That true too, muscle weighs a lot, it was amazing when I worked with dancers - who are near 100% muscle, you think they weight 90 lbs soaking wet, but when you go to pick them up - in the literal sense, on the way to doing it in the metaphysical sense - they have a solid 20 lbs over that.
But bone size and density has something to with it too, as you don't want to lose bone density, that's bad. There is more to weight then height.
