How to Create Patterns for Sportswear: A Comprehensive Guide

Creating patterns for your sportswear is a key part of the process that needs to be completed before you produce the 1^st prototype. These patterns will get updated after every fitting to make the required adjustments and eventually you will need to grade these patterns to cater for the different sizes you would like to produce.

At Blue Associates Sportswear, we always suggest the factory that will make the final bulk production makes all the patterns as this not only speeds up the process, but they understand the fabrics and how they affect the fit.

We often get approached by start-ups that have invested in patterns through a freelancer or consultancy, to only find these are not workable or totally inaccurate once we nominate the final fabrics.

Below is a guide to the process of how to create patterns for your sportswear.

Why Sportswear Pattern Design is Unique

Before we dive into the steps, it’s important to understand what makes sportswear pattern design different from other garment categories such as general fashion:

• Functional Fit: The garments must allow for a full range of motion.
• Fabric Behaviour: Sportswear often uses stretch fabrics like spandex or lycra, which behave very differently than woven or standard knit fabrics.
• Compression and Support: Patterns must account for areas needing support or reduced movement (e.g., sports bras or compression tights).
• Aerodynamic and Minimal Seams: Seam placement is crucial to reduce chafing and improve aerodynamics.
• Construction methods: Many sportswear garments are produced using special seams, sewing methods or bonding to create stronger or less pronounced seams. The patterns needs to accommodate the required construction method for each seam.

Now let’s look at how to create a sportswear pattern from start to finish.

Step 1: Define the Garment Type and Purpose

Start with a clear idea of what you’re designing:

• Is it for high-impact sports like running or boxing?
• Or low-impact activities like yoga or pilates?
• Is the garment meant to retain warmth, wick moisture, or compress muscles?

Answering these questions will shape your patterning process. Different garments (e.g., leggings, rash guards, sports bras) will demand different fits and technical considerations.

Pro Tip: Always keep the athlete’s needs front and centre—this will help drive material and structural choices in your pattern.

Pro Tip: We always suggest you source the production fabric at this stage so you understand the properties and bulk of the fabrics. Stretch, thickness and construction of the material will define the garment construction and dimensions of the final pattern.

Step 2: Choosing the Right Fabric

Sportswear patterns are highly dependent on the fabric you choose. Most designs use one or a combination of these:

• Synthetic blends
• Spandex (Lycra/Elastane)
• 2 Ply Construction
• 3Ply Construction
• Natural fibre blends

The amount of stretch and recovery in the fabric will determine your negative ease (more on this later). A fabric with 4-way stretch behaves very differently from one with only 2-way stretch, and this will affect how you draft your pattern.

Some fabrics don’t have stretch at all and your garment may use 2 or 3 different fabrics for different panels to aid performance and this will affect the patterns and fit.

Tip: Always make a swatch test—stretch the fabric along both axes and record the percentage stretch. This will help you determine how much smaller your pattern should be than actual body measurements.

Again, using the factory to cut your pattern will be the best option as they are used to working these details out and create patterns that take into account the differences in stretch

Step 3: Take Precise Body Measurements

Accurate body measurements are the base for any well-fitting sportswear pattern. Common measurements include:

• Bust, waist, and hip circumference
• Inseam and outseam (for bottoms)
• Arm length and circumference
• Shoulder width
• Torso length (important for leotards or one-pieces)

Use a measurement chart or create a custom one based on your target demographic. When working with stretch fabrics, measurements are typically taken snugly but not tightly.

If compression is required, then the pattern will need to be cut smaller than the body.

Step 4: Understand Ease in Sportswear

Ease is the amount of space between the body and the garment. Sportswear patterns use:

• Negative ease (pattern is smaller than body measurements). Compressive garments.
• Zero ease (pattern equals body measurements)
• Positive ease (pattern is larger—rare in sportswear unless for outerwear or lower performance garments like sweatshirts and hoodies)

Negative ease allows the fabric to stretch and conform to the body, creating a snug fit that supports performance. It’s important to understand the percentage of stretch the bulk fabrics allows and make sure the patterns doesn’t exceed this, but allows the fabrics to stratch enough to create a tight fit.

Example: If a pair of leggings has a hip measurement of 100 cm and the fabric has 20% stretch, the pattern might be drafted with a 15–20% reduction in hip width (i.e., 80–85 cm).

Pro Tip: Check that the fabric doesn’t become transparent when fully stretched as this could compromise the look of the garment when exercising, making the fabric see through!

Step 5: Drafting the Base Block Pattern

Start by creating a basic block that corresponds to your chosen sportswear item. For example:

• Leggings block
• T-shirt or tank top block
• Sports bra block
• Jumpsuit or unitard block

You can draft the block manually or using CAD tools like CLO 3D, Optitex, Gerber, or Adobe Illustrator with pattern plugins.

Key points for pattern drafting:

• Ensure tight-fitting silhouettes for base layers.
• Factor in grainline direction—typically aligned with the direction of maximum stretch. Think about the athlete and where they  need the stretch and in what direction.
• Account for pattern reduction based on fabric stretch.
• Include shaping where necessary (e.g., darts may be omitted for stretchy fabrics but shaping through seams or panels is common).

Step 6: Incorporate Technical Elements

At this stage, functional features are added to the pattern:

1. Seam Placement

Avoid high-friction areas (like inner thighs or underarms). Strategic seam placement can enhance mobility and reduce discomfort. You might want to look at how the seams are constructed to allow maximum stretch or a flat seam.

2. Gussets and Panels

• Gussets (diamond or triangle-shaped inserts) are used in crotches or underarms for better movement.
• Panels can shape the garment and also allow for colour-blocking or mesh inserts. Using different fabrics in panels can effect fit, function and performance and can be added to increase all 3 elements.

