Gym Teachers: Too Harsh?

I will admit, I'm not too athletic, or really good at sports at all to be honest. Today in gym class, my gym teacher told us "If you can't hold your feet 6 inches above the ground for 40 seconds, you're stomach muscles aren't strong enough." Now, I can understand the point in that. I could only hold them up for about 30 seconds, and that's pushing it. Same went with many of the other kids in my gym class. I understand, we aren't in the greatest shape. However, my gym teacher proceded to tell us we were all getting fat and we eat too much and things like that. Personally, I find that kind of offending. I know gym teachers can be harsh, but I should think a 10th grade teacher could have more tact than to outright call her children fat. Children are not going to respong to that. They will only say "that woman is a *****" and be done with it. It will not make children do any better in gym class in my opinion. Most kids are not in gym class to get exerscise because they like it, they're in there because it is required and they just want to get it over with, with as little work as possible. I told my mother about this and she told me about how my generation is the first generation to have a lower life expectancies than our parents because we are so out of shape. Maybe this is true, but I don't believe this makes it okay to call a child fat or to insult them they way my teacher did today. You're opinion?