I swim laps for at least one hour once a week and look forward to it every single week. That makes it a great exercise right off the bat.
I feel I'm losing the fat from my other exercise (stationary bike, walking, and hiking), but getting my figure from the swimming. My fat arms are toning up nicely and until recently I did no weight work at all so I know it's from pulling this body through the water.
But I do have to plan for the after hunger. I still remember the mistake I made doing my grocery shopping after 85 minutes of laps. Ended up eating my calories back in the car on the way home (couldn't even wait to get home). Won't make that mistake again!