Recycled Polyester vs. Organic Cotton: An Honest Comparison to Help You Choose Your Sports Fabric

This article is for athletes and conscious consumers who want to understand the real differences between the two most commonly mentioned materials in eco-friendly sportswear. Spoiler: The choice depends on your intended use and your priorities.

Organic Cotton: What It Is (and What It Isn’t)

Organic cotton is grown without synthetic pesticides or GMOs, in accordance with certified environmental standards (GOTS, AB label). This is a significant improvement over conventional cotton, which accounts for approximately 25% of global insecticide use even though it covers only 3% of the world’s farmland (source: FAO).

But organic cotton is still cotton. And cotton has a fundamental property that makes it problematic for sports: it absorbs sweat without wicking it away.

A cotton T-shirt soaked with sweat stays wet. It becomes heavy, sticks to the skin, and can cause skin irritation and chills. For leisurely hikes or low-intensity activities, this is acceptable. For trail running, running, or any activity that causes heavy sweating, it’s a bad choice.

Benefits of organic cotton:

• Soft to the touch, very comfortable for everyday wear
• Biodegradable at the end of its life cycle
• Low microfiber shedding during washing
• Reliable certifications (GOTS, AB label)

Drawbacks for sports:

• Absorbs and retains moisture (feels like a wet T-shirt)
• Slow drying
• Heavy when wet
• Can cause skin irritation due to friction

Recycled polyester: What It Brings to Sports

Recycled polyester is made from recovered plastics (primarily PET bottles) that are processed into textile fibers. Its technical properties make it the go-to material for high-performance sportswear.

The key property: moisture wicking. Polyester does not absorb water—it draws it to the surface and transports it to the outside of the fabric, where it evaporates. The result: even after intense physical activity, the skin stays dry. This property, known as “wicking” in the industry, is impossible to achieve with cotton.

The environmental impact of manufacturing compared to virgin polyester:

• 64% reduction in energy consumption
• 94% reduction in water consumption
• 32% reduction in CO2 emissions (Source: Newlife study, certified recycled fibers)

Benefits of Recycled Polyester for Sports:

• Rapid moisture wicking
• Lightweight (can be as low as 120 g/m²)
• Dries very quickly
• Durability and resistance to repeated washing
• Reduced carbon footprint compared to virgin polyester

Drawbacks to be aware of:

• Releases plastic microfibers when washed
• Non-biodegradable
• Less soft to the touch than cotton (depending on the weight)

The Microfiber Issue: The Tough Part

Recycled polyester releases plastic microfibers during washing, which end up in wastewater and ultimately in the oceans. This is a real problem, documented by numerous scientific studies.

Some partial solutions exist:

• Washing at 30°C reduces fiber shedding
• Anti-microfiber laundry bags (Guppyfriend, Coraball) capture up to 86% of fibers
• Wash less often: After wearing it, airing out the garment may be enough

Research is progressing on surface treatments that would reduce this leaching without altering the fabric’s technical properties.

What about merino wool? The third forgotten contender

Merino wool is the big omission from this comparison. For sports in cold or wet conditions, it combines the qualities of natural and technical fabrics:

• Natural temperature regulation (warms when damp and stays comfortable)
• Antibacterial properties (prevents unpleasant odors)
• Biodegradable
• Very soft to the touch

Its drawbacks: higher price, less abrasion-resistant than polyester, and slower drying time than synthetic fabrics.

The Comparison Chart

Our recommendation

For trail running, road running, and high-intensity sports: recycled polyester blended with spandex for freedom of movement. This combination offers the best technical performance with the lowest environmental impact compared to virgin polyester.

For endurance sports in cold conditions (winter trail running, mountaineering, cross-country skiing): merino wool or a merino/synthetic blend for temperature regulation.

For low-impact activities (yoga, Pilates, walking, low-intensity indoor workouts): organic cotton may be suitable if you aren’t prone to skin irritation.

Frequently Asked Questions

Is organic cotton suitable for trail running or running? No, not for intense exercise. Cotton absorbs sweat without wicking it away, which makes the T-shirt feel heavy and wet. This can lead to skin irritation and chills after exercise. For trail running and road running, always opt for a technical synthetic fabric.

Can recycled polyester be recycled again at the end of its life? It’s technically possible, but rarely done on a large scale. Textile recycling remains an industrial challenge: blends of materials (polyester + spandex) complicate the process. Collection and recycling initiatives are emerging, but the industry is still in its infancy.

Is merino wool suitable for summer sports? Yes, fine merino wool (150 to 180 g/m²) is very well suited for summer sports. Its thermoregulatory properties work both ways: it keeps you warm in cool weather and regulates body heat in hot weather. For high-intensity summer trail running, recycled polyester is still lighter.

Le Colibri Frenchy T-shirts are made from certified recycled polyester, with spandex for comfort and freedom of movement. They are all assembled in France by local partner workshops.