Custom Gym Wear Manufacturer: What USA and UK Fitness Brands Need to Know Before Placing Their First Order

The Gym Wear Market Right Now — Why This Is the Right Time to Launch

The global activewear and gym clothing market crossed $400 billion in revenue in 2025 and is projected to keep climbing through the end of the decade. In the USA and UK, fitness culture has moved well beyond the gym — gym wear is worn at coffee shops, on school runs and at work-from-home desks. It is no longer a niche product category. It is everyday clothing with technical performance credentials.

What this means for brand owners is significant. The demand is there. The customer base — people who exercise regularly and care about how they look while doing it — is large, engaged and willing to spend more than average on clothing they consider functional and identity-defining. The question is no longer whether there is a market for a new gym wear brand. The question is whether you can find a custom gym wear manufacturer who will actually deliver the product quality your brand needs to compete.

That is where most new brands hit their first serious obstacle. This guide exists to help you clear it.

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Understanding Activewear Fabrics — The Decision That Defines Your Product

The fabric is not a detail. For gym wear specifically, the fabric is the product. A customer who buys your leggings and finds them see-through during a squat, or a customer who buys your training top and finds it holds sweat rather than wicking it away, will not come back. More importantly, they will tell people.

Before you contact any private label activewear manufacturer, you need to understand the fabric options well enough to specify what you want. Here is a practical breakdown of the most important choices.

Nylon-Spandex (Nylon/Lycra) — The Premium Choice

This is the fabric that brands like Lululemon and Gymshark built their reputations on. An 80/20 nylon-spandex blend — 80% nylon, 20% spandex — offers exceptional four-way stretch, outstanding durability, a smooth luxurious hand feel and colour retention that holds through hundreds of washes. It is more expensive than polyester alternatives, typically commanding a 20–35% higher unit cost, but the difference in the final product is immediately obvious to the customer who is holding it.

For leggings, sports bras and any tight-fit compression product, nylon-spandex is the benchmark most quality-conscious brands should be working toward. Target GSM: 200–240 for leggings, 180–210 for sports bras.

Polyester-Spandex — The Versatile Mid-Range

An 88/12 or 85/15 polyester-spandex blend is the most widely used fabric in activewear because it balances performance with accessible cost. It is moisture-wicking, dries quickly and holds sublimation print particularly well — which makes it the standard choice for athletic shorts, performance tops and training jerseys. It has slightly less stretch recovery than nylon-spandex and a less premium hand feel, but at 30–40% lower cost per unit, it makes strong commercial sense for most product categories outside of tight-fit leggings.

Cotton-Spandex — For the Lifestyle-Athleisure Category

A 95/5 cotton-spandex blend sits at the crossroads of gym wear and casual clothing. It has a natural hand feel that many customers prefer, comfortable stretch and excellent breathability. What it lacks is the technical performance of nylon — it holds moisture rather than wicking it, which makes it unsuitable for high-intensity training wear but perfectly appropriate for yoga, pilates, walking, and the athleisure category that blurs the line between workout and lifestyle clothing.

Recycled Fabrics — The Growing Demand

REPREVE and similar recycled polyester fabrics — made from post-consumer plastic bottles — have moved from niche to mainstream in the activewear category. Brands like Adidas, Patagonia and H&M have all made public commitments to recycled material integration. For a gym wear brand launching in 2026, particularly one targeting the UK and European market where sustainability values are strong purchase drivers, offering at least one product in a recycled fabric is worth serious consideration.

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What GSM Actually Means — and Why You Should Care

GSM stands for grams per square metre — it is the standard measurement for fabric weight, and it tells you more about a finished garment than almost any other single number. Unfortunately, most new brand owners never ask about it.

For gym wear specifically:

• 160–190 GSM: Lightweight. Good for training tops, running wear and warm-weather products. Breathable but thinner — may require lining for certain applications.
• 200–240 GSM: Mid-weight. The standard range for gym leggings, sports bras and compression shorts. Provides the coverage and recovery most customers expect from performance activewear.
• 250–280 GSM: Heavyweight. Used for yoga pants, pilates wear and athleisure leggings where a premium structured feel is part of the product identity.

When requesting quotes from a custom gym wear manufacturer, always include your target GSM alongside your fabric composition. A manufacturer quoting you on "nylon-spandex leggings" without specifying GSM could produce anything from a sheer 160 GSM fabric to a substantial 250 GSM — and the price difference between those two outcomes is significant.

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Sizing for the USA and UK Markets — Getting This Right Saves You Returns

Sizing is one of the most underestimated aspects of launching a gym wear brand that targets multiple markets. The USA, UK and EU all use different size labelling conventions, and the body proportions that designers use as grading references are not identical between markets.

As a practical starting point, here are the size grades most USA gym wear brands work to:

Size	Waist (inches)	Hip (inches)	Inseam (inches)
XS	24–26"	34–36"	27"
S	27–29"	37–39"	27.5"
M	30–32"	40–42"	28"
L	33–35"	43–45"	28.5"
XL	36–38"	46–48"	29"
XXL	39–41"	49–51"	29"

For UK sizing, the waist and hip measurements are similar but the label numbering is different (UK 8, 10, 12, 14 etc.) and inseam lengths skew slightly longer in general. If you are targeting both markets with the same product, use a dual-label approach or carry size charts in inches and centimetres on your product pages.

At Gloves Storm, we grade all patterns in-house and can work to your specific size chart rather than forcing your product into a standard template. This is important for brands that want to offer extended sizing or who have done their own body measurement research for their target customer base.

