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IISA ratified ice miles


What is an IISA ratified ice mile, exactly?

From the IISA rule book:

The spirit of the Ice Mile was never created for competition purposes but as an individual challenge with the spirit of extreme adventure. Ice Miles can be attempted in any Icy place on earth as long as it adheres in full to IISA Rules. Extreme challenges always come with extreme planning, training and safety. IISA Swimming and Safety Rules are there to set the minimum requirements for an Ice Mile in safe, assessable and hazard free location. It is with the Swimmer and his or her safety and logistics team to increase and improve on the safety requirements as location and conditions extends to the extreme.

Rules of the swim:

Here's a basic run-down of some of the IISA's parameters for ratification, but always consult the rule book for more details and the most up-to-date rules and information:

  • ECG must be done within 6 months of the swim, along with a medical assessment done by a medical doctor;
  • An Observer and Witness to the swim are required, as well as medical support if emergency services are far from venue (new rule);
  • A qualifying swim done beforehand is required;
  • Official distance = 1 British mile (16.09km)
  • Water temperature must be 5.0 (five with one decimals) degrees Celsius (“C”) or below or 41.0 degrees Fahrenheit (“F”), measured as follows: 

    • ​For a continuous period of at least 5 (five) minutes, at a depth of between 5 (five) to 20 (twenty) inches below the water surface;

    • Temperature must be established by using the average reading obtained from 3 (three) digital thermometer readings with a temperature accuracy of +/-1.0C (at least one decimal display);

    • To be valid for the purposes of an Ice Swim, all three thermometers must register 5.0C or below;

    • The thermometers must be water submerged thermometers or utilise a probe; no laser or infra-red thermometers are allowed;

    • The official water temperature must be measured no more than 30 minutes before the Swim begins;

    • If water temperature is close to or at 5.0C, the Observer is required to take several measurements across the course and during the Swim to ensure average water temperatures remain at 5.0C or less for the duration of the Swim;

    • Use of watches, or watch-type devices, for distance and temperature measurement are not allowed.

  • Only standard swim items can be worn - bathing suit no lower than knees, 1 swim cap latex or silicon, approved goggles, earplugs, swim float or safety belt, lubrication for chafing, but NO neoprene, NO MP3 players, NO heat sources.

  • There are also specific video and photographic requirements for documenting the swim.

Training for the mile

Training for the swim is everything, you may think you can muscle through it or wish and will yourself to the finish, but in water that cold, it's a really risky approach. Chances are, you won't actually succeed anyhow if you aren't physically and mentally prepared. Sorry, but I need to be blunt and firm on this point - don't be an idiot. It's not worth it. Train, train, train.


I started with the following general rule of thumb: know what you're getting into before you attempt it. I think it's a pretty risk thing to attempt an ice mile in your first season of cold water swimming. If you've never even been in sub 5C water before ever, and have no idea how it will affect your body during or after the swim, a mile is probably not the place to try it out. I had my eye on an ice mile for some time, mulling it over in the back of my head for years before I was really ready for it. Everyone is different, and it depends on your availability and dedication to training, but understand that it's a huge risk to your well being to attempt this swim without knowing what it means to spend time in water that cold.

There were 4 things I did to train for my first season of ice miles, which I will continue to use, and I think they helped me both succeed in finishing but more importantly, stay safe both during and after the swim:

  • I used the IISA's qualifying time/distance chart as a basis for my training plan, but I also reached above it. So as an example, at water temp between 10-11C, the minimum distance for a qualifying swim is 3,500m. I did more than that, 4,000m+. I actually started this approach as soon as the water started cooling in the fall, and swam as long as I possibly could each time I got in the water. As a result, I was acclimating above IISA requirements if my swims had been qualifying swims. By the time I got down to sub 5C water, it was just another swim in a series of long training swims, and I had exposed myself as much as possible while riding the temperature down.

  • I swam as often as I could, my schedule only permitted once or twice a week but that worked for me. I just tried to fit in as much as I could before swimming the mile, especially the very first one.

  • Because I swam long and swam often, I trained the recovery as much as I trained the mile itself. I was cold, went through after-drop again and again, making sure I knew what it felt like. The recovery is a dangerous part of the swim, as cool blood starts to recirculate through your body, your core temperature drops even further down than during the swim. Sometimes it was miserable, but doing this helped improve my acclimatization, and it also meant there were no surprises when I was done the mile itself. It was still the coldest I've ever been and the roughest recovery I'd been through, but I knew what to expect and I knew I was ok.

  • I practiced the swim itself beforehand. The entry, the route, the exit. I knew the area well as we were training there regularly, and it gave me a chance to check out every aspect of the swim. I felt confident, and there were no surprises.

How did I know when I was ready?

I didn't. Don't get me wrong, I knew I had trained well and was confident in my preparation. But I made a point of putting my ego aside before starting the swim. At the safety briefing, I was clear that (a) I would not be risking my safety and I'd get out if I felt at all "off", and (b) the Observer had final say if anyone on the support side felt I needed to be pulled. A swimmer cannot contest being pulled, the Observer is in charge. And I knew I needed to trust the support crew, they would see things I couldn't. Warnings would be treated as warnings, not challenges for me to muscle through. I knew it was possible that I might not finish, and I accepted this before even stepping foot in the water. I was still motivated and driven, but felt even more empowered knowing I was not willing to put myself at any additional risk. I felt in control, but I let the swim and my body dictate whether I would succeed or not.

Swimming the mile

It was really windy that day, the wind chill was -14C. My approach was to take each lap one at a time and “see how things go”. I spent a lot of time checking in on my body to see how things were doing. My arms and hands got chilly right away because of the wind, but I was able to keep moving my hands and fingers, I had been worried they would freeze. I forgot to kick, even just a little, and didn't realize it until I noticed how cold my legs were. The most important thing, I just stayed focused and controlled, constantly checking myself for any warning signs. I didn't stress about the swim, I just calmly went about doing what I had trained for.

I sometimes get questions from swimmers who are thinking of doing an ice mile, and thought it might be a good idea to document some of the considerations and practices I used when preparing for mine.


When I think back on it, I laugh a little because doing ice miles was not something I ever thought I'd get serious about when I first started cold water swimming. I remember talking about it with fellow swim friends into our first season of swimming cold, but by the time we got down to 5C for the first time, we all exclaimed the same thing - are you kidding me, it's SO cold!!!

And then a few years later, there I was, swimming my first ice mile, proud that I'd come so far in my training. I also became the first Canadian woman to be complete the swim and be ratified by the International Ice Swimming Association (IISA). I had trained hard, and in the weeks that followed, I undertook more swims...

       (first Canadian woman to complete an ice mile, placed 9th in top 10 records for longest worlds women distance 2018 - present)

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