not have to win all or any of the individual stages to win overall). Three-week stage races are called Grand Tours. The professional road bicycle racing calendar includes three Grand Tours - the Giro d'Italia, the Tour de France, and the Vuelta a Espana. Randonneuring and ultra-distance Ultra-distance cycling races are very long single stage events where the race clock continuously runs from start to finish. Their sanctioning bodies are usually independent of the UCI. They usually last several days and the riders take breaks on their own schedules, with the winner being the first one to cross the finish line. Among the best-known ultramarathons is the Race Across America (RAAM), a coast-to-coast non-stop, single-stage race in which riders cover approximately in about a week. The race is sanctioned by the UltraMarathon Cycling Association (UMCA). RAAM and similar events allow (and often require) racers to be supported by a team of staff; there are also ultra-distance bicycle races that prohibit all external support, such as the Transcontinental Race and the Indian Pacific Wheel Race. The related activity of randonneuring is not strictly a form of racing, but involves cycling a pre-determined course within a specified time limit. Equipment The most commonly used bicycle in road races are simply known as racing bicycles. Their design is strictly regulated by the UCI, the sport's governing body. Specialist time trial bicycles are used for time trial events. Bicycles approved for use under UCI regulations must be made available for commercial sale and it is commonplace for amateur cyclists to own bicycles that are identical to those used to win major races. Clothing worn for road racing is designed to improve aerodynamics and improve rider comfort. The rider's shorts contain padding to improve comfort, and materials are chosen to manage rider temperature, manage sweat, and keep the rider as warm and dry as feasible in wet conditions. Cycling jerseys were originally made of wool; modern jerseys are made of synthetic fabrics such as lycra. Bicycle helmets were made mandatory for professional road racing in 2003, after the death of cyclist Andrey Kivilev. Tactics A number of tactics are employed to reach the objective of a race. This objective is being the first to cross the finish line in the case of a single-stage race, and clocking the least aggregate finish time in the case of a multi-stage race. Drafting Tactics are based on the