How do you know if you have gained muscle or fat? I've gained a couple of pounds since December but I specifically notice it in my thighs. My jeans are tight in the thighs and it's hard to find ones that fit (the waist will be too big but it will fit in the legs, I need Clydesdale leg jeans lol). The only thing I can think that I've changed in my routine is adding some of the Low Impact series DVDs. I've been trying to eat better and still running, cycling, weights and of course, your dvd's, but the scale isn't moving. My legs are very muscular to begin with and everyone is saying it's muscle and not fat. What can I do to go back to my old size?