Now that winter is approaching, it’s time to start thinking about some really warm clothing. Warm clothing is not just about comfort – in some cases it can be about safety, and in some cases it can be about saving energy (and therefore money!).

Thermal underwear can be a fantastic way to meet all of these criteria. If you have never worn thermal underwear before, then you don’t know what you’re missing. If you are imagining something which is itchy and uncomfortable, like the long johns your grandfather might have worn, then you are in for a surprise. Modern thermals are smooth, sleek, and very comfortable.

So who wears thermal underwear? The answer is probably a lot more people than you ever thought. Professional athletes, members of the armed forces, and adventurers are just a few examples of people who wear thermals all day every day. Thermal underwear can prevent you from sustaining injuries (especially for athletes who don’t want their muscles to cool down) and can serve as a bit of insurance policy in case you get stuck in an unfortunate situation. It is important to note as well that thermals will not necessarily make you overheat when the weather gets warmer. In fact, if you start sweating in thermal underwear, the fabric will actually cool you down again.

This works through the principle of capillary action, and then of evaporation. As you sweat, the fibres of the thermal underwear draw the moisture away from your body. The warmth from your body then causes that liquid to evaporate out of the fabric. As this occurs, energy is carried away with the evaporated sweat – this results in you cooling down again.

You can get cotton thermal underwear, acrylic, and even silk and wool. Acrylic fibres are generally the cheapest, whilst silk is the most expensive. Cotton can represent a good budget choice, you need to be careful with his fiber. Cotton loses its insulating ability when it gets wet, and as such is not suitable for serious survival and adventure situations.

Keep in mind that a pair of thermals, complete with some nice thermal gloves would make excellent gift for the keen adventurer, and with Christmas approaching what better present would there be!