The NFL, the professional American National Football League is the most important and influential league of the United States. Its championship final is the famous Super Bowl, which is the most TV-watched sporting event in all the United States. The American Football is a sport that has a tradition of more than 100 years in the USA. It is an evolution of the English rugby and it's a very competitive sport. Due to the complexity of strategies that it requires, it is necessary to have a great discipline, a strong physical training and a good mental preparation.