You're skiing down a mountain.
You reach the bottom in a light sweat and you feel it.
The wet, clammy, feeling beneath your ski pants.
You bought the wrong underwear.
Those 100% cotton long johns are trapping all the moisture in.
The perfect pair of thermals will keep you warm while wicking away sweat.
Layering is the simplest way to protect your body from extreme cold weather. The base layer is the one closest to your body. Pay attention to it and you will have nothing to worry about.
The advantages of picking the right base layer?
- Comfort, without sacrificing the sex appeal of your clothing.
- Increased freedom of movement for outdoor activities.
- Can be worn in layers – which improves the insulation of the clothing. More air is trapped using several thin layers than by a bulky single layer.
- Potential energy savings at home as you won't need to turn the thermostat up to stay warm.
When you buy thermal underwear, you want performance, durability and comfort under any conditions. You don't want to skimp on it.
This article is going to cover exactly what to look for when buying thermal underwear.
This educational article is brought to you by Tani USA. Living in Wisconsin, temperatures drop below freezing several times a year. I personally own and trust Tani's high-quality thermal underwear to keep me warm during the winter seasons.
The perfect fit will support but not constrict.
Thermal underwear functions as a second skin – creating an insulating layer between your body and the fabric.
For warm conditions – your underwear needs to be loose. In cold weather, snug-fitting underwear traps the heat generated by your body and boosts comfort.
If a garment is advertised as athletic fit, expect it to be snug.
If it fits poorly – the underwear is likely to create hot pockets instead of distributing warmth event, making you feel some discomfort. Form-fitting underwear avoids this predicament allowing you to comfortably wear layers over it.
Form-fitting underwear avoids this predicament allowing you to comfortably wear layers over it.
Choose a garment with a slick outer surface so that your other clothing doesn't get stuck on it.
There are two components to picking the right fabric – weight and material.
Thermal Underwear Fabric Weight
Each fabric weight offers different advantages. Here are some general guidelines for picking the right weight for your base layer:
- Ultralightweight: Also called micro weight, suitable for mild to cool conditions.
- Lightweight: Preferable for cool to moderately cold weather and for a high level of aerobic activity.
- Midweight: Suitable for moderately cold to cold weather. Midweight fabrics are the most versatile and can be worn for a variety of recreational and sports activities.
- Heavyweight: Suitable for extreme cold and frigid temperatures when more warmth is required to regulate the body temperature. Heavier fabrics are suitable for winter sports in the snow.
Common Fabric Materials For Thermal Underwear
The material of your thermal underwear needs to be luxuriously soft and yet extraordinarily resilient to keep up with whatever weather conditions you experience.
- Synthetic Thermal Underwear Fabric – Made especially for extreme cold conditions, synthetic fabrics are the best for thermal underwear. Polyester, spandex, lycra, and nylon are often combined with other natural fibers to provide the right amount of moisture wicking properties and heat retention required.
- Wool Thermal Underwear Fabric – Natural fiber merino wool cleverly balances your body temperature and provides great moisture management, no matter what the conditions.
- Silk Thermal Underwear Fabric – Silk is a lightweight option for activities in moderately cool weather. Wear it for recreational snowsports and indoor lounging. Silk provides a luxuriously soft texture without adding bulk. The drawback with this fabric is that it transports moisture away from the body more slowly.
- Cotton Thermal Underwear Fabric – Unlike merino wool, synthetic fabrics or silk, cotton retains perspiration. It leaves you feeling chilled, wet and clammy. Despite the affordable pricing, cotton is the least preferred option for thermal underwear comfort.
The warmth to weight ratio of synthetic fabrics like acrylic and polyester are 3-8 times higher than knitted or woven fabrics like wool or cotton.
Click Here To Download Antonio's Top 10 Thermal Underwear Rankings
#3 Thermal Underwear Function
What is your main purpose in buying thermal underwear?
Do you need it for everyday use to provide warmth, or to facilitate freedom of movement during physical activity, or to conserve body heat in frigid temperatures?
- Warmth – Thermal underwear regulates your body temperature, keeping you warm and dry. The weight of the fabric determines the level of warmth provided by the underwear.
- Stretch – Cotton tends to be restrictive in its tendency to stretch uniformly. Something with a 4-way stretch. Cotton fails. Wool has some stretching properties.
- Bacteria Resistance – When you can't shower daily, bacteria resistance is imperative.
- Loft – Low-density weaves in the fabric ensure that the garment keeps its shape while trapping air between the layers. Fabrics with good loft keep your body heat with the least amount of space and the most amount of flexibility. They insulating body heat and prevent the cold from reaching your body.
- Moisture Wicking – Moisture wicking is important when selecting thermal underwear because the purpose of wearing thermal underwear is to stay warm and to stay warm – you have to stay dry.
The thermal-preserving property of a base layer drastically reduces when wet – either through external moisture or through sweat. The body tends to lose heat quicker during the rest phase following physical activity and the wet base layer brings the body temperature even lower, resulting in hypothermia or even worse, death.
A base layer for cold climate could be anything from t-shirts to briefs, to long-sleeved tops and full-length bottoms.
However, there are only two styles of thermal underwear:
- One piece thermal underwear suit.
- Two pieces bought separately or as a set which includes a long-sleeved top and a lower body piece covering the waist to the ankles.
Both kinds can be very close fitting and contoured to fit your body or they can be looser fitting.
It all depends on the type of fabric e.g. with a cotton blend, the thermal underwear is likely to be looser fitting whereas the microfibers are more form fitting and tend to keep their shape better than the cotton types.
#5 Thermal Underwear Care
Read the manufacturer's note for specific care instructions. To get the most out of your winter thermal underwear, pay attention to these guidelines:
- Cotton – Wash in cold water to prevent the fabric from shrinking. Cotton takes longer to dry. Allow it to air-dry for best results. For faster results, lay the garment flat on a towel. Avoid hanging them up as the fabric starts to stretch over time and lose its shape.
- Silk – For silk thermal underwear, hand-wash or use the delicates option on the washing machine.
- Wool – The requirements to wash wool are similar to those of cotton fabrics. Was in cold water and dry on a towel for faster results.
- Synthetic Fabrics – These fabrics are easy to care for and dry quickly. For best results, wash them inside out. It is safe to wash them with warm water. They are dryer-safe and maintain the original shape even ig they are hung out to dry.
This educational article is brought to you by Tani USA. Living in Wisconsin, temperatures drop to below freezing several times during the winter. I personally own and trust Tani's high-quality thermal underwear to keep me warm during the winter seasons.