The body reacts to stress in a number of different ways. A lot of the time it is the mind that has to take over when faced with a stressful situation to prevent the body from producing negative effects from it or even with a stronger mind the body is not affected at all from stress in some instances,
If psychological stress is handed out then it can be dealt with by having a strong mind. The body answers to stress negatively, whether it be mental or emotional. The only time I can think of either of these being a positive are in times of danger when it could keep you more alert and ready to avoid danger in a situation. Of course there is physical stress which is beneficial through exercise, causing hypertrophy and healthier cardio/respiratory system, but these are different types of stress. Regardless of what kind of stress it is, your body can cope with it as long as there is some kind of break or relaxation in between.
Continually getting hit with mental or emotional strength would take its course and begin to break down the body causing ulcers, skin irritations, mood swings and such as an initial phase. And if it were to continue then factors such as high blood pressure, anxiety, sleep disturbance and even psychological problems after a long period of time.
These are all things that you do not want in your life as a fit and healthy person. I suggest keeping stress levels to a minimum and any time you are encountered with a stressful situation, be aware of it and deal with it. Don’t let it eat away at you. The less stress equals the healthier body and mind.