A study of French male triathletes "concluded that the wet suit amplified the coordination mode of the triathletes (i.e. catch-up coordination) without modifying stroke rate, recovery phase or leg movements."

Another study said "If you're a triathlete, you've got to like wetsuits. They keep frigid water from paralysing your arm and leg muscles and sinking your ship before you make it to shore, and they can improve swimming speed by 3 to 7 per cent, enough to give you a 50- to 100-metre edge over a suitless competitor in a 1500-metre swim."

"Thus, it makes sense to slip into a suit, even when the water is not especially cold (bearing in mind that suits are not allowed in sanctioned competitions over the Olympic distance when the water temperature is over 21 degrees Centigrade - or over 24 degrees for long-distance triathlons). "

My own experience in using wetsuits is while scuba diving.

A wetsuit makes one more buoyant, It should fit snugly to keep a thin layer of water between you and the suit. This layer keeps you warmer by a few degrees.

It can be difficult to put on, and sometimes it is easier if you step into it when it is wet, in the water, preferably. Especially if it is really tight.

Because of its buoyancy, you need to add a pound or so of extra weights when scuba diving.

Another benefit is protection from the sun's rays.

Wetsuits are good when you swim in saltwater. Since they fit to your body, it gives you better protection from cold water and avoid injuries and scratches when you snorkel and scuba dive. For competition swimming, companies who manufacture wetsuits claim they give you split second advantage per stroke and it minimizes friction to water compared with human skin.