When It Comes To FITNESSING, Which is Better, A Psychological Boost or More Accurate Data?

Does it really matter if your fitness tracker over-counts your steps during a given day?

Nov 20, 2013 at 1:30pm | Leave a comment

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A few weeks ago Marianne wrote about one of her fitnessing strategies: measuring progress without measuring weight. One way to do that is with a fitness tracker. The one Marianne uses, the FitBit Flex, is one of the more popular tracking devices in an increasingly crowded field of choices. Makers of these devices try to differentiate their wares by coming up with new form factors (wrist-wearable vs clip-on), trading on brand recognition (Nike, Adidas), or claiming greater accuracy and better data.
 
The folks behind the Basis B1 Band are the most vocal about how accurate their product is compared to others. The claim is that people who think they've been walking 10,000 steps a day because the FitBit says so apparently aren't because most trackers over-count. 
 
I've used several fitness trackers over the past couple of months and I admit that this has bothered me. I live in New York City and take the subway all the time. The bumpy, jangly, not-monorail-smooth subway. After a ride, most trackers recorded me as having taken steps when I was sitting down. Wrist-worn trackers sometimes inaccurately count hand movement as steps as well.
 
The only reason I know these things is because I'm paying careful attention for the purpose of evaluation. Most people look at their trackers a few times a day to check up on progress or toward the end of the day to see if they reached their goal yet. Does it matter if they actually walked 9,100 instead of 10,000? Basis seems to think so.
 
I decided to test this myself. I wore the Basis B1 Band for a week and compared it to my experience with the FitBit One and the Whithings Pulse fitness trackers.
 
Step Counting and Accuracy
 
For three days I wore all three trackers at the same time so I could compare the number of steps recorded and see what kind of movement counted as a step for each. At the end of the day, the B1 did indeed show fewer steps taken than either the FitBit One or the Pulse. I couldn't fool the Band into upping my steps by flicking it, shaking my arm a bunch, or even walking in place like I could with the other two. After riding bumpy public transportation, the B1 only showed a few extra steps where the Pulse and One showed over a hundred extra on average.
 
Why does this happen? Fitness trackers like these use an accelerometer to determine if you're moving and an algorithm to interpret that movement correctly. The algorithm Basis uses is supposed to be better at ignoring any movement and vibration that is not you walking, thus it won't falsely inflate how many steps you've taken. 
 
FitBit is aware that this can be an issue. The way the company deals with it is by allowing users to time and log activities such as driving and riding the bus so they can eliminate the "steps" counted during those times. It requires knowing you need to do that ahead of time and remembering to start the timer, which not everyone does (I don't). With the B1 Band, owners don't have to think about this at all.
 
Other Kinds Of Tracking
 
Another benefit the B1 Band offers that few others do is constant heart rate monitoring. Since it's meant to be worn all the time as a watch, the Band can check your heart rate at any moment using the sensors on the back where it touches your skin. It records this data and uploads it to your online Basis account via your smartphone or computer.
 
In this way the B1 can also tell when you're engaged in rigorous activity--fitness walking as opposed to a leisurely walk around the corner to grab lunch--and when you're sleeping. 
 
By contrast, the Withings Pulse relies on third-party apps like RunKeeper to get this information and has to be told when you're going to sleep so it can monitor your nocturnal patterns. This approach does have benefits. 
 
When it comes to measuring your sleep patterns and activity levels, the B1 is actually not as accurate as it is when counting steps. This appears to be because the Band doesn't ask what you're up to and there's no way to tell it. So, if you start fitness walking but slowly raise your heart rate, the B1 may not notice for a while. And it can't tell you how long it took to fall asleep like the Pulse can since it will only notice you are out once your heart rate gets down to a certain level.
 
Again, I'm only aware of these distinctions because I've used so many different trackers. It does raise the question: how much does this data matter?
 
Accuracy vs Psychology
 
The whole point of this new generation of fitness trackers is to make people more aware of how much they do or don't move during the day and to spur them on to better habits. But the 10,000 steps number isn't special or magical, it's partially arbitrary. If my tracker claims I walked 10,000 steps and I only walked 9,000, or 9,500, so what? I still did more walking or exercising than I would have normally and at least I have some measurement of how well I did that day. If my goal is to get more sleep, the exact number of hours and minutes is less important to me than the fact that I am getting more because I set a goal and a piece of technology both reminds me of that and helps me track my progress.
 
Still, I know there are people who aren't as relaxed as I am about these matters. It bothers them that their FitBits and other trackers add extra steps. It feels a bit like cheating. If you're that type of person, the Basis B1 Band is likely to make you happier than the competition. 
I get how you feel. There's a part of me that is willing to do a bit extra to reach a goal if I'm super close. I might notice around 9pm that I'm at 9,600 steps for the day. That's 400 from the goal! I can take 400 steps, come on. I'll even do some of them walking up and down my stairs. 
 
The B1's recorded steps were sometimes lower by just a few hundred, sometimes by over a thousand, but never by a giant amount. That being the case, getting in those last steps to the goal mean I did even more than the more I did before. Just a bit more, sure. But sometimes little changes add up to big ones.