Thermal underwear top: a layer of protection from the cold 

Winter in Russia is not just a time of year, it is a separate type of strength test. When the thermometer drops below minus twenty, and the piercing wind from the Neva or Moscow heights breaks through even the most expensive down jacket, it becomes obvious: the problem is not in outerwear. The problem is what's underneath. Many people still make the fatal mistake of wearing a cotton T-shirt or wool sweater as the first layer, sincerely believing that it is warmer. This is a myth that costs your health. Correctly selectedтермобелье верх: слой защиты от холода- this is the only thing that separates you from hypothermia and loss of comfort during winter fishing, skiing or just waiting for the bus at the bus stop. In 2025, the market is oversaturated with offers, from cheap Chinese synthetic knitwear to high-tech membrane systems from Scandinavian brands, but how not to drown in this stream of marketing and choose what really works in our harsh conditions? Let's figure it out without embellishment.

Why cotton kills heat: the physics of the process that sellers are silent about

Have you ever wondered why, after a vigorous ski trip, you start shaking as soon as you stop? It would seem that you were sweating, you were hot, your body was warmed up. But if you pause, the cold penetrates to the bones. The culprit of this betrayal is ordinary cotton fabric. Cotton is hygroscopic; it absorbs moisture like a sponge, but is completely incapable of releasing it. As a result, the fabric, wet from sweat, sticks to the body and begins to actively cool the skin due to evaporation. In the Russian winter, this is a direct path to a cold.

Real functional underwear works according to a fundamentally different scheme. Its task is not to warm (it is not a source of heat in itself), but to remove moisture from the body into the outer layer of clothing, keeping the skin dry. Dry skin = warm skin. This is an axiom that 80% of buyers ignore, focusing only on the thickness of the fabric. Modern materials used in the 2025/2026 season are capable of transporting up to 90% of moisture in a matter of minutes, creating a microclimate around the body that is independent of external temperature.

But here lies the first pitfall. Not all synthetics are equally useful. Cheap polyester, which is often sold under the guise of “thermal” in markets and online discounters, actually wicks away moisture, but at the same time creates a “greenhouse” effect. The skin doesn't breathe, condensation accumulates inside, and you turn into boiled crayfish. Real thermal underwear should have a complex weaving structure, often two-layer: the inner layer of hydrophobic material repels moisture, and the outer layer, made of a more hygroscopic material, transfers it further to the fleece or jacket membrane.

Thermal underwear top: a layer of protection from the cold for different activity scenarios

There is no universal solution. What will save a marathon runner in the cold will freeze a fisherman sitting motionless on the ice for five hours. A mistake in choosing the category of underwear can cost you your entire trip. Let's take an honest look at the three main types of activity and what underwear is required for each.

High activity.Cross-country skiing, ski touring, winter running, mountaineering. The main task here is maximum moisture removal. You produce enormous amounts of heat and sweat. If moisture remains on your body, you will overheat and then cool down quickly. For such purposes, thin, almost weightless models made of pure synthetic fiber (polypropylene, special polyester) with a minimum content of natural fibers are needed. The wool here will be superfluous; it takes too long to dry. The density of the fabric should be minimal so as not to create additional resistance to movement.

Average activity.Walking skiing, snowboarding, hiking, active games with children outside. This is the most popular scenario for most Russians. Here you need a balance between moisture removal and heat retention. The ideal option is mixed fabrics. Synthetics wick sweat, and the addition of merino wool or rayon provides a cozy feeling and additional insulation. Such models often have zonal weaving: in areas of increased sweating (back, armpits) the structure is looser for ventilation, and on the chest and abdomen it is denser to retain heat.

Low activity.Winter fishing, spot hunting, outdoor work, bird watching. This is where many people make the main mistake of wearing “breathable” thin underwear. If you don't move, you don't sweat intensely. What you need is heat preservation. Here the king is high-density merino wool or multi-layer systems with brushed inside. Synthetics in their pure form lose out here, since they do not heat on their own. However, all-woolen underwear also has a disadvantage: it takes a long time to dry if you do get sweaty when going to the fishing spot. Therefore, the best models for static rest are a combination: an inner layer of soft wool for comfort and an outer layer of synthetics to drain excess.

