Toning and tightening without losing weight?

Hi all! I am on a mission to look better in a bikini and really need to tone and tighten! But I have a big problem! I have gastroparesis, a stomach condition which severely limits my diet and makes every meal a battle not to get sick. I cannot have complex carbs like whole grains, anything wheat, etc. I also cannot eat raw vegetables or cooked vegetables with peels. The perfect diet for my condition means things like soup, smoothies, mashed potatoes, white bread...anything soft and easy to digest, AKA high in processed carbs. As you can imagine, I've lost weight but have the skinny + fat look going on. I'm thin, but I've lost muscle! I really want to tighten up again, but I know it's going to take a lot of work and careful consideration as to my diet. I'm just wondering if anyone has any advice as to how I can exercise and build muscle. It's really hard for me to consume a lot of calories because meals are so hard and I can't eat much at one sitting, but I don't want to exercise a lot without eating much and end up lose more muscle instead of building it. At the same time, I know I need a calorie deficit to burn fat! It's all so confusing!!!

http://caloriecount.about.com/forums/fitness/ toning-bad-word-only-people-use

What you want to do is actually weight lift - lift heavy - lift 3 times a week - do squats, deadlifts, push ups, rows

Get a good program - starting Strength - New Rules of LIfting, Female Body Breakthrough and lift HEAVY

To get nice sculpted muscles you got to use them.  For core do planks and mountain climbers and squats, and presses and rows.

Use protein powder in your smoothies- add it to your soups, potatoes and what not.

I actually eat gluten-free and I find my body is so much a happier.  You may want to look at protein powders to get the added protein in your diet. Optimum Nutrition has a natural line, which has only a few ingredients. Your system may be able to tolerate it better. I also use "Egg Whites International 100% Liquid Egg Whites" in my drinks.  Also, eat every 3 hours so your body is not going into starvation mode and feeding on your muscles.

As the above posted stated... weights weights weights and lift as heavy as you can to where you're struggling on your last repetition in your last set.  Don't work on the same muscle for 48 hours. Your muscles need rest too.