How Cold is an Olympic Swim Pool?

Pool temperature is a crucial factor in keeping the water comfortable for participation in swimming events and training.

While there are plenty of pool shapes and temperatures, from the moderately warm hotel pool to the local lap pool, there are very strict temperature guidelines when it comes to Olympic swimming pools.

According to World Aquatics, the international governing body for competitive swimming, the temperature of Olympic swimming pools must be between 25 and 28°C (or 77°F and 82.4°F).

National governing bodies such as USA Swimming, Swimming Natation Canada, Australian Swimming, British Swimming, and others follow the international governing body when dictating pool temperature for swim competitions.

In this article, we will examine why Olympic swimming pools are kept at this specific temperature, the temperatures of other types of swim pools, and the pool temperatures of Olympic swimming pools of the past.

Let’s dive in!

Why Are Olympic Swimming Pools so Cold?

Olympic swimming pools are kept cool to allow athletes to exert themselves without worrying about overheating and discomfort.

Whether during competitions or long, exhaustive bouts of swim training, which regularly last 90-120 minutes (or even longer), colder pool temperatures allow swimmers to swim in comfort for longer.

A colder pool temperature also:

Helps swimmers regulate temperature.

When swimming intensely, either during an extended swimming race (the longest pool race in the Olympics is the 1500m freestyle, around 14-16 minutes of pure effort) or during swim training, cooler pool water helps swimmers better regulate body temperature.

When swimming all-out, the body generates a significant amount of heat, especially when you consider that swimmers often wear heat-trapping swimming caps made of silicone when training and competing.

The colder water in Olympic swimming pools helps swimmers dissipate heat more efficiently.

Reduced dehydration.

Olympic swimming pools use a temperature that reduces the performance-crashing effects of dehydration, which can start when athletes are dehydrated by as little as 2% of total body weight (Jeukendrup and Gleeson, 2020).

A study with competitive swimmers, titled “Effects of three different water temperatures on dehydration in competitive swimmers,” looked at the sweat rates and hydration levels after a 5km time trial swum under different pool temperatures.

Perhaps unsurprisingly, when the swimmers were tested after the warmest pool temperature, a balmy 32-degrees Celsius, dehydration and sweat rates were highest compared to temperatures of 23°C and 27°C.

Faster swimming.

A consistent and slightly cool water temperature in Olympic pools can promote faster swimming.

In the above-mentioned study, the fastest 5km time trials were performed at 27°C, which is right at the temperature Olympic swim pools are set.

Interestingly, another study published in the Journal of Sports Medicine and Physical Fitness (Mougios and Deligiannis, 1993) with competitive swimmers found that short, maximum-effort swims (covering 100m) benefit from a warmer pool temperature (32°C) compared to pool temperatures of 20 and 26°C.

The warmer pool temperature also generated the highest peak heart rate and lactate levels.

This matches the anecdotal experience of swimmers and exemplifies the “Goldilocks” principle with Olympic pool water temperature.

When the water is too cold, our muscles constrict, making it difficult to swim comfortably and with full effort.

When it’s too warm, swimmers struggle to regulate excess heat, expend more energy, and tire faster.

Ultimately, Olympic swimming pool temperatures attempt to balance comfort and performance, giving swimmers the best chance to go fast.

History of Olympic Swimming Pool Temperatures

Here are some sample pool temperatures of recent Olympic Games swimming events:

  • The swimming events at the 1996 Atlanta Olympics were held at Georgia Tech University. The pool temperature was held at 78-80 degrees Fahrenheit.
  • The Beijing Olympics in 2008, when Michael Phelps won 8 gold medals in the pool, were held in the Water Cube, with the pool temperature a steady 28-degrees Celsius.
  • The London Aquatics Centre, site of the 2012 London Olympics, maintained a pool temperature of 27 degrees Celsius.

What is the temperature of the water for Olympic open water swimming events?

During the first three Olympic Games, swimming races were all open water races, being held in natural bodies of water like rivers and lakes.

Open water races returned to the Olympic swimming program at the Beijing Olympics in 2008.

The variance in water temperature with marathon swimming events is wider given the nature of the elements. Water temperature is required to be within the range of 16 and 31 degrees celsius.

According to the rules set forth in FINA’s Open Water Swimming Manual (2020), the temperature of the water is measured in the middle of the course approximately two hours before the beginning of the race.

A Safety Officer is also required to be on site during the competition, measuring and recording the water temperature at regular intervals along the race course.

What temperature are NCAA swimming pools?

Pools for NCAA competitions are kept at nearly an identical temperature as Olympic swimming pools.

According to Article 12 of the NCAA Swimming & Diving Rulebook, pool temperature is required to be between 26 and 27 degrees Celsius (79 to 81 degrees Fahrenheit).

The NCAA also recommended an air temperature of no more than four degrees less than the water temperature. Air temperature is measured at deck level.

Diving tanks separate from the main swimming tank can be kept at a temperature between 28 and 30-degrees Celsius.

How warm should a pool be for swim lessons?

Warmer pool temperatures allow newer swimmers to be more comfortable during learn-to-swim programs.

According to the American Red Cross, the water for preschool swim lessons should be no warmer than 32 degrees.

For junior learn-to-swim and lifeguard lessons, the pool temperature should be no warmer than 29 degrees. For “intense” swimming activity, the water temperature should be 26-28 degrees.

Wrapping Things Up

The temperature of Olympic swim pools and other competitive swim venues allows swimmers to perform comfortably.

The regulations of Olympic swim pools ensure consistency and fairness, with temperatures ranging between 25-28 degrees Celsius (77 to 82 degrees Fahrenheit).

This temperature range promotes efficient heat dissipation, muscle function, and general comfort during swim meets and training.

By striking a balance between cool water and warm bodies, swimming pools worldwide allow swimmers to push their limits on our sport’s biggest stages.

See also: How Big is an Olympic-Sized Swimming Pool?


Olivier Poirier-Leroy is a former national-level swimmer, author, swim coach, and certified personal trainer. He’s the author of the best-selling books YourSwimBook and Conquer the Pool

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7 days ago

How much faster could Beijing have been with a colder pool?

1 month ago

Olympic pool was 71 in 1952

1 month ago

A cool pool is a fast pool.

About Olivier Poirier-Leroy

Olivier Poirier-Leroy

Olivier Poirier-Leroy is a former national-level swimmer, swim coach, and best-selling author. His writing has been featured on USA Swimming, US Masters Swimming, NBC Sports Universal, the Olympic Channel, and much more. He has been involved in competitive swimming for most of his life. Starting off at the age of 6 …

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