I need a stability ball. A stability ball is a great addition to standard workouts as they help core muscles to activate. Core is what supports your posture and daily functions, but often overlooked and underutilized while working out.
I am not an introvert but I love and respect a great many people who are. I wish more people would understand what it means to be an introvert - maybe you are and you don't even realise. Introversion does not equal shyness.