[aaron5]

I've found this for myself, too, seemingly.

And it helps to have "work" that is hard but enjoyable. Then when you're working hard, you're looking forward to rest; and when you're resting, you're looking forward to work. And you throw in a lot of "play" too, if possible (for me, sport, relationships, etc.). So, whatever you're doing, you're enjoying what you're doing AND you're looking forward to something (work, rest, or play), which adds enjoyment to the present (work, rest, or play).

My anecdotal data-point.