running became popular as a form of exercise largely because of two coaches in the mid-twentieth century. the first, arthur lydiard, coached runners in his homeland of new zealand as well as in mexico, finland, denmark, venezuela, australia and turkey.

as a young athlete, he trained using the customary method of running long distances non stop - after experiencing great difficulty in an 8 kilometer run, the worried lydiard began heavily researching physiology - from his research he discovered the benefits alternating heavy and light training. from these modificiations lydiard founded the concept of training both speed and distance commonly used today.