Timing commences either automatically upon the start gun being triggered or from the first sight of light from the starting gun and concludes with the athlete’s torso (not head, arms or legs) crossing the finish line.
Athletes start in a straight line across the track for 50m, 70m and 100m runs, and on a stagger for 200m and 400m runs. In all these distances, athletes must stay in their lanes. For the 800m, athletes will have a staggered start and must remain in their lanes until the merging point as explained by the starting official(s).
Athletes start on a curved line for 300m, 500m, 700m and 1500m runs and may run in any lane after the start.