Fossil-free Activewear: How to go from oil-based to natural fiber

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Activewear is an indispensable part of even the most modest wardrobes. These items are worn both in and out of the gym. A pair of leggings or biker shorts are among the most-used items in our closet. Their stretchy, body-hugging characteristics plus dual functionality as both day wear and workout gear have us wearing them a lot. Moisture-wicking, quick-to-dry property is a bonus.

However, activewear can be a blind spot when trying to shop more sustainably. We tend to put a spotlight on the mega fast fashion brands like Zara, H&M, and SHEIN when we think of clothing bad for the environment, but forget that 90% of the leggings, sports bras in the market are made almost entirely out of petroleum. Polyester gives sporty garments its light and sweatproof characteristics, while spandex, elastane, and lycra, are all 3 different names of the same oil-derived fiber. We need to start looking more at natural fiber.

“What about leggings made from recycled plastic bottles? Aren’t they sustainable?”

-most people

Not exactly! In fact in a recent article of Business of Fashion they stated that it’s better for plastic bottles to be recycled as plastic bottles than into leggings. Why? Because as bottles they can be continously recycled –as leggings their next stop is a landfill.

So unfortunately, they remain more of a marketing tactic than an environmental solution. After all, there’s still plastic coated in every fiber strand of the fabric. That means once your favorite green-label yoga pants reaches the end of its usable life, it’s not going to be in the minute 1% of clothes that gets recycled. And NOT-SO-FUN fact: It takes 450 years for PET to fully decompose, not to mention the amount of microplastic being released into the ocean and intoxicating marine wildlife as well as posing carcinogenic threats to humans ourselves. What we could aim for instead, is low-to-none synthetics in our activewear – enter key word: biodegradability.

Brands like Reprise, whose leggings and bras are made from Tencel, provide one antidote. Tencel is a plant-based natural fiber that has a high water absorption rate (50% more than cotton!), which makes it ideal for activewear. However in order to ensure the performance of performance wear, textile designers still have to include a certain amount of spandex, around 5%. The journey to sustainability is always imperfect, but brands who invest in natural textiles make it easier to go from oil-based to plant-based activewear.

Here is our list of 6 activewear essentials to own, from eco-conscious companies like Reprise, Nagnata, Pangaia, MATE the label, and more

1. Leggings

Even if you never plan to spend a single minute in the gym, leggings are still a must-have. Need I say their practicality? Reprise offers perhaps the most inclusive sizing. While Nagnata brings unexpected cuts and patterns, Pangaia breathes new life into good ol leggings with a rainbow array of colors and more.

Reprise Aspen Leggings

Their best selling legging. Your skin will thank you as it can finally breathe in our insanely soft super-luxe plant-based fabric. These leggings are ultra stretchy and will keep you cool during any activity from yoga to working from home. Designed for comfort, they fit high-rise and are ankle length (and opaque of course).

Instead of plastic bottles, they’re dedicated to using a tree-based fabric that’s grown in a clean and regenerative way. Composition is 93% TENCEL/7% Spandex.

Pangaia Women’s Activewear Leggings

Get physical in Activewear made from plants.

These full-length leggings are made from natural fibers like seaweed, eucalyptus, biobased nylon and a responsible stretch fiber. They’re a seamless, supportive and compressive fit with a high-waisted ribbed waistband. The fabric is breathable, soft to the touch and has four-way stretch to keep its shape. It’s treated with BioWick®, a plant-based treatment that absorbs unwanted sweat and PPRMINT™ oil for its anti-odor properties.

pact Women’s Purefit Legging

This high rise fit has a three inch waistband for a comfortable contouring fit. The Purefit Leggings are made in Fair Trade Certified Factories with Organic Cotton utilizing 28 gallons water less than used in manufacturing conventional cotton. The fabric also includes elastane for stretch.

89% Organic Cotton, 11% Elastane

2. Sports Bras

Preferably in the same color as your leggings, so you can have a monochrome set that’s gonna be the base for so many outfits. Both MATE the label and pact, long time No Kill favorites, offer sports bras made from up to 95% organic cotton.

MATE the label Organic Stretch Sports Bra

Most activewear is notoriously bad for the environment because it’s made from synthetic materials that shed microplastics when washed. Our Organic Stretch is an entirely different story. While it’s impossible to get the necessary stretch for activewear from pure cotton, we got pretty damn close with a blend of 92% Organic Cotton and only 8% Spandex

PANGAIA Women’s Activewear Sports Bra 2.0

This scoop neck sports bra with straight straps utilizes biomaterials to create a supportive sports bra that will benefit you even with your sweatiest workout.  The Activewear Sports Bra 2.0 ismade from a decomposable nylon called Bio Based Polyamide and a small percentage of ROICA™ Elastane. It’s treated with BioWick®, a plant-based treatment that absorbs unwanted sweat and PPRMINT™ oil for its anti-odor properties.

Fabric: 95% Bio Based Polyamide and 5% ROICA™ Elastane

Skin Ora Bralette

This racerback bra with thin straps is perfect to wear to yoga class with leggings and is versatile enough to go from the studio to the sofa as loungewear. This lined sports bra utilizes Supima Cotton and a little Spandex for a comfortable and supportive fit.

