Winter is coming in full force and that means colder weather is approaching! When preparing for your next outdoor adventure, a quick thermal check can make or break your entire experience. Surprisingly, there is quite a bit of science that goes into layering, and it can get confusing with so many brands! Below, we will dive into the science behind regulating your body temperature and the best layers to add to your holiday list this season!

Why do some people get hotter or colder than others? Have you ever been out in the cold weather and your hands are freezing, but your friends are totally fine? Definitely unfair, however, it all comes down to the circulatory system in our body. When someone feels really hot, their blood vessels are dilated, meaning that blood flow to the skin is increased. Consequently, that extra heat is released. Similarly, when someone is cold, their blood vessels are constricted. This causes the blood to move inward, away from the skin and towards the vital organs. Therefore, anything that interferes with your body’s circulation system will affect your core temperature.

When it comes to layering, this matters a ton! If you can learn how to keep your circulatory system regulated and in check, your adventure outside will be much more enjoyable. Don't be the jerry that shows up in a t-shirt. Extra warmth and weather protection is crucial! So how do we keep our body temperature regulated? We will dive more into that below!

Choosing your layers for an outdoor adventure is critical to having a successful trip. Too many times, I have forgotten a vital layering component that ended the day. In deciding what layers to bring, you first need to check in with your own body. Are you someone that runs hot? Do you tend to sweat a ton? Do you barely sweat? Do you find yourself freezing all the time? Noticing your body’s subtle, but simple, clues will help you make the best decisions when it comes to layering! It also will help you choose the correct fabrics and materials. Making informed choices with your gear is imperative for comfort on the slopes. There are three vital layering components when going outside:

1. Baselayer: Moisture Management
2. Middle Layer #1: Insulation
3. Middle Layer #2: Insulation
4. Outer (or Shell) Layer: Protection from Elements

Now that you know the basics to garments, let’s dive into each one! These are the ingredients for an awesome downhill experience every time. My hope is that you will come out of this by making smarter consumer decisions that are tailored to your body’s individual needs.

Baselayer: Moisture Wicking Management

One of the most important layers is the baselayer (aka long underwear). When choosing a baselayer, we want to keep three ideas in mind:

• Fabric: What is the base layer material made out of?
• Fit: How snug is it against your body?
• Weight: Heavyweight, midweight, or lightweight?

Fabric

Keeping these three things in mind, let’s first talk about the best baselayers. Fabric and material is everything when choosing a baselayer. If you have ever heard the term, “cotton kills,” you know why! For the base layer, the fabric is so important because it is that moisture-regulating layer. You want to find a fabric that is going to do a good job at regulating your body’s temperature by wicking away perspiration from the skin—choosing good wicking properties in fabrics will keep you on the slopes and enjoying that fresh powder longer.

Fabrics that are excellent in this department are synthetics (polyester and nylon), merino wool, and silk. The fabric should be light, long-sleeved, and close to your skin. Thinner materials do a better job at wicking away moisture, so keep this in mind if you prefer not to have material close to your skin! Below, I will list the most common types of baselayer fabrics and the pros/cons:

Synthetics Fabrics (Polyester, Nylon, Blend of Materials)

• Pros: Great at wicking away moisture. If you tend to be a really sweaty person, go with a synthetic base layer and it will keep you dry. This fabric is also very strong and durable. A midweight base layer in this material is very popular.
• Cons: Can sometimes obtain more odor than other fabrics.

Merino Wool

• Pros: Cooling, wicks away moisture, light and comfortable feel, and is resistant to odor. Choose a lightweight baselayer top to match merino wool pants for efficient temperature regulation. Sometimes made with spandex materials for a better midweight baselayer fit.
• Cons: Not as durable as other fabrics. Won’t feel as dry as its synthetic cousin.

Silk

• Pros: Odor retention and extremely lightweight. Great for spring skiing.
• Cons: Not very durable.

Fit

Now that you know a little more about material, let’s talk fit. A baselayer should be tight! This will ensure that it can do its job correctly by wicking away any unnecessary moisture. The goal is to make sure zero dead space can get between your baselayer and your body. If you have dead space, this will defeat the purpose of this layer!

