Nobody warns you about this before your first class, but it is one of the most common things you will run into as you keep training. At some point, most grapplers deal with a skin infection, usually ringworm. It is not a sign you or your gym did something wrong. It is just a reality of a sport built on close, sweaty contact with other people and shared mats.
Here is what actually causes it, how to meaningfully cut your risk, and what to do if it happens anyway.
What Ringworm Actually Is
Despite the name, there is no worm involved. Ringworm is a fungal skin infection, and it shows up as an itchy, red, ring-shaped patch, usually on the arms, legs, or torso, but it can also affect your feet (athlete's foot) or groin (jock itch). It is caused by fungi that thrive specifically in damp, dark environments, which describes a sweaty gi, a rolled-up rashguard, or the inside of a gym bag almost perfectly.
It spreads two ways: direct skin-to-skin contact with someone who has an active infection, or contact with a contaminated surface, gear, mats, towels, that the fungus is living on. Symptoms typically show up four to fourteen days after exposure, so you often will not connect it back to a specific class or training partner.
The good news: it is common, treatable, and rarely serious. The discomfort is the real cost, not any lasting danger.
Why BJJ Specifically Puts You at Risk
This is not a knock on your gym. It comes down to the nature of the sport itself: extended, sweaty, skin-to-skin contact with dozens of different training partners, on mats that see hundreds of people a week. Even a gym with strict cleaning standards cannot fully control what walks in the door, and plenty of people train through a mild infection without even realizing they have one.
That is exactly why your own habits matter more than anything your gym does.
How to Actually Cut Your Risk
None of this is complicated, but it has to be consistent.
- Shower as soon as possible after training. Hot water and soap is genuinely effective on its own. The fungus needs time on your skin to take hold, so the faster you clean it off, the lower your risk.
- If you cannot shower right away, wipe down. I keep this simple: if I cannot shower immediately after training, I wipe myself down with baby wipes. It is not a full replacement for a shower, but it meaningfully cuts your exposure time until you can.
- Wear slides, not flip-flops, in the locker room and shower. Bare feet on a wet gym floor is exactly how athlete's foot spreads. I switched to slides myself, and they hold up far longer than flip-flops too.
- Wash your gear after every single session. I cover the full routine in how to get the smell out of a BJJ rashguard. The same habit that kills odor is what keeps fungus from setting up shop in your gear.
- Do not share towels or gear. Simple, but easy to slip on when you are rushing.
Does a Long Sleeve Rashguard Actually Help?
To a degree, yes. Reducing how much bare skin makes contact with the mat reduces your overall exposure, which is why some people, myself included, hear from customers who specifically choose a long sleeve for this reason. It is not a guarantee. Fungus can still reach uncovered skin or come through a damp sleeve pressed against a contaminated surface. But less exposed skin is still less exposed skin, and I have noticed it tends to be the more experienced, longer-training grapplers who gravitate toward long sleeves, whether that is for this reason or just personal preference after years on the mat.
If you want the extra coverage, we carry a long sleeve rashguard built the same way as the rest of our line. Think of it as one more layer of prevention on top of your actual habits, not a replacement for them.
What to Do If You Get It Anyway
If you notice an itchy, red, ring-shaped patch, do not panic, and do not keep training on it. A few things worth knowing:
- Over-the-counter antifungal creams work for most cases. Products containing clotrimazole, miconazole, or terbinafine are the common active ingredients.
- Athlete's foot usually responds well to antifungal cream or medicated foot powder.
- Stay off the mats while it is active. This is the one non-negotiable. Continuing to train spreads it to your partners and the mats, and prolongs your own infection.
- See a doctor if it does not improve, spreads, or shows up somewhere unusual, like your scalp or face. This article is general information, not a diagnosis, and a doctor can confirm what you are actually dealing with and prescribe something stronger if an over-the-counter option is not cutting it.
A Quick Word on Other Skin Infections
Ringworm is the most common one, but it is not the only one. Staph infections (bacterial, not fungal) can also show up in grappling sports, usually as a painful, pus-filled sore rather than an itchy ring. If you notice something that looks infected, is spreading, or comes with fever, get it looked at by a doctor rather than guessing.
Prevention Checklist
- Shower immediately after training, or wipe down if you truly cannot
- Slides, not bare feet, in the locker room and showers
- Wash gear after every session, no exceptions
- Do not share towels or gear
- Consider a long sleeve rashguard for extra coverage
- Trim your nails so you are not scratching yourself or partners
- Never train through an active infection
Final Word
Skin infections are an unglamorous but normal part of training a contact sport this close and this often. You cannot fully control it, but you can meaningfully stack the odds in your favor with a few consistent habits. Shower fast, wash your gear every time, and give yourself a little extra coverage if you want it.
If you're building out your rotation, our rashguards, including the long sleeve, are built for exactly this kind of daily wear and wash.
Frequently Asked Questions
Is ringworm dangerous?
No, ringworm is rarely serious. It is uncomfortable and contagious, but it is very treatable with over-the-counter antifungal cream, and most cases clear up within a few weeks.
Does a long sleeve rashguard prevent ringworm?
It can reduce your risk by covering more skin, but it is not a guarantee. Consistent showering after training and washing your gear after every session matter more than sleeve length alone.
How long after exposure does ringworm show up?
Typically four to fourteen days after contact, which is why it is often hard to trace back to a specific class or training partner.
Can I still train with ringworm?
No. Training with an active infection spreads it to your partners and the shared mats. Stay off the mats until it has fully cleared.