Yoga techniques have been used throughout the past and have shown an consistent physiological changes. Hatha yoga was used in this study because of it deals with physical training and performance through the breathing techniques used, not dealing with the mind and meditation. The breathing method used is called the Istity Method which consists of the prolongation or amplification of the steps of the breath (breathing in-out) with short regular rest intervals. The volunteer for the study was a healthy 58-year-old with experience in yoga techniques. Heart rate, blood pressure, and corisol in the saliva were made just before starting the exercise, then five, fifteen and thirty minutes after the exercise ended. During the breaks, the subject performed the Istity method breathing, lasting three minutes, with the mouth closed, breathing in and out through the nose. The Istity Method had a significant effect on the blood pressure and heart rate in that the increase in each was notably lower with the Istity Method breathing than with regular breathing. This study shows that the Istity Method, a breathing exercise, reduces the cortico-adrenal and cardiovascular response to stress (Monnazzi et al., 2002).
Cognitive appraisal can dramatically affect stress. Folkman and Lazarus define stress as "a relationship between an individual and the environmental demands that he or she is facing" (Ennis et al., 2001). Individuals view the occurrences around them differently from one another and each has to decide if the events are stressors. Two individuals can view the same stressor differently, so much that one may view the event as stressful while the other may not. Therefore, changing the way a person views an event can change the amount of stress, if any, he or she may feel. In a study measuring catecholamine levels before and after a test, Ennis et al. took two groups of students. One group had a challenge appraisal of the test while the other had a threat appraisal of the test.