Updated 22 Nov 2023.

Many beginners wonder what to wear in a triathlon.

Some know that a triathlon suit is what’s worn, but they still wonder:

• What is a tri suit?
• How necessary is it?
• When should one be worn?

A triathlon suit is Lycra shorts that connect to a top with or without sleeves.

It is worn throughout the entire race preventing any need to change clothes between the swim, bike, or run.

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Do you really need a tri suit?

If you are going to be racing competitively, the answer is yes, you really do need a tri suit.

If you just intend on doing one or two short, non-competitive triathlons for fun, then maybe you don’t need one.

But the vast majority of athletes these days will wear one.

You need a tri suit as it’s a single garment which you can wear from the swim, to the bike, and into the run without changing.

There are not many pieces of clothing that you can comfortably swim in, then bike, then run in.

In the old days of triathlon, athletes used to change clothes, mainly for the run, but nobody does this anymore.

In a triathlon, where every second counts, wearing the same thing throughout just makes sense.

Some of the characteristics of a tri suit may include:

• A lightweight chamois (or pad on your groin) that is typically not made of foam, as foam holds more water than gel-like padding
• A zipper to close it from the belly button to the top of the chest
• Sleeves or no sleeves. Sleeves may offer sun protection, but could chafe in the swim.
• Usually, two to three pockets in the small of the back mainly to hold nutrition (gels or bars), glasses, tools, etc.
• Rubber-coated leg-openings to grip the legs
• Some may have some reflective piping or features for night riding (though most races are not in the night)
• Some may have a gap around the belt line for easy peeing, however while on the bike or run, many athletes pee while riding or running (see links here and here about peeing on the bike and run)
• The groin is generally all black to prevent it from becoming see-through while wet

Top Tri Suits

1. Purpose Hypermesh

For years, I have worn tri suits from Purpose, a brand best suited for hot weather racing.

But don’t take my word for it – this is the tri suit that Dr. Dan Plews wore when he won the IRONMAN World Championships in Kona in 2018.

Purpose tri suits use Hypermesh^TM PRO material which is dimpled allowing for more surface area for drying and evaporation in the heat.

The zipper is a YKK SOFLEX, the chamois is from Elastic Interface Italy, and the fabric is from M.I.T.I. Italy.

There’s a waist-high gap behind where the zipper opens, for easy-access during pee breaks.

The suit has two pockets in the back.

This is my go-to suit, and I’ve worn it in countless races – both half and full Ironmans – with no issues.

Available in 6 sizes, from XS to XXL.

If you would like to get a 10% discount on a Purpose tri suit, enter the promo code IMHACKS at the Purpose site here.

2. Zoot – Men’s Ultra Tri Podium 1 Racesuit

Yo Yo Yo!

If you’ve been following any pro triathletes at all you’ll know that’s Sam Long’s callout, and you’ve probably seen his distinctive Zoot trisuit.

Born and bred in Kona, Zoot has been around for a while so you know you can trust them for quality and crafting.

The Ultra Tri P1 is super lightweight and claims to provide UPF 35+ sun protection with its 4-way stretch, Italian fabric.

Sam Long’s design is called Vice, but there are many other designs of the same suit.

What really stands out, however, is the pockets. Not just the rear side-cut pockets, but the two inside pockets for gels and ice as well as the below-the-neck pocket for ice.

And with a thinner chamois towards the rear (3mm) where you don’t need it when you’re aero, this gives more comfort on the run.

Up front it’s a 6mm pad where it counts, which is perforated high impact foam for support and drainage.

The aero, Italian fabric is wind tunnel tested, which explains the ribbed sleeves and back.

Oh, and did we mention that Ellie Salthouse and Ben Hoffman wear the ULTRA Podium One Racesuit too?

Comes in 5 sizes, XS (28″ waist) to XXL (40″ waist).

3. 2XU Light Speed Front Zip Trisuit

It’s 2 times U, but I never hear anybody call it that, just two ex you.

Either way, this long-established Aussie brand has you covered – literally – when it comes to swim, bike, run attire.

I’d say this is a mid-range brand, but I’ve been able to find a lot of their products on sale, making for really good deals.

I really like the Light Speed Front Zip Trisuit, which is sleeveless and comes in a subtle all-black design.

Though it looks plain, and many athletes want such designs, it’s a full-featured suit.

2XU states they designed it in accordance with RMIT University research on ventilation and cooling.

Also, it sports muscle stabilization, and aero features, with a unique chamois.

They call it the TMF® Light Speed Tri Chamois. It’s made of dual layer 90 density 6mm foam combined with 140 density 3mm foam.

It has what 2XU calls a “free-edge” meaning the external edge of the chamois is without foam, creating a totally flat transition to the suit for max comfort.

Available in three sizes, M (31.5″ waist) to XL (37″ waist).

4. Castelli PR 2 Speed Suit

A staple brand in the cycling industry, Castelli is known for their quality, and that’s a great start.

But the fact that Cam Wurf wore a Castell PR to break the Kona bike record makes it all the better.

With a name like PR, you know it’s fast, and this second iteration has been tested in the wind tunnel. Castelli says it’s “the fastest triathlon racing suit” and indeed, this is the Italian brand’s fastest, most aero option for long-course racing.

The silicone speed ribs on the sleeves are said to reduce drag where it’s needed most (arms), and the sleeves extend nearly to the elbows for added benefit. I like this, however, more for sun protection.

The thin (and maybe fragile?) material will make for a good aero fit, and the two pockets in the back are cut to the side so at to not become underwater parachutes in the swim.

Castelli claim it can deliver comfort and cooling on the run, and that’s in part due to its featherweight mass of only 227 grams.

With seven sizes to choose from – XS (30″ waist) all the way up to 3XL (40.5″ waist).

As a beginner, you may want to do the following to get started:

• Read more tips and tricks to a faster race
• Subscribe to our free weekly newsletter
• Subscribe to our YouTube channel and watch more videos on this awesome sport
• Browse to our Triathlon for Beginners page

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