As a running and cycling journalist, I spend a lot of time in sportswear. Lycra is my leg coverage of choice, polyester or merino wool my base layer, and I reach for technical materials like Gore-Tex if the weather isn’t playing ball.
A near-daily workout schedule means my washing machine’s sportswear setting takes a hammering to avoid having a laundry basket overflowing with sweaty, salty, sour-scented clothes. But even then, tops can develop hard-to-shift smells in sweat-prone areas, synthetic materials can start to bobble and lose shape, and my sportswear occasionally gets a foamy detergent residue that hasn’t been properly rinsed out, particularly during wet or intensive training sessions.
To find out how to resolve my washing woes, I’ve consulted experts on more sustainable ways to care for your sportswear and how to dispose of kit when it’s ready to go to the big gym in the sky.
How to make your sportswear last longer
Sort it straight away
“Don’t leave your dirty exercise clothes in the corner of your room or wardrobe, where they can stay damp and develop mould. You may not notice it, especially with darker sportswear, as mould spores aren’t visible until they grow to about half a centimetre in size,” says David Lambert, managing director at the laundry service Laundry Republic.
“If you’re unable to wash your sportswear straight away, keep it aired out as much as possible on a hanger or airer so that it doesn’t start creating a smell or damp. The first chance you get, put it in the washing machine inside out, as most of the sweat sits on the inside of clothes. If you can, especially during the summer, hang it on a line to air-dry after washing. Don’t put it on your radiators – the direct heat can damage synthetic fibres in sportswear, causing them to change shape. It can also lead to mould growth due to extra humidity, which can cause respiratory issues.”
Choose the right detergent
“I once heard that some standard detergents only really mask smells and don’t actually tackle the source of what causes odour to build up – bacteria,” says Will Renwick, professional outdoor gear tester and author of Peak Bagging Wales. “With some laundry liquids and fabric conditioner, there’s also the risk of them degrading elastane or synthetic fibres and clogging wicking channels, meaning the fabric can hold moisture and smells instead of pulling sweat away from the skin. To counter this, there are specialist detergents designed specifically for cleaning waterproof or performance clothing, including those from Grangers, Storm and Nikwax – the latter tends to be my go-to and has great sustainability credentials too.”
Grangers Active Wash, 750ml
Nikwax BaseWash, 1l
Wash sportswear separately from day-to-day clothing
“You shouldn’t be using fabric softener on any of your sportswear as it will start to damage and prematurely wear your clothes by clogging the synthetic fibres with a waxy residue, which can build up over time,” says Lambert.
“Also the fibres that make up sportswear garments are woven to be stretchable, but if you overstretch them it’s an irreversible situation,” he adds. “When your machine is on its final spin cycle, the clothes get spread out into the drum to take out as much of the water as it can. If you’ve got heavier or stronger fabrics, such as other clothes or towels, in the drum at the same time, they can damage sportswear. You might not notice immediately, but after six months of washing sportswear with day-to-day clothes, you’ll probably find the fabric has become too stretchy, and you’ll have to replace it.”
Bag it up
“I often use the Guppyfriend washing bag,” says Renwick. “It reduces and captures some of the microplastic fibres shed during washing, which matters because synthetic clothing is one of the biggest sources of microfibre pollution in wastewater.”
Guppyfriend washing bag
Tackle stubborn smells
“Even after washing, a fusty smell can linger on sportswear and towels, especially if sports kit was left in a bag in the car, or a towel was dropped on the floor in the shower room,” says Nancy Birtwhistle, author of Clean Magic: Essential New Tricks for a Sparkling Green Home. “Washing alone or dousing with lots of false perfume may not remove the odour, but an environmentally friendly washing soda soak can.”
Washing soda crystals (sodium carbonate) are a naturally occurring chemical compound that dissolve in water, making them a green alternative to other, polluting cleaning products. “They help neutralise odours in fabrics, but avoid using them with wool and silk because it can weaken the natural fibres. For a large sink full, add five to six tablespoons of washing soda, pour over hot water to cover the sink base and stir using a wooden spoon until the soda has dissolved and the solution is cloudy. Then add enough cold water to produce a tepid, deep bath and soak the items overnight. The next day, squeeze out excess solution, then wash in the machine.”
For natural fibres such as merino wool, Birtwhistle recommends soaking in one part white vinegar and two parts tepid water instead. “This solution is kinder to wool and can dissolve some stains, neutralise odours and prevent colour runs.”
Washing soda crystals, 1kg
Miniml white vinegar, 5l
Choose sustainable sportswear
“Merino wool is a miracle material in my eyes – it has such a long list of performance benefits,” says Renwick. “One big advantage is the wool fibres are naturally odour resistant. I do a lot of long-distance hiking where I can’t carry many spare clothes and have few opportunities to wash my kit, so I really rely on merino. Generally, brands like Patagonia say it’s best to wash a merino base layer after three to five wears, though I’ve pushed mine much further than that in the past. Good brands that make merino sportswear include Smartwool, Icebreaker, Devold and Brynje.”
