Sunday 18 November 2012

COLD-HN

Winter Training Cycle

Canadian Forces Winter Warfare Advanced (WWA) course
Courtesy of CF Combat Camera
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A reality of being living in the Northern Hemisphere, it is cold and wet half the year. This is a combination of late fall, winter and early spring. That is a long period of time when the environment will complicate our training rotation. Do we stop training because it is cold and uncomfortable? Do gunfights, security threats and missions only happen on bright and sunny days? Is stress management through hard play any less in the colder times of the year? Obviously, the answer is NO, to all three questions. Training in adverse weather prepares us for operating in adverse weather conditions. The challenges presented when training, operating, and playing in cold wet environments is easily mitigated through proper preparation. Remember, the mnemonic: COLD-HN.



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Clean

This extends to both clothing and body. Clean technical clothing will work properly, either wicking or insulating. When conducting extended training or play, clothing will become laden with residue of sweat inside and grime on the outside. This will reduce the breathability of wicking layers and water/wind proof shells. An insulating layer that is dirty will compact and not trap body heat to keep you warm. Prior to the colder months, I prepare my technical clothing with proper technical washes and treatment.

The buildup of dried perspiration, grime and the natural oils of the body will decrease the skin’s thermoregulation capacity. A field hygiene regimen is required; especially on extended operations, training and recreation.

Overheating

When dressing for cold weather training, you should feel a slight chill when inactive. Once you ramp up your activity level, large muscle groups start heating up you will become quite warm. Work and travel at a planned pace to avoid overheating. Avoid overheating by ventilating. Making use of pit zips, leg zips, and removing head gear are ways to ventilate. Overheating will lead to sweating. Once you are wet, you will get cold. Sweat and moisture will, also, reduce the effectiveness of your technical clothing.

Layers

Layering simply means wearing a combination of clothes to help regulate your temperature and keep warm and dry. The layers you wear for an activity are matched to the weather and your physical intensity level.  There are five layers: base, light insulating, heavy insulating, windproof/waterproof layer and extremities. Each layer has a specific role to play in staying warm and dry. The base layer wicks moisture away from your skin to keep you dry and warm. A form fitting, wicking material, like Polypropylene, silk, polyester, Thermax, and Thinsulate, is best. The light insulating layer is for trapping body heat, thus keeping you warm while still wicking moisture from the base layer to the windproof/waterproof layer. It should be worn looser than the base layer, but to operate correctly it needs to maintain contact with the base layer.  Soft shells and micro-fleece are types of light insulating layers. The heavy insulating layer traps body heat keeping you warm but has limited ventilation because of thickness. This layer is used primarily during static portions of extended stays in the cold and arctic. When not worn, it must stored safely from environmental moisture; usually in your day bag or assault pack. It should not be worn during intense physical activity. The windproof/waterproof layer allows moisture to escape while blocking wind, and repel water. Common windproof/waterproof layer are Gore-Tex hard shells and hard shells of comparable waterproof breathable materials. Pit zips, ankle zippers (for pants), and ventilation ports are required in a tactical work or active recreation. Due to the rough nature of our work and play, any outer layers must be robust enough to resist tears and abrasions. With the core protected, extremities need to be appropriately covered. Wear a hat, mittens or gloves, socks and boots that compliment tactical work or active recreation and weather conditions. Wind blocking fabric is crucial for hats and gloves. Fleece is warm but has no protection from wind. Proper layering will not only make you more effective during cold weather endeavors, but will also keep you from becoming a casualty.

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Dry

Stay dry. This means avoid overheating, keep your clothing dry on the outside, and change clothing as it becomes damp with perspiration. Use pit zips, ankle zippers (for pants), and ventilation ports to balance your heat and activity. Remove extremity clothing to ventilate.  Keep your gloves off the ground by using integral loops and clipping them to your rig with a gear clip. Hats go in pockets when ventilating. Never sit in the snow or wet; cut some evergreen boughs to act as a barrier between you and the ground. Carry extra socks in your day bag so the opportunity presents itself; put on dry socks. Stay dry.

Hydration

Dehydration is quite common in cold weather. Cellular respiration requires water. You must be properly hydrated for the body to function properly including the ability to thermo regulate. Pre-hydrate days before any planned activity. People do not want to drink cold water because it lowers their core temperature and temporarily chills them. Carry a thermos and refill it when you stop for ‘brew ups’. Avoid caffeinated drinks as they are diuretic. Additionally, on extended cold weather activities include re-hydration as part of the evening or base camp routine.

Nutrition

You have to put good fuel in the engine for it to run. Along with water, the body needs calories to fuel activity and to burn to stay warm. During cold weather activities, it is not the time to count calories and worry about your fad diet. The body needs fat, carbohydrates and protein in that order. Fat gives quick energy and creates heat as it is digested. Carbohydrates, the more complex the better, are time release fuel for the body. Protein is slow for the body to convert into energy but is required for maintenance. Regular meals with frequent snacks are required when training or playing in cold weather. 

Whether you are snowshoe geo-caching, exercising your tactical element or responding to an emergency, cold wet environments are part of life here. Proper planning and preparation will allow you to be more effective, sustain longer periods and enjoy cold weather activities. Remember, the mnemonic: COLD-HN. Get out there and get training.

Take care out there

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