AMC Outdoors, December 2000

By Michael Lanza

As a kid, I tuned in regularly to the TV program Superman. I followed the caped hero's crusades for truth and justice with rapt attention, wondering: How does he battle bad guys, leap tall buildings in a single bound, and fly at supersonic speeds high in the stratosphere — in long underwear, without getting hypothermic or showing a spot of perspiration? Whatever his duds were made of, they weren't selling it in the kids' department at Sears.

The good news today is that the makers of outdoor clothing have discovered the magic fabric of Superman's long undies.

Whether you're flying through the stratosphere or wandering through the mountains on a cold, dry winter day, the various incarnations of fleeces and wicking base-layer fabrics will keep you warm and dry and prevent overheating. Versions of this stuff have been around a long time, but the competitive technical-garment industry is producing fabrics far superior to those of even a few years ago. Contemporary garments are more lightweight and compact without sacrificing warmth. They also breathe well, move with your body, and can be worn in a greater range of conditions. The following is a rundown of some of the newest things to wear in the cold. Many come in men's and women's sizes; weights given are for a men's medium unless otherwise indicated. (See also tips on layering.)

On the Bottom
Today's base-layer fabrics are more comfortable and versatile and better at keeping you dry. A recent lightweight innovation, Regulator — first introduced by Patagonia — has a gridlike pattern of fleece "pillars" on the inside to speed the transfer of perspiration from the skin to the air. It comes in three thicknesses, R1 being the base layer, used in Patagonia's R1 zip-T ($82.50, 11.5 oz.) and LoweAlpine's R1 Lattice Zip Neck ($69, 10 oz.).

L.L. Bean uses Power Dry Pique fabric from Malden Mills, which wicks like underwear but has the texture of cotton, in a short-sleeve T-shirt ($29, 8 oz.) and long-sleeve zip-T ($39, 9 oz.). EMS employs Malden's regular, stretchy Power Dry in its Midweight Bergelene zip-T ($29, 8 oz.), a long-sleeved zippered pullover which features thumb holes in the cuffs so you can use the sleeves as hand-warmers.

Another Malden product, Polartec Power Stretch, is a stretchy underwear that feels soft, dries fast, and comes in a range of weights or thicknesses indicated by a number (like Polartec fleece). It's used in the long-sleeve REI Yurt T-shirt ($45, 11 oz.), LoweAlpine Polartec Power Stretch Top ($89, 10.5 oz.) and Tight ($59, 8 oz.), and Outdoor Research Vector Vest ($60, 6 oz.) and Secant zip-T ($70, 8.5 oz.).

Devotees of good ole polypropylene might be interested in Helly Hansen LIFA, a polypro remake that boasts the feel and durability of polyester, yet stays drier and doesn't get smelly. It comes in three weights: Super Lightweight Crew ($25, 3 oz.), Sport Midweight ($28.50, 5.4 oz.), and Arctic Crew ($31, 6 oz.). How many times have you been out in moderate temperatures and a sporadic cold wind and wished for one base layer that provided enough warmth and actually blocked wind? Some companies are responding to that wish and at the same time redefining the phrase "base layer" with fabrics that function as both base layer and shell.

Among the first was the Marmot DriClime windshirt ($115, 10 oz.), a close-fitting jacket with a very lightweight nylon microfiber shell lined with Marmot's DriClime fabric, a fast-drying polyester. Following in Marmot's footsteps are the Moonstone Profusion zip-T ($99, 11 oz.) pullover and the EMS Windshear jacket-style windshirt ($69, 10.7 oz.). Mountain Hardwear recently introduced its Transition fabric, which sports a stretchy, breathable layer of W. L. Gore WindStopper. It comes in long-sleeve zip-Ts ($140 men's, $135 women's, 12 oz.), pants ($125, 10.5 oz. men's; $120, 10 oz. women's), and a unisex zip T-shirt ($99, 9 oz.).

