Couch Potato

Is there a certain amount of time you have to be on a couch watching TV and eating snacks to be called a Couch Potato?  I am trying to put my finger on what the requirements are to be a Couch Potato.  I wonder if animals can be a couch potato...  How about kids...  I am figuring you have to be a certain age.  The kids who watch cartoons are not included.  Couch Potato is such a generic term.  Mr. Couch Potato or Miss Couch Potato sounds like a nice name too.  What if you are not sitting on a couch and instead you are sitting on a chair watching TV and eating chips.  Are you a Chair Potato?  What about the people who watch from their bed. Are they a Bed Potato?  There are lots of things to think about when it comes to being a Couch Potato.