That number on a scale

This has been a thing that's bothered me for a while. It's partially spurred by someone I know. This person is obsessed with making that number on the scale go down. She goes running, because "it's a good way to lose weight!" Yet when she complains about not being able to go running (which is a lot, and usually the reason is the weather "Oh, I don't want to go running when it's hot"), and I suggest that she do some weight lifting, she gives me a look of disgust and goes, "I want to lose weight, not gain it." Like I told her to become fat. That's not the case.

What is the stigma against girls having muscle? When did society become so obsessed with a scale? It makes me frustrated that people look at me funny when I go do weights. It frustrates me that girls are in a race to see who can lose the most weight and be skinny and good-looking. There's a stigma against being big- fat, muscular, anything that's not in the magazines- that girls will criticize other girls who aren't trying to actively become or remain small.