EXIsport thermal underwear: how to choose a functional second skin for sports and winter

When it gets cold, the first layer on the body decides whether we really enjoy sports or a winter walk. High-quality thermal underwear works like a second skin - it wicks away sweat, maintains a stable body temperature and increases comfort even during strenuous exercise. At EXIsports, we help customers choose the right functional underwear for skiing, hiking, running, or just commuting to work in the cold.

In our offer you will find thermal shirts, underwear and complete sets for men, women and children. We will explain what thermal underwear is , what is the difference between merino and synthetics, how to choose according to activity and season, and how to care for it so that it lasts for more seasons. The goal is that thanks to EXIsport you will be able to put together your own functional "second skin" that will support you with every movement.

What is thermal underwear and why do you need it when doing sports?

Many people still compare thermal underwear to a classic cotton T-shirt or sweatshirt. However, cotton absorbs sweat, takes a long time to dry and creates a cold, uncomfortable feeling on the skin. A sweatshirt, on the other hand, belongs to the insulating layer, not directly on the body. Functional thermal underwear is designed as a thin, tight-fitting first layer that effectively wicks moisture away from the skin and helps the body regulate temperature better.

It works by moving sweat away from the skin to the upper layers, where it evaporates. With the right choice, you will feel dry and warm even when the intensity of your movement changes. EXIsport thermal underwear is therefore ideal for active people in cold weather - from recreational runners to performance skiers.

•        Sweat wicking: faster drying compared to cotton.
•        Thermoregulation: helps maintain a stable body temperature.
•        Comfort: tight fit, flat seams and elastic materials do not restrict movement.
•        Hygiene: functional and merino materials smell less and are easy to maintain.

To be sure you're getting proven materials and cuts, choose from our wide range of functional base layers . We've listed each product for both sport and temperature conditions so you know exactly where it will work best.

How to choose the right EXIsport thermal underwear according to your activity

Not every thermal shirt is universal for everything. A skier who alternates between skiing and standing in line for the lift has different requirements, and a runner who has a high heart rate and sweats a lot has different requirements. At EXIsports, we therefore recommend always starting with the question: What activity will I wear thermal underwear for most often?

Accordingly, you can choose models for skiing, hiking, running, cycling, or regular wear in the city. In our e-shop, you can conveniently filter thermal underwear by sport, season, and purpose, so you can quickly find the ideal pieces for your activity.

For intensive activities (running, alpine skiing, fast hiking), we prefer lighter and faster-drying pieces. For less active activities (walking, Christmas markets, standing at the stadium), we recommend warmer sets that insulate better. In the categories at EXIsports, you can select thermal underwear for skiing, hiking or running through filters, so you can shop exactly according to your plans.

If you are unsure, it is worth starting with a universal set and gradually adding specialized pieces according to the sport. In practice, we see that customers who invest in a quality base layer once, return to it every winter.

Thermal underwear for skiing and snowboarding

A skier spends many hours on the slopes, alternating between active skiing and passive standing in line or on the ski lift. That's why they need thermal ski underwear that warms but also breathes. Warmer thermal underwear with a higher weight, often with a blend of merino wool, is ideal, as it retains heat better even in frost and wind.

Under a ski jacket, we recommend a set - a long-sleeved thermal T-shirt and thermal underwear. In our offer you will also find specialized models marked for use "on the slope", which are tested at low temperatures. When choosing, it is worth looking at the reinforcement zones, a higher waist on the pants and an extended back of the T-shirt so that the wind does not blow on your lower back when moving.

•        Warm sets with merino wool for multi-day skiing.
•        Multiple knitting zones for support in critical areas (back, knees, hips).
•        Breathable panels in the armpits and on the back to wick away sweat while riding.

Thermal underwear for running and intensive training

When running and intense training, the biggest problem is sweat. The body heats up quickly, sweats, and cools down very easily when you stop. That's why breathability and quick-drying materials are key. Thinner synthetic pieces with flat seams and a tight cut that don't chafe even on long runs are the best.

