Cold Water Kayaking Part I: Knowledge is Survival: Hypothermia Cause and Prevention for Kayaker and Adventure Racer

Robert Finlay

Courtsey of Robert Ernest Finlay, Director of Kayak Lake Mead (www.kayaklakemead.com), is a certified instructor by the American Canoe Association. Finlay, 53, graduated  from the US Army Ranger School in 1974, and has a BS from the US Military Academy at West Point, 1976. Finlay’s current occupations include:  an Instructor at Presidio Adventure Racing Academy (climbing and paddling instructor), E-Camp (see www.teamepinephrine.com)  (trekking and paddling instructor), Climbing Guide: Jay Smith’s High and Wild Mountain Guides, Ironworker: Foreman.  Heavy construction, bridges, high rises, etc., and Race Director: Out There Adventures.

This article will give you good working definitions and explanations of hypothermia. It will explain how you can prevent hypothermia, how you can treat hypothermia, AND it will explain what I've learned as an outdoor adventurer, how you can SELF-RECOVER from hypothermia.  

• What is hypothermia:
• "Hypo" means under. "Therm" is a unit of heat. The normal core temperature for you body is 98.6 degrees F. "Core temperature" means the temperature of internal body organs, particularly the heart, brain, lungs, kidneys, stomach, and intestines. 
  
• An abnormally low core temperature is the condition of hypothermia. In this condition normal muscular and mental abilities are impaired. If the condition continues to deteriorate it will lead to death.
  

• What causes hypothermia:
• Hypothermia IS CAUSED by 1) sudden exposure to cold water or CAN BE CAUSED by 2) prolonged exposure to the cold conditions of temperature, water, and wind or by 3) or a very slow and prolonged period of cold conditions AND prolonged fatigue, exhaustion, and lack of food which is not uncommon among adventure racers. In this last case shivering may never be a symptom, but there will be plenty of other signs.
• When heat loss exceeds heat production and heat retention; hypothermia is the result.
• Heat is lost by the body to the cold conditions of the environment (temperature, water, air) by...
• Radiation (cold condition - temperature of the air)This is when the EXPOSED surface area of your skin is warmer than the surrounding air.
  
• This occurs in all air that is less than 96.8 degrees F and from all skin that is exposed.
• So, wear clothes, but remember YOU will lose twice the amount of heat from your head as from the rest of your body, that is why head gear is SO important. Thus the old adage, "if your hands or feet are cold, put on a hat". 
  
• Conduction (cold conditions - temperature and water)
• Heat is conducted from direct contact between your warm body and colder objects. The more dense the object the greater the ability to conduct heat. Heat is conducted from your exposed skin or through clothes; to the ground, to the air, to the kayak seat, from your feet to shoes to kayak hull, from your hands to gloves to paddles shaft, etc.
• So, you must stay dry. Have the proper rain gear, storm gear, and spare dry clothes (that you do not allow to get wet).
• Convection (cold condition - primarily wind)
• Heat will be lost to moving mediums, the denser and faster the moving mediums the faster the heat loss. You will lose heat more quickly in fast current than in still water. You will lose heat faster the faster the air is moving, this is 'wind chill'. This is the importance of wearing something to 'break the wind', such as a paddle jacket, dry top, etc.
• Evaporation - This heat loss is due to your body's processes of converting water from liquid to gas. Perspiration is the evaporative process your body uses to cool itself during exercise. Insensible Perspiration is the evaporative process your body uses to maintain 70% humidity  next to skin, which can be a lot of water particularly in a cold, dry environment. Respiration is the evaporative process that occurs when air is heated as it enters the lungs and is exhaled with moisture content from your body.
• Evaporation processes are natural functions. There is nothing you can do to retain heat in regard to evaporation. But you can breath through a light covering over the nose and mouth to pre-warm the air that you are breathing.  

Sidebar: Knowing about the constant loss of water due to evaporation, it is important to stay hydrated.

