Virus transmit through humidity?

It can be but highly unlikely. It is new so nothing is known which is what is so horrifying. It could go away in a few weeks after the incubation period or it could expand and all of could know people with it and know people who have died from it. It could fade come summer or it could spread where millions have died by August. 

This is what makes this the most horrifying event in history since the Black Plague. This is far worse then the Spanish Flu though possibly it will go away before millions of Americans die from it. We can only hope. 

from what I've read--the coronavirus doesn't like humidity so much--but I would fear that someone will be coughing--or some unknowing infected person with poor hygiene would infect the machines.

As far as we know, this virus is not spread through the air. That would include humidity. Sweat ... well, if you are touching something they touched and if they are contagious, that could be a problem. And they are finding that some people are contagious but have no symptoms.

Coronavirus is spread through droplets released by coughing or sneezing, or by someone touching something that droplets have fallen on (they were saying the virus could last on an item for 2-3 hours, but now they are saying 2-3 days .... we just don't know much about it).

As soon as your area starts to experience community transmission (people who have NOT gotten it from travelling), that is when you stop going anywhere that is not absolutely necessary. You will stop going to the gym.

As far as known, it's through breathing in the germs or touching some infected equipment or door handle, then touching your face, and also through eating or drinking infected food or drink.