For runners and performance athletes, we recommend the "light second skin" style - a long-sleeved thermal T-shirt that fits close to the body, quickly wicks away moisture and lets you breathe freely. For very intense training in winter, a thin thermal T-shirt, a light sweatshirt and a windproof jacket on top are often enough. You can find such pieces in the category of functional sports T-shirts for winter in our offer.

•        Lightweight for quick moisture wicking.
•        The elastic material does not restrict strength or running movements.
•        Flat seams for chafing-free comfort even during long workouts.

Thermal underwear for winter hiking and outdoor activities

Winter hiking, sledding with children or long walks in the city have a common feature - a long stay in the cold with varying intensity of movement. Here you need a balance between warmth and breathability . Thermal underwear should not overheat when climbing uphill, but at the same time it should warm you up during a short break.

Combined materials (merino + synthetics) work very well here, combining the natural warmth and antibacterial properties of merino with the durability and quick drying of synthetics. At EXIsports, we often recommend such sets to families who spend a lot of time in the mountains and want one universal piece for various outdoor activities.

•        Combined knits for long wear without odor.
•        The elongated cuts protect your back even when bending forward.
•        You can use universal sets for hiking, sledding and the city.

Thermal underwear materials: merino wool vs. synthetics

When choosing thermal underwear, we almost always come to the question: merino or synthetic? Both solutions have their advantages and it is ideal to know when to reach for a natural wool piece and when for synthetic, highly functional underwear. At EXIsports you will find pure merino, synthetic and combined sets, so that everyone can choose according to their priorities.

Merino wool excels in excellent thermoregulation and natural odor resistance, while synthetic fibers are extremely quick-drying, durable, and often cheaper. For active athletes, hybrid pieces that combine the best of both worlds are also very interesting.

If you are looking for maximum comfort on multi-day trips without the possibility of washing, reach for merino thermal underwear . If you need a highly functional piece for training where you sweat a lot, synthetics will be ideal for you. Combined materials are a great compromise for those who exercise often and in different conditions.

In the product descriptions at EXIsports we always state the exact composition and recommended use so that you can see whether a given shirt or pants fits better for a skier, runner or general user. If you are unsure, we are happy to advise you directly in store or via customer support.

Benefits of merino thermal underwear

Merino wool is a legend among athletes. It is natural , warm and thanks to the special structure of the fiber, it can absorb a lot of moisture, while still feeling dry on the skin. At the same time, merino has natural antibacterial properties , so even after several days of wearing it does not smell like regular synthetics.

We recommend merino thermal underwear for skiing, winter hiking and longer stays in the mountains, where you don't have the opportunity to wash your clothes often. It is ideal for those who prefer comfort and warmth over extreme drying speed. At EXIsports you will find several models made of merino wool in men's, women's and children's versions.

•        Excellent thermoregulation - warms in the cold and does not overheat in the heat.
•        Odor resistance – suitable for multi-day trips.
•        Pleasant touch – the fine fiber does not scratch and is comfortable on the skin.

When to choose synthetic thermal underwear

Synthetic thermal underwear is ideal for those who exercise intensively and frequently. Polyester or polyamide fibers are very durable, dry quickly and can withstand repeated washing without changing their functional properties. For teenagers, children and recreational athletes, this is a practical and affordable solution.

We recommend it for running, alpine skiing, dynamic training or fitness in cold weather. In the EXIsports offer you will find entire sets of quick-drying thermal underwear, which you can simply wash after training and the next day it is ready for another activity. Thanks to easy washing, synthetics are also ideal for families with children who need functional pieces for kindergarten, school or ski courses.

•        Quick drying - ideal for frequent training.
•        Lower price - a convenient choice for multiple children in the family.
•        High durability – can withstand frequent washing and intensive wear.

