Stress is the emotional and physical tension brought on a person’s reaction to the demands of life. Stress frequently causes anxiety, irritability, and inability to concentrate. Stress can also lead to headaches, and a rapid heartbeat.
- Stress becomes traumatic when danger, risk, fear or anxiety is present. --Patrick Carnes The Betrayal Bond, page 3
Author John A. Schindler, M.D. introduced the powerful concept of EII, or "emotionally induced illness," long before most physicians were aware of the connection between emotions and physical health. (1954) 
Many illnesses, such as chronic anxiety states, high blood pressure, heart disease, and addictive disorders, to name a few, also seem to be influenced by chronic or overwhelming stress. 
Learn to relax. Your body is precious, as it houses your mind and spirit. Inner peace begins with a relaxed body. Norman Vincent Peale
When we feel love and kindness toward others, it not only makes others feel loved and cared for, but it helps us also to develop inner happiness and peace. The Dalai Lama. (much better if no reward is expected)
I am always busy, which is perhaps the chief reason why I am always well. Elizabeth Cady Stanton.
We don't stop playing because we grow old; we grow old because we stop playing. George Bernard Shaw.
Be absolutely determined to enjoy what you do. Gerry Sikorski. (better if you explore your creativity)
We do not sing because we are happy, we are happy because we sing. William James.
What makes people happy is activity; changing evil itself into good by power, working in a God like manner. Johann Wolfgang von Goethe.
Fill your life with as many moments and experiences of joy and passion as you humanly can. Start with one experience and build on it. Marcia Wieder.
As long as you derive inner help and comfort from anything, keep it. Mahatma Gandhi.
"Health is the vital principle of bliss, and exercise of health." James Thomson.
As time goes on, increase activity until you exercise on most days. You'll feel better physically, sleep better at night, and improve your mood. Join an exercise group or exercise with a friend. You'll stay connected. And you'll have support to help you stay on track! 
Lack of activity destroys the good condition of every human being, while movement and methodical physical exercise save it and preserve it. Plato.
Be physically active. Any activity’s better than none. Health benefits grow the more you do. 
The body needs material food every day. The soul needs spiritual food. To start consider a yoga or meditation class or simply listen to music while taking a long, hot bath. Meditate daily, and soon your inner strength and mind power will grow.
A free and silent mind is always in meditation. Make meditation a daily practice, and it will soon turn into a habit. Concentrate on your consciousness and find out what it is. You may be surprised at what you find. 
Practice breathing techniques or try a massage. Also helps spending time with your pet or smile and laugh; it is said that: Laughter is the best medicine. Rent, buy or see a hilarious movie. This is guaranteed to help. Smiling and laughing releases endorphins, which fights stress, helps to relax and reminds you that life is more than just work. Even if it feels strange at first, make it a point to smile more often. Ibidem: 
Listening to music can have a tremendously relaxing effect on our minds and bodies, especially slow, quiet classical music. This type of music can have a beneficial effect on our physiological functions, slowing the pulse and heart rate, lowering blood pressure, and decreasing the levels of stress hormones. 
- Breathing meditation
- Exercise: Martial arts, Tai Chi, Yoga
- Complementary medicine: Traditional Chinese medicine, Ayurvedic medicine, Naturopathy
- Herbert Benson
- Dale Carnegie
- "How To Live 365 Days A Year" by John A. Schindler.
- Tips for Exercise, Diet and Stress Reduction.
- How to Handle Angry People.
- How to Relax
- 20 Ways to Eliminate Stress From Your Life.