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Whether you’re skiing or walking the dog, these thermal leggings, vests and underwear will add extra warmth
Thermal gear isn’t just for the depths of winter. In a country where temperatures aren’t exactly predictable, the best thermal clothing can enable us to continue doing the activities we love the most when the weather takes a turn for the worse.
If you’re a winter sports fan, thermal gear will help you stay warm and dry, whatever the weather, enabling you to get the most out of your day on the slopes, by providing unbeatable temperature regulation, without cramping your style. However, these warming layers can be just as useful when you’re taking the dog for a walk on a chilly morning.
Thermals should wick away sweat while trapping heat close to the skin and preventing cold air from working its way in. Many thermal items do this with the help of polyester, which does a great job of trapping heat. It’s often associated with cheaper thermal items, though, as it can be less breathable than other fabrics. However, advances in manufacturing processes mean brands will often combine polyester with other materials, to ramp up the breathability.
Bamboo is also being used for thermal clothing by a growing number of brands. The hollow fibre is soft and versatile and does a great job of wicking away sweat. Then there’s merino wool – a premium material (with a premium cost) that ticks all the boxes, offering fantastic breathability and heat retention alongside a softness you’ll struggle to find with other materials. It’s also got antibacterial and antimicrobial properties, due to the lanolin and keratin wax produced by sheep.
Finally, a top tip: when choosing thermal wear, bear in mind that base layer items such as T-shirts and leggings will be a snug fit (this is one way in which they retain heat), so, don’t size up if you want your thermal gear to do what it’s meant to.
We love our thermals – although, we don’t just wear them on the slopes, as thermals are perfect for everything from winter walks to chilly bike rides. We take our thermals very seriously and when testing, we considered multiple aspects. Could we maintain full freedom of movement while wearing the garment in question? Did the material balance sweat-wicking with heat retention? Did certain areas chafe or rub? We considered all of these factors and more while testing a range of garments for this review.
Tamara Hinson is a keen skier and snowboarder (she used to be a snowboard instructor and was also a qualified ski and snowboard technician) and spends a large amount of the winter months in the French Alps, so she knows good kit from bad. As with all of our IndyBest reviews, each piece of thermal clothing has been trialled in a range of different conditions, and she’s only included items that past the rigorous testing process.
We absolutely love the two-tone design of this top but that’s not the only reason it’s a winner – it’s a garment that knocks it out of the park when it comes to technicality, too. The hi-tech two-layer construction; the presence of LIFA stay-warm technology (which basically pushes moisture away from the skin, upwards and outwards, so that it can evaporate); the generous use of merino; and the flatlock seams are just some of the features that combine to provide unbeatable warmth and comfort. The cut is second to none, and it was obviously a key focus for the designers. Take the hood – unlike many shallower ones, it will stay up in inclement weather, without detracting from the effortless style of the garment.
Mountain Warehouse’s own-brand products have always been known for their fab value, and we challenge you to find a merino wool top with a lower price tag than this one. We’ve stated that the material errs on the thin side but that’s not necessarily a criticism – this top does a great job of retaining heat and wicking away sweat, and it’s best seen as a technical top to be worn under jackets and jumpers on colder days, rather than one to be worn for your après-ski table-dancing session.
We love Decathlon – a store that does a great range of own-brand items alongside numerous wallet-friendly brands. One of our favourite products for this winter is this polyester and polyamide base layer top, designed for temperatures of between -10C to 7C and with sweat-wicking capabilities that kept us damp-free and warm on a blustery wet day. The material isn’t the softest we’ve come across, but it makes up for this with its technicality, paired with a flattering design suitable for both men and women.
We loved the cloud-like softness of this top, as well as the thickness of the material. It’s not the most technical of garments – it seems to rely more on the aforementioned thickness than space-age qualities to lock in heat, (we struggled to find in-depth information about the TrueTherm technology in question) but when a top locks in warmth this well – and for such a low price – we’re not going to quibble. We also loved the attention to detail, including the tag-less care information (it’s printed on the inside of the top) to minimise chafing, as well as the use of polyester made with recycled bottles.
