This article is part of the Masters Swimming 101 series

Coaches will give instructions mainly in terms of distance (or yardage) and time. Most American pools are 25 yards in length and are known as short course yards pools or SCY. To understand the sets, you'll need to add in multiples of 25.

50 yards = 2 lengths of a 25-yard pool

100 yards = 4 lengths of a 25-yard pool

200 yards = 8 lengths of a 25-yard pool

500 yards = 20 lengths of a 25-yard pool

Olympic-sized

If the pool is 50 meters, you'll know it. These courses are also called long course meters or LCM. Now you'll add in multiples of 50.

50 meters = 1 length of a 50-meter pool

100 meters = 2 lengths of a 50-meter pool

200 meters = 4 lengths of a 50-meter pool

400 meters = 8 lengths of a 50-meter pool

Usually, the American system of yards prevails during the school year, and the international system of meters prevails during the summer. A third distance, 25 meters, also known as short course meters or SCM, is the least common. For pools that are set up for 25 meters, SCM meets usually occur in the winter. 

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