Runner

Running is a method of terrestrial locomotion by which humans and other animals move quickly on foot. Running has an aerial phase in which both, or all, feet are above the ground at some stage (though there are exceptions). This is in contrast to walking, a slower form of movement where at least one foot is always in contact with the ground. The term "running" can refer to a variety of speeds ranging from jogging to sprinting. All forms involve the same basic stages of a main propulsion phase, where the person drives forward the hardest leading with one leg; a foot placement phase where they place their foot, absorb any impact and stabilise themselves- they regain their sense of balance and recover energy; they then start a new propulsion phase, this time with the other leg. This sequence continues and together forms a flow of actions which constitutes the runner's gait. Running has been described as the world's most accessible sport.

In sports science, the analysis of running can involve the categoristation of a person's gait into numerous different phases and identify multiple involved factors. For example, from the viewpoint of spring-mass mechanics changes in kinetic and potential energy within a running stride co-occur, with energy storage accomplished by springy tendons and passive muscle elasticity.

Running in humans is associated with improved health and life expectancy. Competitive running grew out of religious festivals in various areas. Records of competitive racing date back to the Tailteann Games in Ireland between 1171 BCE and 632 BCE, while the first recorded Olympic Games took place in 776 BCE. It is hypothesized that the ancestors of humankind developed the ability to run for long distances about 2.6 million years ago, probably to hunt animals.