Comparative anatomy - SLRPNK

I’d love to see an informed response as to why we think they ran instead of hopped. Is there a difference in the skeleton or muscles that would tell us?
Tyrannosaurus Trackways Reveal a Dinosaur's Walk

Scientists have found tyrannosaur footprints before, but never a trackway that reveal the dino's gait over multiple steps. Until now.

Popular Mechanics
Oh God imagine we’d actually found huge parallel footprints.
Then we’d know Jesus was carrying the t-rex the whole time