A 10-month-old hamster named Mollie routinely covers nearly 70 kilometers a week on her exercise wheel. Her owner, physicist Thijs de Buck, engineered a system that automatically uploads the nightly data to the fitness app Strava. Mollie's personal best so far is 11.15 kilometers in a single night.

A 10-month-old hamster named Mollie routinely covers nearly 70 kilometers a week on her exercise wheel. Her owner, physicist Thijs de Buck, engineered a system that automatically uploads the nightly data to the fitness app Strava. Mollie's personal best so far is 11.15 kilometers in a single night.