He shrugs. Most people also assume he simply was born being able to do that- which is doing wonders for his secret identity back home. If you don’t think Superman has a secret identity you stop looking for it.

“A lot of training, at first I could only leap over really tall buildings. Now I mostly got the hang of it.” His landing is still a little rough, but he’ll get there eventually. “The planet where I was born had a red sun, and a harsher atmosphere. That and a bigger pull of gravity made it so my body adapted to those conditions.”