Endorphins, the body's natural pain killers and exercise

The word is derived fromendogenous ( inside the body) and morphine( morphine like effect)

Hence , endorphins are chemicals produced by the brain during certain periods that have effects similar to morphine and other opioid drugs. They however, do not cause dependence and addiction like the drugs.

Another significant difference is with regard to the duration of action. Endorphins ( which are made up of smaller subunits of proteins called peptides ) are rapidly degraded by the body's enzymes unlike externally administered drugs which tend to act for long periods.

Their effect is brought about by activating certain receptors and modifying the transmission of other chemicals that communicate between nerve cells. Endorphins are most commonly released during periods of pain and stress.

In addition to lowering pain, they also have several positive effects on mood and even boost the immune system. This has potential implications in management of precancerous cells and research is going on in this regard.

Mood elevating effects are commonly seen after exercise and is the basis of the term 'runners high' .

While the extent of endorphins' contribution to this is still a matter of debate among scientists, what is clear is that endorphins are found in higher concentration after bouts of exercise.

Typically, half an hour of continuous, moderately intense exercise releases endorphins.

For those less inclined to strenuous athletic activity , there is good news.

Other triggers for endorphin release include eating chocolates or chillies, sex, massage, acupuncture, laughter and meditation.

Its another known fact that endorphin levels differ among people. Apart from resting levels, the amount of activity required or the duration of the response also varies tremendously.

In another promising research area , similar pathways to the endogenous opioid system have been discovered with even more wide ranging effects such as memory , anxiety , sleep and appetite. Potential drugs targeting these areas are of great promise and indeed exciting times are ahead.

We now have yet another reason to exercise regularly. If nothing else, it simply makes us feel good and increases our immunity.

Care must be taken however , not to overdo it. High endurance and intensity exercises done for long periods of time ( for eg. triathlons and marathons ) results in the body also producing steroids to cope with the stress, thereby temporarily decreasing immunity. In such cases , enough time should be given for rest and recovery.