Activewear Fabric by the Yard | Leggings & Gym Fabric | Stretchhouse

The activewear market has changed what people expect from workout clothing — and those expectations have raised the bar for the fabrics that make it. Leggings that bag out at the knees, sports bras that lose shape after ten washes, shorts that become transparent when stretched — these failures all start with the wrong fabric choice. At Stretchhouse, we supply the fabrics that professional activewear brands, independent designers, and experienced home sewists use to make workout clothing that actually works.

What Makes a Good Activewear Fabric?

4-way stretch with strong recovery — Leggings must stretch during every movement and spring back immediately. Recovery is the critical factor that separates quality from cheap. Opacity under stretch — Hold the fabric up to light and stretch it. Quality activewear fabric (200+ GSM) remains fully opaque at maximum stretch — the squat test is real. Moisture management — Synthetic fabrics naturally wick moisture, but smooth-face fabrics like Milliskin and Supplex are most efficient. Durability — Quality fabrics maintain performance through years of machine washing.

Best Activewear Fabrics at Stretchhouse

Milliskin Matte: The Leggings Standard

Milliskin Matte (80% Nylon / 20% Spandex, 210 GSM, 60″ wide) is the most popular fabric for quality leggings. At 210 GSM, it’s dense enough to remain fully opaque even under stretch and strong light — the fabric that actually passes the squat test. The smooth, matte surface gives a sophisticated, versatile aesthetic. Available in 50+ solid colors. Machine washable, maintains shape through repeated washing, and comfortable against skin during extended activity.

Supplex Spandex: Soft-Touch Athletic Performance

Supplex Spandex is the choice when softness matters as much as performance. A specialty nylon processing that creates a fabric with a cotton-like feel, moisture-wicking performance, and UPF 50+ UV protection in a 4-way stretch construction. Softer against skin than standard Milliskin — closer to a luxury cotton feel than synthetic. Best for yoga pants and studio wear, athleisure pieces, outdoor fitness, and any activewear worn by people with skin sensitivity to standard synthetics.

Athletic Mesh for Ventilation Panels

Athletic mesh is used for ventilation panel inserts in activewear construction — the mesh panels along the sides of a legging, the back of a sports bra, or the underarm of a fitted top aren’t just aesthetic: they provide targeted ventilation that makes high-intensity activewear significantly more comfortable. Pair with Milliskin Matte or Supplex for a complete activewear garment with solid coverage and breathable mesh sections.

Fabric Weight Guide for Activewear

How Much Fabric for Leggings and Activewear?

Frequently Asked Questions

What is the best fabric for making leggings?

Milliskin Matte (80% Nylon / 20% Spandex, 210 GSM) is the most commonly used fabric for quality leggings — it’s opaque, smooth, color-retentive, and holds its shape through repeated wearing and washing. Supplex Spandex is an excellent alternative for a softer, more cotton-like feel.

How do I know if leggings fabric will be see-through?

The opacity test: hold the fabric up to a bright light source and stretch it to the degree it would be stretched on a body in motion. If you can see your hand clearly through the fabric, it will be see-through when worn. Quality leggings fabric (200+ GSM nylon spandex) should remain opaque under this test.

What thread should I use to sew activewear?

Use 100% polyester thread with a stretch stitch or narrow zigzag on your sewing machine. A serger with a 4-thread overlock stitch is ideal for activewear seams — it creates flexible, durable seams that move with the fabric. Avoid cotton thread, which won’t stretch and will break during wear.

Further reading: What Is Milliskin Fabric? | History of Spandex | Sewing with Stretch Fabric