What to Wear Under a BJJ Rash Guard: Men & Women's Guide

Most BJJ practitioners wear compression shorts under a rashguard. What to wear underneath varies by gender, whether you train gi or no-gi, and the gym environment. For men, the best choices to wear under a BJJ rashguard are compression vests, tank tops, tight swim trunks, or compression shorts. Wearing a rash guard alone can provide many benefits, but layering it with the right undergarment is important, especially for martial artists who engage in intense physical activities.

What Men Wear Under a Rashguard BJJ?

For men participating in martial arts or combat sports, wearing the right underlayer beneath a rash guard is essential for comfort and muscle support. Here are the top options:

Options for men to wear under rashguard	Material	Benefits	Best For
Compression Top (Short Sleeve)	Spandex/Polyester Blend	Reduces fatigue, wicks sweat away	BJJ, MMA, Muay Thai
Compression Top (Long Sleeve)	Lycra/Polyester	Full upper body protection	Grappling sports, BJJ
Sleeveless Compression Top	Nylon/Spandex	Keeps core muscles supported	Muay Thai, striking sports
MMA Shirt	Polyester/Nylon Mesh	Manages sweat and provides upper body coverage without the tight compression of a rashguard	MMA, Muay Thai, general training
Compression Vest	Spandex/Polyester	Provides core support with maximum ventilation	MMA, Muay Thai
Sports Boxer Briefs	Polyester/Elastane	Prevents chafing and irritation	All martial arts
Compression Shorts	Spandex/Polyester	Reduces muscle fatigue	BJJ, MMA
Jockstrap with Cup	Nylon/Cotton blend	Provides groin protection	Striking sports, MMA

Compression Tank Top For Protection with Mobility

A compression tank top worn under a rash guard offers additional upper-body muscle support while allowing for a full range of motion. Its sleeveless design ensures it doesn’t interfere with shoulder movements, making it especially beneficial during grappling-heavy sports. The spandex component provides the four-way stretch that grappling demands

Long-Sleeve Compression Top for Full Arm Coverage

A long-sleeve compression top provides full-arm coverage while supporting upper-body and arms muscle groups. This option is ideal for colder gym environments or winter training, offering added warmth and improving muscle efficiency. BJJ practitioners often use long-sleeve tops during intense, lengthy sessions.

Compression Vest Supports Chest and Core

Under a rash guard, the compression vest offers a streamlined fit that supports the chest and core, ensuring full mobility and comfort during intense combat training. The sleeveless design maximizes shoulder flexibility, enabling powerful strikes and dynamic grappling without restriction.

Compression Shorts for High Intensity Workouts

Compression shorts are one of the most popular choices for men in combat sports. They support muscle, reduce fatigue, and improve blood circulation during high-intensity workouts. Compression shorts paired with BJJ rashguards are the standard no-gi kit. These snug-fitting shorts help reduce friction and prevent chafing during grappling, ensuring comfort while training on the mats.

Athletic Underwear

Wearing an athletic cup or jockstrap under a rash guard provides protection for striking-heavy sports like MMA or Muay Thai. Compression shorts with a built-in jockstrap or cup ensure groin safety without adding bulk, making them an excellent choice for combat sports involving kicks and strikes.

What Women Wear Under a Rashguard

For women, a sports bra under the rashguard top and compression shorts or spats under the bottom are the standard choices. The rashguard does not replace the sports bra. The rashguard sits over it.

Sports Bra for Upper Body Support

A high-impact sports bra is the foundation for women training any combat sport. The clinch, takedowns, and ground work place the same demands on a bra as high-impact cardio. The fabric should be moisture-wicking synthetic , polyester, nylon, or spandex, not cotton. A racerback style keeps straps clear of the rashguard’s sleeve area during arm-intensive movements.

Compression Shorts and Spats for the Lower Body

Compression shorts under rashguard shorts are standard; they prevent inner-thigh chafing during guard work and provide fuller coverage in positions like guard, triangle, armbar, where training shorts alone sometimes do not. Full-length spats are the preferred choice for many women in gi class, providing complete leg coverage against the rough gi weave and mat abrasion.

Criteria Checklist for Choosing Undergarments for Your Rashguard

Here’s a checklist to help you choose the right base layer for your martial arts training:

Comfort: Ensure the fabric is smooth and non-abrasive, especially when rolling.
Mobility: Make sure it doesn’t limit your range of motion for kicking, punching, or grappling.
Hygiene: Opt for moisture-wicking and anti-microbial fabrics to reduce the risk of skin infections.
Breathability: Choose lightweight, breathable materials that allow airflow during intense training.
Fit: Tight-fitting options (like compression wear) help prevent bunching and irritation.
Durability: Ensure it can withstand constant washing and grappling wear and tear.

Custom rash guards at Infinitude for men and women are designed with performance, comfort, and style in mind. The premium material is resistant to stretching and tearing, ensuring long-lasting use. Our customized rashguards enhance muscle compression while reducing fatigue during intense training sessions.

Considerations While Choosing What to Wear Under a Rashguard

For maximum comfort and safety during your martial arts training, it’s important to avoid some common mistakes when choosing undergarments. Here are a few to keep in mind:

Wearing Cotton shirts: They absorb moisture, which can cause discomfort and even skin irritation.
Choosing the Wrong Size: Too loose can lead to friction burns, and too tight may restrict movement.
Not Rotating Your Gear: Always have a fresh set of underwear to avoid bad odors and infections.

Final Words

Wearing the right clothing under your rash guard is about comfort and maximizing your performance in martial arts. From providing the right muscle support to protecting your skin from the harshness of training mats, layering smartly under your rash guard can be the difference between a good session and a great one. The choice of what to wear under a rashguard depends on your comfort level, weather conditions, and the type of activity.

FAQs

What if you wear nothing under a rash guard?

While it’s possible to wear nothing under your rash guard, it’s usually not advised in combat sports. Wearing compression gear or a sports bra underneath provides support and helps prevent skin irritation from friction, especially during grappling or striking.

What fabric should underlayers be for rashguard training?

Polyester-spandex blends with around 85-90% polyester offer the right combination of moisture management, stretch, and durability for training.