Gymnastics meets are a good place to read since often your child’s team will not be in a rotation for an hour or more. I read Chapter 5 of Quiet. It talks about how to overcome your natural introversion when needed.
First Cain discusses how, despite outward appearances, brain scans still show signs of highly reactivity or low reactivity in adults. She cites studies that show that introversion and extroversion may just be people seeking their preferred level of stimulation. For instance when given a chance to set headphone volume when working introverts chose a lower level. Moreover when either introverts or extroverts had to work at a noise level the other group preferred performance decreased.
Cain then makes a metaphor with a rubber band. You can stretch your native personality type, but always prefer to return to the original setting. She closes the chapter by discussing a desensitizing approach she used to conquer her fear of public speaking.