Devices systems and methods are disclosed. Among other things, the devices systems and methods can facilitate ergonomic gripping of a handle； conform to the shape of a wrist； enhance golf techniques or performance； enhance racket sport technique or performance； protect a head of a user engaged in contact sports or other hazardous activities； identify concussions, in some cases in substantially real time； provide sterilization of garments； control surgical robots； allow for medical treatment of multiple subjects without disrobing； provide biometric or other data； and/or be used to train muscles or body parts for, for example, performing specified tasks using a body part.
