yeah...a kid? A woman? His gait is very odd. that is why someone knows who he is.
It looks like a man to me, fat but perhaps short. He looked about average from another camera - that was a fish-eye lens that made him look so small.
In any case, I think his gait is so weird because he’s trying to keep his baggy shorts up. Notice what looks like underwear sticking out over the top as he runs. They run with their knees angled outwards so the pants won’t slip over them.
Definitely odd, though, whatever the cause.