Cycling gear is never going to be the most flattering to parade around in off the bike, but in the saddle we are fortunate to have some of the most advanced fabric technologies on the planet working to keep us warm,
dry and comfortable from top to toe, no matter what the weather has in store for us.
Now imagine adding into the mix having to deal with litres of sweat while also being lightweight and stretchy enough to be figure hugging and aerodynamic, as well as able to repel potentially harmful UV rays at the same time. That’s a big list of demands to place on our riding clobber and is a big part of the reason such a broad pricing spectrum exists for cycling kit. But what is the difference between a sub-£10 base layer from Lidl and one costing £90 from Assos? Can £300 ever be a justifiable price for a pair of shorts? Over to our panel of experts to lay the facts on the line and help you make up your mind.
Covering the bases
It’s generally accepted that layering is the key to success where clothing is concerned, and the layer in contact with our skin – the base layer – is certainly one where technical fabrics come to our aid. This is because it serves two key purposes, in insulation and wicking, which traditional fabrics simply can’t cope with.
Insulation is essentially about trapping air. It’s why, despite a counterintuitive appearance that seems as if it would offer little in the way of warmth, an open weave fabric or even a lightweight mesh base layer can actually serve you well in winter, as it creates thousands of tiny pockets of air that, when warmed by the body, create effective thermal insulation.
Read more - Snazzy Base layer guide
Wicking refers to transferring sweat from your body and on to the next layer, carried out by both capillary action and the permeability of the yarn. ‘We look for fabrics that draw moisture away from the surface of the skin and across the surface of the fabric as fast as possible,’ says Simon Huntsman, head of R&D at Rapha. ‘The principle is: the wider the surface area, the faster the evaporative cooling effect will be. If you slice through a Coolmax strand its cross section is like a child’s drawing of a flower. That increases its surface area and makes it more effective at moving moisture down the yarn.’
Coolmax is a hi-tech polyester fibre that only absorbs 0.4% of its weight in water, compared to 7% for cotton, hence you shouldn’t get that soaked effect associated with cotton garments, which quickly become sodden, damp and heavy. But it’s the ability to shift moisture more rapidly that manufacturers argue makes their technical polyesters truly stand out.
‘That’s not entirely a marketing-driven claim,’ says Dr Simon Hodder, tutor of ergonomics at Loughborough University and an expert in clothing and thermal environments. ‘But no matter what the fabric claims, once it’s saturated, it’s saturated, and that will seriously hinder its wicking properties.’ He also stresses the importance of fit, saying, ‘If a garment claims to be taking sweat away from the body, it needs to be in contact with the body.’
Merino wool is a popular choice for base layers. This natural fibre has a smaller diameter than many of its woolly contemporaries, meaning that it has a finer, softer feel against skin, but importantly it has also evolved to have anti-bacterial agents which prevent the build-up of odours – a rather convenient trait for a layer that’s often drenched in sweat. But where wool potentially falls down is a lack of stretch and, as Hodder has pointed out, a close fitting garment is crucial. ‘While wool has some natural “give”, we discovered that adding a fine polyamide [nylon] into the mix gives the wool additional stretch,’ says Tom Kay, founder of Cornish merino specialists Finisterre. ‘This really helps with stretch when tucked into a riding position, speeding up the wicking process without taking away from the natural qualities of the wool.’
Read more - best cold weather base layers
So is that the green light to choose a rib-squeezing base layer? No. Hodder adds a caveat, saying, ‘Manufacturers base their weaves on yarns per square centimetre, so once you stretch it apart you decrease that number substantially. So too snug a fit would effectively give more space for the sweat to leave, but at the same time you would lose some of its insulation properties.’
So it looks like there is substance behind paying more for technical base-layer fabrics, but if you want optimum comfort and performance then just remember to make sure your choice of garment fits properly before you buy.
Protection choices
Your upper body is susceptible to greater cooling than your lower body because, quite simply, it shouldn’t be putting much work in if you’re riding efficiently (just observe how still Fabian Cancellara’s torso stays as he rides). It should go without saying that good windproof and waterproof garments are worth their weight in gold – in fact in a lot of cases, gram for gram, they’re worth considerably more than gold. The best fabrics are not cheap. So where’s your cash actually going?
Well, you could look at it like this: on the one hand you want a fabric that’s lightweight, feels great next to your skin and breathes, so that it lets out any excess heat and moisture build-up creating your own dry and cozy sub-climate on the inside. Yet at the same time you also want it to put up an impermeable barrier to cold wind and/or rain from the outside. It’s a tough balancing act to achieve and this is where the big bucks are spent by technical fabric manufacturers such as Gore, Polartec and Schoeller to name a few to create versatile materials. However, there is no one-stop-shop for a garment that will cope with every condition Mother Nature can throw at us, although with the current rise of waterproof/water-resistant jerseys, spearheaded by Castelli’s Gabba jersey, we are arguably closer than ever to that goal.
