What to Wear Under a Gi When Training Jiu-Jitsu

If you’re new to training jiu-jitsu with a gi, you’ll be pleased to know that there is plenty of information online about how to find a gi that fits properly and works well for you. However, you’ll still likely wonder what to wear under your gi during your jiu-jitsu training sessions.

Jiu-jitsu gis comes with two primary components – the gi jacket and the gi pants. Most practitioners wear at least one layer of clothing under each of these items. Here are a few common options.

Clothing options to wear under a gi jacket:

• T-shirt

• Compression shirt

• Rash guard

Clothing options to wear under gi pants:

• Underwear

• Compression shorts

• Athletic shorts

• Spats (tight-fitting leggings)

Wearing the right clothes under your gi comes with a few benefits, and each clothing option has advantages and disadvantages. In the sections below, we’ll explore those topics so that you can feel comfortable and confident in your clothing choices during your gi training.

Why is it Important to Wear Clothing Under Your Gi?

We’ll begin by covering why it’s essential to wear clothing under your gi in the first place. While the reasoning may seem obvious, there are a few key benefits that you might not initially expect:

1. Reduced skin irritation: The interior fabric and seams of a jiu-jitsu gi can be rough. During the rigors of training, it’s easy for these materials to cause abrasions, rashes, and irritation when they rub against bare skin.

2. Protection for the gi itself: It’s a virtual inevitability that you’ll sweat at some point during your gi training. A layer of clothing will absorb some of the sweat before it reaches your gi. Thanks to that absorption, it will be easier to clean your gi after training, which contributes to its overall freshness and longevity.

3. Bodily coverage when your gi moves: During jiu-jitsu training, it’s common for your gi jacket to open or shift out of place. A layer of clothing under your gi ensures you won’t need to worry about accidentally exposing yourself while you train.

4. Lower infection risk: Unfortunately, skin infections are relatively common in jiu-jitsu and other martial arts. Thankfully, some clothing options, like rash guards and spats, can lower your skin infection risk.

What to Wear Under a Gi Jacket

Now that you know why it’s beneficial to wear clothes under your gi, let’s discuss a few of the most common clothing options. Each of the upper-body garments in the sections below will come with both upsides and downsides that you should understand.

Wearing a T-Shirt Under Your Gi Jacket

Advantages: A T-shirt is the simplest option to wear under a gi jacket. Standard cotton T-shirts, or any other type of T-shirt you’d wear for a workout, will work just fine. T-shirts are affordable, and it’s safe to assume you likely have at least one viable option in your wardrobe already. If you want the quickest and easiest clothing item to wear under a gi jacket, wearing a T-shirt is the ideal option for you.

Disadvantages: The main downside to wearing a T-shirt under your gi jacket is that most T-shirts are not form-fitting. While a shirt that’s relatively loose is an acceptable option, it’s possible for it to get twisted and tangled during training. This twisting and tangling won’t prevent you from training in any way, but it can be uncomfortable and will cause your T-shirt to wear out faster than it otherwise would.

Wearing a Rash guard or Compression Shirt Under Your Gi Jacket

Advantages: Rash guards and compression shirts are form-fitting, which means they are unlikely to move during training. Additionally, long-sleeved versions of these garments can help reduce the risk of skin infections. The added coverage long sleeves provide makes it less likely you’ll get a cut or skin break, both of which increase the odds of contracting a skin infection.

Disadvantages: Compared to a T-shirt, rash guards, and compression shirts tend to be more expensive. Additionally, long-sleeved versions can make you feel hotter while you train.

What’s the Difference Between a Rash Guard and a Compression Shirt?

We’ve grouped these two clothing options because they are incredibly similar to one another. Still, there are some subtle differences between rash guards and compression shirts.

Overall, rash guards tend to have designs specific to their intended purpose. For instance, a quality jiu-jitsu rash guard will balance lightweight breathability with enough durability to withstand intense training sessions.

By contrast, the design of a compression shirt is more suited for generalized athletic activity. While compression shirts are form-fitting, they won’t always have the breathability and durability that a jiu-jitsu-specific rash guard can offer.

As you might expect, jiu-jitsu rash guards tend to be more expensive than general compression shirts. Still, both options are worth your consideration when shopping for something to wear under your jiu-jitsu gi jacket.

