer to breaking the 2-hour marathon barrier is an exciting spectacle. We ought to live in a world in which fast runners awe us and inspire us. Instead, we live in a world in which the fifteenth percentile can regularly best the ninety-eighth percentile in a "step challenge," and nobody who enters the Boston Marathon actually cares who wins!