Today’s Wonder of the Day was inspired by Jaiyla. Jaiyla Wonders, “How do Fitbits work?” Thanks for WONDERing with us, Jaiyla!
We were sauntering through the Wonderopolis jungle the other day when we overheard an interesting conversation between a monkey and an elephant:
Monkey: Hey Ellie! What's that thing on your trunk?
Elephant: Oh this? It's a fitness tracker. I'm trying to lose some weight.
Monkey: But you're the largest animal in the jungle!
Elephant: But I don't have to be!
We were impressed by Ellie's perspective on life. We're not sure whether or not fitness trackers are really catching on in the animal world, but we know they're very popular with human beings these days.
Today, wearable fitness trackers come in all shapes and sizes. Thanks to Bluetooth technology, they can communicate with your smartphone to give you instant feedback on a variety of parameters as you exercise, including the number of steps you take and what your heart rate is.
Pedometers that keep track of the steps you take have been around for years. Today's fitness trackers, however, take advantage of newer technology and sophisticated algorithms to track and estimate a wide variety of fitness measures, including how many calories you burn during exercise.
Most modern fitness trackers use a three-axis accelerometer as their primary sensor. This advanced piece of technology measures acceleration based upon start of motion, end of motion, and intensity.
Fitness trackers collect data that can then be processed with an internal computer chip and/or a smartphone application. The data is processed with proprietary algorithms that convert the data into useful statistics, such as number of steps and miles walked.
Depending upon what kind of fitness tracker you have, it may have additional sensors. For example, an altimeter can measure altitude to track the number of flights of stairs you climb. Optical sensors can measure your pulse by shining a light on your skin. Sensors can even measure wrist movements during sleep to let you know if you're getting quality sleep.
Unfortunately, fitness tracker sensors aren't perfect. Data gathered can vary widely across different devices. They're also affected by peculiar arm movements, gesturing, and unintentional movements.
Even if fitness trackers aren't perfect, they still help you exercise more and lose weight, right? Well…recent scientific studies have called the efficacy of fitness trackers into doubt.
For example, one recent study measured weight loss in a group, half of which self-reported their diet and exercise and half of which used fitness trackers. At the conclusion of the study, the group with fitness trackers had lost less weight.
The scientists conducting the study suggested that fitness trackers may overestimate actual physical activity, leading people to believe they've exercised more than they have and therefore can eat more. Others suggested that failing to meet daily fitness tracking goals could discourage some people, causing them to exercise less and eat more.
This and similar research has led some experts to suggest that fitness trackers might not work the same for all people when it comes to losing weight and exercising more. They may work great for some people who are already motivated to exercise. For others, they might not make much difference in terms of making meaningful lifestyle changes.