I used to until I realized that catabolism just occurs in minute amounts. You don't lose pounds of muscle overnight. If your body isn't well, you can drop some intramuscular water and that's it. What's the problem with that? Just get better, have a couple good workouts and fill back out. That's all. If you lose micrograms of amino acids and muscle tissue it's impossible to notice. Absolutely no point in worrying about shit like that. Worrying in and of itself is probably more catabolic than anything.
Another thing I did was built a solid foundation. Had to come off gear for a long time which exposed my crappy foundation. It's probably better than what I give it credit for, but coming off and feeling like shit really does something to you. I focused on getting healthy first, building my cardio and then slowly building muscle (which is slow as fuck being clean/natural). Looked very good without drugs and looked even better on them once I started juicing again. Don't have to juice hard or diet as hard now. I have a base. If I get smaller, I'm not a small guy, I'm just smaller than what I'd like. I have a base. So no more fears of being "small". Fat guys feel small because they usually are small and look like shit to begin with; their only saving grace is being huge and fat so they feel "big".