During a relay race, members of a team take turns running, usually with a baton, parts of a circuit or performing a certain action. Relay races take the form of professional races and amateur games. In the Olympic Games, there are several types of relay races that are part of track and field.
Based on the speed of the runners, the generally accepted strategy used in setting up a 4 person relay team is: second fastest, third fastest, slowest, then fastest (anchor). Each segment of the relay (the distance run by one person) is referred to as a leg.
Each runner must hand off the baton to the next runner within a certain zone, usually marked by triangles on the track. In sprint relays, runners typically use a "blind handoff", where the second runner stands on a spot predetermined in practice and starts running when the first runner hits a visual mark on the track (usually a smaller triangle). The second runner opens his/her hand behind her after a few strides, by which time the first runner should be caught up and able to hand off the baton. Usually a runner will give an auditory signal, such as "Stick!" repeated several times, for the recipient of the baton to put out his hand. In middle-distance relays or longer, runners begin by jogging while looking back at the incoming runner and holding out a hand for the baton.
In track and field, the two standard relays are the 4x100 meter relay and the 4x400 meter relay. Traditionally, the 4x400 meter relay finals are the last event of a track meet, and is often met with a very enthusiastic crowd, especially if the last leg is a close race. It should be noted that it is hard to measure exact splits in a 4x400 (or a 4x100) relay. For example, if a team ran a 3:00 4x400, it does not mean every runner on the team has to run a 45 second open 400, because a person starts accelerating before he/she has the baton, therefore allowing for slightly slower overall open 400 times. A 4x400 relay generally starts in lanes for the first leg, including the handoff. The second leg then proceeds to run in lanes for the first 100 meters, after which point the runners are allowed to break into the first lane on the backstretch, as long as they do not interfere with other runners. A race organizer then puts the third leg runners into a line depending on the order in which they are running (with the first place closest to the inside).
4x200, 4x800, and 4x1600 relays exist as well, but they are more rare, especially at the high school level, where schools generally have only one or two competitive strong runners in such events.
A team may be disqualified from a relay for:
- Losing the baton (dropping the baton)
- Making an improper baton exchange
- Making two false starts (or in some cases only one)
- Improperly overtaking another competitor
- Preventing another competitor from passing
- Willfully impeding, improperly crossing the course, or in any other way interfering with another competitor
The largest relay event in the world is the Penn Relays, which attracts over 15,000 competitors annually on the High School, Collegiate and Professional levels, and over its three days attracts upwards of 100,000 spectators. It is credited with popularizing Relay Racing in the sport of Track & Field.
Long distance relay races
The world's longest relay race is Japan's Prince Takamatsu Cup Nishinippon Round-Kyūshū Ekiden, which begins in Nagasaki and continues for 1,064 km.
A long distance relay race typically has runners traveling from 5 to 10 kilometer distances per leg and several legs per race. A race can be run over the course of a day, or may span two or more days with participants running throughout the night.
The largest long distance relay in the world is Hood to Coast relay race which takes runners from the top of Oregon's Mt. Hood to the Pacific Ocean in Seaside Oregon (315 km.).
The longest relay race in the United States at 216.6 miles is the Cascade Lakes Relay in Oregon that starts at Diamond Lake Resort and finishes in Bend, Oregon.
Two examples of a long distance relay race include (in Canada) the Shore to Shore Relay Race which runs 305 kilometers over two days with six to twelve runners, and (in the U.S.A.)
Other long distance relay race include: Wild West Relay (Fort Collins to Steamboat Springs) in Colorado Green Mountain Relay (Jeffersonville to Bennington) in Vermont Texas Independence Relay in Texas Sunrise to Sunset Relay which stretches coast to coast across Florida The 100 on 100 Heart of Vermont Relay 100 miles on scenic VT RT 100
Shorter long distance relay races have also proven to be popular. These shorter races range from 40 miles to 86 miles, but still incorporate the team aspect. The most popular ones in this category include: River To River Relay 80 miles in Southern Illinois Market To Market Relay 86 miles from Omaha to Lincoln, Nebraska  Brew To Brew 43 miles from Lawerence to Kansas City, Kansas, Lake Tahoe Relay which is approximately 70 miles around Lake Tahoe.
Medley relay events are also occasionally held in track meets, usually consisting of teams of four runners running progressively longer distances. The Distance Medley Relay consists of four legs run at distances of 400, 800, 1200, and 1600 meters. The Sprint Medley Relay usually consists of four legs run at distances of 400, 200, 200, and 800 meters, though a more uncommon variant of 200, 100, 100 and 400 meters (Sometimes called a Short Sprint Medley) also exists. See also Swedish relay.