Question: Racing flats, or simply flats, are lightweight athletic shoes designed for "long distance" track and field, cross country, and most often, road running, the sport of running on a measured course, over an established what?

full_context: Document 1: Locomotor effects of shoes: Locomotor effects of shoes are the way in which the physical characteristics or components of shoes influence the locomotion neuromechanics of a person. Depending on the characteristics of the shoes, the effects are various, ranging from alteration in balance and posture, muscle activity of different muscles as measured by electromyography (EMG), and the impact force. There are many different types of shoes that exist, such as running, walking, loafers, high heels, sandals, slippers, work boots, dress shoes, and many more. However, a typical shoe will be composed of an insole, midsole, outsole, and heels, if any. In an unshod condition, where one is without any shoes, the locomotor effects are primarily observed in the heel strike patterns and resulting impact forces generated on the ground.
Document 2: Road running: Road running is the sport of running on a measured course over an established road (as opposed to track and field and cross country running).
Document 3: Middle-distance running: Middle-distance running events are track races longer than sprints, up to 3000 metres. The standard middle distances are the 800 metres, 1500 metres and mile run, although the 3000 metres may also be classified as a middle-distance event. The 1500 m came about as a result of running three and 3/4 laps of a 400 m outdoor track or 7 and a half laps of a 200m indoor track, which were commonplace in continental Europe in the 20th century.
Document 4: Open Road Racing: Open Road Racing is a form of regularity rally carried out at high speeds on closed public highways, most commonly in sparsely populated parts of the Southwestern United States. Competitors attempt to set specified average speeds which can range from 80 to or higher along courses ranging between 50 and in length. At the lower speeds, unmodified production cars can be used, while straightforward safety modifications can permit powerful sports cars to reach speeds of 165 mph .
Document 5: Cross country running: Cross country running is a sport in which teams and individuals run a race on open-air courses over natural terrain such as dirt or grass. Sometimes the runners are referred to as "harriers" (dogs). The course, typically 4 - long, may include surfaces of grass, and earth, pass through woodlands and open country, and include hills, flat ground and sometimes gravel road. It is both an individual and a team sport; runners are judged on individual times and teams by a points-scoring method. Both men and women of all ages compete in cross country, which usually takes place during autumn and winter, and can include weather conditions of rain, sleet, snow or hail, and a wide range of temperatures.
Document 6: 5K run: The 5K run is a long-distance road running competition over a distance of five kilometres (3.1 miles). Also referred to as the 5K road race, 5 km, or simply 5K, it is the shortest of the most common road running distances. It is usually distinguished from the 5000 metres track running event by stating the distance in kilometres, rather than metres.
Document 7: Track and field: Track and field is a sport which includes athletic contests established on the skills of running, jumping, and throwing. The name is derived from the sport's typical venue: a stadium with an oval running track enclosing a grass field where the throwing and jumping events take place. Track and field is categorised under the umbrella sport of athletics, which also includes road running, cross country running, and race walking.
Document 8: List of shoe styles: This is a list of shoe styles and designs. A shoe is an item of footwear intended to protect and comfort the human foot while doing various activities. Shoes are also used as an item of decoration. The design of shoes has varied enormously through time and from culture to culture, with appearance originally being tied to function. Additionally, fashion has often dictated many design elements, such as whether shoes have very high heels or flat ones. Contemporary footwear varies widely in style, complexity and cost. Shoemaking is the process of making footwear. Originally, shoes were made one at a time by hand. Traditional handicraft shoemaking has now been largely superseded in volume of shoes produced by industrial mass production of footwear, but not necessarily in quality, attention to detail, or craftsmanship.
Document 9: Shoe: A shoe is an item of footwear intended to protect and comfort the human foot while the wearer is doing various activities. Shoes are also used as an item of decoration and fashion. The design of shoes has varied enormously through time and from culture to culture, with appearance originally being tied to function. Additionally, fashion has often dictated many design elements, such as whether shoes have very high heels or flat ones. Contemporary footwear in the 2010s varies widely in style, complexity and cost. Basic sandals may consist of only a thin sole and simple strap and be sold for a low cost. High fashion shoes made by famous designers may be made of expensive materials, use complex construction and sell for hundreds or even thousands of dollars a pair. Some shoes are designed for specific purposes, such as boots designed specifically for mountaineering or skiing.
Document 10: High-heeled footwear: High-heeled footwear (often abbreviated as high heels or simply heels) is footwear that raises the heel of the wearer's foot significantly higher than the toes. When both the heel and the toes are raised equal amounts, as in a platform shoe, it is technically not considered to be a high heel; however, there are also high-heeled platform shoes. High heels tend to give the aesthetic illusion of longer, more slender legs. High heels come in a wide variety of styles, and the heels are found in many different shapes, including stiletto, pump (court shoe), block, tapered, blade, and wedge.
Document 11: Trail running: Trail running is a sport which consists of running and hiking over trails. In the United Kingdom and Ireland it is also called mountain or fell running although the two types do differ. It differs from road running and track running in that it generally takes place on hiking trails, often in mountainous terrain, where there can be much larger ascents and descents. It is difficult to definitively distinguish trail running from cross country running. In general, however, cross country is an IAAF governed discipline that is typically raced over shorter distances (rarely over 12 kilometers), whereas trail running is loosely governed, and run over longer routes.
Document 12: Parkrun: Parkrun (styled as parkrun) is the name given to a collection of five-kilometre running events that take place every Saturday morning in fifteen countries across five continents. Each Parkrun territory has its own sponsors. Events are run by volunteers, and participation is free of charge.
Document 13: Cross country running shoe: Cross country running shoes are made for both cross country running and long distance running. Season-specific trainers are available for different types of training.
Document 14: Platform shoe: Platform shoes are shoes, boots, or sandals with an obvious thick sole, usually in the range of 3 - . Platform shoes may also be high heels, in which case the heel is raised significantly higher than the ball of the foot. Extreme heights, of both the sole and heel, can be found in fetish footwear such as ballet boots, where the sole may be up to 20 cm high, and the heels up to 40 cm and more. The sole of a platform shoe can have a continuous uniform thickness, have a wedge, a separate block or a stiletto heel. Apart from the extreme forms of fetish shoes (which are first and foremost not intended for walking in), walking in platform shoes can be cumbersome and clumsy. Raising the ankle increases the risk of a sprained ankle.
Document 15: Racing flat: Racing flats, or simply flats, are lightweight athletic shoes designed for "long distance" track and field, cross country, and most often, road races. They differ from normal training shoes mainly by the lack of a substantial heel (hence the name).
ground_truth: road