Do you need to wear underwear under a tri-suit?

You might feel silly asking it, but the question of whether or not you need to wear underwear under a tri-suit is one that’s likely been pondered by thousands of people before you.

Before getting to the answer, let’s briefly explain what a tri-suit is.

A tri-suit is an single piece of clothing that you can wear through a whole triathlon, including the swim, bike and run.

It tends to be made of lightweight performance fabrics that dry quickly and breathe very well, while there’ll be a chamois bike pad to provide comfort on the bike.

There’s normally a zip at the front and you can get both sleeved and sleeveless options. There are many types of variations, tailoring things for various distances, and you can find out more about these in our list of the best tri-suits.

Should I wear underwear under a tri-suit?

Now that’s out of the way, let’s get down to the nitty gritty and answer the question at hand.

Simply put, nope, you don’t need to wear underwear under a tri-suit.

Your tri-suit won’t come off from the moment you start a race – either under a wetsuit or on its own if the water is warm enough – until you’ve crossed the finish line, so if you want to go commando you’re more than welcome!

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It might feel strange at first, but you’ll soon get used to the skin-tight, stream-lined feel. No underwear also means no potential chafing in those delicate regions.

This will allow you to ride for longer and more often, with less uncomfortable niggles. Use chamois cream along the sensitive areas most prone to chafing to ensure the smoothest possible ride.

Just ensure you wash your bib shorts or suit after each use to avoid build-up of bacteria, which can cause infection.

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Female triathletes should wear a sports bra though, to protect delicate breast tissue while on the run section.

Tri-suits will often have specific support built in, which can be quite handy as you can avoid spending the rest of the race in a soggy bra. However those with larger cup sizes might need the extra support of a good sports bra underneath.

So in short, no pants = no problem.

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