Weight

Lastly, we look at weight. Weight is typically categorized into three categories: lightweight, midweight, and heavyweight. Weight is important because it largely depends on the activity that you are doing. If you are going to be resort skiing in below zero temps, you should choose a heavyweight option. If you are going to be backcountry skiing through the snow in the spring, maybe opt for a lightweight option. The goal is not to get too hot or cold! Depending on the activity, the weather, and your own personal metabolism, you should be able to make a judgment call on which weight to bring out for which activity.

Some tips/tricks when choosing your baselayer:

• Find long-sleeve shirts with thumbholes or thumb loops. This makes sure cold air won’t get between your gloves and jacket.
• If you remember one thing from this entire article: Cotton kills! Don’t even think about adding it to your baselayer closet. Cotton absorbs and traps moisture keeping you cold. While this sounds appealing in the summer, it’s a big NO in the winter.
• Choose tight-fitting, long sleeves.
• Make sure you understand your metabolism—this helps determine your layering weight.
• Choose a material that is right for your body temperature and individual needs!

Middle Layers: Insulting Layers

So now what? You have a baselayer that handles your sweat, and you understand your body’s metabolism and general temperature fluctuations. Next, you need the insulating layers! Brands like Rab and Patagonia offer great options that provide versatility and mobility. The best midlayers will work with your own body heat to keep you warm. I recommend having two insulating layers, however, this is a personal preference.

The goal of these two layers is to trap dead air space and keep you warm! Your body is constantly radiating heat. The heat that makes it past the baselayer, without all of that moisture, needs to be trapped to keep you warm, and thus, the insulating layers play a role. I typically like to have two insulating layers: a light fleece and a down puffy jacket. The benefit to this is that you have two layers acting to trap dead space instead of just one. I find that if I just put a puffy over my baselayer, there is too much dead air space, and I’m actually colder. You are looking for a mid-layer that is lightweight, insulating, and breathable! With those things in mind, let’s dive in—here are common middle layers and their pros/cons:

Fleece

Fleece is awesome! One of the best things about fleece is that it stays warm even if it gets a little damp. Fleece jackets have some efficient insulating power with heavyweight, midweight, and lightweight options. Again, choosing which is right for you depends on your metabolism and the activity you will be doing. Fleece is usually made with polyester fibers and tends to be a bit bulkier and heavier than other fabrics. A simple fleece hoodie can be great from the first lift to the apres-hangs.

Wool

Wool is a great insulating layer. This fabric is very versatile in that it is breathable, yet stays warm when wet. Keep in mind that it does tend to be bulkier, so if you are aiming for that real lightweight option, wool probably isn’t your best option.

Down Puffy: Synthetic Down and Authentic Down

Synthetic Down: Polartec Alpha, PrimaLoft, and Climashield are all types of synthetic down. Synthetic down is usually a lot cheaper than authentic down (down), but it still has great insulating power. Synthetic insulation tends to be a bit bulkier, so it is harder to pack into small backpacks. Synthetic material also is said to be a little less warm than down, however, depending on where you live, this might be a perfect option. If you are in warmer climates that rarely drop below freezing, a synthetic option might be perfect for you! This material is a little less durable than its down counterpart.

Authentic Down: Light, breathable, easy to compress, and long-lasting, down puffy jackets are a huge hit. Fill power is used to determine the down jacket’s ability to loft and trap heat. Thus, the higher the fill power, the warmer the jacket. Fill power is calculated by how many cubic inches one ounce of down feathers can fill in a testing device. For example, 600-fill-power down means that one ounce of that down fills 600 cubic inches of space. The higher you go in fill power, the less amount of down you need to fill a certain space. It's added bonus: down has an excellent warmth-to-weight ratio. One of the biggest disadvantages of down is that it loses its ability to insulate when it gets wet, and it takes a long time to dry.

Pro tip: if your down jacket gets wet, throw it in the dryer with a few tennis balls on low heat. This will help the down fill keep its natural fluff!

Keep in mind that there are many different types of insulating layers, based on style. You could choose layers with hoods, vests, hooded coats, zippered jackets, pullovers, etc. which all do the same thing. Choosing type configuration is largely dependent on your own personal style!

