Effects of whirlpools on workouts?

Got a gym membership to a place that has a nice whirlpool/hot tub/whatever they’re called. I was wondering what the physiological effects would be on using it before and after workouts.

I’ve been spending 10 minutes in it after workouts to relax - and I find myself extremely weak when I get out - completely drained. I don’t know if that’s positive, negative, or either.

I’ve considered spending 5-10 minutes beforehand too to loosen up, but I don’t know if that would have benefits or not.

What are the general physiological effects, and what are they specifically pertaining to excercise? Are there benefits, or negatives?

That wouldn’t work. You’ll get your body temperature raised slightly, but none of the other, more important effects of a warmup.

I wouldn’t do it instead of warming up, but in addition to.

I thought I’d read somewhere that a high external temperature causes increased bloodflow among other things - that seems like it would be beneficial, if so.