It's not the legs OR the strength OR the shape. It's the Mako treatments, he swears. She could more than keep up if not for those of course.

"Sorry," he said, coming to slow down a bit. "Guess I got really used to solo missions for a long time. And I can't blame it if it's got to get food for itself. But the chocobos can't defend themselves, they aren't the wild sort with magic."