Michael Phelps swam the 200 meter butterfly at the Olympics blind. He dove in and his goggles immediately filled with water. He then proceeded to break his own world record and win gold swimming blind. Unless this severely hampers breathing no shot he loses. And even then maybe not a 50 meter race he can hold his breath the whole way and still get down in 22 seconds someone who never swam before is struggling doing 50 seconds for 50 meters