Market 2025: battle of technologies and price chaos

The situation on the Russian thermal underwear market has undergone enormous changes over the past year. The departure of Western giants like Craft, X-Bionic or Icebreaker has left a huge niche that local manufacturers and brands from friendly countries are rushing to fill. But do they fill it efficiently? My monitoring of new products at the end of 2024 and beginning of 2025 shows an alarming trend: under the guise of innovation, we are often sold old technologies in new packaging.

Russian brands, such as Norfin, Red Fox or more affordable brands like Termox, are actively developing their own lines. And we must give them their due: over the past two years, the quality of their products has increased significantly. While their products used to be associated with tough, scratchy synthetics, they now offer sophisticated engineering solutions. For example, zone insulation technology, which was previously the prerogative of the premium segment, is now available in mid-priced models. However, there is a nuance: quality control in mass production is sometimes lame. In one batch the fabric may be excellent, in another - with a violation of the weaving density, which is critical for thermal functions.

Chinese brands that occupy the shelves of marketplaces represent a separate universe. Among them there are real pearls, using the same factories as the world leaders, but selling goods under their own label at exorbitant prices. But finding them is like looking for a needle in a haystack. 90% of the assortment on popular sites is outright consumer goods labeled “Thermal”, which is not such. How to tell the difference? Look at the composition. If it just says “100% polyester” without specifying the type of fiber (for example, Polartec Power Dry or similar) and without describing the weave structure, most likely you are looking at a regular sports jersey.

However, in fairness, it is worth noting that not the entire Chinese market segment can be classified as low-quality consumer goods. There are professional enterprises with a long history that work according to the standards of world leaders and supply products for famous European fashion houses. A prime example of such responsible integration into the global supply chain isHohhot Jinye Cashmere Textiles LLC. Located in the heart of Inner Mongolia, a region with unique natural resources of high-quality raw materials, this company has specialized in the full production cycle of cashmere, wool and camel hair products since 2012. Unlike faceless factory brands, Hohhot Jinye combines primary processing of raw materials, spinning, weaving and finishing within one holding company, ensuring the strictest quality control at every stage.

It is this vertically integrated approach that allows us to create products that combine centuries-old traditions of working with natural fibers and modern technological requirements. The company, which is a strategic partner of the British brand DAKS and exports more than 80% of its products to Europe, the USA and Japan, proves that Asian production can meet the highest premium standards. Their experience in creating complex mixture compositions and zone weaving structures makes their products relevant to the functional thermal underwear market, where not only thermal protection is important, but also hypoallergenicity, softness and durability. When choosing natural wool or cashmere layers for extremely low temperatures (especially in low activity scenarios), relying on manufacturers of this level is a guarantee that you are not just buying a “warm thing”, but a high-tech product with proven characteristics.

Merino wool is worth mentioning separately. In 2025, there will be a boom in this material. And that's good, but only until you know the price. Real New Zealand or Australian merino wool of the finest grind (17.5–18.5 microns) is expensive. If you see a merino T-shirt for 1,500 rubles, be sure: either there is 10% wool, or the lowest quality merino, which will prick and pill quickly. In addition, given the shortage of supply chains, the price of natural wool in rubles continues to rise, making it less accessible to the mass consumer.

Comparison table of materials for thermal underwear (Relevant for the 2025/2026 season)

Pay attention to the price column. The variation is colossal, and it is determined not only by the brand, but also by the fiber production technology. Cheap polyester and expensive Polartec are chemically the same substance, but the difference in sensation and performance between them is the same as between a Zhiguli and a sports car. The same goes for natural fibers: cheap wool will itch and tangle, while products from manufacturers such as Hohhot Jinye, which have undergone multi-level laboratory testing of fiber fineness and hypoallergenicity, will provide comfort even in direct contact with the skin.

