Brazilian jiu-jitsu is hard work when you train and compete, and all that effort means you sweat even harder. What you wear underneath your BJJ gi affects your performance on the mat. Getting your under-gi wear right helps you perform with more confidence and is best for good hygiene. 

If you're a beginner, you may have questions about what to wear under a BJJ gi (beginners always need guidance on choosing the right gear for their first classes). We've written this guide on what to wear under your BJJ gi to help you stay cool, dry, and ultimately, focused when you're rolling on the mat.

Key Takeaways

• Wear a rash guard under your gi; it helps with sweat control, skin protection, and reduces your risk of infections.
• Choose compression shorts or pants over cotton underwear to prevent chafing and stay comfortable during rolls.
• For women, sports bras and compression tops provide support and compliance with IBJJF rules.
• Athletic shorts are a solid option for no-gi training, but they must be BJJ-specific (no pockets, no zippers).
• Train in clean gear to respect your training partners and protect your skin.

Ultralight 2.0 Jiu Jitsu Gi in White

The BJJ Gi

The BJJ gi is also called a kimono. It's the standard uniform for men, women, and kids, for both training and competition. Our men's kimonos and women's kimonos are designed to give you the right balance of comfort and protection. A well-designed gi also prevents mat burns and supports a better performance.

Women wear compression tops and sports bras for compliance with IBJJF rules, comfort, and safety. Men and women have several options for under-gi wear that offer support and hygiene when you're training.

Roots Rashguard

Rash Guards: The Gold Standard for Under-Gi Wear

Many BJJ practitioners wear rash guards underneath their gis. Yes, they can be worn on no-gi days, but we also recommend them for under-gi wear.

Rashguards are made from lightweight fabric and allow for unrestricted movement, so they're effective for grappling. Rashguards dry faster than shirts made from cotton material, and they are more durable. Wearing the right layers under your gi can make a difference to your performance.

Rash guards offer:

• Moisture-wicking fabric that pulls sweat away from your skin
• Spandex helps keep your body dry and cool during intense training sessions
• Compression, which keeps your muscles warm and reduces fatigue
• Skin protection against mat burns and gi friction
• A layer of defense against skin infections such as ringworm and staph
• Better protection against rashes and skin irritation compared to regular shirts

You can get short-sleeve and long-sleeve rash guards for different training environments. Some BJJ practitioners like the protection of long sleeves, and others find short sleeves to be cooler and more breathable.

Those experimenting with their under-gi wear can look into men’s and women’s rash guards that match the demands of their sessions.

Kore women’s grappling spats

Gi Pants and What Goes Underneath

Your gi pants need to be tough and paired with the right underlayer.

You can wear:

• Compression pants or leggings (also called compression spats or tights) for full coverage, support, and protection against skin irritation.
• Compression shorts for a lighter feel
• Athletic shorts, if you prefer a looser fit

Wearing the right layers under your gi pants helps avoid discomfort and provides better protection during training.

Avoid wearing regular underwear or loose-fitting shorts underneath your gi pants. They can ride up, cause friction, and make you uncomfortable mid-roll.

Compression Shorts and Pants: A Must-Have Layer

Below the belt, compression gear is your best friend. Regular cotton underwear doesn't work because it absorbs sweat and bunches up during rolls. Rather wear:

• Compression shorts to prevent chafing and keep everything in place
• Compression pants (spats) to give you full-leg coverage, added muscle support, and less mat burn
• Leggings (compression spats) are popular with grapplers who want full-leg coverage, support, and skin protection
• Wear shorts under your gi if you prefer a looser fit, but make sure they are designed for BJJ so they’re comfortable and durable

Wearing moisture-wicking, breathable compression gear helps you regulate your temperature and protects you against skin irritation.

If you’re in the market for compression gear, our BJJ women's compression shorts are an excellent choice for comfort and hygiene.

Men's born to rule shorts

Athletic Shorts for No-Gi Training

Many athletes wear BJJ-specific athletic shorts for no-gi classes. These shorts are lightweight, so they're comfortable in hot weather and intense sparring sessions. These are different from regular gym shorts because:

• They don’t have pockets or zippers (which are dangerous in grappling)
• They offer a fitted and flexible shape that doesn’t restrict your movement
• They are designed to stay put during intense scrambles

You can wear them layered over compression shorts for extra support. Don't wear baggy basketball shorts or anything cotton-based, as that gear can absorb sweat and restrict movement.

Our men's BJJ shorts and women's grappling shorts give you flexibility and style.

What About Underwear?

Yes, you should definitely wear underwear with your gi. 

Compression underwear is the most practical. It helps with:

• Sweat control
• Preventing chafing
• Maintaining hygiene

Don't wear boxers or cotton briefs. They trap moisture and can lead to discomfort or even skin infections during long training sessions. Choose something breathable and snug.

Training Smarter: Hygiene, Comfort, and Culture

Keep your BJJ gear clean. Show up in clean, dry clothes and wash your rash guards and compression gear after every class. Keep your hygiene on point as a sign of respect to your training partners.

Also, think about your training environment and adjust your layers as you need to. Is your gym air-conditioned, or are you rolling in the heat? In hotter gyms, short-sleeve rash guards and shorts under your gi may be ideal to keep your body cool and dry. In colder settings, longer sleeves and spats might be better. Choose heat-resistant and moisture-wicking materials.

Get the Right Gear

Now that you know what to wear under your BJJ gi, gear up the right way. Whether you train in a rash guard and compression shorts or go full spats and long sleeve mode, your under-gi setup should keep you dry, comfortable, and focused. Check out our full range of BJJ gear to upgrade your training experience.