Just to add a few words about my previous post, here are some general recommendations if you are dealing with stage fright or any other kind of apprehension or anxiety: reduce your intake of coffee, tea, alcohol, tobacco and other stimulants a few days before the event. If you start to feel anxious or overly stressed, try “taking deep breaths.” There is an actual benefit to it.
A lot of us are used to shallow breathing that engages only the top part of the lungs, which does not fill them up completely. Breathing has three major functions: it brings in O2, eliminates CO2 and eliminates toxins. Therefore if you do not breathe properly you do not get a sufficient amount of O2 and do not eliminate by-products well enough. It also has an action on the nervous system.
There is a part of our nervous system that regulates our involuntary functions. (Luckily for us, digestion, breathing, heartbeat, etc. happen without us having to think about it.) It is called the autonomic (visceral/involuntary) nervous system (ANS) as opposed to our somatic (voluntary) nervous system (SNS) that commends the skeletal muscles. Some functions can be part unconscious part voluntary, such as breathing. The ANS is also divided into the Parasympathetic NS (in charge of rest and digestive activities) and the Sympathetic NS (involved mainly in the fight-or-flight situation). The later allows the body to function under stress and is responsible for increasing the heart rate, stimulating sweating, etc.)
When we are stressed, the sympathetic NS is stimulated and it leads to an increased heart rate, perspiration and tensed muscles. Breathing, especially abdominal/diaphragmatic breathing can be used to stimulate the parasympathetic nervous system, which leads to relaxation.
It is good to take some full breaths from time to time during your day, as a habit. Practice engaging the diaphragm. Deep breathing also massages the internal organs which is beneficial. This is one of the reasons why Yoga, among other activities, focuses so much on breathing. To see if you do it correctly, watch your stomach. It should expand when you inhale and flatten when you exhale. Your shoulders should not move up and down. Try this especially when you feel anxious, nervous or stressed. You will feel more relaxed!