How to wash gym clothes so they keep their function and shape

Gym clothes made of technical fibres are best washed inside out, at a low temperature, on a gentle cycle and without fabric conditioner (fabric softener), then air-dried or tumble-dried on a low setting. That way, moisture-wicking and stretch are preserved. The care label is always what counts, but most sportswear brands recommend exactly these basic rules.

Why no fabric conditioner on sportswear?

Because it blocks the function. Stiftung Warentest (Germany's consumer testing foundation, in German) explains that after washing, fabric conditioner builds up on the fibres and makes the fabric water-repellent. The fabric then no longer absorbs sweat and no longer moves it outwards. According to Stiftung Warentest, it washes out again after a few washes without conditioner.

In its care guide, Nike gives a second reason: fabric conditioner residue acts like glue for odour-causing bacteria and makes cleaning harder. It is also better to leave out tumble dryer sheets with sportswear.

What temperature should I wash technical clothing at?

As cool as the label allows and the dirt permits. Nike recommends cold water and a gentle cycle for workout clothes. Under Armour prints "machine wash cold with like colours" on many products. Jako states 40 °C for its Jako Uni T-shirt. The number in the washtub symbol on the label is the upper limit, not the recommendation.

The Under Armour B Logo Wordmark T-shirt, made of 60 % cotton and 40 % polyester, and the Under Armour HeatGear Authentics leggings both carry the same instructions: wash cold with like colours, use only non-chlorine bleach if needed, tumble dry on low only, do not iron, no fabric conditioner.

What do the symbols on the care label mean?

Care symbols are standardised internationally; in Germany they follow the GINETEX system. One overview is the care symbol guide by C&A (in German):

• Washtub with a number: the highest permitted washing temperature in °C
• one bar underneath: wash gently (gentle cycle), meaning a smaller load in the drum and a lower spin speed
• two bars underneath: wash very gently (very gentle cycle), for example on a wool or delicates programme
• hand in the washtub: hand wash
• circle in a square: tumble dryer; the more dots, the warmer it may be dried; crossed out means do not tumble dry
• iron: the more dots, the hotter; synthetics usually only tolerate low settings or no ironing at all

How should I dry sportswear?

Ideally in the air. Nike advises drying workout clothes either on the lowest tumble dryer setting or entirely in the air, because heat can damage synthetic fabrics and elastane (spandex). Technical T-shirts dry quickly on a hanger anyway. Leggings and sports bras are better laid flat or draped over a line rather than hung by the straps. Direct heat from a radiator is just as bad for elastane as a hot tumble dryer.

How do I get sweat smell out of technical T-shirts?

According to Nike, it is not sweat itself that smells but the bacteria that break it down, and they sit mainly on the inside. That gives three rules:

• Wash clothes inside out, so the inside gets the most water and detergent.
• Do not leave wet things in your gym bag; hang them up as soon as you get home. Otherwise, Nike warns, mould and odour can develop.
• Do not use fabric conditioner, because its residue holds on to bacteria.

If you can only unpack wet clothes in the evening, use a bag with a separate compartment. The Jako Iconic sports bag has a deep zipped wet compartment on the side; the Erima Intro sports bag with bottom compartment has a separate bottom compartment for shoes or wet clothes. More on this in the gym bag guide.

How do I wash sports bras and leggings?

These pieces contain a lot of elastane and are therefore especially sensitive to heat. Close hooks and eyes so they do not catch on other items, and ideally wash sports bras in a laundry bag. Turn leggings inside out. Take out removable pads before washing and let them dry separately so they do not shift. Tips on support and fit are in sports bras: size and support.

What does a technical T-shirt cost per workout?

That is easy to estimate: purchase price divided by the number of workouts in which you wear the item. An example with round numbers: a T-shirt for €30 that you wear once a week over two years comes to about 100 uses, so about 30 cents per workout. A pair of leggings for €50 with the same use comes to about 50 cents.

How long an item actually lasts depends on the material, use and care; there is no fixed number. But care is the part you control yourself: if you wash hot, use fabric conditioner and tumble-dry on a high setting, you cut the number of uses and so raise the cost per workout. A stretched-out waistband or a T-shirt that no longer wicks sweat is the moment the calculation ends.

Checklist: washing gym clothes

• read the label: temperature, bars, tumble dryer symbol
• turn inside out, close zips and Velcro
• wash with like colours
• low temperature, gentle cycle
• no fabric conditioner, no tumble dryer sheets
• air-dry, or tumble-dry on low if allowed
• hang wet things up straight after training

Which fabrics are in gym clothes and why they behave so differently is explained in gym clothes: which fabrics. For cycling clothing with a chamois pad, there are separate tips in washing and caring for cycling clothing.