As a former competetive swimmer and a current biology teacher I can say that swimming and running made me equally "hungry". The one thing that swimming does is pull huge amounts of water out of the body, moreso than running. In addition to sweating during the workout (yes swimmers sweat), the chemical composition of the pool water also strips water from the body through osmosis. That is one of the reasons your fingers and toes get pruny and wrinkly looking after a long bath, swim, etc. For me a huge glass of water after a workout goes a long way to helping snub that hunger. Many times the body will read thirst as hunger pangs. Since many LC programs are naturally diuretic as well, a quick dip for some excercise will further dehydrate an athlete. Just my own opinion, a post workout meal with lots of fiber also helps to ease hunger and keep me from feeling hungry again before bed. I supplement my LC diet with extra fiber to make sure I am in the 20-30 g range every day. I don't know if this answers the question but I hope it helps provide some personal insight.

Happy LCing!
Katie