Is it OK to Wear Nothing Under Your Gi Jacket?

If you’ve spent time training or watching jiu-jitsu, you may have noticed that some practitioners choose to wear nothing at all under their gi jackets. Going bare-chested during gi training can help you avoid overheating, but it does come with some significant downsides.

First, as we’ve emphasized so far, wearing a gi jacket without a shirt leaves your skin exposed to the rough inner surfaces of your gi. This exposure often leads to rashes and irritation.

However, what’s more important to consider is that not all your training partners will want to grapple with a bare-chested training partner. In fact, many people consider wearing nothing under your gi jacket to be an unsanitary and unwelcome approach to training.

It’s true that certain unsavory aspects of jiu-jitsu are unavoidable, to a degree. However, wearing a shirt or rash guard under your gi jacket can make the training experience a bit cleaner and more enjoyable for everyone involved.  

Comfort and safety are two of the most influential aspects of creating and maintaining a welcoming training environment. As such, it’s vital to gauge the culture of your gym and the opinions of your training partners before you decide to grapple without wearing something under your gi jacket. When in doubt, wearing clothing under your gi jacket is the correct decision.

What to Wear Under Gi Pants

Although we went into detail describing the advantages and disadvantages of upper-body clothing options, doing so here is not as necessary. Simply put, many of the pros and cons we mentioned above apply to the clothing you wear under your gi pants as well.

Primarily, clothing options that are looser are more likely to get tangled under your gi pants while you train, while form-fitting garments are unlikely to present that problem. For example, boxers and loose-fitting athletic shorts are more likely to tangle than compression shorts.

Ultimately, what you choose to wear under your gi pants is a private matter, but what’s important is that you wear something. Again, the interior fabric and seams of a gi can be rough on your skin. This factor is especially relevant to the sensitive bodily areas your gi pants are responsible for covering.

Also, it’s worth noting that, unlike your gi jacket, it’s far less common for your gi pants to move out of place while training. Still, some shifting and movement is possible. Due to that fact, and the skin irritation gi pant fabric can cause, you should always wear at least one layer of clothing under your gi pants.

What Are Spats?

At the beginning of this article, we listed the primary clothing options you can wear under gi pants. Chances are that you are familiar with all those options except for one.

Spats are essentially the lower-body version of a jiu-jitsu rash guard. A typical pair of spats covers your legs from ankle to hip, and high-quality versions made for jiu-jitsu training will be both breathable and durable.

Like a long-sleeved rash guard, spats provide greater skin coverage, reducing the risk of cuts and the infections they can lead to. Likewise, the potential downside to spats is that they can also make you feel hotter during gi training like a long-sleeved rash guard would.

Despite the potential for overheating, both spats and rash guards remain some of the most prevalent apparel options to wear under a gi. These garments are also incredibly popular for no-gi training, which adds to their value as components of your jiu-jitsu gear set.

What About Wearing a Bra Under a Gi Jacket?

If you’re used to wearing a sports bra while exercising, there’s no reason why you can’t wear one while training jiu-jitsu in a gi.

However, when choosing a bra, it is best to choose one that does not include any hard or sharp components, such as an underwire. These components can increase the risk of cuts and bruising for both you and your training partners.

Lastly, some practitioners choose to wear a sports bra and nothing else under their gi jacket. This approach requires considerations similar to what we described above in the section about wearing nothing under your gi jacket. Again, when in doubt, wearing a layer of clothing over your bra is the wisest choice.

What Should You Wear Under a Gi for a Jiu-Jitsu Competition?

During training, you’ll have more flexibility over what to wear under your gi. However, in competitions, there may be specific rules about which clothing options are allowed. The best way to know what to wear under your gi before a competition is to review the competition rules and regulations.

Some competitions make it illegal to wear nothing under your gi jacket, while others may specify the type of shirt you must wear. Rules about what to wear under your gi pants are less prevalent, but it is generally assumed that you’ll wear at least a pair of underwear or shorts.

Still Not Sure What to Wear Under Your Gi While Training?

If you remain unsure about what to wear under your gi for your first training session, the best approach is to simply ask a coach at the gym where you plan to train. While it may seem like an awkward question, the right coach will be more than happy to provide you with all the information you need to have a comfortable and rewarding training experience.