just like 90% of men will develop really good pecs and backs by just doing some push ups and pulls ups (sadly i'm the 10% and was being made fun of and up til this day strangers walk up to me and say "nice arms! but why don't you train your chest?"), 90% of women will develop great quads, hams, calves and glutes by simple training (even body weight squats and lunges will do the trick)... couple that training with an anabolics diet (lots of beef and rice and tasty food), and they'll develop a lower body that would make any man's mouth water (except if you're a GBer, it'll make you vomit from how fat they are cuz you're gonna look for a girl with stick legs as if she was a 12 year old boy soccer player)
the reason most american girls have shitty skinny legs if they train is because they eat 10 calories per month... very apparent from their rib cage sticking out... those are the thin ones... like... what? 2% of america? LOL
I know a girl who quit training after 3 weeks because her trainer was having her do squats every day... she said her thighs and ass were swelling and she hated how she looked (the kind of woman the believes the magazines when they say "there's nothing sexier than having your legs look like sticks and ass looking like an extension of your back with a line in it")... god damned idiots...