I notice this more and more. Not so much at my gym, since I rarely go to anything other than the 5:30 AM boot camp, but around town, there's this sub set of 35-50 y/o moms who all have the same look, which involves wearing athletic apparel and a cap all day, a certain tone of voice, and the inability to envision exercising outside, except for running.
Seriously, these people act like they are still in middle school. There is one who occasionally comes to my boot camp class. One day, our regular instructor was not there and when she saw a sub, she had a melt down, started whining and getting really agitated saying that she was going to have to "not eat all day" because she wasn't going to burn enough calories. It was scary to see and I thought I was going to have to go into professional mode.