I can see and feel muscles on my legs, arms, shoulders, butt, and torso that just weren't there at all before, and I estimate the total based on knowing what 1/2 pound raw hamburgers look like. I know, it's a guess, but I'm positive it's more than 2 pounds of muscle I've gained over the past 4 months. Also, I might stay the same weight for a month, but my pants get looser and I see the fat lumps on my hips slowly melting away, so I know I'm losing fat. If I'm losing pounds of fat but not losing weight and seeing my muscles getting bigger at the same time, I must surely be gaining muscle weight, no?