This biological response can save your life when you’re in real and urgent peril. Hormones such as cortisol and adrenaline flood your system, creating intense and immediate reactions: Your heart rate increases, your palms sweat, and you may feel the urge to run or hide until the danger goes away. This brings on the fight-flight-freeze response. Both activate the amygdala-the part of our brain that kicks on when we are in distress and perceive a danger (real or imagined).

Truth time: Our brains don’t know the difference between being chased by a tiger and being pinged by a triggering email. Heading out the door? Read this article on the new Outside+ app available now on iOS devices for members!