After watching USA swimming presents with Michael Phelps and Bob Bowman and a couple of other tutorials with the former on the butterfly stroke, I came to conclusion, as Bob Bowman puts it, that 'minimalisation of resistance is more important than force' and 'it's extremely important to maintain horizontal body position.' Therefore I musn't keep my head too high, because that disturbs my swimming. Bu then I saw Chad Le Clos and I can't help noticing that he's keeping his head much higher than Phelps when breathing and his body motion seems much more vertical. In spite of that, Le Clos seems to swim so effortlessly and light, like he was hardly puting any energy into his stroke. Can someone explain it to me, please? Thanks in advance.
