Stress is not as bad as its reputation. A little stress is like the salt in the soup. Without this kick, life would be bland. Stress simply makes us better! We are fitter, clearer in the head, have more tension in the muscles and also in the mind.
No matter if you have to give a lecture or do an important job. Without a portion of stress you would simply not succeed in many things.
But, unfortunately, we have a bit much of this stress. I.e. not everyone and certainly not only managers. It is mainly people with high motivation, high accuracy and high sensitivity. And that has a variety of consequences.