The nature of stress

Stress is like electricity: the right amount gives energy and keeps us going; too much can damage us.

• Eustress: 'good' stress that improves performance, like the excitement before a match.
• Distress: harmful stress that wears us down.

Stress is our response to an event that disturbs our balance and exceeds our ability to cope. The events that cause it are stressors; our reaction to them is called strain.

Hans Selye, the 'father of modern stress research', defined stress as 'the non-specific response of the body to any demand': whatever the stressor, the body reacts in the same general way. Others argue that responses are more specific to the situation.

Why the same event stresses one person and not another: according to Richard Lazarus, it depends on how we appraise (judge) it:

• Primary appraisal: is the event a harm (damage already done), a threat (possible future harm), or a challenge (a chance to grow)?
• Secondary appraisal: do I have the resources (skills, time, help) to cope with it?

An exam is a threat to one student and a challenge to another. Appraisal decides stress.

Stress produces four kinds of reaction:

• Physiological: the 'fight or flight' response: racing heart, fast breathing, tense muscles;
• Emotional: anxiety, anger, irritability;
• Behavioural: disturbed sleep, eating changes, avoiding things;
• Cognitive: poor concentration, forgetfulness.

Stressors vary in intensity (how strong), duration (how long), complexity and predictability. Long-lasting, unpredictable stress is the hardest to bear.