They never fell out when walking to class, or when running on a treadmill. Great for arm workouts. I use these for my office calls as well and no one complained about bad audio or background noise. 5-13 in Adidas or Nike running shoes. One of my important thumb drives got run over by a car and it was crushed. Dreadfully overpriced, no value for money and, in my opinion, pretty poorly made. The sound quality is crisp with a good level of basefor balance. Beads seem OK. When I pulled the pieces out of the box, I was thinking, oh hell no, this is not going to hold all that weight from the bottles. Needs to be taken down