As far as Samus' Height and Weight are concerned, it appears that those numbers that I used only appeared in the Metroid II manual and the NP Player's Guide for Super Metroid, and have not been seen since, so they might have been retconned, or were just made up like Sir_Stabbalot mentioned and are no longer canonical.
Their is also a difference between looking muscular and having muscle; if I remember correctly, someone can look more muscular if they dehydrate themselves, which means that looking muscular does not equal being healthy nor is it the true measure of someone's muscular makeup.