I realize that a good portion of the country is covered in snow, including places I've formally lived like Boston and upstate New York. Yet, it seemed like a good time to talk about...sweat, specifically sweat glands. Nothing says a good winter read like talking about sweat glands, right?
We have two different types of sweat glands: eccrine glands and apocrine glands.
Eccrine glands are found all over the body and are our body's primary cooling mechanism. When your body gets overheated, whether from vigorous movement, a hot yoga class, or warm weather, those glands secrete a compound of water/sodium chloride on the skin. The fancy name for this process is thermoregulation.
The apocrine glands, however, are just located in a few areas of the body, including the armpits, groin, and scalp, for starters, and these are our "smelly sweat" areas. (That's a very technical term for the secretion of sialomucin, or sialic acid. Don't ask me any chemistry questions...it's definitely not my field of expertise!) These glands are more sensitive to adrenaline and rather than secreting odorless water/sodium chloride, instead secrete a combination of proteins, lipids, water, sodium chloride, and gain their odor upon contact with bacteria which "eat" the molecules, causing a change in odor. This type of sweating is a direct response to stress, whether that be public speaking, anxiety, performance, auditions, etc.
Now a good question would be, why do I care about this when I'm freezing in 5 feet of snow?
Well, the apocrine glands are a part of our fight/flight autonomic nervous system response, and are affected during performances, auditions, etc., which you know from experience. We've probably all experienced the anxiety perspiration phenomenon, whether in publicly speaking, performing, or auditioning. More importantly, beta-blockers affect aprocrine production by decreasing the overall stress response on the body. If someone has hyperhidrosis, or excessive sweating, beta-blockers can be prescribed to treat that (assuming they don't have asthma or blood vessel issues). While the chemical binding process is a bit more complicated than I can certainly explain, your stage fright symptoms are a big part of the way your body responds to adrenaline, which affects your apocrine sweat glands, which can affect your ability to play your instrument. Obviously excess perspiration is a big problem, especially when handling an instrument, especially a string instrument.
So here's the second part: how often have you heard the slogan "Sweat out your toxins with hot yoga/saunas/hot tubs, etc?" When people talk in fitness land about hot yoga and sweating out toxins, that's not how it works. Sweating and moving has benefits- removing toxins just isn't one of them. As I mentioned above, perspiration isn't composed of toxins- if it's secreted by your eccrine glands, it's a combination of water and sodium. You don't have 6 beers on a friday night and then at Saturday morning bikram, sweat it all out through your pores. That doesn't mean that sweating isn't good for you or that a post-alcohol sweat fest won't be smelly, but really, your kidneys' and liver's job is handling toxins. So drink water (lots of it!), especially if you're going to be sweating, and know that your kidneys and liver will be handling the aftermath of your alcohol/junk food/sugar choices, not your sweat glands.