When you’re scared, your body automatically defers to certain behaviors. You hug yourself or clasp your neck. When you’re victorious, your body also defers to certain behaviors such as throwing your hands up in the air and perhaps even yelling in excitement.
Here’s the interesting thing: you can reverse that interaction. If you’re feeling scared, just assume a victorious posture. In so doing, your brain increases testosterone (therefore increasing the feeling of dominance) and reduces cortisol (therefore reducing the feeling of stress). Your fear suddenly changes to excitement.
Amy Cuddy delivers an emotionally powerful talk on this subject on TED (see below). Body language is real language. It’s communication to both the outside world and your mind. So, assume a powerful posture and you’ll be telling your brain and the world what you actually feel, which is increased dominance and reduced stress.