The “Fight or flight” response is a natural process that is designed to protect your body from harm.
When you think about negative consequences, a part of your brain, the hypothalamus, activates and triggers the pituitary gland to secrete the hormone ACTH. This hormone stimulates the adrenal glands in your kidneys and results in the release of adrenaline into your blood. It is at this point in the process when many of us experience the reactions of this process. Your neck and back muscles contract (forcing your head down and your spine to curve) moving your posture into a slouch.
In 1982, a team of psychologists watched pool players play alone or in front of crowd. The study found that stronger pool players sank more shots when performing in front of a crowd, while poor pool players performed worse. Interestingly, the stronger pool players performed even better when people were watching them versus when they were playing alone.
Breathing and stretching before going on stage activates the hypothalamus and sends out hormones to trigger a relaxation response. Researchers tested a single session of slow breathing on 46 trained musicians, and the results of the study found that one session of slow breathing helped control arousal, especially for musicians that had high levels of anxiety.
Watch this video of Steve Jobs presenting the first iPhone.
This lesson is adapted from Mickael Cho's article about the science of public speaking. It starts like this: "Palms sweaty. Heart racing. You know the feeling. Whether it’s five people or fifty, public speaking is a gut-wrenching experience for most of us."