What Does LCM, SCM and SCY Mean In Swimming? (Explained)

swim timing clock next to pool

In swimming, there are a few common terms that you will hear thrown around. LCM, SCM and SCY are all among these terms. But what do they mean? And why do they matter?

In swimming, LCM stands for Long Course Meters, SCM stands for Short Course Meters, and SCY stands for Short Course Yards. These are all pool lengths used in different types of swimming competitions.

When recording your swim times and trying to compare them to others, the length of the pool you are swimming in will make a big difference. You cannot fairly compare a swim time set in a 50m pool with that set in a 25m pool.

In this article, I want to explain LCM, SCM & SCY, why these terms exist and explain how you can convert your times between LCM, SCM and SCY.

What Does LCM Mean In Swimming?

LCM stands for Long Course Meters. This is the standard pool length used in Olympic swimming competitions. A long course meter pool is 50 meters.

The reason that LCM matters is because it is the standard against which all other pool lengths are measured. When you hear someone say that they swim fast in an LCM pool, this is the pool they are referring to.

What Does SCM Mean In Swimming?

SCM stands for Short Course Meters. This is the standard pool length used in most swimming competitions around the world, with the exception of Olympic swimming competitions. A short course meter pool is 25 meters in length.

The reason that SCM matters is that it offers a different set of challenges and opportunities for swimmers compared to a longer 50m pool.

Because the pool is shorter, it takes less time to swim the same distance in an SCM pool as it does in an LCM pool. The reason for this is that swimmers can kick off the wall every 25m in an SCM pool, giving them a boost.

This can be both good and bad for swimmers. On one hand, it means that they can post faster times in a short course meter pool. On the other hand, it also means they need to have excellent tumble turns and underwater technique, as they will kick off the wall more often.

What Does SCY Mean In Swimming?

SCY stands for Short Course Yards. This is the standard pool length used in most swimming competitions in the United States. A short course yard pool is 25 yards.

The reason that SCY matters and needs to be highlighted is because of the difference in measurement units between pools that are built in meters and those built in yards.

Those swimming in a 25-yard pool will cover less distance than a 25-meter pool, as a 25-yard pool is only 22.8 meters.

As this pool is shorter again, it needs to be noted when recording swim times.

DescriptionPool Length
LCM [Long Course Meters]50 meters
SCM [Short Course Meters]25 meters
SCY [Short Course Yards]25 yards
This table shows the different pool lengths for LCM, SCM & SCY

Is A Pool 25 Yards Or 25 Meters?

A pool can be 25 yards or 25 meters, depending on the region in which it is located.

In the United States, most pools are 25 yards and are referred to as short course yards pools. [SCY]

In most other parts of the world, pools are 25 meters and are referred to as short course meter pools. [SCM]

In the UK, we have some pools that are still in yards as these were built before the UK switched over to the metric system.

The pools I have experienced in the UK which are measured in yards are very old. For example, recently I visited this iconic Victorian pool in Ipswich that was opened in March 1894! [source]

Victorian swimming pool
This Is A Victorian Swimming Pool In The UK

All pools in the UK built since 1965 will be metric, as that is when the UK switched over to the metric system. [source]

When comparing swim times, it is important to distinguish between SCM & SCY, as yards and meters are two different measurements and are not equal. A 25-yard pool is equal to 22.85 meters.

Therefore, if you are trying to record your time in a 25-yard pool, you cannot directly compare it to swimmers who have used a 25-meter pool, as the distances are not equal.

This is why SCM and SCY have been tagged onto swim times as it tells people what length pool you achieved your time.

What Is An Olympic Standard Swimming Pool?

An Olympic standard swimming pool is 50m in length.

The lengths and temperatures of Olympic standard swimming pools are carefully regulated. Not only will the length be exactly 50m, but the pool water temperature is also required to be between 25°-28° Celsius, which is 77°-82.4° Fahrenheit.

This is to ensure that the athletes do not overheat and helps them to perform at their best.

