Fitness Tracker
- Episode aired Dec 8, 2022
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Hannah Fry finds out how 1970s car crashes helped us to count our steps, why high-altitude WWII dog-fights led to a crucial health monitor and how fitness trackers are even being used to cat... Read allHannah Fry finds out how 1970s car crashes helped us to count our steps, why high-altitude WWII dog-fights led to a crucial health monitor and how fitness trackers are even being used to catch killers.Hannah Fry finds out how 1970s car crashes helped us to count our steps, why high-altitude WWII dog-fights led to a crucial health monitor and how fitness trackers are even being used to catch killers.