Men's thermal underwear EXIsport - what men deal with most often

When choosing thermal underwear, men most often ask about three things: freedom of movement , durability and price/performance ratio . They want the underwear to last the entire winter season, to be comfortable to move in while doing sports and not to have to have ten different sets in their closet. That's why at EXIsports we offer men's thermal T-shirts, thermal pants and complete sets that meet these requirements at different price levels.

Men's models are often geared towards skiing, hockey, winter running or hiking. In our category of men's functional winter sets, you will find basic pieces for recreational wear as well as more technical models for more demanding athletes. For each product, we list the recommended type of activity and level of insulation so you can quickly find your way around.

•        Men's thermal T-shirts - long sleeves, various thicknesses and knits.
•        Men's thermal pants - higher waist, reinforced zones.
•        Complete sets - T-shirt + pants in one design.

How to choose the right size of men's thermal underwear

The right size is key to making thermal underwear feel like a second skin . The first layer should be snug, but not uncomfortably tight. If it's too loose, cold zones will form and the material won't wick sweat away as well. If it's too tight, it restricts movement and can cause pressure in the shoulders, chest, or waist.

We recommend measuring your chest, waist and hips at home and comparing these values with the size chart of a specific brand. At EXIsports, we provide details about the cut (slim, regular) for products and, for several models, also customer recommendations on whether the product "fits standard" or is rather smaller or larger.

If you are hesitating between two sizes and prefer a more sporty fit, you can choose the smaller size. If you have a wider body or prefer a slightly looser feel, go for the larger size. The advantage of buying from us is the possibility of exchanging the size if the first choice does not fit you perfectly.

EXIsport women's thermal underwear - comfort, cut and design

When choosing thermal underwear, ladies consider not only functionality but also cut , length of the T-shirt , waist height and of course design . Women's models at EXIsports are designed to copy the female figure, not to roll up and protect sensitive areas from the cold. The softness of the material on the skin is also important so that it does not cause irritation.

Women's thermal underwear is suitable not only for skiing or cross-country skiing, but also for wearing in the city under a coat or walking with children. In our category of women's thermal clothing for winter, you will find models in seasonal colors, with feminine cuts and patterns that look sporty and elegant at the same time.

•        Longer shirts protect the lower back from the cold.
•        The high waist on the pants increases comfort when sitting and moving.
•        Soft material , pleasant to the touch, suitable even for sensitive skin.

Women's thermal underwear sets - when everything matches

Complete sets are very popular when it comes to women's thermal underwear - a T-shirt and underwear in the same design and material. They provide the assurance that everything matches together functionally and visually. At EXIsports, we often recommend sets to our customers as a great buy for a skiing holiday, a winter stay in the mountains or as a practical gift.

Sets make sense wherever you need to be sure of the same functional properties of the top and bottom. This will prevent situations where the t-shirt is too thin and the bottoms are too warm, or vice versa. Just choose the right weight and arrange the remaining layers accordingly.

•        Uniform material – equal warmth at the top and bottom.
•        Elegant design - also suitable as a gift.
•        A practical purchase – one set will cover most winter activities.

EXIsport children's thermal underwear - warmth and movement for the little ones

Children move quickly outside, often sweat and catch cold very easily. Therefore, quality children's thermal underwear is essential if we want them to enjoy the winter without colds and illnesses. At EXIsports, we offer models for the smallest children and teenagers, with cuts adapted to their body type and activities.

Younger children will appreciate soft, warm materials and cheerful colors, while teenagers prefer a sportier look and thinner material for intense movement. In the children's thermal clothing for winter category, you will find sets suitable for ski courses, winter school events and weekend family trips.

•        Quick drying - ideal after a ball game or sledding.
•        Gentle materials – suitable for sensitive baby skin.
•        Durable workmanship - can handle jumping, falls and frequent washing.

How to dress children in three layers for winter

The 3-layer system applies to children just like it does to adults, but it is even more important that they can move freely. The first layer is functional thermal underwear that wicks away sweat and keeps the skin dry. The second layer insulates – typically a fleece sweatshirt or light down jacket. The third layer protects against wind, rain and snow – a ski jacket or waterproof parka.

