An often-neglected part of the body when it comes to posting on social media. Great development of lats, delts, rhomboids and rotator-cuff elements can be impressive, as these guys who very clearly love their training are only too eager to show us! Many guys seem to neglect back and legs when working out, focusing on chest, abs and arms. Don't!  Start young:  

You can never spend enough time on your hands... Not good, but at least he is making an effort.