Eustress means a good stress. It is simply a beneficial stress. It is caused by reactions of the nerves when the body is faced with a non overwhelming challenge.
Eustress is the positive reaction a person has to a stressor which depends on one's mood or even location. It occurs when there is a strain on what a person has and what a person wants but this strain is not so much that it will over burden one.
The term was derived by Hans Selye who was an endocrinologist. It could be physical,biochemical or even psychological. Eustress makes you excited and it makes you fulfilled. It makes one confident.
Example of Eust reason could be stress from a project at work or a workout training schedule.
