How to Train for Colder Marathon Swims

Posted by Scott Zornig, 5 September 2013


If you are a marathon swimmer, chances are you have had to do a swim in water uncomfortably cold. I know many marathon swimmers who did not properly prepare for their marathon swim and became hypothermic. Some of these swimmers ended up being ulled from the water and a few ended up in the hospital. These people obviously did not enjoy their marathon adventure. Let’s face it….it is not a lot of fun when you are cold and miserable. The good news is that anyone can learn to swim in cold water. Swimmers of all weights, heights, shapes and sizes can teach their body to acclimate. Yes, it is true that swimmers who carry a few extra pounds have a “built in” advantage, but anyone can learn to swim in and even enjoy the coldest of waters…..even a swimmer weighing only 105lbs. Proper preparation gives you the best chance of success in a marathon swim.

Here are some tips for preparing for extreme temperatures. The below recommendations come from personal experiences and the training techniques used by others.

  1. Train in the open water year round. The fall season is a perfect time to start cold water acclimation training for a swim the following summer because the water temperature starts off warmer and cools down gradually. This allows your body to ease into cold water swimming.
  2. Do not ever swim in a wetsuit. There is nothing good that comes out of donning a wetsuit when training for a marathon swim.
  3. Avoid training in a heated swimming pool….especially as you get closer to your event. Try to do most of your training in open water which has temperatures similar to your upcoming endeavor. I recommend at least three or four open water swims each week, gradually extending the time that you stay in the water.
  4. Train without a cap. This is one of my preferred methods for cold water training. Save the swim cap for the day of your event.
  5. Train without ear plugs. Once again, save the ear plugs for your marathon swim.
  6. Take cold showers and baths. For the ice baths, try sitting in the tub for 20 minute intervals. Work towards three, 20 minute immersions in an evening. This will get you ready.
  7. Wear light clothing in cooler weather.
  8. Sleep without pajamas and night gowns. Do not use blankets or sheets to cover you. If you really want to be hard core, direct a fan on you as you sleep. It will be difficult at first, but you will eventually get used to it and sleep well.
  9. Do a series of one mile training swims where you exit the water for 15 minutes (and dry off) between each swim. You will understand why this works when you start your 4th or 5th one mile swim.
  10. Find and train in water even colder than the anticipated temperatures of your marathon swim. You should always swim with a thermometer so you know the temperature of the water you are training in.

Unfortunately, not all of us have access to a cold ocean. For example, the SBCSA has had past swimmers from Latin America where the ocean temperature is in the low to mid 80’s Fahrenheit. Swimmers in countries without access to a cold ocean are at a disadvantage when swimming in 50, 60 and 70 degree water. However, they still can execute many of the techniques above. Furthermore, every country has a high elevation lake or a spring fed river which can be used for training. Granted, this may not be as convenient or ideal, but it is an option.

If you prepare properly for your marathon swim, you still need to swim smart on event day. Here are some ways to stay warm during your marathon swim.

  1. Raise your body temperature before starting the swim: My favorite trick is to drink something warm, blast the heat in the car and pile on clothing until I’m uncomfortably hot. This has a short term effect, but can help with the initial minutes of the swim and provide confidence.
  2. Keep moving: Once you start your swim, don’t stop except for fueling your body.
  3. Feedings should be at intervals of 20 or 30 minutes and kept as short as possible. You should be able to complete a feeding in 20 seconds or less.
  4. Do not skip a feeding. Your body needs the fuel. If you miss a feeding, you increase your chances of becoming hypothermic.
  5. Reward yourself by consuming warmed liquids periodically during your swim. I know many swimmers who prefer their energy drinks served warm. Wear a silicone swim cap and ear plugs if the governing association permits it.
  6. Think warm thoughts. The mind is powerful. Use it to your advantage.

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