Young Blonde Girl Naked On A Walkway

The word walk is descended from the Old English wealcan "to roll". In humans and other bipeds, walking is generally distinguished from running in that only one foot at a time leaves contact with the ground and there is a period of double-support. In contrast, running begins when both feet are off the ground with each step. This distinction has the status of a formal requirement in competitive walking events. For quadrupedal species, there are numerous gaits which may be termed walking or running, and distinctions based upon the presence or absence of a suspended phase or the number of feet in contact any time do not yield mechanically correct classification. The most effective method to distinguish walking from running is measurement via a force plate, but definitions based on the percent of the stride in which a foot is in contact with the ground (averaged across all feet) of greater than 50% contact corresponds well with identification of 'inverted pendulum' mechanics via force plate measurements for animals with any number of limbs.
Although walking speeds can vary greatly depending on factors such as height, weight, age, terrain, surface, load, culture, effort, and fitness, the average human walking speed is about 5 kilometres per hour (km/h), or about 3.1 miles per hour (mph). Specific studies have found pedestrian walking speeds ranging from 4.51 km/h to 4.75 km/h for older individuals to 5.32 km/h to 5.43 km/h for younger individuals. An average human child achieves independent walking ability around 11 months old.
A pedestrian is a person who is walking on a road, pavement or path.