For ski courses, outdoor school or winter school activities, we recommend having at least one quality set of thermal underwear that can be combined with various sweatshirts and jackets. If your child is more prone to cold, it is worth choosing a thicker weight or merino, while for active children, thinner, more breathable pieces.

•        First layer – functional thermal underwear.
•        Second layer – insulating sweatshirt or sweater.
•        Third layer – waterproof and windproof jacket.

Cut and construction of thermal underwear: what to look out for

In addition to the material , the cut and construction also determine comfort. There are tight compression cuts that support muscles and minimize vibrations, and looser functional cuts that are comfortable for everyday wear. When choosing, it is important to consider whether you want a performance or a more versatile piece.

When it comes to EXIsport thermal underwear, it's worth paying attention to the details: flat seams, seamless processing in sensitive areas, sleeve and leg length, and waist height. Good construction will reduce the risk of chafing, keep the sleeves and legs in place, and ensure that it won't blow on your lower back even during intense movement.

•        Flat seams – fewer pressure marks and abrasions.
•        Seamless zones – comfort in the armpits or inner thighs.
•        Correct length – sleeves and pants do not roll up.

Thermal underwear as a "second skin"

Well-fitting thermal underwear feels almost like a second skin . It doesn't move, doesn't roll, doesn't press anywhere, and doesn't restrict your movement. With the right size and cut, there are no pilling, the material doesn't dry out in places of friction, and it remains comfortable even after several seasons of use.

Investing in a better cut and material always pays off in practice. Customers often tell us that after trying a better model, they stop wearing old cotton T-shirts under their jackets – the difference in comfort is simply too big. That's why at EXIsports we make sure to keep proven models in our offer that have proven themselves in real use.

Clothing layering: how to wear thermal underwear EXIsport

Proper layering is key to staying warm and not too cold. The 3-layer system seems simple: first layer thermal underwear, second insulation layer, third protective layer. The key is to choose the right thickness of each layer based on the activity and temperature.

For skiing, a combination of warmer thermal underwear, a fleece sweatshirt and a ski jacket may be appropriate, for milder hiking, a thinner thermal T-shirt, a light insulating layer and a softshell jacket. Thanks to quality thermal underwear, you often don't need "many layers", but rather two to three functional levels, properly stacked.

•        First layer – sweat wicking and temperature regulation.
•        Second layer – insulation according to activity intensity.
•        Third layer – protection from wind, rain and snow.

Common layering mistakes

The most common mistake is wearing a cotton T-shirt under or instead of thermal underwear . Cotton absorbs sweat and stays wet, so even the best jacket cannot prevent you from getting cold. The second mistake is wearing too many layers – the body overheats, sweats, and cools down quickly when you take off a layer.

When shopping at EXIsports, we therefore recommend that you think about the entire outfit, not just one piece, right when trying it on. A properly chosen first layer will allow you to wear less clothing, but you will still feel warm and dry. If you are unsure, we will advise you on which combinations to avoid and how to put together an effective layering plan according to your sports plans.

•        No cotton as a first layer when exercising.
•        Better 3 functional layers than 5 non-functional ones.
•        The right size of each layer so that they don't interfere with each other.

Thermal underwear care: washing, drying, lifespan

Even the best thermal underwear will lose its functionality over time if it is not cared for properly. The basic rule is: wash according to the manufacturer's recommendations, use moderate temperatures and avoid fabric softener . Fabric softener glues the fibers together, reduces breathability and prevents effective sweat removal.

Merino wool will appreciate special wool detergents and delicate programs, while synthetics can handle a regular sports program at lower temperatures. It is best to dry thermal underwear freely in the air, away from direct heat sources. With proper care, you will significantly extend the life of your favorite sets from EXIsport.

