Being a volunteer dept, we have none. We have basic requirements to ride without waiting for an officer's permission, but no physical requirements. They say too many people would quit if something like that was instituted. I think that a rule like that would scare off the dead weight and leave the people who really want to be there.
There are people who want to fight the fire and then there are people who want to be at the fire. I'd rather ride with 3 other motivated people than 6 other people who not motivated.