In the early days of Big Shot Comics Skyman, drawn by Ogden Whitney, was presented as a large musclebound hero. Eventually Skyman was drawn as a more lean character. Frankly, I think the big arms and chest make him look a little top-heavy, and perhaps the folks who produced Big Shot Comics thought so, also.
Skyman was a rich playboy (yawwwwnnnnn), who used his tricked-out plane, the Wing, to help him catch criminals. The rich guy who has nothing better to do than put on a mask and costume and fight crime was done to the point of absurdity in those days, but it made it easier to explain how he had the money to get by without having to go to a day job.
From Big Shot Comics #3 (1940):
More Skyman, first with his big muscles, then as he was after trimming down.