You should not be lifting your legs and/or crossing them. If you are and no one is correcting you, then you most likely are one of the small percentage of participants that all instructors face. We cue, coach, correct, and they don't change.
So after a while, we realize that our focus on this ONE person is detracting from the rest of the class, that this person will never listen because they feel that they know better, so we just let them do their own thing. It's frustrating, but this subject came up at an advanced training just this month. Participants who don't follow the class and use improper form - they're out there - and they're frustrating, but at some point you just smile, nod, and back away slowly, and spend your time and energy on the participants who want to get the most out of the class - like you!
SO. Please don't cross your legs or keep them in the air. Thank you from ALL of us for asking!
Certified
Body Combat and
Body Pump instructor, Spin certified cycle instructor, Certified Personal Trainer.