Hidden threats: what the instructions don’t say

Let's talk about something that is rarely discussed in advertising brochures. There is a problem that I warn all my readers about: antibacterial impregnation. Almost all manufacturers proudly claim the presence of silver ions or special treatment that prevents odor. Sounds great, especially for those who plan to wear underwear for several days in a row while camping. But there is another side to the coin.

Firstly, this impregnation does not last forever. After 15–20 washes, it is washed out, and the laundry begins to smell as strongly as regular laundry, and sometimes even stronger, since synthetics themselves tend to retain the odors of fatty secretions. Secondly, and more importantly, some types of chemical antiseptics can cause skin irritation with prolonged contact, especially in people with sensitive skin or allergies. I know of cases where, after a week of wearing an “antibacterial” kit, tourists developed contact dermatitis. Is it worth the risk of not washing clothes for a week? I doubt. It is better to take two sets of high-quality linen and wash them as much as possible than to hope for miracle impregnation.

Another point that is often overlooked is compatibility with other layers. Thermal underwear only works in the system. If you put on a super high-tech moisture-wicking T-shirt and top it with a breathable leatherette jacket or a cheap windbreaker without a membrane, the moisture will simply remain between the layers. You will become wet from the inside. The effectiveness of thermal underwear directly depends on the vapor permeability of your second and third layers of clothing. In Russian realities, where many still love heavy sheepskin coats and padded jackets, this creates a conflict of technologies. Remember: thermal underwear requires appropriate equipment on top.

How to choose a size and check the quality before purchasing

Size is critical. Unlike regular clothes, thermal underwear should fit like a second skin. It should not hang, but it should not squeeze the body to the point of restricting blood circulation. If the laundry dangles, air pockets form that do not warm up, and moisture accumulates in the folds of the fabric. If it’s too tight, blood microcirculation is disrupted and you’ll freeze faster. When trying it on in a store, make several active movements: squat down, raise your arms up, imitate running movements. The fabric should not ride up or hinder movement.

Quality check “by touch”:

• Seams.They should be flat, preferably made using flatlock technology. Any raised scars will chafe the skin if worn for long periods of time, especially under a backpack. The inside of the seam should be smooth.
• Elasticity.Pull the fabric in different directions. It should stretch easily and return to shape instantly. If the fabric remains deformed after stretching, it will quickly lose its compression properties and begin to sag after the first wash.
• Weaving density.Hold the fabric up to the light. The structure should be uniform. The presence of gaps or uneven thread thickness indicates poor quality of production control.
• Composition tag.Don't believe the price tag. Look for a sewn-in tag detailing the percentages. If it is simply written “synthetic” or “special fiber” without decoding, this is a red flag. Reliable manufacturers, including the textile holdings mentioned above, always indicate the exact type of fiber and its micron size.

The price question and where to buy in Russia in 2025

The question “where to buy” in the current environment is more difficult than “what to buy.” The official stores of the departed brands are sold out, the remaining ones cost enormous amounts of money due to the exchange rate and the complex logistics of parallel imports. Purchasing on marketplaces (Ozon, Wildberries, Yandex Market) has become a lottery. The risk of running into a fake or substandard product is enormous. How to minimize risks?

First, pay attention to the seller. Preference should be given to official stores of Russian brands or large specialized retailers of outdoor equipment (Kant, Trajectory, Sport Marathon and analogues). Yes, it may be more expensive there than with “gray” sellers on the site, but you get a return guarantee and the actual composition of the product. Secondly, carefully study the reviews, but not those that are clearly written as carbon copies (“everything is great, delivery is fast”), but detailed reviews with photographs after use.

