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Your Fitness Tracker is Racist
Lots of people wear smartwatches and fitness trackers — nearly 40 million in the U.S alone. These fitness trackers not only measure steps, but also use sophisticated laser technology to monitor heart rate and other physiological measures of well-being. But the technology that manufacturers rely on was designed effectively with light-skinned people in mind, and according to researchers and reporters, is likely to provide erroneous readings for people with darker skin.
No wonder all that walking isn’t making me lose weight.
Not-So-Colorblind Tech
Let’s take Fitbit for example, which uses the industry-standard laser technology in its trackers. If you own one, you’ve probably seen the green lights peeking out from beneath the device when you take it off. These lights rest against the top of your wrist and are used to measure heart rate. In between heartbeats the volume of blood in your blood vessels declines. If a light is shined onto your skin, it reflects back in differing amounts depending on how full of blood your vessels are at the moment. The cadence of darkening and lightening blood vessels changes as a result of your heart rate, and this cadence is what the green lights in your Fitbit measure. They then convert this cadence into a relatively accurate measurement of your actual heart rate.
