Brazilian jiu jitsu, or BJJ, is a martial art that focuses on grappling and ground fighting. Traditionally, like many other martial arts, jiu jitsu is practiced in a "gi," or kimono and pants.
However, with the rise in popularity of mixed martial arts, or MMA, the practice and popularity of "no-gi" jiu jitsu, sometimes called submission wrestling, has also increased. Most practitioners of no-gi jiu jitsu wear rash guards, which have several functional benefits.
Since the introduction of MMA in the 1980s, no-gi competitions and training have dramatically increased in popularity. As a result, the International Brazilian Jiu Jitsu Federation, or IBJJF, has begun to hold no-gi competitions, including a world championship. Previously, the IBJJF only held competitions requiring athletes to wear the traditional gi.
A gi consists of a sturdy robe and pants designed specifically for BJJ, along with a colored cloth belt that keeps the robe closed while also indicating the practitioner's rank. While offering a layer of protection, competitors can also use parts of the gi to sweep or submit one another. No-gi BJJ disallows the use of clothing to take down or submit an opponent.
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Composition and Types
The IBJJF requires no-gi competitors to wear a rash guard that denotes their rank, or belt level, in order to compete in tournaments the federation sanctions. Rash guards are usually made of nylon and lycra or spandex. They are designed to fit tightly to the body, while at the same time being stretchy, permitting a full range of motion.
There are several styles for these shirts: T-shirt cut, sleeveless and long sleeve, with the preference depending on the individual athlete. There are many BJJ and MMA branded rash guards, including TapOut, Bad Boy, OTM and Volcan. However, generic active wear or compression shirts made by less-specialized athletic companies like Nike, Under Armour and Reebok provide the same function and benefits.
Generally speaking, rash guards are designed to wick moisture away from the body and help the athlete stay as cool and dry as possible. In addition, rash guards are typically constructed with flatlock stitching, which allows the seam to lie flat to the garment instead of hanging loose from it.
This type of stitching increases garment strength and minimizes discomfort and chafing that can sometimes occur from garments with traditionally stitched seams. Finally, instead of using a conventional four-panel T-shirt construction, rash guards use six panels, which ensures increased mobility, wet or dry.
The main benefit of wearing a rash guard in no-gi jiu jitsu is to help prevent "mat burn." Typically jiu jitsu is practiced on tatamis, or mats made of an extremely durable foam pad with a textured vinyl surface that is waterproof and provides some traction.
The textured surface of the tatami can cause mat burn when exposed areas of skin are pulled or pushed along the mat. While areas like the hands and feet cannot be covered, rash guards can protect the chest, back and arms from the pain of friction-induced mat burn.
Some gyms require participants to wear rash guards during training. However, many gyms still permit regular T-shirts to be worn. T-shirts soak up and retain sweat, are heavy and hot, and can get stretched or torn. They are also easy for an opponent to grab or get tangled up in.
Rash guards are better suited for grappling training, because they are tight-fitting and lightweight, wick sweat away from the skin and help to keep the body cool. They also stretch without tearing and minimize mat burn.