Exercise causes the release of several chemicals within the brain. An excellent example is the 'endorphin high' that a lot of runners get as the brain releases opiate-like chemicals which act as natural pain killers and which has been well documented.

The human brain is also responsible for the release of numerous neuro-transmitters like serotonin, norepinephrine and dopamine all of which have been shown to be beneficial in elevating mood. Once more, the effect of low levels of these nero-transmitters in causing depression, anxiety and sometimes even anger has been well documented.

As well as exciting the brain into producing chemicals that are of assistance in reducing stress, exercise also lessens the production of a number of chemicals that are a by-product of stress. For instance, if a person is placed under stress the sympathetic nervous system releases chemicals like cortisol and a number of hormones that, if left in the blood, may damage the blood vessels and produce scaring and even narrowing of the arteries.

Exercise can help in solving this problem in two ways. First, a good workout actually makes use of these compounds and breaks them down into harmless forms that are passed out of the body in the urine. Second, a good workout assists in strengthening the blood vessels and giving them increased elasticity so that they are able to better resist attack. One of the more common results of stress is tense muscles, especially in the shoulders, calves and neck and exercise will help to loosen these up.

As well as these various chemical effects there are also several psychological benefits that can be gained from following a regular exercise routine. Focusing your attention on a workout routine takes your mind away from the whole array of things that might be causing stress in your life and it is very difficult to concentrate on the things that are worrying you and to concentrate on your exercise routine at one and the same time.

This effect also helps to give your mind a chance to create what is known as homeostasis. Put simply this is a feedback mechanism within the body that acts to bring your body back into a state of equilibrium and a strenuous workout that diverts your mind from your problems will also give this system time to kick in.

Of course there are various other psychological benefits that result from a regular workout like the self-confidence that can be gained from simply improving your overall health and fitness. Here it is a case of 'if you look good then you usually feel good'.

As well, it helps you to recognize that you are using effort to improve your mind and body and that you are doing something that is positive rather than simply giving in to the feelings of helplessness and the passivity that generally go together with stress. It is all too easy to find that those things in your life that are putting you under stress have become the main focus of your attention and merely relegating them to the back of your mind will frequently lead to dramatic results.