•        Washing inside out – protects the surface of the knitwear.
•        Without fabric softener – preserves the functionality of the fibers.
•        Air dry – not on a radiator or in a powerful dryer.

The most common mistakes when maintaining thermal underwear

The biggest mistakes include washing at too high a temperature, drying in a dryer on a high setting, ironing and using fabric softener. All of these steps can cause the thermal underwear to lose its functionality , change its shape or destroy the elastane in the fiber. In addition, merino wool can shrink and reduce softness.

At EXIsport, we advise customers to take a few seconds to read the label before putting their thermal underwear in the washing machine for the first time. We also recommend washing functional pieces separately from classic clothing so that they do not get caught on zippers or Velcro fasteners. With proper maintenance, you can extend the life of your favorite set by several seasons.

How to choose EXIsport thermal underwear according to the season

Thermal underwear is no longer just for the coldest weather. At EXIsports you will find models for winter , transitional seasons (spring/autumn) and year-round sportswear. The difference is mainly in the thickness of the material, weight and breathability. Therefore, depending on the season, you can have several types of functional underwear in your closet.

For freezing winter, we recommend thicker, warmer sets, and for spring and autumn, lighter, more breathable pieces that can also serve as a separate layer at higher temperatures. All-year thermal shirts are ideal for outdoor activities where conditions change quickly and you need a universal solution.

When buying, it is also worth looking at the recommended temperatures, which many brands list directly on the label. At EXIsports, we will be happy to advise you whether a particular model is more suitable for January skiing or rather for cold autumn training.

Thermal underwear for recreational and performance athletes

The recreational athlete is mainly looking for comfort , versatility and a reasonable price . The performance athlete is more concerned with details - breathability, zonal knitting, compression or material weight. At EXIsports, we have experience that it is precisely according to this division that it is very easy to help you choose the right set.

For recreational athletes, we often recommend a universal set that they can use for skiing, hiking, and winter walks. For performance athletes, we help them combine more specialized pieces – for example, a lighter T-shirt for running and a warmer set for long ski trips. In practice, we have found it useful to recommend basic equipment first and then add special pieces according to specific training plans.

•        Recreational athlete – universal set, great price.
•        Performance athlete – more specialized models by sport.
•        Family shopping – a combination of children's, women's and men's sets in one order.

Thanks to our range of thermal clothing for cold weather, you can put together equipment for the whole family - from the first sports attempts to demanding winter training. Our salespeople solve specific customer situations every day and can recommend proven combinations from practice.

How to buy EXIsport thermal underwear online - practical tips

Buying thermal underwear online is very easy thanks to detailed descriptions and size charts. All you need to do is know what sport and temperature you are looking for thermal underwear for, measure the basic dimensions and look at the material parameters. At EXIsports, we provide information about the thickness, sport designation, cut and recommended conditions for the products.

When shopping online, we recommend reading the product description carefully, looking at the size chart, and checking reviews from other customers. Thanks to filters by gender, age, sport type, and brand, you can quickly narrow down your selection to a few ideal candidates. The advantage of shopping with us is also the possibility of exchanging sizes and frequent discounts on seasonal thermal underwear sets.

•        Read the descriptions - you will learn what the product is intended for.
•        Check the size charts - you will minimize the need for replacement.
•        Use filters – you will save time when searching for the right model.

FAQ

How to choose the right EXIsport thermal underwear for winter?

When choosing a winter set, first think about what activity you will use it for most often. For skiing or long stays in the cold, we recommend warmer thermal underwear with a higher weight, or with a share of merino wool . For running or intensive training in winter, it is better to choose thinner, breathable models that quickly wick away sweat. Also follow the product descriptions in EXIsports, where we list recommended temperatures and sports, and don't forget to choose the right size and cut so that the thermal underwear works like a second skin.

What is the difference between merino and synthetic thermal underwear?

