When I swim Great Bear this year I will be following traditional marathon swim rules. This means I can wear no more than a swimsuit, cap and googles; in other words – no wetsuit. The water is currently somewhere between ten and 14 Celsius and the air temperature will likely be similar. The possibility of hypothermia is a safety risk that is to be taken seriously.
There are two things I do to manage the risk; the first is train for cold water and the second is for my safety crew to be fully prepared should it happen.
Training for cold water
I have been open water swimming for about 8 years and ocean swimming for 6. When I first started ocean swimming I used a wetsuit. Over time I became comfortable skin-swimming (wetsuit free) and over time I developed a layer of brown fat – a type of fat that helps better insulate my body from the cold.
This year, because the swims I am doing are a wee bit colder I increased my cold water conditioning by spending time in the ocean at various points throughout the winter. At times I was swimming in 3C water. The swims were short, but the hope is they did what they needed to do in terms of increasing my brown fat. I remember one day I went in, it was so cold my water thermometer stopped working and my body went into such a primal panic that I was out in about 7 minutes.
More recently I have been swimming in waters averaging 10C for 1 to 2 hour periods. I use this time to condition myself mentally. Although my preference when swimming is cooler waters to help manage my Multiple Sclerosis while exercising, 10C can be pretty darn uncomfortable. My body burns for the first 20 to 30 minutes until it goes numb, and then I just feel cold. I loose feeling in my hands and feet as all of my blood rushes toward the core of my body to protect my organs.
Hopefully I have done a good job of preparing and will be able to remain in the water for up to 8 hours a day. In the event that I cannot withstand the cold my crew will be prepared.
In the event of hypothermia
There is really no such thing as a solo swim when you are swimming distances like this. Although I am the only swimmer, I have a full crew who are trained to make sure I am safe in the environment and know how to monitor my swimming for signs of distress.
To monitor for hypothermia, every 30 minutes my crew checks how many swim strokes I take each minute. If there is a significant decline it is a sign I am in distress. They are also monitoring the color of my skin – if it becomes to white it may be a sign that my blood is not circulating as it should. In addition every half-an-hour when I stop to feed they will look to see if I am shivering and they will have a conversation with me to see if my speech has changed and if I am coherent. They may have a bit of a math test for me to make certain.
If hypothermia is confirmed, my crew will remove me from the water and begin treatment.
Huge shout out and thank you to Helly Hansen for providing a fabulous bag for my hypothermia kit. It is important to me that my crew has everything they need in one place in a dry space. My swims are self-funded so having contributions like this go a long way.
Here’s what the kit’s made of:
- HH Duffel Bag (50L)
- 2 big towels
- 1 wool blanket
- 1 fleece sleeping sack
- 1 sleeping bag
- 1 toque
- 1 thermometer
In the event that I am pulled from the water for hypothermia I will be stripped down, wrapped in the towels, put in the bags and my toque put on. My crew may add warm water bottles and will monitor my temperature until I am warm enough to come out of my “cocoon” and get dressed.