Everyone knows wetsuits help keep you warm in cold water. Lesser known among the general public (but well-known among triathletes) is that wetsuits also make you swim faster! The buoyant neoprene in a wetsuit floats a swimmer higher in the water, decreasing drag and thus increasing swim speed.
But how much faster is a wetsuit? I’ve heard various rules of thumb: 10% speed increase; 4-6 seconds per 100m; 1 minute per kilometer. I’ve also heard various caveats: it depends on the swimmer’s skill (better swimmers benefit less); it depends on the swimmer’s body-type (naturally floaty people benefit less); it depends on the quality of the wetsuit (you get what you pay for); it depends on the fit of the wetsuit; and so forth.
So the answer is: It depends. Because I’m usually disinclined to let things go at “it depends,” I decided to conduct a field experiment. Reef & Run, which I’ve written about previously, provided the perfect laboratory. Almost every Thursday evening between June 21 and yesterday, August 23, I swam one mile in the ocean at East Beach in Santa Barbara.…