My two daughters are currently on pre-team at our local gym. Our youngest daughter has been having a lot of nosebleeds lately (sometimes up to multiple times per week). Then my older daughter got one as well. We noticed that they typically happened the day or night of gymnastics practice (usually in the middle of the night or early morning). Then one of the other girls on the team came out of practice with a bloody nose and one of the other moms said it was from the chalk drying out their nose. Has anyone ever heard of this? Are there ways to prevent it?