How Should Muay Thai Shorts Fit? A Fighter’s Guide to Fit, Movement & Comfort

The simple answer: Muay Thai shorts should fit securely around your waist while staying loose and unrestricted around your thighs and hips. You should be able to kick, knee, clinch and move through your full range of motion without the shorts pulling or needing adjusted.

If you’ve ever trained in the wrong pair of shorts, you’ll know about it pretty quickly.

A waistband digging into you during rounds. Material catching when you throw a high kick. Shorts riding up in the clinch. Or a fit that’s so loose you’re adjusting it between combinations.

In Muay Thai, your shorts aren’t just part of the look. They’re training equipment.

But there’s a bit more to getting the fit right.

At BFAST, we’ve spent years training and fighting in Muay Thai. The brand itself came from wanting fightwear that felt better to actually train in.

Here’s what myself (Niall) and Garrett would look for.

How Are Muay Thai Shorts Supposed to Fit?

A good pair of Muay Thai shorts should feel secure without feeling restrictive.

Unlike running shorts or standard gym shorts, you’re not just moving forwards and backwards. You’re throwing kicks, checking kicks, driving knees, working in the clinch and constantly rotating through your hips.

That means you need freedom around the legs.

Your shorts should give you enough room to comfortably lift your knee towards your chest and throw a high kick without feeling the fabric tighten across your thigh.

At the same time, they shouldn’t feel like they’re falling off.

Think:

Secure at the waist. Free everywhere else.

That’s the balance you’re looking for.

1. The Waistband Should Be Secure, Not Restrictive

The waistband is one of the first things you’ll notice when trying on Muay Thai shorts.

It needs to hold the shorts in place through hard rounds without digging into your stomach.

If you’re constantly pulling your shorts back up during padwork, they’re probably too big.

If the waistband feels uncomfortable before you’ve even started training, they’re probably too small.

Remember that comfort standing in front of a mirror isn’t the same as comfort after five rounds of pads.

Move around.

Bring your knees up. Twist through your hips. Sit into your stance. Throw a few kicks if you’ve got the space.

The waistband should stay in place without becoming something you’re thinking about.

Garrett says ‘Good fightwear disappears once training starts’

2. You Need Room Through the Thighs

This is arguably more important in Muay Thai than in most other sports.

Kicking requires a large range of movement through the hips and legs. Your shorts shouldn’t fight against that movement.

Try raising your knee as high as you comfortably can.

Then mimic a roundhouse kick.

If you immediately feel the shorts pulling tightly across your thighs, the fit or cut may be too restrictive.

Side splits in traditional Muay Thai shorts exist for a reason: they help create the freedom needed for kicking and kneeing.

Whatever style of shorts you choose, mobility should come before appearance.

They can look unbelievable, but if you’re fighting the shorts every time you throw a kick, they’re the wrong shorts.

3. How Long Should Muay Thai Shorts Be?

Muay Thai shorts are traditionally shorter than boxing shorts and most general gym shorts.

Again, that’s about movement.

A shorter cut leaves more of the thigh unrestricted and makes it easier to kick, knee and move freely.

Exactly how short you go comes down partly to personal preference.

Some fighters prefer a traditional high-cut Thai style. Others want a slightly more modern fit that still gives them complete freedom of movement.

There’s no rule saying everyone has to wear exactly the same cut.

The important question is:

Can you move properly in them?

If the answer is yes, you’re on the right track.

4. Should Muay Thai Shorts Be Tight or Loose?

Muay Thai shorts should generally be loose around the legs but secure around the waist.

I think they fit like compression shorts.

Tight material around the thighs can restrict movement, particularly when you’re throwing high kicks or knees.

Going too loose isn’t ideal either.

Excess material can move around unnecessarily, bunch up or simply become annoying during harder sessions.

You want enough space for movement without feeling like you’re swimming in them.

5. Test Your Shorts Like a Fighter

Don’t judge fightwear by standing still.

This is one of the simplest mistakes people make when buying Muay Thai shorts.

They try them on, look in the mirror and decide they fit.

Instead, take them for a quick spin around the house, shadow boxing in the kitchen like every teenage boy does at some stage in his life.

Try:

• Bringing both knees towards your chest
• Throwing a few controlled roundhouse kicks
• Lifting your leg as if checking a kick
• Sitting into your fighting stance
• Rotating your hips
• Mimicking knees from the clinch

Pay attention to where you feel tension, especially around the thighs.

If the waistband stays secure and nothing restricts your hips or thighs, that’s a much better indication of a proper fit.

