I’m swimming around a circuit of buoys in Lough Dan, County Wicklow, on an icy day in early February. The cold is creeping up my fingers, into my hands and up my arms, gradually numbing them. There’s a little voice in my head saying, “Stop.” But there’s another voice that says, “Keep going, you can do this.”

I keep going.

I am determined to do all four laps of the 400-metre circuit: an Ice Mile.

Ice swimming is swimming in water below 5 degrees Celsius wearing only one swim hat and one swimsuit. You can’t train for this in a 29-degree swimming pool. I had to do a 1km ice swim to qualify. I swim in the sea in Bray, County Wicklow, most weeks, but at around 7 degrees in winter, it is a little too warm.

To clock up my ice swims I have been travelling regularly to Wild Water in Armagh. Their 25-metre natural outdoor pool is reliably cold in winter and is the ideal place to train in a controlled environment. However, there is no controlling the temperature. After getting through my first two swims at just under 3 degrees I arrived for my 1km qualifying swim to see the owner, Ian Conroy, breaking the ice on the pool. At 1.7 degrees, the water was the coldest I had ever experienced. I managed half a kilometre before deciding it was wiser to hit the sauna!

There’s no sauna on the shores of Lough Dan, and very little shelter. The day of my Ice Mile is not only cold but also windy. The extra challenge of choppy water is unnerving, and it is hard to settle into the swim. My tow float is blowing around and I ditch it before setting off for the second lap. By now I’m angry with the water, and this helps me attack the swim. There is a time limit of 45 minutes for the swim, and if I do not keep the pace up I will be pulled out.

By the third lap I’m feeling good. The water is 4.4 degrees. After the frozen water in Armagh, this actually feels like my comfort zone. Still, the finish is a tough slog. I try to pick up the pace but I have slowed to a crawl. Two marshals are standing knee-deep in the water urging me on. I reach them, and they pick me up and walk me ashore.

Despite the agony, I am delighted. It is two years since I set myself this goal, and now I have done it. As a swimming coach, my job is helping people achieve things that were impossible for them – their first length of the pool, their first kilometre. I set impossible goals for myself too: my first marathon, my first 10km swim, my first ironman race.

There is an unexpected bonus to this achievement. During my training I realised that no Irish woman had done both an Ironman and an Ice Mile, although I never intended to set a record.

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