Why do cyclists love Merino wool?

How a natural fibre used by humans for millennia remains ahead of the herd

When creating a fabric for all-out performance, there’s an accepted tick list of features that need to be included. It should be antimicrobial, to resist the associated stench of effort. It should be breathable, to allow moisture to escape. It should be insulating, to keep the elements from adversely affecting muscles. And it should also be soft, to prevent any performance-inhibiting irritation.

In one way or another, almost all textiles destined for sporting use must have these attributes reverse-engineered into their construction – but not Merino. This wonder wool, benefitting from generation after generation of evolution, possesses each naturally.

Read our guide to the best Merino cycling jerseys

The Origins of a Super Wool

While it may seem like Merino arrived on the scene around the same time as Rapha, the material is fairly long in the tooth. In fact, wool clothing of some form has existed since as early as 2000 BCE. Merino, one of the softest and finest wools, is thought to have originated in southern Spain around the 12th century when farmers introduced their flocks to stock from North Africa and the British Isles.

Merino sheep near Christchurch, New Zealand (Photo: Getty)

Robust, hardy, and willing to graze almost anywhere, the emerging breed became so prized for its luxuriously soft wool that Spain’s rulers were prepared to execute anyone caught exporting one.

Fast forward to the late 18th century, and the colonisation of Australia saw both people and sheep arrive from Portsmouth. Within 50 years the Peppin brothers, originally farmers from Somerset, had taken over a large chunk of New South Wales. Here they would develop the Australian strain of Merino that still bears their name. Known around the world for its particularly fine and high-quality yarn, today it’s more likely than not that the Merino in any given product will have come from this same region. 

A Cyclist in Sheep’s Clothing

Of course, wool of one form or another has long been utilised in all kinds of clothing. A resilient material in itself, it’s often been the preferred material for utilitarian garments, and in particular, military uniforms and workwear.

No surprise then that wool jerseys were de rigueur in cycling’s early days where they protecting riders from the notoriously harsh conditions of early Tour de France races. Also setting the sartorial tone for decades to come, these first jerseys came complete with button-down shirt collars, ribbed sleeves, and chest pockets.

ashmei Croix de fer Jersey

Merino cycling jerseys are a long-established favourite for spring and early summer riding

Heavyweight wool certainly had its drawbacks, but until the limited introduction of silk jerseys by Armando Castelli in the late 1940s, it remained the only viable option. Thick and scratchy to the touch, what wool lacked in comfort, it made up for in drying time when compared with cotton. In fact, wool endured as many riders’ fabric of choice until at least the 1960s.

In one famous clash, French rider Louison Bobet even refused the yellow jersey at the 1947 Tour on the grounds that it was ‘unnatural’ – being one of the first maillot jaunes to feature synthetic materials. His argument? Cyclists had always worn wool, and wool was exactly what a racing cyclist needed for their long days of sweating in the heat and dust. Artificial fabrics did not transmit sweat, so it was a matter of hygiene, Bobet claimed.

The Arrival of Merino

Regular wool has always been thought of as an excellent insulator, as one glance at the clothing adorning early 20th-century alpinists and airmen will confirm.

However, Merino wool’s superior moisture management, insulating properties, and capacity for thermoregulation somehow remained largely unrecognised until the 1990s.

At the same time. while regular sheep breeds produce fibres with a diameter of 30-40 microns (one micron being one-millionth of a metre), Merino sheep wool fibres are often 20 microns or smaller, with some ultrafine Merino breeds producing wool with diameters as low as 10 microns – or about seven times thinner than a human hair.

In Merino, there existed a wool that not only performed well but was something you’d choose to wear against your skin. Crucially, this made it an option for those that privileged comfort alongside survival.

Shop ashmei's Merino collection in the Rouleur Emporium

Off the hills and onto the bike 

Founded by New Zealand entrepreneur Jeremy Moon, Icebreaker was among the first companies to harness its natural performance properties. Moon happened upon Merino following a chance encounter with a local sheep farmer and instantly chose the material as the basis for his first product – the Merino base layer.

At that time Merino had fallen out of fashion to the extent that his early supplier struggled to sell their produce. Also promoted on the other side of the world by Colorado-based outdoor clothing firm Smartwool, between them, their popularisation of the material ensured Merino farmers would never again have such difficulty in finding a market.

A Utilitarian Luxury

In the following decades, Merino flourished in the outdoor industry. First relied upon by hikers and climbers, then runners, and finally cyclists, Merino wool now finds its way into everything from socks and caps to jerseys and jackets. A stalwart of sporting comfort and performance, thanks to its environmental credentials and unique qualities you’ll find Merino in some quantity within an ever-increasing range of cycling garments.

Whether blended with other fabrics or used alone, in many respects this luxuriously utilitarian solution has yet to be improved upon. Not surprising when you consider it’s been millennia in the making.

The Science Behind the Fibres

Moisture Management

It’s Merino’s moisture management capability that marks it out as an unrivalled performance textile. While most materials feel wet after absorbing roughly 7% of their weight in water, wool can take on around 35% of its own weight before feeling as damp. But Merino doesn’t just absorb moisture, its fine fibres draw it away from your skin and help it evaporate – cooling you when you’re hot, and keeping you drier (and warmer) when you’re not.

Naturally Fresh

For cycling and other high-intensity sports, the real magic lies in Merino’s natural resistance to odour. Like all wool, Merino contains lanolin. A wax that’s used in lubricants and coatings, it’s naturally secreted by the sheep’s hair follicles to provide a degree of waterproofing and shield against bacteria. And because Merino wool manages moisture so well, there’s no wet environment for smelly bacteria to grow, leaving its wearer feeling fresher for longer even after strenuous efforts.

Superior Insulator

Wool is also one of the world’s most effective insulation materials. Thanks to the composition of its protein molecules, known as keratin, its densely packed fibres effectively trap tiny chambers of dead air. These can then store body heat, which in turn serve to insulate the wearer and mitigate sudden changes in temperature.

Produced in association with ashmei

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