Fabric: 90% Organic Pima Cotton, 10% Spandex

pact Women’s Modern Racerback Bra

pact’s racerback bra is available in 9 colors and is made of GOTS Certified Organic Cotton. In manufacturing, their organic cotton saves 11 gallons of water per bra compared to inorganic cotton. The bra features a supportive waistband and removable cups for secure coverage that will not get rumpled in a few washes.

Fabric: 95% Organic Cotton, 5% Elastine

3. Sets

There’s always room for monochrome sets, especially when it comes to simple cuts like those found in activewear. A snugly fitted set of a bra top and leggings is great for those gym to grocery picking cross sessions, but when it gets chilly we’ll need something to cover up. Enter: Sweats and joggers. So simple, so effective. Sustainability-wise, the non-stretchy nature of these comfy clothes means no need for synthetics, so 100% cotton is the way to go.

MATE the label Fleece Oversized Sweatshirt

Fleece Oversized Sweatshirt is made with a cozy blend of 50% Organic Cotton, 50% Cotton Fleece, and designed with an extra roomy fit for supreme comfort. Who knew you could find a sweatshirt of 100% natural fiber?

MATE the label Fleece Relaxed Pocket Sweatpant

This updated version of their bestselling sweatpant has the same relaxed fit and athleisure style as the original but now features pockets thanks to popular demand. A drawcord waistband and leg cuffs ensure the perfect fit. Still made in super soft blend of 50% Organic Cotton, 50% Cotton Fleece.

Pangaia 365 Sweatshirt SS22

This genderless medium-weight 365 Sweatshirt in Orchid Purple is made entirely of responsibly sourced, organic cotton. The inside has a comfortable loopback texture that has a finishing to make it feel extra soft.

100% Organic Cotton

Pangaia 365 Track Pants

The Orchid Purple 365 track pants are made from 100% Organic Cotton. Just like the 365 Sweatshirt it is made from a medium weight fabric, with a loop back texture inside and a finishing that provides extra softness. The pants have been treated with Pangaia’s PPRMINT™ oil to reduce odors.

100% Organic Cotton

4. sweatshirts

To stay comfortable on a jog or after a workout, you’re going to need more than one sweatshirt.

MATE the label Fleece Crop Sweatshirt

Equal parts cozy and cool with a cropped length for effortless style. This pullover sweatshirt has a relaxed fit and is made with natural fiber: the softest 50% Organic Cotton, 50% Cotton Fleece.

Pangaia 365 Signature Sweatshirt Core

Made in Portugal from a recycled-organic cotton blend, Pangaia’s sweat proves how dedicated the company is to sustainability. It’s dyed in blue using a recycled water system and even has responsibly sourced labels and threads inside, while the fleecy lining and heavyweight feel make it the ultimate winter must-have.

50% Recycled Cotton, 50% Organic Cotton

Pangaia 365 Signature Hoodie Core

This Signature Hoodie is made with a responsibly sourced, high quality, recycled and organic cotton mix. Like its sweatshirt counterpart, the color is created using a recycled water system. The fabric weight is a thicker, heavyweight recycled cotton that’s perfect for days you want a cozier feel. The material is brushed on the inside to feel luxuriously soft and fuzzy like plush.


If you’re one of those who wake up at 5am and run, or just want a jacket that’s gonna hold all car keys and phones and your hands when it gets cold, you’re gonna need one of these.

pact Gender Neutral Zip Hoodie

Lounge around or get things done in the organic cotton PACT® Gender Neutral Zip Hoodie with a relaxed fit, front zip, and drawstring hood.

100% Organic Cotton

adidas by Stella Mccartney

adidas by Stella McCartney Planet Sports collection progresses towards the future of sustainability. This unisex cropped hoodie is consciously crafted from 100% organic cotton, with a logo and ‘S’ planet graphic at the front.

Pangaia 365 Zipped Hoodie

The 365 zipped hoodie is made from 100% Organic Cotton. It’s a medium weight fabric, with a loop back texture inside and a finishing that provides extra softness.


Biker shorts challenge the cult item status of the leggings, and from what we see in recent years, it’s winning over its full coverage cousin. A pair of leggings that are a little bit out-there can be tricky to wear, but when it comes to biker shorts, going for colors and patterns is more welcomed.

Reprise Aspen Shorts

Instead of plastic bottles, Reprise is dedicated to using a tree-based fabric that’s grown in a clean and regenerative way.

93% TENCEL, 7% Spandex.

Nagnata Lucid Yoni Short

The Lucid Yoni Short is a limited-edition evolution of the classic mini Yoni. Designed in Nagnata’s signature organic cotton knit fabric, these mini shorts are the perfect style to go from studio to street.

75% GOTS Certified Organic Cotton 25% Nylon

MATE the label Organic Stretch Biker Short

While it’s impossible to get the necessary stretch for activewear from pure cotton, MATE the label got pretty damn close with a blend of 92% Organic Cotton and only 8% Spandex.

Back Beat Co. Organic Cotton Biker Shorts

Add a pop of color to your wardrobe with Back Beat Co.’s Biker Shorts in the color Jewel which is a cool fuchsia shade. For those who prefer a more neutral palette, they come in Rosin as well (left). These biker shorts have an elastic waistband and are almost entirely composed of GOTS certified organic cotton.

94% Organic Cotton, 6% Spandex

-Sammie Wilhoit

Note: While we pick all of these independently and are not paid, we may receive a small commission if you shop through our links


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