Professional vocal/speech coach Roger Love says chest breathing is much more powerful and effective for speaking than throat breathing. To find out if you are chest breathing of throat breathing, start speaking and, while you are still speaking, pinch your nose closed. If your voice sounds the same, you are chest breathing, if it suddenly becomes hard to speak and understand what you are saying, you are throat breathing. To learn chest breathing, see the earlier entry titled "Nose breather".
Professional Speech Coach
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