The physical reactions to stress are natural defense mechanisms intended to deal with the threat of predators and aggressors. Let’s start with a medical definition of stress: A physiologic reaction by an organism to an uncomfortable or unfamiliar physical or psychological stimulus. Biological changes result from stimulation of the sympathetic nervous system, including a heightened state of alertness, anxiety, increased heart rate, and sweating.
The less control you have over any of these events and the more uncertainty they create, the more likely you are to feel stressed. physical challenges definition of stress psychological stress, is that it’s a type of strain that affects a person mentally, physically, and emotionally.  It’s your body’s “fight-or-flight” adrenaline response. Your body instantly shifts into high gear to deal with the emergency.

The definition of stress extends to the “three types” of stress.

Acute Stress: This is the most common and it comes from events of the recent past or those anticipated in the near future. These are primarily the daily events of life: The fender bender. Missing the commuter train.  A big mistake at work. Losing cable TV during the Super Bowl. And so on. Today there are also many psychological “threats” to contend with. For example: Moving, divorce, troubles or challenges at work, exams at school.

A form of acute stress is “eustress” which can be defined as a form of positive stress. In some situations you benefit from stress because it gives you your competitive edge in sports, giving a speech, job interview, or acting. Eustress provides you with focus to help you think quickly and clearly.

Eustress also keeps you vital and excited about life. Examples include the excitement of a fast challenging run down the ski slope, a roller-coaster ride, or a scary movie. Nonetheless, too much eustress can still tax your body. So be sure to have some “down time” to keep a healthy balance in your life.