More Than Just Workout Clothes

As a physiotherapist, my day revolves around movement. I spend hours observing how bodies align, how muscles fire, and how skin interacts with the gear we wear to perform.

But activewear no longer stays confined to the gym or yoga studio. Our workout or yogalates outfit often becomes our daily uniform — from the morning walk and coffee run to school pick-up, grocery shopping, and brunch with friends. It has quietly become a social norm.

We spend a lot of time talking about supportive shoes, posture, recovery, and mobility, yet we rarely discuss the chemical composition of the fabric sitting directly against our largest organ… our skin.

If you are living in your activewear from sunrise to sunset, it’s worth understanding what is actually woven into those fibres.

The Hidden Risks in Synthetic Activewear

Most “high-performance” activewear is made from synthetic petroleum-based fabrics such as polyester, nylon, and spandex. While these materials provide stretch and compression, they are often treated with a cocktail of chemicals designed to make them moisture-wicking, stain-resistant, wrinkle-free, or odour-proof.

PFAS, often referred to as “forever chemicals,” are commonly used to create water and sweat resistance. These chemicals have been linked to hormone disruption, immune system issues, fertility concerns, and certain cancers.

BPA and phthalates can also be found in some polyester blends and plastic-based fabrics. These are known endocrine disruptors that may mimic estrogen in the body and interfere with hormonal balance.

Another concern is antimony, a heavy metal commonly used during polyester manufacturing. Prolonged exposure may contribute to skin irritation and respiratory concerns.

Formaldehyde is also frequently used to prevent wrinkling and shrinkage in fabrics. Unfortunately, it is recognised as both a skin irritant and a potential carcinogen.

Why This Matters for Your Health

When we exercise, our body temperature rises, circulation increases, and our pores open.

Sweat can act as a solvent, potentially drawing chemicals out of the fabric and increasing skin absorption. Over time, this additional “toxic load” may contribute to skin irritation, contact dermatitis, hormonal imbalance, respiratory irritation, and increased sensitivity in those already prone to allergies or inflammation.

For women especially, daily exposure to endocrine-disrupting chemicals through clothing is becoming an increasingly important conversation in holistic health.

Physio Lisa’s Guide to “Healthier” Activewear

The good news is you do not need to sacrifice comfort or performance to make healthier choices.

Merino wool is considered nature’s performance fibre. It is naturally moisture-wicking, temperature regulating, breathable, and antimicrobial, meaning it resists odour without requiring chemical treatments. It is also biodegradable and free from synthetic plastic fibres.

Tencel, also known as lyocell, is made from sustainably sourced wood pulp and is incredibly soft, breathable, and gentle on sensitive skin. It naturally inhibits bacterial growth and offers an eco-conscious alternative to polyester.

Organic cotton is another excellent option. Unlike conventional cotton, which is heavily treated with pesticides and harsh chemicals, organic cotton is grown more naturally and is kinder to both the body and the environment. If you still want stretch and flexibility, look for blends using safer degradable stretch fibres such as Roica® V550.

Bamboo fabrics can also feel beautifully soft and breathable. However, quality matters. Choosing bamboo processed in a closed-loop system helps minimise toxic chemical exposure during manufacturing.

The “Golden Rule” Before You Buy

When shopping for activewear, take a moment to check for trusted certifications that test for harmful substances.

OEKO-TEX® Standard 100 ensures every component of the garment has been tested for harmful chemicals and deemed safe for human use.

GOTS, which stands for the Global Organic Textile Standard, is widely considered the gold standard for organic textiles, certifying both organic fibres and environmentally responsible production practices.

Your Skin Absorbs More Than You Think

Your skin is not just a protective barrier — it is also absorbent.

The next time you reach for those super-shiny plastic leggings, it may be worth asking whether they are supporting your wellbeing or silently contributing to your toxic load.

At The Self Project, wellbeing is about the small daily choices that shape long-term health — how we move, how we breathe, what we consume, and yes… even what we wear.

Move well.
Breathe well.
Wear well.

Namaste