Norbert Weiner famously hiked for hours.  And swam, belly up, with a lit cigar in his mouth.

Albert Einstein took a violin with him everywhere he went, and played every day.

Here's an Einstein reminiscence:

I sometimes ask myself, how did it come that I was the one to develop the Theory of Relativity?  The reason, I think, is that a normal adult never stops to think about problems of space and time.  These are things which he has thought of as a child.  But my intellectual development was retarded, as a result of which I began to wonder about space and time only when I had already grown up.  Naturally, I could go deeper into the problem than a child....