Merino thermal underwear is natural, very warm and has excellent odor resistance, so it is ideal for wearing for several days without washing. It dries a little slower, but even slightly damp it still warms. Synthetic thermal underwear is extremely quick-drying , durable and often more affordable, which is especially appreciated by active athletes and families with children. If you are looking for a compromise, combined materials that combine the warmth of merino with the functionality of synthetics are also suitable.

What thermal underwear is best for skiing in EXIsport?

For skiing, we recommend warmer sets of thermal underwear with a higher weight, which can handle long stays in the cold and alternating between riding and standing. Models with merino or combined materials have proven very successful, which insulate well but remain breathable at the same time. Also important is the elongated cut of the T-shirt so that it does not reveal the buttocks, and a higher waist on the bottoms . For products in EXIsports, look for labels for skiing or snowboarding, where manufacturers already take into account typical conditions on the slope.

How should men's and women's thermal underwear fit correctly?

The right size should feel like a second skin – the thermal underwear fits snugly, but does not press or restrict movement. The T-shirt should not pull excessively in the shoulder area or when raising the arms, the pants should have a comfortable waistband that does not cut in. If the first layer is too loose, sweat drainage is impaired and cold zones form. At EXIsports, we therefore recommend measuring your basic circumferences and comparing them with the size chart of a specific manufacturer.

How to wash and maintain thermal underwear so that it does not lose its functionality?

Always wash thermal underwear according to the manufacturer's label , most often at lower temperatures on a gentle program. The key is to avoid fabric softener , which glues the fibers together and reduces breathability. Merino pieces are worth washing with a special wool detergent and drying freely in the air. Synthetic models can handle more frequent washing, but it is also advisable to dry them without using a hot dryer. By following these principles, EXIsport thermal underwear will maintain its functional properties for a long time.

Is merino thermal underwear also suitable for intensive running?

Merino thermal underwear can also be used for running, especially in freezing conditions or during moderate activity. It is very comfortable, regulates temperature well and smells less. However, for very intense running and heavy sweating, many runners prefer synthetic, quick-drying models that wick away moisture even faster. Thinner merino or combined materials that combine the comfort of wool and the functionality of synthetics can also be an ideal solution.

What EXIsport thermal underwear is suitable for children on ski courses?

For ski lessons, we recommend a complete set of thermal underwear for children - a long-sleeved T-shirt and underwear. It is important that the material is pleasant to the skin , dries quickly and is warm enough. For younger children, soft sets with warm knitwear are an excellent choice, while for older schoolchildren, more functional, sporty models are more suitable. At EXIsports, you will find children's thermal underwear designed specifically for skiing, which can handle a full day on the slopes and frequent washing after returning home.

How many layers of clothing do I need when I have quality thermal underwear?

If you have high-quality functional thermal underwear , you often only need three well-thought-out layers . The first layer wicks away sweat, the second insulates according to the temperature and intensity of movement, and the third protects against wind and moisture. In practice, this can mean a thermal shirt, fleece sweatshirt and ski jacket, or a thinner thermal shirt and a light jacket for running. More layers of non-functional materials often cause overheating and more sweating, so the quality and function of the individual layers are more important than the number.

How to choose the size of thermal underwear when buying online at EXIsport?

When buying online, we recommend taking a tape measure and measuring your chest, waist and hips . Then compare this data with the size chart for a specific product in EXIsports. If you are hesitating between two sizes, a more sporty cut will usually tolerate a slightly tighter version, while a universal fit will tolerate a slightly looser version. Customer reviews can also help, where you can often find information about whether the product fits standard, smaller or larger than usual.

Can one set of thermal underwear cover multiple sports and seasons?

Yes, a well-chosen universal set can handle multiple sports and multiple seasons, especially if you go for a medium weight. You can use such a set for skiing, hiking, and everyday wear in the city, just change the second and third layers according to the weather. Performance athletes often buy an even lighter T-shirt for intensive running or training. When choosing at EXIsports, it is worth considering which activities make up most of your year, and choose a more universal or specialized set of thermal underwear accordingly.