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Now there's no excuse for skipping a run... Stainless Steel Sleeving
When it's chilly outside, keeping the motivation up to train can be difficult. So what's the solution?
Alongside a good pair of running gloves, a gilet or vest and even a running beanie, a base layer can help to keep you at an optimum temperature.
In a rush? No need to sweat. Here are the best base layers we've tested, at a glance. Keep scrolling for the full list.
A base layer is a thin layer of clothing that helps your body to regulate your temperature when you’re running. They're designed to fit like a second skin; in the winter, they’ll preserve your body heat by providing a layer of warmth, while absorbing and evaporating your sweat. In the summer, they can help to keep you cool and dry when it’s warm. Most will also have compression elements to their design.
You can get different types of base layers too, from vests and t-shirts designed for the summer months, through to long sleeved tops made from thicker fabrics. Base layers aren't just your top half either; you can also get shorts and leggings for the same purpose.
Fit: A base layer is designed to fit like a second skin, so it needs to be snug but not so restrictive that you can’t move your limbs freely while running.
Fabric: You want to opt for a fabric that’s stretchy, sweat-wicking, fast drying and – most importantly – warm. The most common materials to look for are merino wool and synthetic fabrics like polyester.
Features: Base layers sit right besides your skin, so the last thing you want are seams that rub and cause unnecessary chafing. Look for seamless or flat-lock seams to avoid friction.
Thickness: Whether or not you opt for a lightweight, medium-weight or heavyweight base layer really comes down to personal preference. The colder the conditions you'll be running in – especially if there's snow on the ground – the thicker you'll probably want to go. But don't underestimate the importance of layering either. You can always go with a slightly thinner base layer and add layers of clothing on top, removing them if you start to feel too hot.
To help you element-proof your next run, we’ve put the best base layers for men and women through their paces. The Runner’s World Lab asked a panel of runners to try each one on at least three outdoor runs, rating them on warmth and how dry they kept when working up a sweat.
They also scored each for fit, design and comfort, and put each top through the wash to note any changes in colour and fit. You’ll find their top recommendations below, stamped with the Runner’s World Expert Tested logo.
The remaining base layers have been chosen by the Runner’s World editors, so there’s something for every need and budget.
A winner among our testing panel, this one has the added benefit of hand-warming mitts, for those particularly crisp mornings. Our male runners appreciated its streamlined style too, rating the fit and cut of the top highly, while the chafe-free guarantee also checked out.
However, our female panel would have appreciated a little more freedom of movement; some found the fit a little tight, or that it rode up during a run. Pockets for your keys, however, went a long way.
While it's not a running base layer by name (they called it a cycling base layer), if you're worried about staying warm this winter and want an affordable layer to chuck on before you head out, this is a smart choice and does a great job.
Craft has been making base layers for all sorts of sports for many years now, including cross county skiing, and if there was ever a sport in which to perfect a cold-weather base layer, it's that!
For the money, this is a whole heap of base layer that performs really well in cold weather, wicking away sweat before it can make you feel cold and keeping it away. It's form fitting and the flat seams reduce the risk of chaffing.
If you’re looking for a well-fitting, simple, elegant and effective base layer for winter running, look no further than the Omni-Heat Baselayer Crew from Columbia. Inside, there's an Omni-Heat thermal reflective liner made up of metallic gold dots which reflect body heat, delivering instant warmth. It’s perfect for those days where there's a nip in the air, but you don't want to weigh yourself down with too many layers. At the same time, though, it fits nicely under a zip-up jacket or a gilet. 'I've found myself reaching for this time and time again,' said our tester. 'Form fitting yet comfortable, warm yet sweat-wicking. Size up if you don't want it quite so fitted, though.'
If you’re someone who likes to mix things up with other outdoor sweat sessions, like cycling, skiing or hiking, then get your debit card out. Versatility is the order of the day with this base from Icebreaker.
Our testers loved it for a variety of activities, keeping them comfy and at a good temperature throughout. If you like a snug fit, you might want to downsize as this came up large for some.
