The 100-meter sprint is an exciting event. One of the truest forms of human competition, sprinters must run in a straight line as fast as possible. The winner of the 100-meter sprint is the first runner to cross the finish line. Competition rules for the 100-meter sprint are governed by the International Association of Athletics Federations (IAAF).
Every 100-meter sprinter must begin the race with his feet in the starting blocks. The official race starter will call the sprinters to their blocks and on command the runners will adopt a set position. The set position requires the runners to have both feet in the blocks and adopt a position with the body weight on their hands. On the starter's gun all runners begin the race.
A false start is called when the feet of a runner leave the starting blocks before the starter’s gun. In youth and amateur events a false start is called by the starter or an assigned race referee. At international competitions technology to measure false starts must be in place. The IAAF website explains that a false start is ruled when the reaction time of a runner is less than 0.12 seconds after the gun. Reaction time is measured by pressure on the blocks, with 0.12 seconds being the natural time it is ruled to take for information to process from the brain to the muscles.
The width of a lane is specified by the IAAF rules or the governing body of a 100-meter sprint event. Any 100-meter sprinter who leaves her lane or obstructs the path of another sprinter will be automatically disqualified from the race. Stepping on the white lines is ruled as having left your lane during the race. In these circumstances, the race referee can order the race to be run over again if it is deemed necessary.
The finish is the decisive stage of the race, and is very exciting when sprinters are close to each other in terms of ability. The IAAF rules state that the time of a runner is recorded when the trunk of the body crosses the finish line. In youth and amateur 100-meter sprint races the winner is decided by a race referee at the finish line. In international competition IAAF rules require technology to be installed to record finish times. Times are recorded and reported to .01 seconds.