Women’s Smartwool hike crew socks
after newsletter promotion
Men’s Icebreaker base layer top
Reproof waterproof layers
The move away from Pfas – synthetic “forever chemicals” historically used in some waterproofing treatments – has environmental benefits, but Paul Smith, equipment officer at Mountain Rescue England and Wales, says Pfas-free waterproofs require more maintenance to keep out the water.
“I’ll usually wash my waterproof jacket with Nikwax Tech Wash after a month of heavy use,” says Renwick. “This safely cleans the fabrics without removing any of the existing water-repellent coating. When my rain gear stops beading water and starts saturating easily, it’s a sign the outer fabric’s water repellency has worn off. Once that happens, the fabric can’t shed moisture properly, so it holds it on the surface instead – this stops the membrane from breathing, traps the moisture vapour my body is generating, and I end up wet from the inside instead of outside. That’s my cue to reproof with Nikwax TX Direct, which restores a fresh water-repellent layer to the outer fabric.”
Smith recommends tumble drying reproofed clothing on a low, gentle heat because the warmth “reactivates” the durable water repellent (DWR) – a thin chemical coating on a garment’s outer layer that can be renewed by reproofing. “You can also use a hair dryer or put your jacket near a radiator – lay it over a towel or hang it close to protect it from direct heat. When I’ve done mine, I always test it in the bathroom by sticking it under running water to see if it’s beading again.” But it’s always wise to check the manufacturer’s guidance for your items before tumble drying, placing near a heat source or warming with a hair dryer.
Nikwax Tech Wash, 300ml
Nikwax TX Direct, 300ml
Repair tears and cuts
“As part of our Zero to Landfill initiative at Mountain Rescue, we’ve got together with Scottish Mountain Gear to repair any [of our] kit that is damaged during callouts,” says Smith. “I sent in one of my own jackets after all the badges had come off, and it came back like a brand new jacket.” Some outdoor brands, including Alpkit and Montane, have in-house repair services, while Patagonia’s website shows how to repair a garment yourself.
Find a new use for old news
“I try to avoid putting my walking boots or shoes in a washing machine. To me, there’s too much risk of damaging the shoes and the machine,” says Renwick. “Instead, I hand-clean my gear. I love the Nikwax boot cleaning kit, which comes with a scrubbing brush.
“With walking boots, the crucial thing is to ensure you don’t store them away with mud on them; mud can draw moisture from leather, causing it to dry out and crack easily, and it creates a fertile environment for the materials to degrade, affecting synthetic footwear too.
“Waterproof footwear also needs help with drying out to prevent odours. Newspaper is surprisingly effective when stuffed into a pair of boots for a night.”
Dry boots naturally somewhere warm, but away from strong heat sources, which can crack leather and weaken glue, with the insoles removed and laces loosened to keep airflow moving; avoid resting them directly on any heat source.
“If you find you’re still struggling to get rid of bad odours from boots or running shoes, I often find it helps to swap in some new insoles. Superfeet makes some useful replacement ones,” says Renwick.
Nikwax footwear care kit
Superfeet replacement soles
Donate or recycle
“If you’re getting rid of jackets, give them to charities – lots want to get people out into the countryside,” says Smith. Kitsquad takes preloved outdoor clothing and passes it on to people with low incomes, while Ellis Brigham’s 2nd Life initiative redirects unwanted outdoor gear to charities supporting homeless people across the UK. “Failing that, if a garment is beyond repair, companies like Scottish Mountain Gear will recycle it.”
Follow manufacturers’ guidelines
“Most technical and outdoor garments come with specific washing guidelines on the label or the brand’s website, covering things such as temperature, spin speed and whether tumble drying or ironing is safe,” says Renwick. “Performance fabrics can be damaged by the wrong treatment in ways that aren’t obvious until the garment stops performing, so it’s always worth checking the label or manufacturer guidance first rather than assuming standard laundry rules apply.
“My base layer clothing for hiking and camping will usually either be merino wool or a synthetic blend, and I generally try to ensure I wash them both at a low temperature – 30C is fine for me. This helps prevent shrinkage in wool clothing and reduces stress on technical synthetic fabrics, especially when they have a high elastane content. Mid and outer layers can all be different, so I’ll always consult the labels. If in doubt, though, I’ll stick to that 30C temperature – if you don’t know, go low and slow.”
For more fitness inspiration from the Filter:
Personal trainers on the best home gym kit
The best treadmills for your home – tested
The best fitness tech and gadgets, according to experts
The fitness gear that made you fitter
Charlie Allenby is a health and fitness journalist whose near-daily running and cycling training regime means his washing machine is spinning almost as much as he is