When the national swimming team took ground in Rome on Monday, the thermometer showed 37 degrees.
On Tuesday it was a little cooler - "only" 32 degrees - and in the afternoon a warm thunderstorm.
But the forecasts for the coming days speak of temperatures of over 30 degrees and lots of sun.
The swimmers are used to competing indoors, but in Rome it is outdoors at the Foro Italico in the same pool used in the 1960 Olympics.
It is the first time a major championship is swimming outdoors since the 2009 WC in Rome.
- I have never been part of it, says the medalist in the 100 meter butterfly, Louise Hansson, 25 years old.
"The Great Challenge"
What will be the most important thing?
- Mainly to drink and stay in the shade.
It is probably the days before you can sit outside for a few minutes, but for the next few days it is important to stay in the shade and try to keep the fluid balance.
That is the big challenge, says Louise Hansson.
There have been rumors that the organizers will put up some temporary roof, sailcloth or similar, over the pool, but Swedish press manager Anna Hammar says that they have so far been met with evasive answers when they have asked.
However, the Swedish national team has prepared properly, both with meetings on the issue and extra equipment, says national team doctor Charlotte Wallin.
The national swimming team has received support from the Swedish Olympic Committee (SOK) and is using their preparations for the Olympics in Tokyo.
- Even in terms of equipment, we have borrowed cooling vests, collars that you fill with cooling elements, then we have towels that you dip in cold water for a cooling effect, says Wallin and demonstrates a saliva meter connected to an app that is used to continuously keep track of the swimmers' fluid levels.
"Five-six liters per day"
Filling up on fluids and staying out of the sun will be important.
- For ordinary people at home in Sweden, it is a couple of liters of water per day that applies and this increases manifold when you are out in the heat and doing physical activity.
It can be a need that is up to five to six liters per day, but it is very individual, says Wallin and continues:
- We have a good recovery area in the stadium with a roof and large fans, we have brought extra fans from Sweden, so that we have the best possible environment.
- Of course, it is important to limit the time outdoors, that is the most important thing, and plan your races and your days, not to hang out in the heat unnecessarily.
CLIP: Victor Johansson on the relationship with Nils van der Poel (6 Aug 2022)
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Victor Johansson has spoken to Nils van der Poel about training.
Photo: Bildbyrån/SVT