Adrenaline, or epinephrine, is a hormone that dilates an individual's air passages and increases his heart rate when he is faced with a stressful situation. The hormone is secreted from the adrenal glands to help ensure survival under dangerous situations. Many people come to enjoy the surge of energy that comes with a rush of adrenaline and actively search out activities that will stimulate this stress response. Participating in sports, eating certain foods, or playing some computer games can increase this hormone.
Humans most likely evolved the ability to use adrenaline in order to act quickly and efficiently under pressure or when in harm's way. This hormone is the key trigger of the "fight or flight" response that is activated when an individual is faced with immediate danger, such as potential violence or bodily harm. Some people actively seek out extremely stressful situations in order to feel the rush associated with this experience. They may enjoy activities such as driving fast automobiles, engaging in heated debate, or studying martial arts.
Participating in sports activities is a well-documented method of increasing hormone levels. The fast-paced action of popular sports like football, basketball and lacrosse is similar enough to fight or flight emergencies to cause the production of adrenaline in the body. Other action junkies satisfy their need for a rush by becoming involved in extreme sports like surfing, snow boarding, motocross and rafting.
An individual can also increase the amount of the hormone that his adrenal glands secrete under stress by including certain foods in his diet. Diets that are particularly high in protein and caffeine will increase the amount that is released during stressful situations. Individuals who prefer to keep themselves in perpetual fight of flight mode throughout their day will find that they have a strong craving for excess sugar in order to provide for the next perceived emergency. Including healthy proportions of fresh vegetables and fish or chicken will ensure that a person has the proper nutrients on hand to balance the metabolism after reacting to an emergency situation.
In addition to diet, sports and dangerous situations, there are a handful of other methods of increasing adrenaline in the human body. Many computer games have been shown to simulate the types of real world situations that cause it to be released into the human body, particularly first person shooters, sports games and popular multiplayer role playing games.