This stylish hooded top did a brilliant job of wicking away sweat while retaining heat in all the right places. What’s more, its design ensures those pesky breezes are kept at bay, thanks to the high neck and balaclava-style hood. We reckon it’s particularly suitable for skiers and snowboarders – you might get a few odd looks when pounding the streets with the top’s balaclava hood raised. The material is also incredibly thin – we were sceptical as to whether it would provide enough heat retention but it did just that – and the use of Polygiene (an odour-busting treatment) kept nasty niffs at bay, even after a long run. Bonus points for the use of sustainably sourced bluesign fabric, too.
To be clear, these leggings aren’t labelled as thermal wear but they’re absolutely worthy of their inclusion in this round-up, simply because bamboo is a brilliant natural insulator, with thermal qualities to rival the most technical of garments. We won’t bombard you with jargon but, to put it simply, bamboo fibres are hollow, allowing them to trap warm air and keep it close to the body, while also wicking away sweat and allowing it to evaporate. For us, these leggings are best worn on colder days under ski pants or hiking trousers – we’re not ashamed to admit we’re sweaty Bettys when it comes to exercise, and we don’t think these will cut it worn alone for outdoor exercise sessions. Which is a shame, given the stylish go-faster stripes down the side. Don’t get us wrong, though – slip these on under ski pants, jeans or similar outerwear on colder days and you’re guaranteed to stay warm and dry.
Silky soft material and two gorgeous colourways (navy blue and olive green) make this base layer crew-neck top a must-have for stylish skiers and snowboarders heading to the slopes this winter. The brushed polyester did a great job of trapping heat, and the combination of a forgiving fit (which will be hugely appreciated by those prone to overdoing the après-ski) and lightweight material ramp up the versatility – slip it on under a ski jacket or wear it alone at your favourite slope-side bar.
Say hello to one of the most stylish thermal tops you’ll come across – a snowflake-adorned half-zip design made with top-quality merino wool, this top offers four-way stretch without chafing. We were particularly smitten with the high collar and long cuffs – snow, wind and rain didn’t have a chance against this particular garment, and we loved the extra-long zip, which made the top easy to slip on and off. Our only gripe is the tiny zip pull, which was tricky to grip (nigh on impossible with gloved hands).
After you’ve spent two hours shoehorning your little darlings into ski boots or hiking gear, the last thing they (or you) need is thermal gear that is scratchy or too tight, and that’s where Tog24’s thermal base layer set for kids comes in. This polyester top and leggings combo is ridiculously soft, while flatlock seams won’t irritate or chafe. The material’s breathability is a major bonus – kids aren’t able to regulate their temperatures as well as adults, but these items can be easily slipped on under jackets or ski trousers, without turning the wearer into a human kettle.
This highly technical base layer looks great and feels great. Clever use of different thicknesses of materials in different areas allowed for brilliant breathability in all the right places, while also aiding freedom of movement. Despite being a close-fitting top, it’s got the feel of a much looser garment, albeit one that traps warm air in the places most prone to chills, and lets hot air escape from the areas where we’re most likely to work up a sweat.
These are some of the softest thermal leggings we’ve come across – largely thanks to their fleece-like inner lining. This pair is another example of a thermal garment packed with tech. The stars of the show include the NILIT heat yarn technology, which provides unbeatable sweat-wicking, temperature regulation (fun fact: it’s made partly with coffee charcoal waste from coffee bean shells) and precision-engineered knitted panels. We loved the high waistband, as well as the material’s incredible lightness, which meant we were perfectly happy to wear these around the house, too.
Musto, a brand loved by seafarers, is known for producing highly technical garments that are built to last. This top is no exception, combining unbeatable temperature regulation with style, thanks to a flattering fit and a jaunty red trim down the side. But there’s plenty of substance here, too. A precision-engineered combination of polyester, polyamide and elastane provides brilliant sweat-wicking, and means this garment dries incredibly quickly.
