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.
Okayama International Circuit (岡山国際サーキット), formerly known as TI Circuit Aida (TIサーキット英田) before 2005, is a 3.703 km (2.301 mi) private motorsport race track in Mimasaka, Okayama Prefecture, Japan. TI was the abbreviation of "Tanaka International" after the name of the golf club owner, Hajime Tanaka, though the name of the circuit was officially "TI Circuit Aida".
The 4 × 100 metres relay or sprint relay is an athletics track event run in lanes over one lap of the track with four runners completing 100 metres each. The first runners must begin in the same stagger as for the individual 400 m race. Each runner carries a relay baton. Before 2018, the baton had to be passed within a 20 m changeover box, preceded by a 10-metre acceleration zone. With a rule change effective November 1, 2017, that zone was modified to include the acceleration zone as part of the passing zone, making the entire zone 30 metres in length. The outgoing runner cannot touch the baton until it has entered the zone, and the incoming runner cannot touch it after it has left the zone. The zone is usually marked in yellow, frequently using lines, triangles or chevrons. While the rule book specifies the exact positioning of the marks, the colours and style are only "recommended". While most legacy tracks will still have the older markings, the rule change still uses existing marks. Not all governing body jurisdictions have adopted the rule change.
The 3000 metres or 3000-metre run is a track running event, also commonly known as the "3K" or "3K run", where 7.5 laps are run around an outdoor 400 m track, or 15 laps around a 200 m indoor track.
The NACAC U18 Championships in Athletics is an bi-annual championships to athletes under-18 years of age in the year of competition held between the member associations of the North American, Central American and Caribbean Athletic Association (NACAC). The inaugural edition took place in 2019 in Queretaro, Mexico.
