Start (green) and end (red) points of a 100 metre race, marked on a running track
The 100 metres, or 100-meter dash, is a sprint race in track and field competitions. The shortest common outdoor running distance, the 100-meter (109.36 yd) dash is one of the most popular and prestigious events in the sport of athletics. It has been contested at the Summer Olympics since 1896 for men and since 1928 for women. The inaugural World Championships were in 1983.
On an outdoor 400-metrerunning track, the 100 m is held on the home straight, with the start usually being set on an extension to make it a straight-line race. There are three instructions given to the runners immediately before and at the beginning of the race: "on your marks", "set", and the firing of the starter's pistol. The runners move to the starting blocks when they hear the 'on your marks' instruction. The following instruction, to adopt the 'set' position, allows them to adopt a more efficient starting posture and isometrically preload their muscles: this will help them to start faster. A race-official then fires the starter's pistol to signal the race beginning and the sprinters stride forwards from the blocks. Sprinters typically reach top speed after somewhere between 50 and 60 m. Their speed then slows towards the finish line.
The 10-second barrier has historically been a barometer of fast men's performances, while the best female sprinters take eleven seconds or less to complete the race. The men's world record is 9.58 seconds, set by Jamaica's Usain Bolt in 2009, while the women's world record is 10.49 seconds, set by American Florence Griffith-Joyner in 1988.[a]
The unofficial "world's fastest man or woman" title typically goes to the Olympic or World 100 metres champion.[3][4][5]
The 200 metre time almost always yields a "faster" average speed than a 100-metre race time, since the initial slow speed at the start is spread out over the longer distance.[6] The current men's Olympic and world champion is Noah Lyles, while the current women's Olympic champion is Julien Alfred, and the world champion is Sha'Carri Richardson.
Race dynamics
Start
At the start, some athletes play psychological games such as trying to be last to the starting blocks.[7][8][9]
At high level meets, the time between the gun and first kick against the starting block is measured electronically, via sensors built in the gun and the blocks. A reaction time less than 0.100 s is considered a false start. This time interval accounts for the sum of the time it takes for the sound of the starter's pistol to reach the runners' ears, and the time they take to react to it.
For many years a sprinter was disqualified if responsible for two false starts individually. However, this rule allowed some major races to be restarted so many times that the sprinters started to lose focus. The next iteration of the rule, introduced in February 2003, meant that one false start was allowed among the field, but anyone responsible for a subsequent false start was disqualified.
This rule led to some sprinters deliberately false-starting to gain a psychological advantage: an individual with a slower reaction time might false-start, forcing the faster starters to wait and be sure of hearing the gun for the subsequent start, thereby losing some of their advantage. To avoid such abuse and to improve spectator enjoyment, the IAAF implemented a further change in the 2010 season – a false starting athlete now receives immediate disqualification.[10] This proposal was met with objections when first raised in 2005, on the grounds that it would not leave any room for innocent mistakes. Justin Gatlin commented, "Just a flinch or a leg cramp could cost you a year's worth of work."[11] The rule had a dramatic impact at the 2011 World Championships, when current world record holder Usain Bolt was disqualified.[12][13]
Mid-race
Runners usually reach their top speed just past the halfway point of the race and progressively decelerate to the finish. Maintaining that top speed for as long as possible is a primary focus of training for the 100 m.[14]Pacing and running tactics do not play a significant role in the 100 m, as success in the event depends more on pure athletic qualities and technique.
Finish
The winner, by IAAF Competition Rules, is determined by the first athlete with their torso (not including limbs, head, or neck) over the nearer edge of the finish line.[15] There is therefore no requirement for the entire body to cross the finish line. When the placing of the athletes is not obvious, a photo finish is used to distinguish which runner was first to cross the line.
Climatic conditions, in particular air resistance, can affect performances in the 100 m. A strong head wind is very detrimental to performance, while a tail wind can improve performances significantly. For this reason, a maximum tail wind of 2.0 metres per second (4.5 mph) is allowed for a 100 m performance to be considered eligible for records, or "wind legal".