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How Gymshark Actually Started — And What It Means for Your Brand

Gymshark is probably the most studied example in the gym wear brand building space — and for good reason. Founded in 2012 by Ben Francis from a garage in Birmingham, UK, the brand scaled to over $500 million in revenue within a decade. What most people who tell that story leave out is the manufacturing side.

Gymshark's early growth was built on finding manufacturing partners who could produce quality at low minimum orders, allowing them to release products regularly, gather customer feedback and iterate quickly. They did not start with a unique fabric or a revolutionary design. They started with solid quality, consistent sizing, good branding and a community-first marketing approach.

The manufacturing side of that story is accessible to any brand starting today — arguably more so, because the global network of private label activewear manufacturers offering low MOQs has expanded dramatically since 2012. The community-building side requires time and consistency. But the product quality side is solvable from day one if you choose the right manufacturing partner.

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What to Look for When Evaluating a Custom Gym Wear Manufacturer

Finding a list of manufacturers is the easy part. Choosing the right one requires asking the right questions. Here is what we recommend evaluating:

In-House vs Outsourced Production

Some manufacturers quote your order and then outsource production to a third factory. This adds a layer between you and the person actually making your product, which means less quality control, slower communication and higher risk of inconsistency between orders. Always ask: do you cut, stitch and finish in-house, or do you subcontract any part of production?

Fabric Sourcing Transparency

A good manufacturer should be able to tell you exactly where their fabrics come from — country of origin, yarn composition and the mill name if possible. Fabric is where corners are most commonly cut. A manufacturer who buys from a consistent reputable mill will deliver more consistent results than one who sources from whoever has the lowest price that month.

Seam Construction for Activewear

For gym wear specifically, seam construction makes a visible quality difference. Flatlock seaming — where the seam is stitched flat against the fabric rather than raised — is the standard for performance activewear because it eliminates chafing and gives a cleaner aesthetic. Ask specifically whether your product will be made with flatlock or standard overlock seaming. Budget manufacturers often default to overlock because it is faster. It is a detail your customer will notice.

Sample Turnaround Time

Seven to ten working days is standard for a pre-production master sample. If a manufacturer is quoting you 4–6 weeks for a sample, they are likely backlogged and your bulk order will face similar delays. If they are promising 3 days, ask whether they are making a genuine sample to your spec or pulling a stock garment from their showroom.

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The Biggest Mistake Gym Wear Brands Make with Their First Order

Without question, it is ordering too many SKUs (products) at once. The temptation when you are starting a gym wear brand is to launch with a full collection — three colourways of leggings, a matching sports bra, a training top, a zip-through, a shorts style. It feels like a complete brand.

The reality is that splitting your first production budget across eight products means you will have shallow inventory in every style, almost no data on which colours and sizes actually sell in your market and a high risk of being left with stock in the styles and sizes that your customers did not want.

The brands that scale successfully almost always start with one hero product in one or two colourways — executed very well, stocked properly across all sizes, and promoted consistently until the sales data tells them what to add next. Your manufacturing partner can scale with you from there.

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Frequently Asked Questions — Custom Gym Wear Manufacturing

What is the minimum order quantity for custom gym wear?

At Gloves Storm, our minimum order for custom gym wear — including leggings, sports bras, shorts and training tops — starts from 30 pieces per style. That is enough to stock a range of sizes for a genuine product launch without committing to volume you cannot move. Some manufacturers in China require 300–500 pieces minimum, which is not viable for most brands starting out.

What fabrics do you use for custom gym leggings?

Our standard fabric for gym leggings is an 80/20 nylon-spandex blend at 220–240 GSM, which provides four-way stretch, excellent shape retention and a premium hand feel. We also offer polyester-spandex and cotton-spandex alternatives depending on the product brief and price point. All fabrics can be matched to your target spec on request.

Can you manufacture gym wear with my own branding?

Yes. We are a full private label manufacturer. Every garment is produced with your custom woven neck label, your hang tag, your branding on any print or embroidery elements, and your packaging. Your customer receives the product as a product of your brand — our name appears nowhere.

How do I prevent my leggings from being see-through?

Sheerness in leggings is almost always a fabric weight issue. A minimum of 200 GSM in nylon-spandex provides adequate opacity for most body types. We conduct a squat test on every sample before sign-off — if the fabric pulls sheer under stretch, we increase the weight before moving to bulk. This is standard in our QC process and not something you should have to ask for specifically.

Can you produce custom sports bras to match leggings?

Yes. Matching sets — a coordinated legging and sports bra in the same fabric, colourway and design — are one of our most popular product types for gym wear brands. We can produce co-ord sets from the same production run to ensure consistent colour matching between pieces.

Do you offer eco-friendly or sustainable gym wear manufacturing?

We offer recycled polyester (rPET) and REPREVE-certified fabric options for brands committed to more sustainable production. These carry a small premium over virgin fabric but are increasingly important for brands targeting the UK and European market where sustainability is a stronger purchase driver. Ask about this option when requesting your quote.

What is the lead time from order confirmation to delivery in the USA?

For first orders including sampling, plan for approximately 6–8 weeks from order confirmation to delivery at your US address. This breaks down as follows: pre-production sample (7–10 days), sample review and approval (your timeline), bulk production (25–30 days), and DDP air freight to USA (5–7 days). Repeat orders where samples are already approved typically move in 4–5 weeks.

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Gloves Storm manufactures custom gym wear and private label activewear for brands in the USA and UK from our direct factory in Sialkot, Pakistan. MOQ from 30 pcs per style. 7-day sampling. Full private label service. Request a free quote today or explore our gym and fitness wear range.