It seems that our species simply has not evolved quickly enough to deal with the daily demands of the typical urban lifestyle. The habits and routines that helped keep earlier generations fit and provided a balance that reduced stress just aren’t there any more.
We lead a more sedentary lifestyle and our work tends to involve less physical activity. The pace of life is quicker too, leaving less time for reflection and introspection; many people are chronically over-stimulated and shun boredom as though it was a disease.
Of course a certain amount of stress is necessary and beneficial. But even those who thrive on competition, stimulus and demand, must learn to balance this with periods where they can withdraw, reflect and make sense of the world if they are to remain effective. Most people know this intuitively, which is why a common treatment for stress is ‘time off’.