Read more - Gore Element Windstopper review
Yet windproofing and waterproofing are two quite different challenges for a fabric. Water is trickier to halt than air. Defying logic, air (oxygen) molecules are actually larger (roughly 1.5 times) than water molecules. ‘To be windproof, you can have slightly larger pores in the material and a more open weave,’ says Hodder. ‘Windstopper layers are also most often slightly offset, so even if wind comes through it hits the layer underneath and diverts. It’s that hit-and-divert template throughout multiple layers that reduces the impact of the wind.’
Gore’s acclaimed Windstopper fabric, for example, is a membrane that sits between the lining fabric and outer fabric to deflect chilly breezes but crucially the size of the pores allows for adequate breathability.
Stopping water in its tracks is much harder as it has the ability to permeate through multiple layers, gradually soaking through by capillary action. Protection from water ingress, then, requires one of two possible solutions: either adding a coating to create an impermeable barrier (often onto the surface of the fabric) or making the pore size of a membrane so minute that water molecules will not fit through it.
Tetra-Poly-Wotsits
The latter is considerably harder and more expensive to achieve, but Gore-Tex is the most prolific example of such a membrane. Gore-Tex is an extremely thin layer of expanded polytetrafluoroethylene (ePTFE – a synthetic polymer), which on a microscopic level has a web-like structure that’s about 10 microns thick (one micron equals one-millionth of a metre). WL Gore, the maker of Gore-Tex, estimates that ePTFE contains 1.4 billion pores per square centimetre or about nine billion per square inch. And that is the key, according to Hodder: ‘It’s all down to permeability. The more you pay [for a material], the more it becomes about what’s in the material rather than what’s on the outside.’
Read more: Gamechanger - the first GoreTex jacket
Despite these microscopic holes, ePTFE is highly resistant to water. Why is down to what scientists call low surface energy. Water has a high surface energy, which means that water molecules are more strongly attracted to each other instead of different surfaces. Hence they always want to pull together into a shape that occupies the least amount of space on surfaces, such as spherical drops. When water contacts ePTFE, it quickly consolidates into rounded beads and slides off. But you will notice that manufacturers still prefer to use the term ‘highly water resistant’ rather than ‘waterproof’ because it’s actually still possible for water to penetrate ePTFE, if for example there is enough force behind the water jet hitting the surface or if the ePTFE’s low surface energy is affected by contaminants. This is also why the membrane layer is often sandwiched between other layers to protect its properties – sweat could contaminate it and compromise its performance, for example, were it not lined where it could come in contact with your skin.
Other fabrics are used to similar effect, such as eVent, which is employed by a host of brands including Craft and is similar to Gore-Tex but differs at the ePTFE level – instead of adding polyurethane, it utilises an alternative polymer known as polyacrylate.
These are at the cutting edge of keeping our bodies dry. At the other end of the spectrum, a cheap waterproof almost certainly has to be treated, which means applying secondary coatings and running the risk they might
wear off after a number of rides or wash cycles. Plus if a waterproof material relies on poor-quality treatments and/or membranes it’s highly likely to stop moisture escaping too, so you’ll potentially just end up soaked from the inside by the build up of sweat anyway. This is the constant battle jacket manufacturers face, and no matter what the manufacturers might proclaim, no bike jacket can be truly 100% waterproof.
While all that sounds fairly negative towards surface treatments, some do have a very welcome place in the cyclist’s wardrobe. Cue Coldblack, a textile finish developed by Swiss company Schoeller. The coating purportedly reflects both visible and invisible rays of sunlight, leading to up to a 5°C drop in surface temperature versus a non-treated black top – technology that those perfectionists over at Team Sky are no doubt very grateful for in warmer races given that its Rapha team kit is predominantly black. It’s a great example of how modern technology is able to facilitate garments that are specifically tailored to our needs as cyclists. Who wants to wear white kit? Right.
Of course, no article about cycling gear would be complete without a mention of good old Lycra. Where does this most iconic material of all fit in among this highly innovative new stuff?
‘Lycra certainly helps you create aerodynamic [close-fitting] garments,’ says Steve Smith, brand manager at Sportful. ‘However, many riders don’t enjoy the way Lycra makes them feel, as it has a tendency to remain damp or even wet with sweat, which can have an unwanted cooling effect, especially on descents. So we set about the task of maintaining aerodynamics but reducing the Lycra content and upping polyester content so garments dry quicker.’
That’s not as easy as it sounds, though, given the intricacies of the way cycling kit needs to move, especially shorts with regards to the pedalling action. It’s a conundrum that leading brands are continually wrestling with.
Ultimately, though, Lycra’s place is mainly on our lower limbs, because even when it’s lined with a fleece backing, its insulation properties are not that great. Thankfully, our legs should be generating plenty of heat when we’re pedalling, so that most of the time heat loss isn’t a huge problem in this area. Just don’t spend too long sitting still at the cafe.
There’s a bamboozling array of kit out there, so the best advice we can offer is to opt for reputable brands that you can be confident have done their homework. Better still, if the clothing brand supplies a pro team there’s an even greater chance its wares are descended from kit that’s been tried and tested in some of the harshest environments. This means that what it promises on the label might well be the case in the real world, and when it comes to your Sunday club runs it should have you well covered. Pun intended.