For a very non-active person, I seem to participate in a lot of physical activity these days - as you grow older you really can't ignore your lack of fitness as it actually stops you doing stuff you like! Add to that a couple auto-immune diseases and ... well ...
So, here I am a person who fits life around an "exercise" schedule, albeit a sedate one! An ideal week sees me doing two water aerobic classes and one yoga class (this will hopefully be joined by a second next year). And it is probably in the water that I occasionally have moments I could describe as fitting today's prompt.
I am pretty good of getting one with thinking while my body does the workout - I know that isn't the general idea - but every now and then I find myself 100% focused on the movement my body is doing and just feel the whole experience. Where my brain disconnects from thinking and just tunes into what is happening.
Maybe this is the "zone" real athletes refer to? Usually it is just a fleeting moment before I get back to thinking about what I need to get at the shops on the way home!
BTW, In both my water aerobics classes, I am the "baby" of the group! There is a lot to be said for working out with women who have ten - twenty years on you!