Stress is defined as the body's nonspecific response to any external demand, or stressor. Stressors can be positive or negative, but frequent and prolonged stress linked to negative experiences tends to have harmful effects.
According to researcher Hans Selye, who pioneered the modern study of stress, stress occurs in three main stages:
- Alarm reaction - The body's resources mobilize to deal with the stressor.
- Resistance - The body manages to cope with the demands of the stressor due to the initial mobilization of the alarm stage.
- Exhaustion - Adaptive resources are depleted; the body is less able to handle new stressors. This stage may lead to disease.
Understanding the stages and effects of the body's stress response is key to managing and reducing your own stress levels.