Do You Wear Underwear With Swimming Trunks? (Should You?)


This is a pretty common question among the swimming enthusiasts. Do swimmers wear underwear with swimming trunks? More importantly, should you wear one?

Wearing swim trunks while swimming in a pool is normal. However, most swimmers don’t need to wear underwear underneath swimwear or trunks, but in cases when the outfit is uncomfortable or see-through, wearing underwear can be helpful.

Are You Supposed to Wear Underwear with Swimming Trunks?

When you decide to go and dive in swimming pools, you should consider swimsuits; it’s not about only men’s swimsuits. Women are also seen wearing swimwear or bikini while running to the beach. 

You don’t need to wear undergarments under a swimming suit, and it would be better if you don’t be overdressed.

However, in some cases, you can wear regular underwear under swim trunks if you want to, though not always, as this will hinder your swimming flexibility. 


For instance, this can be a better choice if you go swimming on the beach, but not while in the pool.

Times You Should Be Wearing Underwear beneath Swimwear

Your clothing should be very wise because you need to cover your body, but you must be careful about the fabrics too. Swimsuits can be worn as a second layer of clothes over your underwear.

When Swim Shorts Are Not Properly Supportive

It is reasonable when you’re not in a swim brief or your swim shorts are not properly supporting your body. Women are more suggested to wear under wear underneath swim trunks; specially a push-up bra is highly recommended.

If the top wear doesn’t have the proper mesh lining to support your chest, you can try a bra under the swim trunks. 

On the other hand, the guys can wear boxers instead of a swim bottoms. The mesh liner near the crotch area of the swim trunks may not be appropriate at times, and that’s when you can think of the alternatives.


When You Are Not Feeling Comfortable with the Outfit

Some female swimmers may feel uncomfortable in swimming underwear. In that case, they can choose to wear panties under board shorts. 

On the contrary, compression shorts are suitable for both males and females uncomfortable with board shorts at the bottom. 

Though wearing underwear can provide extra support, that is against the general swimming rule. You would better choose to wear swim trunks of better features from a renowned or good quality brand.

When the Swimsuit Is See-Through

You can wear a t-shirt with pants while going to the pool when you’re not a professional who’s swimming for sports. It’s better for you when you simply want to swim to have a personal fun time.

Thus, you can swim without swimsuits, and your pair of clothes may not hamper your swimming. However, if your swim trunks are see-through and get revealing after getting in the pool, you can wear underwear like boxers, trunks, or even push-up bras under swimsuits.


When to Wear Which: Swim Trunks vs Underwear?

Many new swimmers don’t understand the difference between swim trunks and underwear. So, in most cases, they think they’re the same. However, in reality, they are not, and they do have some significant differences. Here’re some of the differences between these two:

The Usage

The first thing that differentiates underwear and swimwear is their uses; underwears usually stick to the skin and protect the private body parts from exposure. However, the swimwear can be used as clothing before swimming. Or in other words, underwear is a layer beneath the outer clothes.

Body Covering

Since inner wears are smaller in shape, they cover a small portion of the body. However, swimwear can provide more coverage than underwear, except for bikinis. You may have seen girls wearing revealing bikinis as swimsuits on the beach.

The Manufacture and Use of Raw Materials

Another big difference between swimwear and underwear is manufacturing and raw materials. Wearing underwear should give the user comfort, and that’s why most undergarments are made out of cotton.

These cotton fibers are the most comfortable and also suitable for many users. This is why most renowned brands make cotton underwear.


On the other hand, a company that makes swimming wear must consider many different factors. They have to use mostly synthetic fabric to make swimsuits for convenient and effective swimming.


If you compare them based on their durability, you must keep the latter ahead. This is because non-water undergarments are not supposed to get wet, so their raw materials and fabrics are less durable. However, swimwear is made of more durable fabrics as it is meant for swimming pools.

Different Inner Mesh Lining

The inner mesh lining in a swimsuit and underwear are different; innerwear, especially those of a man, has extra lining with holes. On the other hand, swim wear may also have a lining for protection, but the latest additions are coming without a lining.

Reasons Why You Should Avoid Using Underwear With Bathing Suits As Much As Possible

As mentioned before, underwear beneath swimwear is not suggested if not necessary; here are the reasons why it’s not a good practice.

Swimming Becomes Difficult

The underwear under swim trunks can increase your difficulty because of the fabric. This is because swim trunks absorb less water, but underwear under swim trunks absorbs water more, and increases drag. Thus, you may feel heavy and find it difficult to swim.


A pool filter works like a vacuum, and if you are overdressed, the filter may increase problems during your swim in the pool. 

Moreover, wearing the wrong kind of clothes can absorb water, increasing significant drag during swimming. So, it is highly recommended to wear swim trunks or speedos (not underwear or boxers as it creates an extra layer and weight on the body).

Regular Clothes May Get Ruined

A swimsuit is prepared so that the water can’t ruin it easily; the fabrics get dried easily and don’t react with chlorine. However, if you wear underwear or regular shorts in the pool, the cloth will be spoiled due to the chemical substances present in the pool.

Cleanliness Can Be an Issue

An inner wear may be difficult to clean more than swim trunks, and the problem will increase if you’re forgetful to maintain the cleanliness. Moreover, wearing underwear inside swim trunks may also catch a waterborne skin disease unless you clean them properly. 

On the contrary, your underwear may also make the water dirty if you’re ignorant about its cleanliness.


Not the Right Dress Code

Another reason for avoiding underwear in the pool is the dress code, especially if you’re a competitive swimmer.

So, if you wear underwear under swim shorts or without wearing swim shorts, it may be considered nudity. So, it is better to avoid them and find swim trunks with enough protection and support.