Rash Guard vs Tee Shirt: What Should You Wear Under BJJ Gi?

BJJ is a type of martial art that falls under the category of grappling. BJJ tournaments include  two types of competitions, Gi and No-Gi. Both types of BJJ competitions have their own uniforms and set of regulatory rules.

BJJ competitors usually wear some protective essentials like rashguards, spats, head wears, groin protection, and mouth guards. These protective essentials make the Gi comfortable and ensure smooth mobility.

The meaning of rashguards is clear from its name. The term “rashguard” consists of two words, rash, and guard. That means rash guards are the protection of skin from rashes. BJJ competitors use rashguards to protect them from rashes and friction injuries. 

Some people use common tee shirts or sweatshirts in place of rashguards. But these tee shirts cannot fulfill the requirement of a rashguard. Let’s have a discussion on the use of rash guards and tee shirts.  

Rules for rashguards are different for men and women. These rules also differ in Gi and No-Gi Jiu-Jitsu.

Rashguards are essential in all No-Gi tournaments whether these are under IBJJF or not. The IBJJF rules allow rashguards for men and women. Rashguards of elastic fabric that are long enough to cover the waistband of shorts are recommended. 

In Gi tournaments for men, rashguards are not allowed under IBJJF rules. Tournaments conducted under IBJJF rules do not allow male competitors to wear a rash guard under their Gi. Some organizations allow male competitors to wear a rash guard under the Gi. ADCC made it optional for men to wear rashguards or not.

For the female division, it is mandatory to wear a rashguard or a tight shirt under the Gi. IBJJF and all other organizations have a proper list of rules for female competitors to wear rashguards under their Gis. 

The purpose of a rashguard is to absorb sweat, protect you from friction injuries and keep your body cool. To fulfill this purpose, you must choose a rashguard that contains all these qualities.

Most rashguards are made of a blend of synthetic fibers. Rashguards might consist of spandex, polyester, or nylon material. Spandex is stretchy while polyester has a hydrophobic nature (water-repellent). Polyester made the rashguard breathable by evaporating sweat instead of absorbing it and causing a cooling effect.

Nylon has a flexible texture and excellent strength. Rashguards consisting of polyester and nylon have all the qualities of a good rash guard like strength, (can not tear) flexibility, and made them breathable.  

On the other hand, most tee shirts are cotton material or a blend of cotton with synthetic material. The cotton used in the tee shirts has absorptive quality. Hence tee shirts absorb sweat. Tee shirts are loose as compared to rashguards.

During training, the rashguard is optional for BJJ practitioners. Various practitioners opt to wear rashguards under their Gi while others do not. Let’s have a discussion on the benefits of wearing rashguards under the Gi.

If you are sweat-free and dry, everybody wants to spar with you. Sweat cannot be avoided during training and fighting. Fighters who have hairy and sweaty chest risk the hygiene of their opponent.

Nobody wants to spar or roll with you if they are expecting a mount with sweat in their eyes and face. Rashguard is very helpful to ensure a hygienic fight between two partners and competitors.

During grappling, both competitors are too close and they have to strangle, grab, mount, or choke each other. During the fight, the Gi does not remain in its place and the fighter does not have time to manage it again during the fight.

Every fighter should respect his opponent’s hygiene and make sure to not irritate his opponent or risk his hygiene with a sweating body.  

During grappling, sweating is natural. BJJ practitioners do training, sparring, and work out for long hours. All the time they are busy in the gym, their bodies sweat. This continuous sweat can cause a rash or other skin infections.

Furthermore, sweat can also make your opponent feel bad. Rashguards help to evaporate sweat instead of absorbing it and prevent skin infections.    

Rashguards absorb sweat and prevent skin infections. Fungus or other infection-causing microbes grow in moist and wet skin. Furthermore, rashguards prevent skin-to-skin contact between two competitors which is also a skin safety.

Various skin infections spread from contact with the infected skin. So rashguards protect from such types of infection.    

During fights, practitioners can become irritated from the sweat running on their faces, palms, or eyes. This running sweat can also affect their performance. Nylon and polyester are fabrics that do not allow sweat to absorb or stay on the skin.

These are water-repellent materials. These fabrics cause water repulsion and evaporate sweat from the skin. This evaporation causes a cooling effect and ensures dry skin. This cooling effect also reduces the effects of excessive sweating. 

Rashguards help to keep your Gi clean and long-lasting. Gi is mostly made up of cotton. Cotton material absorbs sweat and its fabrics start to wither. Rashguard keeps your Gi sweat-free and clean. Another advantage of rashguard is the longevity of Gi.   

Due to the light, compressive and tight nature of rashguards, rashguards provide support to muscles. Rashguards are elastic and flexible in nature. This flexible nature of rashguards works like a brace for the whole body.

Tight rashguards slightly compress the muscles of the body. This compression of muscles holds them together and avoids injuries. Furthermore, rashguards and spats also support the body's joints, muscles, and core.  

Some competitors wear a tee shirt instead of using a rash guard. Tee shirts instead of rashguards are very comfortable. People who cannot wear very tight rashguards can also use their casual tee shirts during training.

But some gyms are very strict with their rules about hygiene. Such gyms make their students compulsory to wear something under the Gi, whether it is a rashguard or a tee shirt.

Beginners who have just started their BJJ journey are not very comfortable with a tight rashguard. A tee shirt is a good option for them. 

Tee shirts also ensure Gi longevity by absorbing sweat. When sweat will be absorbed in tee shirts, it will keep Gi clean and long-lasting.

Rashguards and tee shirts both can be used under the Gi. But rashguards are very much effective as compared to tee shirts. Let's discuss some points which clarify why rashguards are better than tee shirts.

• Rashguards are made of polyester or nylon material while Tee shirts are made up of cotton. So rashguards not only absorb sweat but also cause the evaporating and cooling effect. On the other side, tee shirts absorb sweat and can cause bacterial or fungal growth and various skin infections.
• Rashguards are effective to protect the body against hair friction or mat fraction while tee shirts do not have such qualities.
• Rashguards are tight and compressive. They work like a brace and give support to body muscles and joints. While tee shirts are not compressive in nature.
• Rashguards are also able to cause cooling effects and avoid overheating of the body. While tee shirts absorb all the sweat and give a bad odor instead of giving a cooling effect.
• Rashguards help to keep the body dry while tee shirts absorb sweat and give a wet appearance. Nobody wants to spar and roll with a person having a wet body. 

Rashguards and tee shirts are used for training. Although tee shirts are comfortable, rashguards give the best results. They are helpful to keep the body organized, compressing muscles, giving support to joints and muscles, producing a cooling effect, and preventing skin infections.

Rashguards evaporate sweat and help to prevent any skin infection. Ensure hygiene in a fight, rashguards play a crucial role.

Photo Credit: @caioterrabjj