Furthermore, sprint athletes perform a better run at high altitudes because of the thinner air, which provides less air resistance. In theory, the thinner air would also make breathing slightly more difficult (due to the partial pressure of oxygen being lower), but this difference is negligible for sprint distances where all the oxygen needed for the short dash is already in the muscles and bloodstream when the race starts. While there are no limitations on altitude, performances made at altitudes greater than 1000 m above sea level are marked with an "A".[16]
The 10-second mark had been widely considered a barrier for the 100 metres in men's sprinting. The first man to break the 10 second barrier with automatic timing was Jim Hines at the 1968 Summer Olympics. Since then, over 190 sprinters have run faster than 10 seconds. Similarly, 11 seconds is considered the standard for female athletes. The first woman to go under 11 seconds was Marlies Göhr in 1977.
Record performances
Major 100 m races, such as at the Olympic Games, attract much attention, particularly when the world record is thought to be within reach.
The men's world record has been improved upon twelve times since electronic timing became mandatory in 1977.[17] The current men's world record of 9.58 s is held by Usain Bolt of Jamaica, set at the 2009 World Athletics Championships final in Berlin, Germany on 16 August 2009, breaking his own previous world record by 0.11 s.[18] The current women's world record of 10.49 s was set by Florence Griffith-Joyner of the US, at the 1988 United States Olympic Trials in Indianapolis, Indiana, on 16 July 1988[19] breaking Evelyn Ashford's four-year-old world record by 0.27 seconds. The extraordinary nature of this result and those of several other sprinters in this race raised the possibility of a technical malfunction with the wind gauge which read at 0.0 m/s – a reading which was at complete odds to the windy conditions on the day with high wind speeds being recorded in all other sprints before and after this race as well as the parallel long jump runway at the time of the Griffith-Joyner performance. The next best wind legal performance is Elaine Thompson-Herah's 10.54 second clocking in 2021 at the Prefontaine Classic. Griffith-Joyner's next best legal performance of 10.61 from 1988, would have her third on the all-time list behind Thompson-Herah and Shelly-Ann Fraser-Pryce (10.60).[20]
Some records have been marred by prohibited drug use – in particular, the scandal at the 1988 Summer Olympics when the winner, Canadian Ben Johnson was stripped of his medal and world record.
Any performance with a following wind of more than 2.0 metres per second is not counted for record purposes. Below is a list of wind-assisted times (equal or superior to 9.80). Only times that are superior to legal bests are shown:
Andre De Grasse (CAN) ran 9.69 (+4.8 m/s) during the Diamond League in Stockholm on 18 June 2017,[60] 9.74 (+2.9 m/s) during the Diamond League in Eugene, Oregon on 21 August 2021, and 9.75 (+2.7 m/s) during the NCAA Outdoor Track and Field Championships in Eugene, Oregon on 12 June 2015.
Carl Lewis (USA) ran 9.78 (+5.2 m/s) during the U.S. Olympic Trials in Indianapolis, Indiana on 16 July 1988 and 9.80 (+4.3 m/s) during the World Championships in Tokyo on 24 August 1991.
Tim Montgomery ran 9.78 (+2.0 m/s) in Paris on 14 September 2002, which was at the time ratified as a world record.[62] However, the record was rescinded in December 2005 following his indictment in the BALCO scandal on drug use and drug trafficking charges.[63] The time had stood as the world record until Asafa Powell first ran 9.77.[64]
Ben Johnson ran 9.79 (+1.1 m/s) at the Olympics in Seoul on 24 September 1988, but he was disqualified after he tested positive for stanozolol after the race. He subsequently admitted to drug use between 1981 and 1988, and his time of 9.83 (+1.0 m/s) at the World Championships in Rome on 30 August 1987 was rescinded.
