Zone3 Triathlon Wetsuit Guide

In most UK triathlons with open water swims under 22°C, a wetsuit is permitted and strongly recommended. Triathlon-specific wetsuits add buoyancy that lifts your body position, reduces drag, and saves energy for the bike and run. World Triathlon and British Triathlon rules require wetsuits below certain water temperatures and prohibit them above others, so check your race's specific rules for the day.

A correctly fitted triathlon wetsuit feels noticeably tighter than anything else you've worn in the water. On land it should feel firm across the chest and shoulders, with no loose material or air pockets at the lower back or thighs. In the water, horizontal, it releases and moves with you. If you can't take a full breath on land, size up. If there's loose material anywhere, size down.

Snug everywhere, restrictive nowhere. The compression is what creates the buoyancy and the hydrodynamic profile, so a triathlon wetsuit should always feel tighter than a surf or general-purpose wetsuit. If breathing feels laboured on land, the suit is too small. If you can pinch loose neoprene anywhere across the torso, it's too big.

Triathlon wetsuits use multiple neoprene thicknesses across the suit, not one uniform thickness. Standard construction is 5mm in the chest, core, and upper legs for buoyancy, with 1.5mm to 2mm at the shoulders and arms for flexibility. This is the optimal balance for race-pace front crawl in open water between 14°C and 22°C.

A triathlon tri suit, tri shorts, or a swimsuit. The point of wearing a tri suit is that you wear it through the swim, bike, and run without changing, so it goes on under your wetsuit. Avoid cotton or absorbent fabrics, which add weight and cause chafing.

Start at the ankles and work the neoprene up your legs in sections, smoothing out any air pockets as you go. Pull from the inside, not the outside. Use the pads of your fingers, never your fingernails, to avoid tears. The Silk-X linings used in the Aspire and Vanquish-X make this significantly easier than most suits, but every neoprene wetsuit requires patience on the first few wears. It gets easier as the suit breaks in.

A well-maintained triathlon wetsuit lasts for many seasons of regular open water swimming. Performance declines slowly over time as the neoprene loses some buoyancy and flexibility. Rinse with cold fresh water after every swim, dry inside-out away from direct sun, and store flat or on a wide hanger. Avoid hot water, chlorine where possible, and never put a wetsuit in a tumble dryer.

Yes. Zone3 wetsuits were independently tested at Loughborough Sport in 2025 by physiologist Dan Thornton across three athletes and four 750m swims each. The full testing methodology and results are published in the Zone3 wetsuit testing report.

The Glide or the Agile. Both are built for first-time open water swimmers, prioritise confidence in the water, and are easy to get on and off in transition. The Agile sits one step above the Glide, with Yamamoto #39 neoprene and a slightly more refined cut. Most first-time triathletes choose the Agile.

The Aspire for serious age-groupers, the Vanquish-X for elite-level athletes. Both are built for race distance and feature premium Yamamoto neoprene, SCS coating, and Pro Speed Cuffs for fast transitions. The Vanquish-X recorded the largest gains of any suit tested at Loughborough Sport, making it the suit of choice for athletes targeting marginal gains across a full Ironman swim.