Does Shaving Your Legs Make You Swim Faster?

Hair causes a drag effect in the water.

For the average swimmer shaving the legs would have a negligible effect. In competition, however, in which every advantage is necessary, leg shaving can improve times. Body hair causes resistance against the water. Shaving reduces the resistance.

Resistance

Looking at nature, the best swimmers are smooth and hair free. Body hair increases a hydrodynamic force called laminar flow. Laminar flow creates ripples as the water passes over an uneven surface, slowing the swimmer. Shaved legs are smoother and create less laminar flow.

Improvements

Shaving your legs makes you swim faster, but the differences are only noticeable if you are swimming consistently well. Many swimmers shave their entire body in order to get every tiny advantage.

Alternatives

Shaved legs provide an advantage because there is less friction from the body on the water. Body suits and swimming caps also reduce the friction created by hair, but a body suit has the disadvantage of making the swimmer slightly heavier. Some high-tech body suits have been banned because of their air-trapping effect.

References

• Why Swimmers Shave Their Bodies
• NBC Sports: Record Setting Swimming Bodysuit Banned
• Discover: The Physics of Swimming

Resources

• NBC Sports: Phelps Will Shave