Could you benefit from wearing a swimskin in your next warm-water race?
The swimskin is a relatively new piece of equipment in triathlon. It is a smaller, thinner and non-buoyant replacement for a wetsuit that is worn over a race kit when the water is too warm for a wetsuit (by USAT standards for age-groupers, 78 degrees). A swimskin is designed to be very snug and worn only during the swim leg. It enhances speed through the water despite lacking buoyancy by compressing the body and creating minimal friction with the passing water. The swimskin provides a solution to maintain speed and hydrodynamics in the water while wearing a bulkier (read: not completely skin-tight) tri kit. Just note that sleeves that cover your shoulders cannot legally be worn in a non-wetsuit swim, so if your race kit has them, you’ll need to roll down the top half of your kit under your swimskin or risk disqualification.
Only a few races, including the Ironman World Championship, are always a non-wetsuit swim, but if you race a lot, consider buying one for the just-in-case scenarios. Before you decide to use one in a race, weigh the costs and benefits: Will the water temperature be cool enough—and is it more beneficial—to wear a wetsuit? Consider the length of the swim leg and estimate if the time gained by wearing a swimskin will outweigh the time spent removing it in transition—removing one takes at least 15 seconds.
In the end, fit and comfort are most important when picking a suit. If the swimskin fits correctly and does not restrict or impede your ability to swim, it will probably save a little time and energy.