Stress is a response of the body to a variety of internal and external stimuli. External triggers may include a job change, a move to a new city, marriage, death of a loved one, or an illness in your family. Internal stimuli may include physical or mental discomfort.
Stress can produce either negative or positive reactions.
For instance, you may strive for perfection because you feel inadequate, and the constant pressure you put on yourself may ultimately work against you. On the other hand, you may experience pressure positively and become highly motivated and productive, thus achieving more than you would under normal circumstances. Be it positive or negative, stress does produce physical reactions. The body releases hormones and chemicals that accelerate the function of the heart, lungs, muscles, and other organs. This response may be protective, enabling you to escape from a careening car, for instance.