The relationship between psychosocial factors and psychophysiological reactions to a situation including stressors and relaxation in a working population was examined. A sample of 115 working men and women aged 26-65 was used. Each participant was examined at baseline, during deep breathing, experimentally induced stress and relaxation. Heart rate, exhalation carbon dioxide, oxygen saturation and blood pressure were monitored. Significant variations across experimental conditions were observed for all physiological variables. There was a pronounced lowering of blood pressure during deep breathing. Women showed significantly more pronounced physiological variation than men. Participants with low education reacted with significantly more systolic blood pressure elevation during the stressful conditions than others. The implication of the results for therapeutic and preventive exercises with deep breathing are discussed.