Almost all aquatic animals are slippery, but why? Answer is very simple slippery body is helpful for swimming. Aircrafts have rounded nose and structure due to aerodynamic consideration. Even submarines are made considering this factor. So, why not for human?
This is the reason why swimmers use expensive swimsuits in professional competition. These swimsuits help swimmers by reducing drag. But there is a natural alternative, which is body shaving before the competition. It includes arms, legs and torso. In competitive sports a tiny fraction of a second may be important and swimmers with shaved get little advantage due to reduced drag. It is thought that Australian swimmers first introduced body shaving in 1956 Olympics and cyclists have been shaving their legs for nearly hundred years. It is experimentally proven that cyclists can save around one minuets in 25 mile race. Study also supports the idea that shaved body reduces drag significantly during swimming.
Many experts say, even if body shaving doesn’t help it gives a psychological advantage. Shaving razor also increases skin sensitivity by stripping dead cells from skin which gives confidence to swimmers. Not only swimmers and cyclists but also some sprinters shave their body to reduce air drag.