Lastly, keep weight in mind. If you choose a midweight baselayer, maybe only do one insulating layer. If you want to do a lightweight baselayer, with another loose-fitting midweight baselayer, and then a down jacket as your midlayer, this is acceptable! You can mix and match styles and fabrics, as long as you stick to the general guidelines. Ultimately, finding what works best for your body is going to be your ticket to a successful day spent outside.

Outer (or Shell) Layer: Element Protection

Last but not least, we have the outer layer or shell layer. This layer is your outdoor element protection superhero. Wind, rain, sleet, snow, hail—you name it—this layer should protect you over your insulating layers! The outer or shell layer tends to be water-resistant and breathable. Almost every outer layer is treated with durable water-repellent (DWR) finish to make water bead up and roll off the fabric. This is vital in keeping you protected from the elements and ensuring that your midlayers and baselayers stay dry. Look for options with a full zip, long hem, hand pockets, and snug cuffs to keep the elements at bay.

Without this layer, you get wet fast which then ruins the efficiency and insulting qualities of all the other layers discussed above. In other words, you get cold—fast! Staying dry is key to a fun day in the mountains. For this layer, we are looking at two major things: how well it retains warmth created by your other layers and how well it will keep you dry.

There are a few types of outer or shells layers to be aware of:

Waterproof, Breathable Shells

These are going to be your priciest option. Durability, compact-ability, and breathability all are factors that raise the price. However, if you are looking for a lightweight, stellar option for more rigorous (sweaty) outdoor activities, then a waterproof, breathable shell is your ticket! Brands like GORE-TEX have really changed the game with hardshell jackets, adding in more breathability than ever before.

Water-Resistant, Breathable Shells

These shells are going to be less expensive, because they are not fully waterproof, meaning that if you spend enough time outside, you will get wet. These options are great if you plan to go outside for a short amount of time. Look for that DWR treatment on these shells. If you are looking for a shell suited for high activity levels with some light weather, this will be perfect!

Soft Shells

These are all about breathability! These layers have the ability to handle light weather and wind protection. They are a great option if you are going backcountry skiing and need a little more outdoor protection, but won’t be out long enough to need a fully waterproof shell. Soft shells are awesome for spring skiing. Check out brands like The North Face and Arc'teryx.

Waterproof, Non-Breathable Shells

These are your typical rain jackets. They are meant for rainy days when you really need that extra protection. Keep in mind, though, that they are not breathable. The only problem with hard shells is if you choose a non-breathable option, your base layers underneath won’t be able to create a perfect micro-climate and you tend to feel wet and sticky without that breathability component. But in the wet weather and areas of high precipitation, that will be what you need!

Recap!

Now that you have a good idea of what a productive and efficient layering system looks like, I hope that your next trip outdoors will be much more enjoyable! To recap, here are some tips and tricks:

• Hoods, vests, adjustments, pockets, buttons/zippers, vents, and special features all largely determine the style of the layer, however, they can be hindering in breathability and movement, especially when worn for outdoor, rigorous activities.
• Know your body’s metabolism, core temperature, and circulatory system to make sure you are setting yourself up for a good day on the slopes.
• Pick layers and fabrics that cater to your unique body, but also the type and rigor of the activity you intend to do.
• Always try NOT to get to a point where you are already freezing or way too sweaty immediately out of the gate. As you shed layers when working out, make sure you throw on an insulating layer (i.e. a puffy down jacket) when you stop to keep that sweat from cooling on your body. Have a system and stick to it!
• If your core is warmed correctly, it will help bring blood flow and warmth to your other extremities. Therefore, spend a little extra this holiday season on layers that actually make you feel warm!
• Eat! Snack frequently on a cold day skiing. Eating helps kickstart your metabolism and warms your body.
• Invest in warm gloves and ski socks! Make sure you never leave ski boots in a cold car or your feet will automatically get cold the second you slip them in.
• Don’t forget the extra layers. Even if you think that it won’t rain or snow, it usually always does—so come prepared!

I hope this makes your layering decisions easier! If you have any questions, reach out to a Winter Sports Expert here on Curated. We'd be happy to help! Skiers, snowboarders, and outdoor enthusiasts alike, may we always continue to remember that there is never bad weather, only poor choices in layering.