Euphoria!

We've all experienced that euphoric high of a rush of adrenaline. These feelings usually hit us after doing something terrifying, such as parachutingor bungee jumping,but they can also occur after a difficult presentation or strenuous exercise, even after eating certain foods. It's this sensation of an 'endorphin high' that often motivates people to seek out dangerous adventures or work their bodies to near exhaustion. Endorphins are natural components released from the pituitary gland in the human brain and are powerful enough to block sensations of pain, producing these feelings of euphoria. Endorphins attach to receptors on the outer surfaces of brain cells, essentially acting like chemical keys fitting into locks. If enough endorphin is inserted into the outer keyhole of a nerve cell, then that cell won't be able to convey pain messages to the conscious part of the brain.

Endorphins are also important for regulating blood pressure and body temperature. During stressful times, when endorphins are released, heart rate reactivity is lower. These natural 'opiates' are 100 times more powerful than heroin and morphine.

So how do we get our brains to release this substance? There are several things that stimulate the release of endorphins including meditation, laughing and even a positive attitude. Drugs, alcohol, certain types of food such as chocolate and chillis, have also been found to cause the brain to produce endorphins, but often with some unwanted side effects.

One stimulus that makes our brains produce endorphins in large amounts is intense aerobic exercise. This was discovered by accident in the 1970s when scientists were researching drug addiction. Often referred to as the 'runners high', the post exercise surge in endorphins has aided researchers in explaining why many people become addicted to their sport.

Researchers from the University of Richmond in the United States looked at whether weight lifting could also heighten the endorphin levels. Six resistance trained athletes completed three sets of eight reps of strength training using weights.

All of the exercises were performed at 80 per cent of their maximum effort. Their blood levels of endorphins were checked before and after the weightlifting. The study found that compared to cycling strenuously for 60 minutes, 24 repetitions of resistance exercise is fairly meagre. The results may have been far different if the weight trainers had lifted for a longer period of time or had done a type of circuit training.