What is 4x400m?
Relay that usually ends high school/ college track meets. In the 4x400m (also called the 4x4 and 3200m relay), 4 runners each run 400m, or once around the inside lane of an all-weather track. This is considered one of the most exciting relays, as it is still a sprint and the lead can change several times throughout the race. The 4x400 is also one of the most well-known events at the high school (and frequently college) level, which is why it's the final event.
Baylor University is well-known in the track world for sporting a perenial powerhouse in their 4x400m relay.