How exactly do nerves communicate with muscles?


They don’t have eyeballs and ears,and relevant brain cortices, obviously, so how do they talk? Is it just a simple In:Out/On⋮Off system?

I was thinking about the trick of flexing the thigh muscles if you need to pee, to redirect blood away from the bladder, And trying to figure out why else it works, regarding the work between nerves, muscles, and ultimately the circulatory system.

In: Biology

Nerves send an electric pulse to the muscles, and the muscles respond to it by contracting, causing movement. It’s not an electric current as such, more like a complicated electrochemical process, but electricity is definitely involved. That’s why if a person gets electrocuted by holding some electrified metal bar for example, all their muscles contract and they can’t let go of the bar.