I would echo what others have said and add that, based on what you've written, I would wager that you've got one heck of a lot of inflammation going on all over your body! When body cells are inflamed, they hold onto excess WATER. Water weighs 8 pounds per gallon and you would be amazed at just how much excess water you can have "hiding" in those inflamed cells.

I recently got into a bad patch of chiggers and ended up with chigger welts all over my body. All of my clothing still fit just fine and I certainly didn't look like I'd gained an ounce. But the chigger welts added 3 pounds! Seriously, the chigger welts added 3/4 of a QUART of water weight! Soon as they subsided, the excess weight went too.

With all your running, you could easily be carrying quarts of excess water spread in tiny amounts all over your body. Take a few days OFF from running and give your poor muscle cells time to recuperate and see what happens with your weight.

And PLEASE, stop with the starvation diet before you totally screw up your metabolism! You want to find a Way of Eating (WOE) that allows you to lose weight slowly and safely AND, more importantly, a WOE that you can stick with for life so that, once you get down to your goal weight, you never regain!

Do you honestly think you can possibly continue to eat only 500 to 800 calories a day for the rest of your life???? No way! But if you force your body to survive on only 500 to 800 calories for a long enough period, then as soon as you start eating anything approaching a normal amount again, the weight is going to pile back on....and the next time you try to lose weight, you may have to drop to 250 to 400 calories per day to do it.

That is madness! Stop torturing yourself.

A proper low carb diet should be a pleasure that you can and will want to stick with for life!