 The IAAF keeps world records for five different types of track relays . As with 4 × 100 m and 4 × 400 m events , all races comprise teams of four athletes running the same distances , with the less commonly contested distances being the 4 × 200 m , 4 × 800 m and 4 × 1500 m relays . Other events include the distance medley relay ( comprising legs of 1200 m , 400 m , 800 m , and 1600 m ) , which is frequently held in the United States , and a sprint relay , known as the Swedish medley relay , which is popular in Scandinavia and held at the World Youth Championships in Athletics programme . Relay events have significant participation in the United States , where a number of large meetings ( or relay carnivals ) are focused almost exclusively on relay events . 
