The swimming relay is a combination of four swimmers in ordered disciplines and in corresponding age category.
Styles for relays:
- Freestyle
- Medley relay (all four styles in order: backstroke, breaststroke, butterfly and freestyle)
Disciplines for relays:
- 4 x 50 (freestyle or medley relay)
- 4 x 100 (freestyle or medley relay)
- 4 x 200 (freestyle)
Sorting by gender:
- Men relay
- Women relay
- Mixed relay (2 men and 2 women in any order)
Age categories:
- Open (no age restrictions)
- Masters (above 25 years old, aggregate relay age 100-119, 120-159, 160-199, …, etc.)
- Seniors (19 + years old)
- Juniors (15-18 years old)
- Kids (according to age 14, 13, 12, …)
Pool length:
- Short pool (25 meters, or in some countries 25 yards)
- Long pool (50 meters, or 50 yards)
Swimmers usually achieve different times in the same discipline according to the pool length.