Stress can act both good and bad for you. When you get right amount stress, you may perform at your muximum potentioal. However, when you get too much stress, you may under perform. That is a part of hour body's mechanism to protect ourselves.
In 1967, Homes and Rahe developed a questionnaire called the Social Readjustment Rating Scale (SRRS) for identifying major stressful life events. 43 life events are scaled depending on the impact of stress in the scale. Top of the list is Death of Spouse or Significant Other (100 points), followed by Divoce (73) and Marital Separation (66). Even "good" events such as Marrage (50), Vacation (13) and Christmas (12) can cause you some stress.
If you want to assess your current stress condition, check on SRRS list and add up the scores for each event expereinced over a 12 month period. If you have less than 150, you have little chance of suffering from stress. On the other end, if you have more than 300, you are likely to developing stress related illness.
Earlier this week, I felt sick and had to go to see a doctor. When I look back my recent life, I exterienced Business Reajustment, Change in Health of Family Member and Change in Residence, which themselves already accumleted more than 100 points in SRRS. I guess my body is sending a warning sign that I would surpass my stress limit if I continue to force myself in this pace.
So, keep your maximum performance in the long run, I think, it is extreamly important to make long time action plan by using such as dialy style calender and spread out "big events" that cause you a lot of stress.