" Competitive running Perhaps the most basic of athletic contests, running races are simply contests to determine which of the competitors is able to run a certain distance fastest. Today, competitive running events make up the core of the sport of athletics . Running competitions have probably existed for most of humanity's history, and were a key part of the ancient Greek Olympics, as well as the modern Olympic games. Events are usually grouped into several classes, each requiring substantially different athletic strengths and involving different tactics, training methods, and types of competitors. Running affects not only the body, but the mind as well. Runners who finish a great run are often said to have a "runner's high" - a strong feeling of accomplishment and pride. Some sources point to the origin of a runner's high being increased endorphin production as a result of exercise. Houston Texan Running Of The Bulls Running injuries There are many injuries associated with running (due to it being a high impact activity). Common injuries are "runner's knee" (pain in the knee), shin splints, pulled muscles (especially the hamstring), "jogger's nipple" (soreness of the nipple due to friction), twisted ankles, and Iliotibial Band Syndrome. "

" In this case, the governor and lieutenant governor run separate campaigns and can be from two different political parties. This was the case when George W. Bush was Governor of Texas. His first lieutenant governor, Bob Bullock, was a Democrat. In cases like this, the governor and lieutenant governor are not considered running mates because they are not elected on the same ticket. Running mates are often chosen to balance the ticket. That is to create more widespread appeal for a ticket by expanding it appeal across geographic or ideological lines. 2004 Bull Running Spain This was especially true in presidential elections before the American Civil War when northern candidates were often paired with southern candidates and visa-versa. Electoral votes also play a part in modern presidential running mate selection. "