Why Fit Matters More Than You Think

Small distractions become big distractions when you’re tired, especially when you’re sparring or fighting for your life in round 5 on pads.

During the first round, slightly uncomfortable shorts might not bother you.

After hard pads, clinching or sparring, they will.

You’re already thinking about your breathing, technique, defence, timing and whatever your coach is shouting from the side.

The last thing you need is another distraction.

Fightwear should let you concentrate on fighting.

That’s one of the reasons BFAST exists in the first place.

We’re two Belfast fighters who started training Muay Thai together at 15. After years of training and fighting, we wanted shorts that reflected how we actually wanted fightwear to feel and look.

Built by fighters. Worn by fighters.

Not designed from the outside looking in.

Traditional vs Modern Muay Thai Shorts

There’s more choice in Muay Thai fightwear now than there used to be.

Traditional Thai shorts tend to have a high waistband, wide legs, short cut and prominent side openings.

I personally feel like I’m wearing a nappy when I put on traditional Muay Thai shorts.

Modern fight shorts can change the waistband, materials, cut and styling while keeping the mobility fighters need.

Neither style is automatically better.

What matters is whether the shorts work for your training.

Ask yourself:

Can I kick freely?

Can I knee without restriction?

Will these stay secure during clinching?

Would I happily wear these for ten hard rounds?

If the answer to all four is yes, you’ve found the type of fit you need.

What Size Muay Thai Shorts Should I Buy?

Don’t assume your normal clothing size will automatically be your Muay Thai shorts size.

Cuts can vary between brands and styles.

Your best option is always to check the specific brand’s sizing information rather than buying purely from the letter on the label.

If you’re between sizes, think about where the difference matters most.

You need the waistband secure enough to stay in position, but you don’t want to sacrifice movement through your legs.

And when your shorts arrive, don’t just try them on.

Move in them.

That’s the real test.

Can You Wear Muay Thai Shorts for Other Training?

Absolutely.

A good pair of fight shorts can work well for padwork, bagwork, sparring, MMA striking, conditioning and other training where freedom of movement matters.

BFAST shorts have also been worn beyond Muay Thai, including in MMA and boxing.

The principle remains the same: your clothing should allow you to move without becoming a distraction.

For fighters, that versatility is useful.

You shouldn’t need to think about your shorts once the session starts.

The BFAST Approach to Fightwear

BFAST started in Belfast because we wanted something different from the fightwear we were training in.

We wanted shorts built around movement, durability and modern fight culture — gear we’d actually want to train and fight in ourselves.

Belfast has always had fighting in it.

BFAST is our way of carrying that identity into gyms and arenas further afield.

Whether you’re preparing for a fight or walking into your first Muay Thai session, the principle doesn’t change:

Wear something that lets you move. Then get to work.

FAQs

How should Muay Thai shorts fit?

Muay Thai shorts should fit securely around your waist while remaining loose enough around your thighs and hips for unrestricted kicking and kneeing. They shouldn’t slide down, dig into your waist or tighten across your legs when you kick.

Are Muay Thai shorts supposed to be short?

Traditionally, yes. Muay Thai shorts are usually shorter than standard gym or boxing shorts because the shorter cut gives the legs greater freedom of movement when kicking and kneeing.

Should I size up in Muay Thai shorts?

Not automatically. Sizing and cuts differ between brands, so check the specific sizing information before ordering. The best size should keep the waistband secure while allowing full movement through your hips and thighs.

Can beginners wear Muay Thai shorts?

Of course. You don’t need to be a fighter or have years of experience to wear Muay Thai shorts. If you’re training Muay Thai, they’re designed for exactly the movements you’re learning.

Can I use Muay Thai shorts for MMA or gym training?

Yes. Fight shorts that offer good mobility can work for striking, bagwork, conditioning and certain types of gym training. The key is choosing shorts that stay secure and don’t restrict your movement.

What should I look for when buying Muay Thai shorts?

Prioritise fit, freedom of movement, durability and comfort. Make sure the waistband is secure and check that you can kick, knee and rotate your hips without the material restricting you.

Find Your Fightwear

The right Muay Thai shorts won’t improve your technique overnight.

But the wrong ones can definitely get in the way of it.

Choose a fit that stays secure, gives your legs room to move and lets you forget about what you’re wearing once the bell goes.

That’s how fightwear should work.

If you’re looking for fightwear designed from inside the sport, explore the BFAST Muay Thai Shorts collection and find the pair that fits your training.

BFAST — Belfast born. Built by fighters. Worn by fighters.