I know a few people who spend hours doing intensive work a day (PhD program for one, medical school for another), and don't want to become involved in more inte

I know a few people who spend hours doing intensive work a day (PhD program for one, medical school for another), and don't want to become involved in more intensive hobbies (e.g. literature study, art films). The deeper pursuits are left for the career, and hobbies are an easy way to get your mind off it during rest periods.