There is the common adage 'hard work never killed anyone', but it's always struck me as being silly because it's so obviously not true. History is full of people who were either worked to death (as slaves or in gulags or prison camps), or who just had shorter lifespans because they were "low status" workers who had a life of hard labour. In almost every society, the people at the top with leisurely lives live longer than those who do hard manual work.
Though then there are those guys who keel over dead after playing computer games for days on end - not really sure where they fit in. But then, I suppose 'work' is not a perfectly-defined concept either. I mean, what does it actually mean other than 'something you wouldn't do if you didn't have to in order to get something else you want''?