When a threat is perceived, the nervous system
responds by releasing a flood of stress hormones, including
adrenaline and cortisol. These hormones rouse the body for emergency
action.
Physiologically, the heart pounds
faster, muscles tighten, blood pressure rises, breath quickens, and
your senses become sharper. These physical changes increase strength
and stamina, speed up reaction time, and enhance focus. This
is known as the fight or flee response to the event. Or the
stress response. It is present in all humans and animals.
Without this neither would have survived.