Any performance with a following wind of more than 2.0 metres per second is not counted for record purposes. Below is a list of wind-assisted times (equal or superior to 10.75). Only times that are superior to legal bests are shown:
Brittany Brown (USA) ran 10.66 (+3.2 m/s) during the Michael Johnson Invitational in Waco, Texas on 24 April 2022.
Melissa Jefferson (USA) ran 10.69 (+2.9 m/s) during the USA Outdoor Track and Field Championships in Eugene, Oregon on 24 June 2022.
Tori Bowie (USA) ran 10.72 (+3.2 m/s) during the USA Outdoor Track and Field Championships in Eugene, Oregon on 26 June 2015 and 10.74 (+3.1 m/s) during the U.S. Olympic Trials in Eugene, Oregon on 3 July 2016.
Sha'Carri Richardson ran 10.64 (+2.6 m/s) at the US Olympic trials in Eugene, Oregon on 19 June 2021, but her result was later nullified due to a positive test for cannabis.
Trayvon Bromell recorded the fastest wind-assisted (+4.2 m/s) time for a junior or age-18 athlete of 9.77 seconds on 18 May 2014 (age 18 years, 312 days).[119]
Yoshihide Kiryu's time of 10.01 seconds matched the junior world record set by Darrel Brown and Jeff Demps, but was not ratified because of the type of wind gauge used.[120]
British sprinter Mark Lewis-Francis recorded a time of 9.97 seconds on 4 August 2001 (age 18 years, 334 days), but the wind gauge malfunctioned.[121]
Nigerian sprinter Davidson Ezinwa recorded a time of 10.05 seconds on 4 January 1990 (age 18 years, 43 days), but with no wind gauge.[122]
Below is a list of all other legal times equal or superior to 10.06:
Briana Williams ran 10.94 s at the Jamaican Championships on 21 June 2019, which would have made her the fourth fastest junior female of all time.[138] However, she tested positive for the banned diuretic hydrochlorothiazide during the competition. She was determined to be not at fault and received no period of ineligibility to compete, but her results from the Jamaican Championships were nullified.[139][140][141]
Below is a list of all other legal times equal or superior to 11.10:
Briana Williams ran 10.94 s at the Jamaican Championships on 21 June 2019, which would have been a world under-18 best time.[138] However, she tested positive for the banned diuretic hydrochlorothiazide during the competition. She was determined to be not at fault and received no period of ineligibility to compete, but her results from the Jamaican Championships were nullified.[139][140][141]
Below is a list of all other legal times equal or superior to 11.24:
Briana Williams also ran 11.10 (2019), 11.11 (2019), 11.13 (2018), 11.21 (2018).
The best performances by 5- to 19-year-old athletes are also recorded by Dominique Eisold, exclusively considering performances from 60 countries.[159][160]
^It is widely believed that the anemometer was faulty for the race in which Florence Griffith-Joyner set the official world record for the women's 100 m of 10.49 s.[1] A 1995 report commissioned by the IAAF estimated the true wind speed was between +5.0 m/s and +7.0 m/s, rather than the 0.0 recorded.[1] If this time, recorded in the quarter-final of the 1988 U.S. Olympic trials, were excluded, the world record would be 10.54 s, recorded by Elaine Thompson-Herah at the 2021 Prefontaine meet in Eugene on 21 August 2021.[1][2]
^by World Athletics source; 30 October 2022 by OAA source
^Linthorne, N.(PHD)(1995)The 100m World Record by Florence Griffith Joyner at the 1988 U.S Olympic Trials. Report for the International Amateur Athletic Federation Department of Physics, University of Western Australia
^"Women's 100m T12 Results"(PDF). Rio 2016 official website. 9 September 2016. Archived from the original(PDF) on 21 September 2016. Retrieved 14 September 2016.
The IOC did not initially decide to regrade the results, as silver medalist Ekaterini Thanou had herself been subsequently involved in a doping scandal in the run-up to the 2004 Summer Olympics. After two years of deliberation, in late 2009 the IOC decided to upgrade Lawrence and Ottey to silver and bronze respectively, and leave Thanou as a silver medallist, with the gold medal withheld.