3. Waistbands and Elastic Channels

Leggings, shorts, and bras require strong waistbands that stay in place during activity. These can be:

• Folded over fabric with inserted elastic
• Separate waistband pieces with compression fabric
• Integrated support bands (as in yoga pants)

Pro Tip: Sourcing the elastic that will be used for bulk production would benefit the pattern maker so they know and understand the function and stretch properties of the elastic.

4.  Seams

The seams and how they are constructed not only affects the stretch but also the patterns as each seam will have different seam allowances.

Flatlock seams is a different method to flat bed or overlock and therefore the seam allowance may differ. Bonded seams are also a potential construction method and the pattern will need to be altered to accommodate this type of production method.

Understanding the best seam construction for each seam is key to making sure the athlete feels comfortable and the garment performs well.

Step 7: Add Seam Allowances and Notches

Once your base pattern is finalised, add:

• Seam allowances: Typically 5mm–1cm depending on stitching or bonding method.
• Hem allowances: 2–4cm, especially for leggings and sleeves.
• Notches and markers: Indicate key points like front/back, waist, side seams, and panel joins.

It’s crucial to be consistent here, as even small mismatches in stretch fabric patterns can throw off the fit.

Step 8: Digitise and Simulate

If you’re using digital tools, this is where you simulate the garment using 3D avatars:

• Tools like CLO 3D let you sew and visualise how the garment moves and fits.
• Adjust patterns in real-time for better fit.
• Saves time and fabric by reducing the number of physical samples needed.

Digital simulation is increasingly used in professional sportswear development, especially by performance brands.

Step 9: Prototypes

Cut your prototype from the final fabric—don’t substitute with muslin or other test fabrics unless they match stretch characteristics and thickness exactly.

Tips for sewing stretch fabrics:

• Use a stretch or ballpoint needle.
• Use a serger/overlock machine .
• Avoid over-handling the fabric to prevent distortion.
• Use stay tape or stabilisers for areas like shoulders or necklines to prevent sagging as required

Pro Tip: Make sure you relax the fabric before you cut the panels out. If you don’t relax the fabric first, then the panels will relax and the prototype won’t fit.

Once sewn, conduct a fit test with a live fitting model or fit dummy that matches your size chart. Have them perform relevant movements: squats, lunges, stretches, or arm raises.

At Blue Associates Sportswear, we have a fitting model visit the studio every 7-10 days to fit our prototypes. These models are perfect mediums and are used to fitting sportswear, so give us important feedback when they try on garments.

Step 10: Test, Fit, and Refine

This is the most important part of the pattern development process.

Key Fit Checks:

• Does the garment stay in place during movement?
• Are there tension lines or excessive looseness?
• Are seams laying flat and not causing discomfort?
• Does the fabric compress/support as intended?
• Is there any bunching around the crotch or underarm?
• Did the seam threads snap when the garment was put on?
• Are the panels in the right place to aid performance and fit?

Refinements might involve:

• Adjusting seam placement or length
• Reshaping armholes or crotch depth
• Modifying panel sizes
• Sizing up or down based on performance and feedback

Don’t be discouraged if your first prototype isn’t perfect—sportswear requires multiple samples and we generally allow 2 prototypes to be produced before we are generally happy to proceed with placing a bulk order..

Step 11: Grading the Pattern

Once the base size is perfected, you’ll need to grade the pattern into a full size range so that every size has their own pattern.

Sportswear grading can be very tricky due to stretch properties. Standard grading rules may not always apply, and proportional adjustments are required.

If you want to create a wide size range, then typical size grades don’t work. For instance, a size 6 female may be 5ft10” and a size 20 female might be 5ft2”. Increase in size doesn’t always mean the height increases.

Pro Tip: remember to scale elements like pockets, zips, flies etc so these look in proportion to the final garment.

Some tips:

• Grade more conservatively in areas with lots of stretch.
• Grade based on body measurements + fabric stretch, not just static numbers.
• Create multiple fit samples across your size range to validate.
• Measure the size set samples to make sure the factory have followed the specification. If you are creating a wide grade covering 7 or more sizes, you may want to fit the extreme sizes.
• Always create the initial block as a medium or the middle of the different sizes you want to produce.

Step 12: Finalise Tech Pack and Prepare for Production

After final pattern approval, prepare your tech pack, which MUST includes:

• Final graded patterns
• Sewing instructions
• Stitch types and thread specs
• Label and tag placement
• Flat sketches with construction details
• Bill of materials (BOM)

This document is critical if you’re handing off production to a manufacturer.

Pro Tip: If you engage a freelancer to create the tech packs, make sure they source and nominate the bulk fabrics, trims and components and create the size block and grade. Nearly every tech pack we receive at Blue Associates Sportswear from freelancers don’t include these key parts as the freelancer doesn’t manage production.

We generally have to redevelop freelancer tech packs and add these critical elements, adding time and money to the process.

Bonus Tips for Sportswear Designers

• Study Athlete Movement: Observe how bodies move during activity to anticipate stress points.
• Keep Up with Trends: Fashion meets function—style details like cut-outs, mesh panels, or colour-blocking are important.
• Sustainability: Look into recycled fabrics or ethical manufacturing to meet growing demand for eco-conscious activewear.
• Feedback Loop: Build relationships with athletes, dancers, or trainers who can provide ongoing feedback.

Creating sportswear patterns requires a blend of technical skill, anatomical understanding, and creative design. From the initial measurement to the final prototype, each step impacts how the garment performs in the real world. While the process may involve trial and error, a thoughtful approach ensures the final product supports the body, enhances performance, and looks great doing it.

Whether you’re launching a new activewear brand or refining your design skills, mastering sportswear pattern creation is an essential part of the journey.

If you are wanting to develop sportswear and need patterns creating, then please get in touch now.