Base layers are one of those items you've seen on cycling apparel sites, but probably never thought about buying since you weren’t sure exactly when or why to use one. Hopefully, this article will help you understand a little more about them, their purpose and when they're best utilized.
What is a Base Layer?
Theoretically, a base layer is an “undershirt.” It’s the first layer of clothing you wear against your skin and is the “base” of your cycling outfit.
Why is it not just called an “undershirt?” Because that just wouldn’t be cycling! It’s the same reason that your seat is a “saddle” and your shirt is a “jersey.”
What are Base Layers made of?
Good quality base layers will be constructed from high-tech synthetic fabrics designed to wick sweat away from your body. Pactimo base layers are not only designed to wick sweat, but are woven with carbon fabric, which cools the body while also reducing odor.
Base layers made of cotton or other non-wicking fabrics should be avoided at all costs. Cotton will hold moisture near the body, making you feel clammy and increasing the incidence of rashes. Cotton, as a layer closest to your body, will make you hotter in hot weather and colder in cold weather.
When should a Base Layer be worn?
We are all accustomed to layering for cold weather situations. It’s the most effective way to regulate body heat (or chill) in changing weather conditions. But, the truth of the matter is, layering in hot weather conditions is also a good practice, so long as the base layer has been designed to wick and cool. Therefore, a well-constructed cycling base layer can be worn on cold days, hot days, in summer or winter, when racing, training or trail riding.
Base Layers for Cold Weather
Cold weather is probably the most common reason why cyclists opt to include a base layer. It provides an extra layer of insulation and pulls sweat from your skin, which will keep you dryer and warmer. That extra layer will also help hold warmth near the body. Typically, winter or cold weather base layers will be engineered with man-made fabrics, such as the extremely stretchy and lightweight Dryarn®. Fabrics like Dryarn are known for their low coefficient of heat dissipation, which prevents any unwanted loss of body heat and at the same time enables the rapid dissipation of excess heat via perspiration evaporation. Keeping the skin dry in cold weather conditions is key to retaining warmth and preventing hypothermic conditions.
Base Layers for Wet Weather
Base layers can also be extremely effective in wet conditions, especially those constructed with natural fibers. For example, Merino wool, while known for its exceptionally soft characteristics, is also naturally breathable and extremely efficient at regulating body temperature due to its great warmth-to-weight ratio. A soft, wool base layer is ideally suited for pairing with cold and wet weather garments since it will retain body heat when wet.
Base Layers for Hot Weather
Base layers can also be worn on warm and even hot days. Again, the high-tech fabric pulls sweat away from your skin while simultaneously creating an evaporative layer below your jersey. This helps the wearer maintains an optimum body temperature while remaining dry at the same time.
Other Benefits of Base Layers
Base Layers as a Compression Layer
Besides keeping the body dry, and helping with temperature regulation, the tight fit of base layers creates compression which contributes to improved blood circulation. You may have seen professional cyclists before or after a race wearing compression socks or leggings. Many even wear compression socks when traveling. That’s because the effects of compression layers has been proven to aid blood flow, delay muscle fatigue and increase performance (so much so that the UCI has banned compression socks from being worn while racing). A base layer can provide similar benefits through its tight fit and compression-like characteristics.
Base layers and Road Rash
A base layer provides another layer of protection in the case of an accident or crash. Essentially, if you fall off your bike, your jersey will catch the asphalt, but your base layer will keep sliding within the jersey. It may not protect you from everything, like broken bones, but having an extra layer between your skin and the road isn’t necessarily a bad thing!
Caring for Base Layers
Base layers, like all cycling apparel, should be washed after each use. Hand-washing with gentle detergents is the best way to care for them, but the delicate cycle in the washing machine is okay, so long as you hang dry. Putting cycling apparel in the dryer is never recommended. Drying technical fabrics used in base layers, jerseys and shorts will break down the protective coatings and integrity of the materials. Similarly, fabric softeners should never be used as they will only “gunk up the works,” so to speak, and will reduce the wicking abilities of the garments. Read Stop Washing at High Temperatures for more information about caring for your cycling clothing.
About the Author
Tony Kelsey has over 20 years marketing experience, previously serving as global vice president of creative for an international, $1B IT solutions consultancy. Although a self-proclaimed “mediocre” racer in high school, his intense passion for cycling and bicycles in general has never waned. Today he is VP of marketing at Pactimo and frequently writes about cycling as a sport and hobby. @tonykelsey