A screenshot from a viral Reddit video of a senior dog with arthritis "doing the zoomies" in a backyard. A screenshot from a viral Reddit video of a senior dog with arthritis "doing the zoomies ...

A 21-year-old dog has captured hearts online ... with youthful energy went viral on Reddit. The post, titled "My 21-year-old good boy, doing the zoomies," was posted by u/valulaa and has received ...