When Should You Wear a Rash Guard?

by Adrian Davis April 09, 2025

A rash guard is a versatile piece of athletic wear that serves multiple purposes in various sports, including Brazilian Jiu-Jitsu (BJJ), mixed martial arts (MMA), surfing, and general training. Knowing when to wear a rash guard can enhance your performance, comfort, and safety. Here’s a breakdown of when and why to wear a rash guard:

1. During BJJ and Grappling Training:

No-Gi Training: Rash guards are essential for No-Gi BJJ to minimize friction burns, prevent skin infections, and wick away sweat.
Gi Training: Wearing a rash guard under the Gi helps reduce chafing, adds a layer of protection, and prevents the spread of bacteria.
Competition: In most No-Gi competitions, wearing a ranked rash guard (based on belt color) is required by organizations like the IBJJF.

2. For MMA Training:

Rash guards are commonly worn during MMA training for sparring, grappling, and striking drills.
They help reduce skin-to-skin contact, minimizing the risk of infections like ringworm or staph.

3. Surfing and Watersports:

Rash guards protect against sunburn, jellyfish stings, and abrasions from sand or surfboards.
They provide insulation in cooler waters and UV protection in sunny conditions.

4. Strength Training and Fitness Workouts:

Rash guards can be worn during strength training, CrossFit, or general workouts for moisture control and muscle compression.
Compression features can help support muscles, reduce fatigue, and aid in quicker recovery.

5. Under Gi or Training Clothes:

Some athletes prefer wearing a rash guard under their Gi or workout clothes for added comfort, modesty, and protection.
It prevents the Gi from irritating the skin and keeps sweat from soaking into the Gi jacket.

6. For Skin Protection:

Rash guards protect the skin from cuts, scrapes, and mat burns during intense training or competition.
They help reduce the spread of bacterial infections, especially in shared training environments.

When Not to Wear a Rash Guard:

In traditional Gi competitions where rash guards are not allowed under the jacket.
If a training environment explicitly prohibits them.

Conclusion:

Wear a rash guard whenever you need skin protection, moisture control, compression support, or additional warmth. They are especially valuable for BJJ, MMA, and watersports but can also be a great addition to general athletic training.