When the temperature drops, wearing a good set of thermal underwear is like having a hidden superpower to resist the cold. While others stand around shivering, you can stay warm and comfortable with an insulating thermal layer under your clothes. For anyone who wants to spend time outdoors in the colder months, whether it’s for sports, hunting, hiking or working, thermal underwear is essential.
When it comes to choosing a thermal underwear set, it’s important to decide what you will mostly want to wear it for. If it’s for sport or other active pursuits, a fabric that is flexible and allows for a range of movement is desirable. You will also want it to wick away sweat as staying dry will keep you warm and avoid unpleasant clamminess. Here are the thermal underwear sets we’d recommend.
LAPASA Men's Heavyweight Thermal Underwear Long John Set
Fleece-lined for when it's freezing
When the weather is freezing, reach for these heavyweight fleece-lined thermals. As well as retaining heat, the fleece reduces friction on your skin and wicks away moisture so they would work well for snow sports. Four-way stretch fabric with a fit that allows for movement and easily removable tags adds to the comfort factor.
Thermajohn Men's Ultra Soft Thermal Underwear Long Johns Set
Flexible and good for sport
This thermal top and bottom are designed to keep you dry as well as warm thanks to a poly-spandex material that wicks away moisture and controls odor. The fabric is also stretchable and lightweight enough for sport. The bottom has an elastic waistband and a fly and there are no tags to irritate your skin.
Carhartt Men's Force Classic Thermal Base Layer Union Suit
Warm to wear with convenient features
This classic union suit is 60% cotton, 40% polyester for warmth with a snap button front making them easy to get on and off. A waffle knit traps heat and Rugged Flex technology ensure easy movement. Comfort is added by a low stitch waistband, flatlock seams and tagless labels, and convenience comes from the button fly and back flap.
Rocky Thermal Underwear for Men Fleece Lined Long John Set
Comfortable and comes in three weights
Available in three weights – light (55% cotton and 45% polyester), medium (92% polyester and 8% Spandex) or heavy (90% polyester and 10% Spandex) – depending on how much warmth you need, this set insulates you from the elements while wicking away moisture. They have a comfortable fit with a fly front opening, neckline and cuffs.
Bottom line
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The best thermal underwear sets are an essential investment if you want to be outdoors when the temperature drops. While warm outerwear is important, thermal underwear will help you retain heat right next to your body. They are easy to wear under your clothes to keep the cold under control and let you enjoy sports, activities or spectating for longer periods even when it’s freezing out there. We recommend LAPASA Men's Heavyweight Thermal Underwear Long John Set as our pick for most men. You will feel most the benefit from thermals when it’s really cold and this set is fleece-lined and able to cope with lower temperatures while being affordable and well-made.
Everyone should try a classic union suit at least once in their lives. The Carhartt Men's Force Classic Thermal Base Layer Union Suit is a great example and as well as being warm and highly practical will get a smile from anyone who’s seen them worn in countless Westerns.
