Winter Cycling Tips in 2020, Part 1: Heat and Moisture

January 1, 2020 on the Illinois Prairie Path, Batavia Spur

post by John Burnham

The following is two part re-hash of an article on winter cycling first posted in 2017.

Having experienced snow on Halloween followed by the second warmest Christmas Day in Chicago (since the beginning of record keeping in 1871) we have started settling into more winter-like weather; still, it's a little on the warm side for the month of January. At least today (as of this writing) there is a trace snow on the ground so it looks like winter.

It's overcast with the temperature hovering around the freezing point- not exactly pleasant weather for doing anything outside, let alone riding a bicycle. Or is it? There may be a few perfectly legitimate reasons for not riding, but cold and inclement weather should not deter you if you really want to get out on your bicycle (or snowshoes, or cross-country skis, etc.). Here is a basic guide, distilled from multiple sources and personal experience, for riding in not-so-perfect conditions.

TL;DR (Too Long; Didn't Read)

        1. DO NOT wear cotton next to your skin. Just avoid it altogether.
        2. Layer your clothing!
          ⇨ Synthetic (polyester) or Merino wool base layer next to the skin
          ⇨ Insulating middle layer
          ⇨ Windproof outer layer
          ⇨ Add or remove middle/outer layers as needed
        3. Avoid cotton
        4. Keeping your torso warmer will help keep your extremities warm.
        5. Cotton? Just Say NO.

Heat and Moisture Management!

"There's no such thing as bad weather, only unsuitable clothing." - Alfred Wainright, A Coast to Coast Walk

Probably the most important aspect of winter riding, or any activity outside, is clothing. You need to protect your body from the cold, but increased physical activity generates additional heat (and sweat!). Your main goal is to keep heat close to your body and moisture far from it. Your body sweats in order to keep you from overheating; when perspiration evaporates, skin surface temperature drops through evaporative cooling. However, keeping that moisture close to your skin when the temperature outside drops can cool you faster than your body can keep you warm, leading to discomfort (think of entering an air-conditioned building in a sweat-soaked shirt) and possibly hypothermia.

You can manage all this by strategically layering your clothing. Layers create pockets of empty space that act as thermal barriers (. You can adjust the level of insulation by adding or removing layers as your activity changes in intensity. Wear only one heavy layer and you risk overheating. Wear only one light layer and you risk freezing.

The materials used in each layer are important for managing heat and moisture generated by your activity. Remember, the goal is retain warmth and move moisture away.

BASE LAYER   The first layer, right next to your skin, should be a wicking material such as polyester ($), nylon ($), or merino wool ($$$). These materials wick moisture away from the skin and do not retain it, unlike cotton (here's why). Other synthetic materials such as rayon, viscose, tencel, lyocell, bamboo and silk are more like cotton; they can retain water and will lose most of their insulating properties when wet.

The most important base layer is your top- protect the core (more on that in Part 2)! A base bottom layer may be necessary, depending on the temperature and your tolerance for cold down there. My legs generally need less insulation than my upper body, so I save my merino wool bottoms for really cold conditions (below 20°F).

MIDDLE LAYER   The next layer is for insulating. This can be a sweater or jacket made of synthetic fleece or standard wool, both of which are very good at trapping air while retaining very little moisture. Middle layers can be shed or added, depending on the temperature and/or activity level (how you carry around layers you are not wearing is a topic for another time).

OUTER LAYER   The outer layer at its most basic is a shell for blocking wind and precipitation. Better shells will have "breathable" properties that allow water vapor to pass out while keeping rain from getting in (think: GORE-TEX® and similar materials). Some jackets include zippered vents under the arms and in the torso that can be opened as needed to further expel moisture and manage heat.

Windproof tights complete the ensemble, but if tights aren't your thing, wear some kind of windproof/water-resistant pant. Again, and I can't stress this enough, AVOID COTTON FABRIC. Shell pants over a wicking/insulating base layer are a good call when the temperatures get really low.

In Part 2, I will go over hands, feet, head, and bicycle.