hi, how you, i have two students that when they do inversions especially with the feet above the head, even when there backs are flat on the floor as in shoulder stand they get very dizzy and even go pale, i have tried to adjust but nothing is working so my instincts have told me to not let them do it anymore, they are fine with downward dog, i think this could be a medical problem maybe diabities but not i think could be something else thats causing such an influx of blood to the brain, can you shed some light for me im curious thanks