Extreme sports are those sports or leisure activities with a sports component that could pose a real or apparent hazard or extreme difficult conditions in which they practice. Under this concept are grouped many existing sports that involve a certain amount of physical demands and, above all, mental. For example, include the most demanding sports in the hiking (ice climbing, rock climbing, etc..) And other recently established as (bungee jumping, snowboarding, etc.).. A sport, not considered extreme, can be defined and if practiced under special or unusual circumstances in the. For example, rock climbing a few inches of soil (boulder) is not considered "extreme sport", but if done on a vertical wall of rock several hundred feet, then it is applied to the term. One can estimate that a person practices a "extreme sport" where does it for the first time. For example, the decline of a class IV river is pretty extreme for those who never before had climbed to a raft and you will feel as far above their personal capacities. The fact living out of that experience will make them think they are good athletes, while his guide is relegated to the background, even if it was he who settled the vast majority of the problems of decline. The term "extreme sports" is not appropriate to apply when performing just a recreational activity or alternative tourism, nor should it be defined by environmental conditions, quite subjective and dependent on the degree of preparation. In contrast, the term can be applied when playing sports in the existing limits of development, whether climbing, athletics, gymnastics or whatever. However, it seems that the term will be eliminated (despite the lack of logic) of its current connotation, as it is to the liking of the public and marketers of beverages, food, food supplements or even snuff companies . Currently, in some countries are beginning to use the term "adventure sport" when playing sports higher risk than normal without being professionals. An example of this is the difference between "caving" and "Caving": the first refers to a scientific activity, while the second refers to those who practice sport.