Not Cathe, but a reply I read in a fitness book at one point was that to lose fat you must reduce cals. While reducing cals it's is very unlikely you'll gain any muscle mass as the requires excess calories. To maintain muscle during a calorie restriction, it is best to increase your protein ratio and continue to lift heavy so as not to lose any muscle gains. Who knows if that's the way to go, just something I read and thought I'd pass along.