The Elliptical machine....something I've been using for almost a year now,but now more into it, say 3x a week. I know its a cardio workout but also all body. However I noticed my thighs (Quads, hamstrings) get the most out of it. They got a lil bigger an very solid. along with the soreness that gets contributed as minutes go by. I have gained weight but dont see much change where. except this area mentioned and my gluteus maximus (ass) and the normal fluctuation of my not soo fatty but flabby on occasion Stomach. I'm not complaining but just want your input.