Michael Phelps starting plunge in style?

Question

Can anyone tell me what's the style of Michael Phelps plunge in at the starting? While most of us (the swimmers in my school) locate our both hands in straight line on land at the starting grid ready to jump, I notice his hands are at the side like a sprinter while running. Why?

Answer 1

He pulls his hands back and lifts his head to get a good drive off the block, or as you said 'starting grid'.