As a courtesy, these two express a similar sentiment. But there is a shade of difference in the meanings, which I will illustrate with different words and analogous construction (because I think it becomes clearer with specific short term activities and physical effects). If I say "It is tiring to run", I indicate the activity and its effect happen at the same time, i.e. whenever I run, I get tired. If I say "It is tiring to be running", I am talking about an activity that is in progress at the time in question, which is now, and I'm saying I am tired now. Perhaps other times when I go running -- it's cooler, say -- I might not get tired so easily. It's the same in principle with "working", except you're probably talking about a continuing uninterrupted relationship that is in place at the present, so the distinction isn't as apparent.

Both of them are ways of saying the same thing. 2-, I believe, is more formal.