Base layers are not only for winter wear under ski/snow gear (although this is a great use for them). The great thing about base layers is that they can be used for recreational activities all year long. Although synthetic base layers dry fast when wet, they do not keep you as warm when they are wet and can often leave you feeling clammy if the material doesn’t have airflow to dry. I grabbed a pair of REI brand kid base layer pants for myself on clearance and I like the fit and feel of those better than my more expensive Smartwool bottoms. TMM Team Member Cait Shred Dog/Akova Our tester wore this on a thru-hike of Arizona’s 480-mile Mogollon Rim Trail in October and an Iceland traverse in August and raved about the Wolverino. Its durable mix of itch-free wool, and fast-drying synthetic fibers and design features gave us everything we want in a base layer. Some base layer brands understand that people of all sizes love getting outside. Some brands still have yet to get the memo. Smartwool and Patagonia have the broadest range of sizes available, including plus sizes and kids’ sizes. Do you want base layers tight or loose?

Team members also mentioned that Reima base layers are more affordable than other brands and love having an option that’s high quality but doesn’t break the bank. The Cool Daily is also treated with a Polygiene anti-odor technology called HeiQ® Fresh Durable Odor Control, which seemed to work even after a week of continuous use. The fabric is 50% recycled, bluesign certified for environmentally-friendly dying, and sewn in a Fair Trade factory.For a lightweight, affordable, and highly UPF-protective base layer, we think the Mountain Hardwear Crater Lake Hoodie is the best of all worlds. With a UPF rating of 50+, the lightest and thinnest fabric we tested, and sizes ranging from XS-3X, the Crater Lake hoodie is everything we want in a base layer for hiking. The Mountain Hardwear Crater Lake Hoodie is our winner for Best Base Layer for hiking. It's also the overall winner in our Best Sun Shirt guide.As a 100% synthetic base layer, it’s also suitable for vegans or people allergic to wool.

It doesn’t matter how good (or how inexpensive) a base layer is if it doesn’t fit you properly! Most brands have sizing that ranges from XS to XL. Patagonia, Smartwool, Columbia, The North Face, and REI Co-op have more inclusive sizing, ranging from 2XS to 3XL. As more people like Jenny Bruso from Unlikely Hikers speak up about how tough it is to find plus-sized outdoor gear, we’re hopeful that more brands will step up.What is it? Fear not, it’s not akin to your favourite woolly jumper. Merino wool is lighter in weight than traditional wool, and its temperature-regulating properties make it perfect for base layers. We love the Patagonia Capilene Midweight and think it shines as a running base layer. It's the best synthetic base layer out there, with decades of refinement and perfection. This synthetic base layer is versatile, suitable for wearing by itself or layering under a mid-layer. While there are less expensive synthetic base layers, the quality and durability (not to mention relative eco-friendliness) of the Capilene Midweight make it the best choice for synthetic. Sustainability has become an increasingly prominent focus within the outdoor industry, and this commitment extends to base layers. In the current landscape, two significant sustainability trends have emerged, reshaping how we think about base layer materials. Responsible Wool Sourcing What we liked: Versatility, durability, most inclusive sizing, looks good on most people, color and pattern availability, reasonably priced For a decade, our team of experts has bought and tested dozens of the best base layers on the market. For this update, we compare 17 of the most popular options side-by-side. From the ski slopes to alpine climbs to sleeping out under the stars, our in-depth analysis derives from real-world adventures undertaken while wearing each model. We score all base layers across key areas of performance, like warmth, breathability, and drying speed. Whether it's for the warm or cold season, a quality base layer is sure to keep you dry and comfortable, no matter where your next outdoor escapade takes you.

Lightweight wool layers are often labeled as 100 merino wool or 150 merino wool weight. Those numbers refer to the approximate fabric weight of the material in grams per meter (g/m)-so these layers are often the lightest piece of clothing in your outdoor wardrobe. A synthetic lightweight layer is often labeled “lightweight” because they’re usually heavier than their wool counterparts. MIDWEIGHT

Analysis and Test Results

Keeping your base layers in tip-top shape will allow them to perform better, last longer, and give you some good resale value on those expensive merino wool pieces. Iksplor base layers– use code MTNMAMA20 for 10% off Merino Care While we may love the fabric of a base layer top, if the base layer bottom doesn't fit right, it won't feel comfortable. Worse yet, with a merino base layer bottom, we've sometime seen the same fabric we love for a top not have enough stretch for a bottom…and to develop holes in unfortunate areas. What we liked: Softness, comfort, fit, sleeves and torso that are long enough, performance and good looking, stylish Synthetic base layers are most often made of polyester, nylon, spandex, etc. They come in a wide range of styles, price points, and technologies, like adding silver to aid in antimicrobial properties. Some people, myself included, love the coverage that a hood on a base layer provides. It’s easy to fine-tune my temperature as needed when I’m on a run or protect myself from wind or mild weather.

Not only is the Patagonia Capilene Midweight relatively affordable compared to other technical base layers, but they come in a broad range of colors and a more comprehensive size selection than most companies offer, ranging from XXS to 2XL (or 3XL in men's). They even have kids’ sizes if you want the whole family to match! As more outdoor brands are offering plus-size options, we hope that Patagonia will add at the very least a 3X to women's and more sizes, too. If you’ve also been on the fence on whether quality base layers are worth the investment then this post is for you. Below is a list of favorite base layers for kids of all ages with input from the entire Mountain Mama Team. To test the Patagonia Capilene Midweight, I wore this base layer against the skin during an October trail running traverse of the Wasatch range. The temperatures ranged from highs in the 70s to lows in the high 30s. I wore just the Capilene Midweight from 6 am to 8 pm when I added a Patagonia Houdini wind shirt to ward off the cold. That was perfect until 3 or 4 am when I added a fleece on top of that. For 2023, it is made with ZQ-certified merino wool to ensure environmental, social and economic sustainability while safeguarding animal welfare. In addition to traditional colorways, it’s also available with plant dyes, which we love.

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Caring for wool base layers can get a little, well, wooly. Some, like Smartwool and Icebreaker merino, are formulated to handle regular detergent. Others may require special detergents, like a specific wool wash, for optimal performance. Wool especially is prone to shrinkage in the dryer. If you live in a humid climate, you might want to lean more towards synthetics or wool blends for your base layers. DO YOU WANT A HOOD OR THUMB LOOP ON YOUR BASE LAYER?