Although a base layer isn’t quite as sexy as a bike, when it comes time for winter riding and running no equipment choice is more important than what you wear.

When it comes to cycling and running technology, few categories advance as quickly as apparel. We combed through the newest tech to find out what will keep you warm as temps chill.

All In One

Designing cold-weather apparel for endurance athletes isn’t an easy task, but some mountainsport gear companies are nailing it. Quick-dry fabrics that help wick away sweat, thermal insulation for warmth, stretch for movement, and protective outerlayers are all built into a single garment for optimal functionality in the most challenging conditions. Mammut has taken this theme to an entirely new level. Its European-made Aenergy Light ML jacket uses Pontetorto Tecnostretch—a breathable jersey fabric that offers a technical outer surface with UV protection, high elasticity, and high thermal insulation. Weighing in at 320 grams, the jacket also features thinner Pontetorto Dryfast on the back and under the arms to help wick sweat ($140; Rei.com).

Going Green

Green products are in, across all outdoor sports categories—that goes for cycling and running apparel as well. Thanks to technological advances, fabrics and materials can be made from recycled goods. “Green gear” has reached new levels of function and fashion. German mountain sports brand Vaude may be the coolest company you’ve never heard of, and it was recently named Eurobike’s “Green Winner” for the best environmentally friendly product. Check out Vaude’s Green Shape Core Collection (Vaude.com) for apparel that looks awesome while riding or running and uses 90 percent biobased, recycled, or natural materials.

Woke on Wool

Wool is an incredibly versatile fabric. It’s great for ugly Christmas sweaters; it’s great in socks for keeping your feet dry; and it can also be your best friend during the chillier months. While you may think of wool as heavy and not particularly great for endurance sports, Merino wool—from Merino sheep indigenous to northern Spain—is incredibly light and soft, is moisture-wicking, and keeps you warm. Today, Merino sheep are mainly found in New Zealand, and that’s why Auckland-based Icebreaker (Icebreaker.com) makes literally hundreds of different garments from this amazing fabric. From base layers to jackets to leggings, look at new wool to keep you warm, dry, and light this off-season.

It’s Electric

People from colder climates claim staying warm is all about layering—and that’s true, to an extent. When the mercury dips dangerously below zero, you should probably consider taking your training indoors. But if you’re willing to take on whatever elements Mother Nature throws at you, you might need a little battery-powered assistance. 8kflexwarm is the leader in battery-heated jackets and vests—they’re warm enough for sub-zero temps but light enough for a winter run. Available in men’s and women’s sizes, The Heated Gilet ($254; 8kflexwarm.com) uses a USB- rechargeable power pack to provide up to six hours of heat on a single charge. The power pack even has a second USB port, so you can charge your phone while you warm your core.

Little Things/Big Difference

Anyone who has ever done a long ride or run in freezing conditions knows that keeping your toes from feeling like they’re about to fall off can be the greatest challenge. Toe warmers and wool socks can only do so much when the mercury really dips, so Meister created tiny neoprene “booties”—little sleeves that can be worn under or over your socks for an added layer of protection. Best of all, they’re cheap ($9; Amazon.com), and they can be the difference between turning back and heading home, or hammering out the extra miles on frigid days.