I swim five times a week, now up to 40-50 lengths of a 25 metre pool. I am not sure if it helps with weight loss, but something is (could it be the magic packets?) and I certainly feel well, in fact better than ever and better than 50 pounds ago.
I take it a day at a time. Not sure its worth worrying about the weight of muscle versus fat or anything else. Exercise makes me feel good. I hope this helps.
GSQ