I have lost almost 70 lbs and my body is firm, unlike some of the Biggest Loser participants who have lost their weight in a very short amount of time (60+ lbs in 4 months). When you lose weight at such a speedy rate the body really doesn't have time to catch up and loses muscle tone instead of fat from within causing flabs, sags and loose skin. It is the same as having weight loss surgery.
I lost as I said 70 lbs, but it is fat loss, not muscle loss and I am still firm. My tummy is still firm, not loose, saggy or flabby, my legs and thighs are still firm, also they are not flabby or saggy and my arm as well are firm. If you touch me my body it is firm, not soft or wobbly flow of skin. You can see it in the pic under "Studio".
My pants are so stretched out from being excessively overweight that you can see it in the pic, they fit very lose and are quite wrinkled around the crotched area and as I said, I am firm, nothing is saggy, it is only the stretched out material from the shorts. It took me over 10 months to lose 70 lbs, but I am glad it was done at a pace that I can tell did not cause any flabbiness or sagginess of my skin and I am over age 40. Also take into account that I ate a high protein, low fat, low cal, meaty meal with salad and veggies every night and during the day had my Medifast and of course 64+ oz of water that also helps with my body and to be well hydrated.
I know persons that lost as much weight as me and look thin compared to me. Then I noticed they average about 5'6' and over and since I am only 5'2' tall the weight loss is different since it seems that I carried all my weight around my tummy and it is where you see the most loss - along my stomach and back area. But you must take into account, everyone is different and your body and its mechanism is just as unique as the next person, so weight loss will be different on everyone as if there will be flabs or not. Exercise and build your muscle slowly and it will fill any flabs if it is not too extreme.