TubeNet

If you practice like this:

https://www.youtube.com/watch?v=aV1oU0FGOqo" target="_blank

I definitely get warmer when I play, take off sweaters etc. Whether I burn calories is inconsequential given my weight of about 100#. I might have to have an extra ice cream once in a while. But I'm allergic to alcohol and love beer but can't drink it.
And my blood pressure is generally about 102 over 60, so I guess I'm atypical for a tuba player. But you knew that....

It's very hard to play with a suit coat on anymore, these Symphony Orchestra guys must be in perfect shape to wear their coats for hours on stage.

I have definitely worn Under Armour beneath my suit before.

I have to start losing layers when I'm playing a contrabass or else I'll start sweating. Bass tuba doesn't seem to do the same thing to me, though....