Reflections on Past, Present and Future

I do my cycle on an exercise bike these days, but I get something similar when I go swimming. The difference is, when you pass or get passed by someone running or cycling, they're generally gone. When you're swimming, you're going to come by them again sooner or later. You can get some surprisingly even match ups between weaker swimmers who just sprint for a lap and then rest, and the endurance types who just power on and on.