200 m

Half a lap, all of it in lanes. The stagger puts the outside runners ahead at the gun so that everyone covers the same distance. The race starts on the bend, where the lean into the curve costs a little speed, and ends on the home straight, where holding form through the last fifty metres decides it. Blocks, fully automatic timing and the 0.100-second false-start rule all apply, as in the 100 metres. The wind gauge reads on the straight for ten seconds; above 2.0 metres per second of tailwind the time is wind-aided and does not count for records.