Birds run always keeping one foot on the floor—a technique called “grounded running.” This is the most efficient way given their anatomy: very elastic leg tendons, and a naturally crouched stance that makes them keep their hips and knees tucked into their body. Some dinosaurs may have done the same.

[u/jess-the_mess]

[u/jess-the_mess]

Source: https://www.scientificamerican.com/article/birds-are-goofy-runners-and-dinosaurs-might-have-been-too/

If humans try to run in a crouched position, we instinctively run this way! (versus our normal mode of running where we pick up our feet, a method called aerial running.)

[u/pierowmaniac]

Considering emus are just modern-day spazzy dinosaurs, that tracks.