Wear a rash guard under the gi for hygiene and comfort. Women should also wear a sports bra. Add compression shorts or spats optionally for extra coverage and cleanliness.
For Men: Most male BJJ practitioners wear a rash guard under their gi. BJJ Rash guards help prevent skin irritation, wick away sweat, and add a layer of protection against friction. They also reduce the risk of skin infections like ringworm, especially during intense training. Short or long sleeve comes down to preference—long sleeve offers more skin coverage, while short sleeve feels cooler. Under the gi pants, compression shorts are a solid choice. They keep everything in place and reduce chafing. Some practitioners also wear spats (compression leggings) for added coverage and warmth, especially in colder gyms or during open mats. Wearing a groin protector or cup is a personal choice, but it’s worth noting that most gyms discourage it for rolling. Cups can cause injury to training partners during certain movements. Most practitioners opt for snug-fitting compression gear to minimize movement instead.
For Women: A supportive sports bra is essential. Over that, many choose to wear a rash guard for the same reasons men do—comfort, hygiene, and skin protection. Some rash guards are specifically designed with women’s cuts, offering a better fit and less bunching under the gi. Under the gi pants, women usually wear spats or compression shorts. These provide comfort, prevent transparency issues with lighter gi pants, and offer a modest, functional base layer that holds up during training.
What Not to Wear: Cotton T-shirts soak up sweat, shift around during training, and can get caught when your partner grips your collar. They’re also not very hygienic. Loose underwear or boxers offer no support and tend to bunch up under your gi pants. Regular leggings often aren’t designed to handle the friction or movement of grappling. Stick to spats or compression wear.
Gym Policies and Personal Preference: Some gyms require rash guards under gis for hygiene purposes, while others leave it up to you. Always check your gym’s rules, and even if it’s optional, many seasoned grapplers choose to wear rash guards and compression gear because it simply feels better on the mats.
Final Thoughts: Whether you’re male or female, the goal is the same—stay comfortable, stay clean, and protect your skin. High-quality base layers like rash guards and compression shorts or spats make a huge difference in how you feel during training. Plus, they help your gi last longer by absorbing some of the sweat and stress of daily rolls. Train smart, wear what works, and you’ll feel more confident every time you tie your belt.