How Do You Convert LCM to SCM to SCY?

If you want to compare your swim times to others but you have swum in a different length pool, it is necessary to account for the different lengths and convert between LCM, SCM or SCY.

1. Swim Time Conversion Calculator

The easiest and quickest way to convert between swim times is to use a Swim Time Conversion Calculator. Here is a link to a swim time conversion calculator from Swimming World Magazine which you can use to convert your swim times from SCY to LCM to SCM. [source]

2. Maths Formula

There is a lot of debate around course conversions because how you convert a yard time to a long course meter time can be argued.

Most national and international swim organizations do not support or recognise course conversions. [source]

If you are qualifying for an event but your swim time has been converted, your time could be placed below swimmers whose times have not been converted.

I have tried to find a simple formula to convert swim times, but the default factor you use seems to depend on what country you are in, what gender you are and what event.

Instead, I have found this PDF that seems simple and readable. This is for Australian swimming.

If you are interested in the maths behind USA swimming, this site may be a better resource.

In general, if you are a competitive swimmer looking for a conversion, I suggest you speak with your coach or official in order to get the correct conversion method for your area and competitions.

If you are just looking to convert your swim times, then using a swim conversion calculator is a great option.

Here are some of my favourite swimming conversion calculators.

Swimming Conversion CalculatorComments
Swim SwamGood to use. Detailed but clear and easy to understand
Team UnifyEasy to use. Points out that not all calculators are accurate.
Swimming World MagazineA major brand, so I would expect this calculator to be discerning and trustworthy.
Alexandria MastersA clean interface. Should be easy to use and follow. Similar in layout to Team Unify.
Omni CalculatorThis is a very comprehensive calculator. A good choice if you are interested in specific strokes.
This table shows a list of swim conversion calculators

Which Is Faster, Short Course Or Long Course?

Short course swimming is faster than long course swimming. This is because when swimmers are in a shorter pool (25m versus 50m) they kick off the wall more often. Kicking off the way increases swim speeds.

When swimming a long course (50m) you are active for much longer. In comparison, when swimming a short course (25m) you get to kick off the wall twice as much, which will increase your speed but also allow your arms to rest.

When swimming in competition, the body is working at full capacity, so any advantage in speed or even minor rest will help swimmers to swim faster.

Below is a list of some of the top swimmers in the world, swimming in the same event, but one is LCM (50m pool) and the other is SCM (25m pool).

Although the time differences might seem very tiny to leisure swimmers, in the world of competitive swimming, a fraction of a second can make the difference between winning a medal and losing out.

Swimmer NameCountryEventSCM TimeSCL TimePercentage Change
Adam PeatyUK100 Breaststroke55.9457.132.12%
Paul BiedermannGermany200 Freestyle1:39.371:42.002.64%
Caeleb DresselUSA100 Butterfly47.7849.453.49%
Sarah SjöströmSweeden50 Freestyle23.0023.672.91%
This table shows swim times for SCM and SCL events

Final Thoughts

Knowing what SCM, LCM, SCY means is important for swimmers because it helps them to understand the distinct challenges and opportunities that each pool length presents.

In order to compare your swim times with someone on the opposite side of the globe who is swimming in a different length pool, you can covert your swim times between LCM, SCM & SCY.

Each pool length has its own set of pros and cons, so it is important for swimmers to be aware of which one they are swimming in.

Knowing the standard pool lengths can help you better compare your times and abilities to other swimmers.

Using a swim conversion calculator is one of the best ways to convert between SCM, LCM and SCY easily, but it is worth checking your result on a range of swim conversion calculators, as there may be a little variation depending on which conversion factor the calculator uses.

What Does ‘SMH’ Mean on TikTok?
What Does ‘SMH’ Mean on TikTok?

Happy swimming!

Louise Byrne

Hi, I am Louise and I am obsessed with swimming. I spend my free time in the water or getting ready for my next water adventure.

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