Hum, I believe when you are super fat you have a lot of fat cells .. they are numerous and they are big ... so when you lose weight, you lose the fat of course, the fat cells "shrink" but they are still there waiting to get bigger again as soon as you start being naughty : not exercising, procrastinating, eating bad food in front of the tv, etc.
That's why it's easy to put the weight back on, especially if you lose the weight very fast (as they do on THE BIGGEST LOSER Tv show for example, when you see how many of the contestants have now gained a lot of weight back.)
The fat cells are numerous so it's easier for them to keep the fat on the body. That's why you have to find a permanent solution, something you can stick with for life ... if you stop following your habits once you are done losing weight you will put the weight back on and maybe even gain more weight ... so it's important to eat well and exercise too, I'd say 4-5 times a week is pretty good, at least 20 vigorous minutes each time, more is better but that's a minimum. Unless you have a monastic lifestyle of course, eating healthy, watching your calories, then you can cut down on the exercise, but few people do that ...
Cheers !
Marc
37 Years Old, 5'10" Tall
Nov. 1st. 2008 : 280 Pounds
Nov. 1st. 2009 : 190 Pounds
(1 Year : - 90 Pounds)
Current Weight : 191 Pounds