Whether youre in the market for a new waterproof jacket, or you simply enjoy taking an interest in the science and technology that enhances your outdoor apparel, chances are youll have heard talk of breathability fairly often. You know that breathability is a good thing, You know that you want your jacket to be breathable. But youre still not 100% sure you know what being breathable actually means!
The Science of Sweating...
To understand what breathability is, and to grasp why you want your jackets, jerseys, and other apparel to be breathable, we need to take a look at the science behind gas movement, and the science of sweating.
Water vapour is a gas. And, as a gas, its constantly trying to mix with other gases so that it disperses more or less equally. Just about all gases do this, and its actually the main reason that breathability is important.
Imagine that the air inside a room is stuffy. You know that opening a window is the best way to deal with this, but why? Since gases are constantly trying to mix, opening the window gives the thick, heavier air inside a chance to meet the cooler, fresher air outside. Once this happens, the two gases can begin to mix with one anotherthe heavier, stuffier air leaves the room and is replaced by the cooler air from outside. The two gases have mixed, and equilibrium is achieved.
Allowing Vapour to Vacate
If we apply this idea to clothing and sweating, the idea of breathability begins to make sense. Your body is constantly giving off heat and moisture, even if youre sitting completely still. Of course, exercising more or wearing thicker clothing increases the amount of heat and moisture being released. This heat and moisture, or sweat, as its otherwise known, rises from the surface of your skin before becoming trapped by the clothing and apparel youre wearing.
As you know, removing thicker clothing helps to cool you down, and can help to prevent a build up of sweat. It can also help to minimise any discomfort caused by wearing sweaty clothing. Unfortunately, removing clothes also leaves you exposed to the elements, and more prone to getting cold, wet, and wind-beaten. Ideally, then, you need clothing that will allow the sweat youre producing to escape, without allowing the elements in.
In other words, you need a garment that can breathe.
The Benefits of Breathability
While breathability is clearly a good thing, it doesnt increase comfort in and of itself. It doesnt prevent sweating, or sweat build-upto stop this, your garments will also need to wick away sweat from your skin. Breathability doesnt actively cool you down eitherwhile some heat will escape, heated air will still remain trapped between your skin and your apparel. Breathability, then, simply allows sweat and water vapour to pass through your garments in order to reach the cooler air outside, where it can quickly move away.
Of course, theres plenty more going on in your technical garments which hasnt been covered here. Next time breathability is listed as a feature, though, youll know precisely what it means.