Rashguards first became popular among surfers. The tight-fitting spandex/lycra attire stands as a better alternative than your T-shirt both in the water and on the mats. Most people wear rashguards when they are doing NoGi or even when they are wearing gi. John Danaher even treats his rashguard as his daily attire. Once you have found your new favourite rashie, the most important thing is getting the size right.
Yes, John Dannaher literally wears a rashguard everywhere.Why Wear Rashguards For Grappling?
These days, academies are more professional and are catering to the “less hardcore” crowd. Gone are the days where you get training partners who don’t wash their dingy gis. The Mendes Brothers’ AOJ is a perfect example of the modern professional academy. All white and spotless, these are the types of academies that have strict regulations when it comes to hygiene.
Part of maintaining hygiene within the academy is by requiring students to have their rashguard underneath their gi. Some academies even require long sleeve rashguards over short-sleeved rashguards to have better coverage for the rest of the arms. Compared to shirts, rashguards have moisture-wicking properties. It gets rid of sweat instead of having moisture to accumulate in the garment.
Since jiujitsu, MMA, wrestling, and other grappling sports require skin to skin contact, it is important to have a layer of protection to prevent the spread of skin conditions. Staph infection and fungal infection are some of the things that you can avoid when you wear a rashguard and even spats.
Choosing the Right Size

What size should you be getting? According to the IBJJF rulebook, the only thing that pertains to sizing is that the rashguard should be long enough to cover the entire torso. It should be long enough to reach your shorts.
When buying a rashguard, it matters to consider different factors. First, you want to consider your preference. Do you prefer something that’s extra tight-fitting? Or perhaps, you want something a bit loose to give you some room to gain weight or maybe bulk up? Next, you need to consider the sizing of the company. Do they run their sizes small? Perhaps, they run their sizes a bit large?
If you prefer a tight fit, it’s a good idea to stick to the same size that you typically buy on your shirt. If you wear a medium-sized shirt, then go for a medium-sized rashguard. However, there is an exception to this rule. If you are buying from brands that run their sizes small, then you’d want to go up in size. If you wear medium shirts, then it might be a good idea to go for a large.
Why Choose Something a Bit Bigger?
There are jiujitsu practitioners who prefer to have something a bit loose. Some feel rashguards are too restricting for their mobility making it difficult to do scrambles and perform during rolls. If this is the case, you’d want to pick something that is one size larger. Or better yet, why not choose a brand that runs their sizes larger than your average rashguard? Manto is an example of this brand. Manto’s medium rashguard feels like a large rashguard giving you the mobility that you need.
Another reason to consider getting a larger size rashguard is for people that have large necks. If you are the bulky guy with a neck the size of a tree trunk, it might be wise to choose something larger. This prevents you from getting squeezed by the material on your neck.
Buying Women’s Rashguards
Despite rashguards having a larger market for women in jiujitsu, it used to be difficult to find the right sizing for them given the fact that the cut used to be designed for men. These days, brands have catered specifically to female grapplers improving their rashguard’s cut. Women’s rashguards tend to be narrower than your typical men’s rashguard. This makes it easier for women to have a rashguard that has a better fit for their bodies.
Checking the size chart
You also want to check the size chart provided by the brand. Though most brands are true to size, a size chart can give you an concrete idea whether their rashguard is just the right size for you or not.
Brands usually give the chest measurement as well as the torso length in their size chart. This way, you’ll also know if the rashguard is going to cover the entire torso. As for the chest circumference, it usually comes in at 2”-4″ increments before switching to size.
If you are still in doubt, you can ask the brand what they recommend for you. You can even inquire about the height and the weight of the model used on their rashguard to have a better idea.