If budget is a consideration, then this is a sound choice. Made from 100% recycled polyester, it got a thumbs up for wearability and comfort. However, testers didn’t rate its sweat-wicking capabilities, so it might be best thrown on for recovery runs as opposed to your next fartlek sesh.
You’ll probably have seen a lot of runners with striped arms over the years and there’s a good reason why – Helly Hansen know what they’re doing when it comes to base layers.
Made with its own ‘Lifa’ technology to keep you warm as you move, this lightweight base layer is breathable, comfortable and insulating for chillier runs. Available in a number of different colourways in both men’s and women’s sizes.
The Brighton has been one of our favorite running base layers for years, and for good reason: Tracksmith’s mesh-woven merino wool provides extra breathable heat vents in key areas while still keeping the rest of your upper body cozy.
This base layer is a go-to undershirt on super cold days, and it’s also an adequately substantial single layer on crispy fall days. The construction has no seams, which means no chafing, and the fabric is so smooth and comfy that we tend to have a hard time taking ours off after a run. Out of context, it seems a bit pricey for a single long-sleeve shirt, but we can assure you that it’s worth every penny.
With a high zip-neck for extra warmth when you first head out the door, and extra ventilation when things heat up a bit, this base layer is a great choice for winter running.
Made from a super soft jersey material, the bamboo makes this layer extremely absorbent, keeping you dry as you run. There's also thumb holes for extra warmth on days when you forget your running gloves.
A ground-breaking construction process – spinning merino fibres along a high-performance filament – means the Nuyarn fabric used by outdoor innovators Artilect amplifies the merino wool’s natural properties to make it even lighter, more breathable and quicker to dry. We can testify that it performed superbly in a wide variety of conditions.
While we tend to prefer a light or mid-weight base layer for a good blood-pumping run, there’s no denying that some winter days are just dreadfully cold, regardless of how hard you work yourself. Thankfully, this zip-top from Patagonia can be your buddy through those bitter chills.
This top traps a lot of heat compared to our other picks, protecting up to your neck when it’s zipped — having a quarter zip is so critical when you’re looking at a heavyweight layer. On top of that, this shirt is still form-fitting enough to sit comfortably under your vest or jacket, but it also has enough shimmying room that you won’t feel like the tin man without oil when you’re donning layer three or four.
With smart details including thumb holes, high-vis panels and even a slit to check your watch for those all-important stats, this top from Nike is the crème de la crème of base layers. Scoring highly with our testers, they found the top to be comfortable, a good fit and a decent thickness for staying at an optimum temperature.
A great technical running top to wear as a base layer, or on its own when the weather is milder. It’s insulating without making you feel like you’re overheating in the final few miles, and the fabric is lightweight, with plenty of ventilation.
The latest version of Lululemon's high tech base layer, our Deputy Digital Editor was impressed by the changes – the fit is more comfortable, the thumbholes are improved and the top retains its shape wash after wash. Plus, it comes in a number of colours to suit every running wardrobe.
A mid-weight merino wool base layer for cold running, this is a great under-layer for your training. Compared to other synthetic running layers, the inner layer of this top is sweat wicking, whilst the outer layer is water repelling, allowing it to absorb a greater amount of moisture before it feels wet. The fit is close to the body, and the layer is available in a number of different colours for both men and women.
Buy now - women’s
A go-to among team RW when the mercury drops, Megmeister’s baselayers provide serious warmth, super-fast moisture-wicking and great ventilation.
The ergonomic design, with a four-way stretch fabric, allows impressive ease of movement, while the seam-free material means there’s nothing to rub against skin.
The merino and silk blend is beautifully soft on the skin, as well as being warm and fast-wicking. All seams are flat-locked to minimise chafing and the top offers a close fit that still moves really well with your body. Like all the natural-fabric tops here, it’s also anti-bacterial, which helps to keep the wretched post-run whiffs at bay –always a bonus.
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