If you've bought long johns in the past, you may have heard that they will keep you warmer by themselves. However, your base layer of thermals is meant to keep you warm by themselves. Before you start the screen and shock, consider this, long johns are intended to retain your body heat. This is considerably better than being naked. It's also better than say if you would wear only t-shirts. But the thing is, your base layer of long johns is meant to prevent you from getting cold.
While some may argue the semantics, the primary purpose of your base layer is to prevent you from getting too cold while you are outside in the winter weather. They don't keep you warm, they keep your body heat from escaping. Knowing this, are long johns warm?
While there are numerous blogs about which thermal underwear is going to be the warmest, all of them will do pretty much the same thing. One of the most important questions you may be asking about thermals is which one is going to keep you warm the longest.
For your thermal underwear to keep you warm, you were going to have to be active. This can mean walking around your home, going for a jog outside, or even working in a cold office environment. This is because long john works by relying on the body heat that you produce. While they do not keep you warm on their own, they keep you warm by distributing body heat across your skin, which keeps you warm.
This is how your long underwear works as insulation. If you are standing still, you still have body heat, but your thermals are working on something called conduction. As you move, even if it's a slow walk, your body temperature is going to rise. Your thermals will keep you warm by trapping that body heat on your skin and preventing it from escaping through the fabric.
I will also look away from any moisture like your sweat. That way, you don't have any of that wet clammy feeling as you move. Thermos will help keep you warm by also keeping you dry. Thermos does this by facilitating the evaporation of your sweat from your skin and releasing it through the breathable fabric itself. Between the retention of your body heat and the moisture-wicking, thermals prevent you from getting cold. Others will say that when they do this, they work at keeping you warm.
No matter which side of the semantic argument you follow, owning more than one pair of thermal underwear will be important when it comes to it. It will also prevent you from doing too much laundry because over washing can break down the fabric. Keep in mind that while you can wear your thermals independently, they are best worn as a base layer in the layering system.
