Harness racing use a standing start. The sulky (informally known as a "bike") is a light, two-wheeled cart equipped with bicycle wheels. The driver (not a "jockey", as in thoroughbred racing) carries a light whip chiefly used to signal the horse by tapping and to make noise by striking the sulky shaft. There are strict rules as to how and how much the whip may be used; in some jurisdictions (like Norway), whips are forbidden. For exercising or training, the drivers use what is known as a "jog cart," which is a sulky that is heavier and bulkier than a racing unit.
Horses in the Middle Ages increased the importance and use of horses in harness, particularly for ploughing and other farm work, was the horse collar. The horse collar was invented in China during the 5th century, arrived in Europe during the 9th century, and became widespread throughout Europe by the 12th century. It allowed horses to pull greater weight than they could when hitched to a vehicle by means of yokes or breastcollars used in earlier times. The yoke was designed for oxen and not suited to the anatomy of horses, it required horses to pull with their shoulders rather than using the power of