Technical features worth highlighting include the twin needle stitch hem and cuffs (referring to a double row of stitches designed to provide extra stretch) and the raglan-style sleeves (made from continuous pieces of material that extend to the collar), which offer additional freedom of movement. We also loved the funnel neck, which helped us retain heat in cooler climes, while keeping us warm and dry.
Another wonderful example of a thermal garment we’re more than happy to wear loud and proud, UYN’s evolutyon pants rely heavily on natex, a hi-tech lightweight fabric that is similar to nylon but significantly tougher, and offers much quicker drying times (after all, nothing feels worse than slipping on damp, musty leggings that haven’t had time to dry properly).
An abundance of areas of breathability maximises comfort by aiding airflow. Meanwhile, thicker material around joints – areas especially prone to injury in cold weather – provides added protection, and Drylight technology (often referred to as absorptive knitting) provides fantastic sweat-wicking.
Thermal garments this light are a rarity, and we’re amazed at how well this close-fitting vest helps regulate temperature, keeping us warm without risking overheating. This is largely thanks to simple design features – such as larger sleeve holes – which are often overlooked, although, there’s plenty of tech, too. The star of the show is merino wool, which has natural odour control and temperature-regulating qualities, while the moisture-wicking two-layer construction will keep you dry and comfortable all day.
Weather, do your worst, because these trousers are designed to keep the wearer warm, no matter what the elements are doing. That said, the trousers are also incredibly comfortable, thanks to the 100 per cent merino wool construction. Four-way stretch and patches of cordura fabric (incredibly tough synthetic fibre-based fabric) on the knees and seat (aka the bum area) crank up the comfort, while providing extra protection in the areas that need it most. As an added bonus, the wool is ZQ-certified, meaning it’s sourced in ways that meet the highest animal-welfare and environmental standards.
We’re suckers for flattering leggings, and the contoured profile of these ones worked wonders. These are a rarity in the sense they’re super soft but highly technical, with precision-engineered areas of breathability that enable air to circulate – even during long workouts. This is down to the combination of hardworking but sustainable materials, including kapok – a natural vegetable-derived fibre with similar qualities to wool – and Biolight, another plant-based fibre, known for its supreme softness. We also appreciated the generous length, because nobody wants cold ankles.
Acai has crammed a supersized amount of tech into these thermal leggings, which can either be worn under items such as ski pants, or worn alone on cold days. They’re also designed with practicality in mind – we love the addition of a pocket, and the material is 100 per cent opaque (because, let’s face it, nothing’s worse than finding out your treasured leggings are semi-transparent, no matter how beautiful your booty).
Seam-free construction eliminates the risk of chafing – especially useful on garments made with thicker material, such as these – and we appreciated the addition of reflective tape on the leg, which will come in especially useful for winter walks on dark nights.
Yes, apparently, thermal knickers are now a thing. Although we were sceptical, we’re now total converts. Our initial concern related to breathability, because this isn’t an area where we’re overly keen to lock in heat. But the two-layer construction and brilliant temperature regulation (courtesy of a heavy reliance on polyamide) mean these are a joy to wear. However, although there’s plenty of freedom of movement, they are on the tight side – although, one advantage of this is the contouring effect. In short, our bum has never looked better. What more could you want?
We were sceptical about Arc’teryx’s rho women’s hoody, simply because the material is so thin, but this is a seriously hi-tech garment that uses precision-engineered production processes to create a versatile thermal top well worth the price tag. Bamboo Clothing’s balance seamless active leggings are essential for skiers and snowboarders – we loved this garment’s ability to retain heat and the softness massively ramped up the comfort. But, Helly Hansen’s women’s LIFA merino midweight hoodie has a hi-tech design that did everything we needed it to, blocking freezing winds and trapping heat without impeding our movement.
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