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Lined vs Unlined Shorts: Do You Wear Underwear or Not?

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Before lined shorts showed up, unlined shorts were the common sight. You’d just put on some underwear, wear the shorts, and get your day going. But now, with lined shorts, it’s more complicated. Lined vs unlined shorts?

So, do you wear underwear or not? There are so many opinions lying around and everyone speaks from their point of view. Now that new contenders, the lined shorts, have come to exist, the debate is rising about whether it’s still needed to wear underwear with them. Compression-type shorts have also come to exist. With the appearance of those, compressive liners came along as well.

To avoid the confusing opinions, we’ll put lined vs unlined shorts in a head-to-head fight with science as our referee. Our main focus would be to scientifically find out whether you should or shouldn’t wear underwear with different types of shorts.

We’ll discuss how wearing underwear in different types of shorts could affect your underlying skin and organs. However, before we begin, it would be worth knowing the difference between lined, unlined shorts, and compressive shorts. Lined shorts are those that have a built-in lining of moisture-absorbing fabric. Unlined ones are the conventional shorts that don’t have such a lining.

Compression shorts are shorts made of stretchy materials that wrap your body and lightly compress your muscles. The entire shorts could be of compression type or the compressive material could be used only in the liner. Some people don’t like to wear compression shorts, however, due to some issues with appearance for certain individuals.

Do You Wear Underwear With Lined Shorts

We don’t recommend wearing underwear with lined shorts but some people still find it comfortable to do so. If you do decide to wear underwear, care should be taken to avoid wearing the wrong type of underwear to prevent excessive friction on the skin. This is important if the lined shorts are of the compression type.

Lined shorts are designed to be worn without underwear. The inner liner is usually made of a light material that provides breathing room for your skin. That material prevents moisture, friction, and irritation. The whole point is to prevent a condition known as chafing.

Chafing is a common skin condition among athletes where the combination of friction and moisture causes skin irritation. With time, athletes may develop some skin rash and if left untreated, could cause swelling or even bleeding.

For this reason, if you do decide to wear underwear with lined shorts, you should be very picky about what you select. Cotton and chafe-free underwear are preferred under lined shorts. They still allow for some ventilation, absorb moisture, and aren’t too irritating.

That being said, even the softest of underwear materials would still irritate athletes who run a lot. We strongly recommend not wearing underwear with lined shorts if you’re a runner. You may get away with it if you run short distances at long intervals, but if you’re a marathon runner, wearing underwear with lined shorts will harm your skin.

Let’s not forget to talk about the compression lining of shorts. Compression shorts in general are made to hold the muscles and keep them from swinging too much. The same compression material is now used in lining some shorts.

Wearing underwear with lined shorts of the compression type is a quick recipe for problems. Excessive chafing and skin rash won’t be the only problems you’d have to deal with. You’d even reverse one of the main advantages you get from wearing lined shorts. Allow us to explain.

We’ve mentioned earlier that compressive shorts hold your muscles in place. When muscles don’t move around too much, this improves the blood flow to those muscles and allows you to go on a bit more.

However, wearing underwear gets that compression to an uncomfortable level. It even presses on a major artery in the hips called the Femoral Artery. That would reduce the blood flow to the leg muscles instead of improving it, and may even cause a numbing sensation.

Do You Wear Underwear With Unlined Shorts

Conventional unlined shorts are often worn with underwear. Those shorts are made of strong materials to resist wear and tear but, on the other hand, could cause excessive friction on the underlying organs. Unless the shorts are of the compression type, underwear should be worn with unlined shorts.

Unlined shorts showed up in the market way before the lined ones. They’re straightforward, familiar, and they often get the job done. The common concept was to put on underwear with unlined shorts but people are coming up with different preferences now.

Nowadays, it’s rather common to wear any type of legwear (not just shorts) without any underwear. This is known as “going commando.” While the opinions regarding this matter are mixed, we’ll discuss it from the scientific aspect only.

Tip: Not wearing underwear with unlined shorts is like holding those shorts and constantly rubbing them on the groin area. As you may be guessing now, that’s not good.

Chafing is the first problem you have to deal with. It will be even more apparent in this scenario because of the direct constant irritation. Just walking in unlined pants without underwear is an irritating condition for the underlying skin.

The second and bigger problem you may run into is Jock itch. Jock itch is a fungal infection that could affect any area of the skin, but it usually appears in moist areas that are under constant friction. This condition is a lot more common in males but it can also happen in females. It manifests as a red patchy area(s) around the groin area.

Those red areas are often very itchy. People end up scratching those areas to reduce the sensation but what they accidentally do is help the patches get bigger.

To keep things fair, if you don’t put on underwear with unlined pants but refrain from doing sports in them, you are much less likely to run into the aforementioned problems. The main ingredient in all of those problems is sweat. If most of your activities aren’t too exhausting, you may get away with not wearing underwear with unlined shorts.

“If your unlined shorts are of the compression type, you shouldn’t wear underwear. The underwear would absorb all the sweat and cause your compression shorts to go damp and reduce their breathability.”

Additionally, they cause what’s known as the compression shorts bulge, a condition where your underwear would bulge in certain areas over your underwear.

What Is the Point of Underwear Lining in Running Shorts?

The primary function of underwear lining in shorts is ventilation and muscle holding. The groin area isn’t well-ventilated and sweat accumulates there quickly. Excessive sweat automatically means excessive bacteria which increases the chances of skin problems. The liner serves to hold the muscles and organs in place.

The skin is often covered with various types of bacteria, especially in areas that don’t get cleaned very often. Adding any type of moisturization to such areas won’t only help the bacteria to irritate the skin, but it would also help fungal infections to occur; both of which are scenarios you’d need to avoid.

Underwear lining in shorts serves to keep the friction of the fabric material away from your skin while giving it some room to breathe. The liner is made from a sweat-absorbing material that prevents moisture from stagnating on your skin. The lining is often soft to touch and won’t cause irritating friction to the underlying organs.

That takes care of both the chafing and jock itch problems. The liner also serves to hold the muscles in place which helps the body to provide them with enough blood supply. For men, the organ-holding function of the shorts lining is especially useful in preventing groin pain.

Underwear lining in shorts also helps in preventing dust and dirt from going underneath your shorts. If you tend to sit on the ground after your workout, you may accumulate some dirt in the shorts by accident. Having lined shorts is also helpful for your laundry. You’ll have less to wash after every workout which is helpful in an era where time is money.

Final Words

So, to sum things up in our lined vs unlined shorts battle, do you wear underwear or not? The answer varies depending on the situation. If you prefer the usual unlined shorts, we recommend wearing underwear. It will prevent your organs from moving too much, reduce friction, and absorb sweat.

If you like the lined shorts, we recommend against wearing underwear. Underwear in this case will cause a lot of friction and halt the breathability benefit you’d have otherwise gotten from lined shorts. Finally, compression shorts or compressive liners should be worn without underwear. Not only would they cause friction but they may also reduce the blood supply to your legs.

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About the author

Jasper loves to write about fitness, running, and anything else that gets him moving outdoors. He's an avid hiker, backpacker, and climber who loves to stay fit so he can make sure he's healthy enough to enjoy his favorite hobbies. He also spends time writing about his true passions in life.