• Preventing hypothermia:
• Retaining your heat and producing heat are how you prevent hypothermia.
• More on heat retention:

• There are FOUR ways to increase your body's ability to retain heat while kayaking.
• 1) Practice being in the cold. That's right, acclimate and become used to physical exertion in the cold. The body does a wonderful job of adapting to different conditions. If you spend all day and every day in the warm office, you are not going to be physically prepared for a vacation of long cold, wet days of kayaking.
• By spending a few hours outside in the cold a few times a week, you can prepare yourself. This does not take a big science project. For instance, you'll notice when your hands, without gloves for say 20 minutes, are not as cold after several weeks of 'practice' as they were when you first started.Adventure race team sidebar: Let's say, it is June, you are from southern California and you are going to Poland for an expedition race in the Fall. Consider training at higher elevations at night during the summer, not for the altitude (which won't hurt anyway) but for the cold. Also, consider arriving in Poland a week ahead of the race start and hanging out in shorts and short sleeves a little bit.
• 2) Put on more body fat. Body fat is insulation. Insulation will prevent conductive heat loss. Fat, by the way, is not necessarily bad for you. In fact, your body needs certain fats for health. So, be wise about your nutrition, your diet, and your training.
• 3) Make your rescues proficient. Plan on being in the water! This means consider how long you might be in the water should you capsize. And do not assume that you are not going to capsize. That kind of decision is what causes hypothermia. (see my article on the wet entry)
• And if you have a good kayak roll, do not assume that you will be able to roll in cold water. The effects of fatigue, exhaustion, and the shock of cold water immersion will likely cause you to miss.(cold shock from immersion coming in another chapter)
• And if you are not real proficient at wet exits and re-entries practice some more. Again, the shock of cold water immersion and fatigue probably will cause a longer time than usual to sort out the rescue (getting back in the kayak). The less time in the water the less time for the rapid heat loss of cold water conduction.
• 4) Wear the right clothes for the water, which means dress for the water temperature and not the air temperature. Any water colder than 96.8 degrees F can cause hypothermia!  
• Again, plan on being in the water and do not assume you won't capsize.
• And consider, given the possible conditions, how wet are you going to get while kayaking. Kayaking with a light wind is going to be a lot dryer than kayaking into 20 mph winds and the resulting waves.
• But do not assume that the weather is not going to change. This is another decision which causes hypothermia.
• The only way to know what clothes to wear for the water temperature is through practice. Everyone is different with different abilities to ward off the causes of hypothermia.  
  

• And there are two ways to retain heat while beached up.
• 1) Get in your dry non-paddling clothes (that you have brought in a dry bag). These clothes you never get wet and never paddle in.
• 2) Get inside your sleeping bag and use an insulating pad between your sleeping bag and the ground.
  

• Heat production:
• There are THREE ways to produce heat to prevent hypothermia.
• 1) The body produces heat by the digestion and utilization of food. This is the main fuel source for the body's furnace. While in cold conditions you have got to eat to stay warm. And to digest the food you have got to stay hydrated. You can not digest food without water.
• A little about food. Carbohydrates, with 5 calories/gram are quickly released into blood stream for sudden brief heat surge. Carbs are the best to use for quick energy intake especially for mild cases of hypothermia. Proteins, with 5 calories/gram are slowly digested and release heat over a longer period of time. Fats, with 9 calories/gram are slowly released but are good because they release heat over a long period, but it takes more energy and water to digest fats.
• 2) Heat is also produced during exercise, in our case paddling. But, you need to remain fueled to continue paddling  Shivering is a natural mechanism that creates involuntary exercise and produces heat. But, if you are shivering, you are losing to hypothermia. You need to retain or produce more heat.
• 3) The body can also gain heat from external sources. These can include but are not limited to warm food and drink, chemical heat pads, fire, and of course the sun.
• While paddling you can drink warm liquids that you have already prepared from a thermos. You can eat warm food that you have already prepared from aluminum foil or in the case of freeze dried foods, from the container they come in. Before you paddle, prepare a freeze dried meal with boiling water in its container, leave a spoon in it, and it's ready to eat and warm when you need it.
• And while paddling you can utilize chemical heat pads by placing them inside your paddling jacket or pants (however, don't place them directly against the skin).
• If you have beached up you can build an emergency fire, prepare warm food and drink, and use heat pads.