The Siberian Yenisei is the largest river system that flows into the Arctic Ocean. My nine-year-old daughter Nastya and I are swinging our arms and jumping around to warm up before we go into the water.

The activity of a hydroelectric dam upstream means the Yenisei doesn’t usually freeze along the 120-mile stretch that flows through the city of Krasnoyarsk. But the water temperature is just above 0C, so it really is ice water. At the Megapolis swimming club, which is where we are in this picture, ice has formed along the shore because air temperatures have reached -40C this winter. The club cuts a hole in the ice with an axe or chainsaw each time we swim.

People who swim in ice water are called “walruses” in Russia. I’ve been doing this for nine years. Nastya tried it for the first time when she was two; I took her in my arms as I went into the river. At first she didn’t like it, and I didn’t force her: I wanted her to come to this on her own. When she was four she tried it again and understood that it was a good thing. We swim in cold water because it’s good for your health. It gives you a shot of energy and puts you in a good mood. For me, it’s a necessity, an addiction. After you do it a few times, your body wants to continue. It’s like a drug, but only positive.

It strengthens your immune system. Nastya gets sick less often than other children her age. She’s less vulnerable to colds, and when she comes down with a virus she recovers more quickly: she’ll be back to school in a week, whereas other kids will be out for two weeks or more. Nastya is the only walrus in her class; the other children are intrigued when she shows them photographs and videos.

We go two to three times a week, year-round. Even in the summer, the water temperature doesn’t get above 12.2C. We usually submerge ourselves for 30 seconds or more, going in several times. Last weekend the air temperature was -26.7C, which is the coldest weather Nastya has swum in. I once competed in a race when it was -35C outside.

I enjoy the social aspect of cold water swimming, too. We go to Megapolis on Saturdays, but otherwise we go to the Cryophile winter swimming club, which is also on the Yenisei and is named after organisms that live in extremely cold temperatures. After we go in the water, we warm up and socialise in the wood-fired banya – it’s like a steam room – in the clubhouse.

We also see friends at events like the World Winter Swimming Championships, which Russia is hosting for the first time in March, in Tyumen. They usually cut an eight-lane swimming pool in the ice. Nastya will compete for the first time. She’s still small and can’t be in the water for too long, so she will participate in the 25m competition.

I’ll compete in the 100m, 200m and 450m, which is the marathon of winter swimming. It’s six to 12 minutes in cold water, which is a serious test for the body. I won first place in my age group 450m in Jurmala, in Latvia, in 2012. I want to prove that it wasn’t a fluke.

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