The Insulation
Today's middle-layer fleece is much less bulky than its ancestors and increasingly features fabrics that stretch and contract with your body motion, meaning greater freedom of movement without your clothing bunching or riding up. The non-windproof fleeces breathe much better than windproof fleeces or waterproof-breathable jackets, making for a good insulating middle layer or an outer layer when wind isn't a concern. They also dry quickly, and some are even soft enough to wear against your skin.

For a soft, stretchy, light fleece, check out Columbia's Omni-Therm Pullover ($71, 14 oz.) or the REI Teton Pullover ($65, 10 oz.). L.L. Bean's Polartec Super 100 compressible jacket ($79, 13 oz.), with Power Stretch side panels, offers the warmth of Polartec 200 but is 25 percent more compressible.

The midweight Regulator fabric, R2, comes in Patagonia's R2 Jacket ($120, 14 oz.) and Levitator Pullover ($108, 13 oz.), which have stretch panels in the forearms/cuffs, sides, and shoulder blades. The company's R3 Radiant Jacket ($138, 18 oz.) is the fat fleece for the coldest conditions and has stretch fleece in the sides. The LoweAlpine Core Jacket ($129, 22 oz.) and Vest ($99, 13 oz.) combine Polartec Thermal Pro fleece and R2 with Malden's Power Stretch panels in the sides, sleeves, and shoulders.

Against the Wind
The strength of windproof fleece is its versatility as both an insulating middle layer and as a shell in cold wind that breathes better than a waterproof-breathable parka. The question is: How much breathability do you want? Anytime you make something windproof, you make it warmer and less breathable. Your decision depends on your needs for warmth and ventilation. The garments listed below vary in where they have windproof fabric (it's generally more useful in front) and where they have a more breathable, often stretchy fabric.

They also differ in how windproof they are — and thus, how breathable. For instance, WindStopper fabric, from W. L. Gore & Associates, and Malden's Polartec Windbloc are absolutely windproof, while Polartec Windbloc ACT blocks 98 percent of wind, making it more breathable than the other two.

A couple of companies are combining windproof fleece with Schoeller "stretch-woven," an abrasion-resistant, very stretchy, breathable, wind- and water-resistant fabric that's attracted a lot of attention in the industry. The Arc'teryx Sigma AR Jacket ($250, 22 oz.) and Vest ($160, 12.7 oz.) wed WindStopper with stretch-woven reinforcing panels in the shoulders and sleeves. L.L. Bean's Mountain Guide Fleece jacket ($139, 16 oz.) features lightweight windproof fleece in the body and stretch-woven in the sides, arms, back, and shoulders, and has pit zips.

Numerous other jackets and vests employ some combination of a windproof fleece in front and a stretchy, lightweight fleece in rear panels, differing in design, warmth, and breathability. They include the Helly Hansen Hybrid Jacket ($139, 24 oz.); LoweAlpine Ascent Jacket ($129, 21 oz.) and Vest ($99, 10 oz.); Marmot Ultimate Men's WindStopper Jacket ($225, 1 lb. 5 oz.); Mountain Hardwear WindStopper Flex jacket ($195, 20 oz.) and Vest ($135, 13 oz.); Outdoor Research Icarus Vest ($100, 10.5 oz.) and Ceres Tech Jacket ($170, 20 oz.); REI Hut Hopper Windhibitor Jacket ($155, 16 oz.); The North Face Sentinel Jacket ($235, 19 oz.), Men's Notus Jacket ($140, 15 oz.) and Men's Zephyrus Vest ($110, 9 oz.); and Wild Roses Gokyo Rose Vest ($100, 8.4 oz.).

This stuff might make you feel like Superman, so I should offer this disclaimer: Leaping tall buildings in a single bound is dangerous, and anyone attempting such a feat does so at his or her own risk.

—Michael Lanza is author of The Ultimate Guide to Backcountry Travel, from AMC Books