Take the plunge with these tested suits.
11 Q&A: Gordon Benson
routine? Then youre probably going to need one of our expert-tested wetsuits to train in
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Q&A: Gordon Benson triathlon or adding open-water swimming to your cross-training routine? Then you're probably going to need one of our expert-tested wetsuits to train in.
The best wetsuits offer a layer of insulation against Britain's infamously chilly waters, allowing you to swim in comfort for longer, while also providing some buoyancy and protection against any floating debris.
What should I look for in a wetsuit?
The best wetsuit for you will depend on what you want to use it for, as competitive triathletes will have more demands than casual paddlers. That said, there are some common key factors to consider.
Fit
Quite simply, your wetsuit will be useless if it doesn’t fit snugly – loose areas around the joints are an open invitation for flushing.
Flexibility
Wetsuits for open water swimming should have plenty of stretch around the knees, hips and shoulders. If you can’t raise your arm past your ear, then front crawl is a no-go.
Thickness
Wetsuits come in varying thicknesses for use in different seasons. This is usually displayed as two numbers separated by a slash or colon.
For example, 3:2 suits are among the most popular in the UK. The first figure represents the thickness of the torso (in millimetres) and the second, the thickness of the limbs (also in millimetres). The arms and legs tend to be thinner to allow for greater flexibility.
Buoyancy
Thanks to their thick neoprene build, wetsuits will provide a bit of extra buoyancy. But there’s a touch more to it than that. Wetsuits with thick buoyancy panels on the hips and legs are great for beginners, as they will lift your lower body in the water, placing you in a more powerful position for front crawl.
Stronger, more experienced swimmers, however, may find their legs are lifted too high by these panels. Triathletes are likely to prefer a neutral buoyancy that will allow the legs to rise and fall in the water more naturally.
What thickness wetsuit is best for swimming?
For swimming in Britain, a 2.5mm torso is best suited to tepid summer waters, 3.5 or 4mm will keep you cosy in spring and autumn, and 5mm will help keep the cold at bay in winter (providing there’s not a dusting of snow on the beach).
British Triathlon Federation race rules state that wetsuits must not exceed 5mm in thickness, but don't worry too much about this – most major brands will have taken it into account when manufacturing their wetsuits.
How we test
Our Runner’s World Lab testers took a range of wetsuits out for a series of swims, submerging themselves in ponds, lakes and the sea in the name of research.
They then fed back on each wetsuit's performance, letting us know if they kept them warm and proved flexible enough for a race-winning front crawl.
The best models fitted like a glove and offered plenty of protection from the cold, allowing our testers to stay in the water for longer. They were stretchy enough to let them swim freely, and they didn’t dig in or chafe.
The winning wetsuits that earned our team's seal of approval are stamped with the Runner's World GBs Rachel Joyce second in 2015 Kona Ironman World Championships.
The remaining suits below have been tested and rated by our editors and contributors, all of whom swim in open water regularly and compete in triathlons. Some of these wetsuits are a little more technical – and therefore more expensive – than the wetsuits we tested in the lab, making them better suited to more competitive swimmers and experienced triathletes.

Foam rubber, chloroplene and neoprene lining polyester.
Jodie is our Health and Fitness product tester. She runs tests on a wide variety of products, including gym leggings, walking boots, fitness trackers and more. Jodie has managed the testing for 577 products to date, including working with over 600 panellists.


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