Base Layers 101 - Thermals & Long Johns

Base Layers 101 - Thermals & Long Johns

When braving the great outdoors, it’s essential to always consider and plan for personal safety. When recreating outside—whether you’re hunting, fishing, or camping—you’re at the mercy of nature. And in the environment, the elements can be unpredictable. We’ve all heard stories of weather patterns changing unexpectedly, stranding hikers in harsh conditions. So planning is critical. 

Believe it or not, one of your best defenses against harsh weather conditions is a good, old-fashioned pair of long johns. Nowadays, you can call them thermals or thermal layers, and the long-sleeved tees and pants have come a long way since your grandpa’s pair.

What Is a Base Layer?

Firstly, what exactly are thermals and long johns? Both fall into the category of base layers, which are layers of thin clothing—such as long-sleeved tees or bottoms—worn against the skin and under other clothes. They act as a warm base and a layer of insulation against harsh conditions like cold temperatures, rain, wind, and snow. They are exclusively used for when you are recreating in the outdoors, such as hiking, during colder temperatures. 

The Difference Between Long Johns and Thermals

When preparing for time spent in the outdoors, long johns and thermals aren’t that different. But, language-wise, they are not the same. “Long Johns” is a slang term for long underwear, which is usually (but not always) made from cotton and are just as they sound—an extended version of underwear. With long-sleeved tees and pants down to the ankles, they cover the entire body. “Thermals,” on the other hand, is shortened from “thermal underwear.” Although it looks and acts the same as long johns, thermal tees usually contain wool.  

But in the outside world, the terms are interchangeable, with the most significant difference in the material. When spending time outside in the cold, especially when sleeping, it’s better to use long underwear made from wool. Wool is a moisture-wicking material, meaning that it keeps your skin dry. When your skin gets wet from sweat or humidity, then it can become cold. But wool keeps moisture off your skin, and therefore, keeps you warmer. 

What to Buy

If you’re going to be outside in the cold, such as with camping or hunting, it’s best to bring along thermal tees and bottom layers. But if it’s summertime and the temperature isn’t expected to drop too low, you can opt for cotton layers. Just remember that wool is best for moisture-wicking, and cotton is best for sitting or sleeping at relatively warm and dry temperatures.

How to Wear Base Layers

Wearing base layers is relatively simple. Since it works as a base to keep the body warm and insulate from the cold, it sits at the bottom of your clothing. It’s the first thing you put on. Next, you can continue with another thin, wool-based layer, then something like a puffy jacket to hold in the heat. Finish the layers with a shell that’s resistant to wind and rain for the perfect combo to keep safe and warm while outside.