Ok, first is first, how does this happen?
The body's response to stress is called the General Adaptation Syndrome. It can be divided into three stages. The first stage being "Alarm Reaction". This is the flight or fight response, most of us don't actually run away or punch on but instead, the symptoms are blood pressure increases, muscles tense, digestion and elimination shut down, circulation patterns shift and glycogen is mobilised.
The second phase is long term stress, stress that isn't resolved by the flight or fight. The body then releases cortisol, fluid retention, hypertension, muscle weakness, osteoporosis, breakdown of connective tissue, non-productive inflammation, vertigo, headaches, weight gain, fatigue.
Next is the exhaustion phase. The body basically wears out and begins to breakdown. Some people choose to yell at others or drive aggressively to deal with the pressure but the best way to burn the fight or flight chemicals is to exercise. Massage also reduces the symptoms putting your body back on track.
One of my clients was very stressed out when he first started coming to see me and his doctor suggested he starts running and getting massages, take time out for himself to distress. He would see me once a week and run a few times a week and now he is happy! :)
it it really is that easy. Give it a try.