What word best describes a behaviour in which one is boastful or proud of an attribute that most would consider undesirable?

What word best describes a behaviour in which one is boastful or proud of an attribute that most would consider undesirable? (E.g., "There ain't anyone around here dumber or fatter than me."

We may use the word , "Vainglorious" which is to mean a person of whom we are critical because he is proud of what he is or has done and boasts a lot about himself or his doings. A vainglorious attitude is not very likeable and can be annoying to be around. An example :

• The vainglorious trainer spent more time flexing his muscles and talking tall than he did helping build his clients.