Polypropylene versions can be purchased inexpensively. Many runners used to wear polypropylene caps inside wool caps in extremely wintry weather, so now you can buy wool-knit hats with polypro liners. Gloves or mittens help also. Many runners prefer mittens in extreme cold on the theory that keeping all the fingers together preserves warmth. Runners can buy gloves or mitten of polypropylene, Thermax, or Capilene, or even Gore-tex mittens lined with wicking fabric to keep sweaty palms dry.
Socks are another factor for runners to consider in winter.
The cotton and wool sport socks of old absorbed moisture on the run and were subject to shrinkage in the wash. Acrylic is the most popular synthetic fiber used to make socks today. It takes well to laundering, holds its shape, can be knit to provide extra cushioning and has wicking properties not found in natural fibers. Some of the space-age fibers used to make running clothes also now are used to make running socks. Polypropylene and Thermax both make for lightweight socks that wick moisture efficiently.