Yeah, where I went wrong in particular was in misremembering the relationship with contractility. I thought a beta blocker was a positive inotrope, not a negative one. But I also have pretty atrocious memory and recall, so I figured I was missing something, somewhere.

Okay, thanks for the clarification; I know it's used in musical performance, so I could've followed that case back to its correct line of explanation if I'd thought about it. And that's really interesting about the precision sports - I wouldn't have thought of the advantage of a beta blocker in sports like that but it makes perfect sense.

For some reason, I could never keep the adrenergic receptors straight. I think part of the difficulty for me, personally, is that I've taken a beta blocker and felt like it was easier to "breathe" which is obviously nonsensical from a bronchiole standpoint, so I probably keep transposing the effect in my head to make sense of that.

Thanks for the chance to revisit some of this!

Dumb question, based largely on what is probably an over-simplified understanding of cardiac output. I thought beta blockers improved cardiac output?

I always thought of it more in terms of the contractility improvement than anything, although I know a beta blocker alters other things included in CO, but with that basis of understanding in mind, maybe I'm missing the fact that some other factor outweighs the contractility thing?