I get the point of warming up before exercise. It’s pretty much the same as a car: parts tend to be more brittle when cold so warming it up means you have less chance of damaging things etc.
But why does the body need to cool down slowly after a workout? My car doesn’t need to cool down after a race: I just switch it off.
I mean I know that the heart is still pumping fast so blood can pool and you can faint etc if you don’t cool down, but if the heart just returned immediately to resting pulse after the effort, blood wouldn’t pool.
If an answer is that muscles still require more blood after a workout than during their rest state, then the question becomes why do muscles still need more blood after the workout is finished? To wash away waste products? Why doesn’t the body just remove them immediately?
Why does my body need a cool down after a race, but my car doesn’t?