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How Fitness Trackers Work
Ever wonder how a fitness tracker counts your movement and heart rate? Peek inside to learn about the accelerometer and gyroscope that sense how you move, and the optical sensors that watch blood pump through your body.
How it works
- Press play to start the video.
- Videos 5 minutes or longer pause once or twice for a quick check. Get it right and you're on your way. If not, you'll see a friendly explanation and the video simply keeps going. Short videos skip the checks.
- At the end there's a 4-question test. Score 60% or more to complete the lesson, and 80% or more to master it. You can always watch again and try for a higher score.