The 300 metres is another informal distance, which could be used to aid a 200m runner's stamina, or a 400m runner's speed. Currently the world's best for this event is 30.81 seconds, set by Wayde van Niekerk in Ostrava, Czech Republic in 2017.[14] The women's record is 35.30 seconds, set by Ana Guevara at altitude in Mexico City in 2003. Junior girls in several countries run this distance instead of the 400 metres.