Eustress

Eustress means beneficial —either psychological, physical (e.g. exercise), or biochemical/radiological (hormesis).

The term was coined by endocrinologist Hans Selye, consisting of the Greek prefix eu- meaning "good", and stress, literally meaning "good stress".

Eustress was originally explored in a stress model by Richard Lazarus, it is the positive cognitive response to stress that is healthy, or gives one a feeling of fulfilment or other positive feelings.Selye created the term as a subgroup of stress to differentiate the wide variety of stressors and manifestations of stress.

Eustress is not defined by the stressor type, but rather how one perceives that stressor (e.g. a negative threat versus a positive challenge). Eustress refers to a positive response one has to a stressor, which can depend on one's current feelings of control, desirability, location, and timing of the stressor. Potential indicators of eustress may include responding to a stressor with a sense of meaning, hope, or vigor. Eustress has also been positively correlated with life satisfaction and well-being.

Eustress occurs when the gap between what one has and what one wants is slightly pushed, but not overwhelmed. The goal is not too far out of reach but is still slightly more than one can handle. This fosters challenge and motivation since the goal is in sight. The function of challenge is to motivate a person toward improvement and a goal. Challenge is an opportunity-related emotion that allows people to achieve unmet goals. Eustress is indicated by hope and active engagement. Eustress has a significantly positive correlation with life satisfaction and hope. It is typically assumed that experiencing chronic stress, either in the form of distress or eustress, is negative. However, eustress can instead fuel physiological thriving by positively influencing the underlying biological processes implicated in physical recovery and immunity.

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