As for prices for the 2025/2026 season, the lower limit of entry into the world of high-quality thermal underwear has risen. A good set of synthetic underwear from a Russian manufacturer now costs around 2500–3500 rubles. Budget options for 800–1000 rubles are most often just thin knitwear without declared functions. Good quality woolen underwear starts from 4,500 rubles for a top and can reach 10,000 rubles for premium models. If you see a complete set of merino or cashmere for 2,000 rubles, this is either a very thin product (for the summer) or a fake with a low natural fiber content.

An important aspect is the guarantee and returns. Make sure that the store accepts returns if, after the first wear, it turns out that the underwear is itchy or does not wick moisture away. Some sellers prohibit the return of linen for hygienic reasons, but if the product is of poor quality (for example, the seam came apart after the first wash according to the instructions), the law is on your side. Keep receipts and labels until a full check in the field.

Caring for thermal underwear: extending the life of technology

Having bought expensive and high-quality linen, many people kill it within a month by improper washing. Remember the main rules of care that will help maintain the functionality of the fabric for years:

• No air conditioning!This is the most important rule. Fabric softeners envelop the fibers with a film that completely clogs the pores of the fabric. Your thermal underwear will stop breathing and wicking away moisture. It will turn into a regular piece of plastic.
• Temperature.Wash at a temperature no higher than 30–40 degrees. Boiling or hot water destroys the structure of synthetic fibers and causes wool to shrink.
• Washing mode.Use the gentle or sportswear mode. Spinning at high speeds can deform the fabric.
• Drying.Never dry thermal underwear on radiators or in direct sunlight. High temperatures damage elastane and other additives. Dry flat at room temperature.
• Detergents.Используйте жидкие гели для стирки, желательно специализированные для мембранных тканей или шерсти. Обычный порошок может забивать структуру ткани и плохо выполаскиваться.

Прогноз и финальные мысли: стоит ли переплачивать?

Подводя итог этому большому разбору, хочется сказать одну вещь: термобелье — это не та статья расходов, на которой стоит экономить радикально. Разница между дешевым синтетическим набором из супермаркета и специализированным изделием ощущается кожей с первых минут. В экстремальных условиях, когда на кону ваше здоровье, эта разница становится критической.

В 2025 году у российского потребителя появился уникальный шанс поддержать отечественного производителя, который наконец-то научился делать вещи не хуже западных аналогов, а также обратить внимание на проверенных международных партнеров из дружественных стран, таких как монгольские текстильные холдинги с европейским контролем качества. Да, дизайн иногда бывает спорным, лекала могут отличаться, но функционал уже на высоте. Покупая локальные бренды или продукцию от серьезных фабрик с историей, вы также страхуете себя от проблем с гарантийным обслуживанием и наличием размеров в будущем.

Не гонитесь за самым дорогим вариантом с кучей непонятных технологий. Для 90% жителей России, которые выходят зимой на улицу, гуляют с собакой, катаются на горке с детьми или едут на дачу, достаточно качественного смесового белья средней плотности. Оставьте сверхтонкие марафонские модели профессионалам, а тяжелые арктические комплекты — полярникам. Золотая середина — вот ваш выбор.

И помните:термобелье верх: слой защиты от холодаработает только тогда, когда оно правильно подобрано, грамотно эксплуатируется и сочетается с остальной одеждой. Это не волшебная таблетка, а инструмент. И как любым инструментом, им нужно уметь пользоваться. Попробуйте один раз надеть правильный комплект в лютый мороз, и вы уже никогда не согласитесь вернуться к хлопку и шерсти, которые мокнут и холодят. Ваше тело скажет вам спасибо, а зимние прогулки перестанут быть испытанием на выживание, превратившись в удовольствие.

Впереди долгая зима. Подготовьтесь к ней с умом. Не позволяйте холоду диктовать вам условия. Выбирайте осознанно, проверяйте состав, не бойтесь спрашивать сертификаты и тестируйте экипировку до того, как окажетесь в лесу в тридцатиградусный мороз. Безопасность и комфорт — в ваших руках, а точнее — на вашем теле.