@Moldova – I totally agree with you. I think that fitness instructors also have to make sure that the students are using proper form and are breathing correctly.
They have to monitor students that are becoming increasingly flushed and out of breath. It is really important that they offer alternative exercises to these students so that they don’t harm themselves.
They really have to be alert as to what is going on in the class because when students do the exercises incorrectly they risk having an injury.