" 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. 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. Nike Air Womens Running Shoes The most common running related injuries are due to over-use. Repetitive stress on the same tissues without enough time for recovery or due to improper form or muscle imbalances, leads to many of the above. "

" Another injury prevention method that is very commonly recommended in the running community, but is actually controversial is stretching. While stretching is often recommended as a near requirement to avoid running injuries, the relevant medical literature does not represent as much of a consensus that it is effective. Some studies find that it is and some find that it really isn't helpful at all. A 2002 systematic review of 27 peer reviewed studies found that there was not sufficient evidence to support the claim that stretching was effective in injury prevention or soreness reduction. [1] Most members of the running community find that the inconsistent study methods and the failure to establish proper controls and find proper stretching methods is the reason behind the conflicting studies, and stretching is in fact helpful, or at least not harmful. Types of running events Track running Road running Cross-country running Trail running Fell running Classification of running by distance Sprints Middle distance Long distance Ultrarunning Silent Running is a science fiction movie made in 1972, directed by Douglas Trumbull and starring Bruce Dern as the protagonist Freeman Lowell. It was made with a very limited budget but has since achieved a cult following. Nike Acg Running Shoes The movie depicts a dystopian future, in which all plant life on Earth is extinct and only a few specimens have been preserved in greenhouse-like domes attached to a fleet of three American Airlines "Space Freighters" positioned just outside of the orbit of Mars. Lowell, a crew member aboard one of these ships, the "Valley Forge", is in constant disagreement with his other, human crewmates, who are anxious to return to a bleak and deforested yet familiar Earth. "