If you've ever been so cold that your teeth started chattering and your body began to shiver uncontrollably then you've experienced mild hypothermia. Most of us have been there, particularly when we were kids for indeed children are particularly prone to this potentially deadly condition.

Simply put, hypothermia occurs when heat loss from the body outstrips heat production. Even during mild weather hypothermia can occur for outside temperature is just one of a number of factors which contribute to the onset of the condition.

A tired cyclist cruising through the countryside on a fine spring day could be a potential hypothermia victim. If tired, the cyclist's energy reserves are already waning. Being, in all likelihood, sweat-soaked, the cyclist's garments will be sucking heat away from the body at a rate 240 times faster than at the start of the day when presumably the cyclist was dry. Even on a windless day the speed of the cyclist creates its own wind multiplying the rate of heat loss exponentially. Exertion is also contributing to the cyclist's quandary by causing dehydration through sweating and breathing.

Dumb is Dumber

All of these factors working in concert, dehydration and fatigue; outside temperature and dampness could spell disaster. The cyclist's inexperience more than anything else could prove deadly. Ignorance is the number one cause of this number one recreational killer. Armed with knowledge the cyclist can take simple precautions and avoid hypothermia in even its mildest form.

A savvy cyclist will dress in layers, shedding them as body temperature rises, donning them again as it drops. The inside layer will be a thin synthetic such as polypropylene that whisks moisture away from the body. Intermediate, insulative layers will be loose-fitting and made of fleece or wool. A breathable shell made of Gore-Tex will complete the package, acting as a barrier to rain, fog or condensation but at the same time allowing sweat in the form of water vapor to escape. Gloves, possibly in layers, and an insulating helmet liner complete the ensemble of a well-prepared cyclist.

Knowledge will further tell the cyclist that both water and energy will require regular replenishing and by habit the cyclist will frequently consume high-energy foods such as granola bars, trail mix and the like. Such foods contain sugars which provide immediate energy, carbohydrates which release their energy over a moderate period of time and oils and proteins which take the longest to be processed into usable energy by the body. That energy propels the bicycle forward, keeping the cyclist warm at the same time.

The informed cyclist will also recognize that chills and shivering are the earliest signs of hypothermia's onset. The cyclist will know that decision-making will soon become confused and coordination impaired if the condition is allowed to progress. Immediately the cyclist will switch from recreational mode to a survival-bent one, seeking ways to stabilize net heat loss from the body core.

Stumbles, Fumbles, Mumbles and Grumbles

If hypothermia progresses our cyclist must rely on companions to correctly assess the situation. The inexperienced may fail to notice the violent shivering, slurred speech, clumsiness, even irrationality that indicate their buddy is already suffering from moderate hypothermia. If they fail to intervene and the body core temperature of the victim continues to drop then unconsciousness, coma and finally death, all consequences of late-stage hypothermia, can be expected.

Treatment protocols of moderate to advanced hypothermia are complex and ever-changing. In the normal course of things, when adequate preparation and prevention measures are strictly adhered to, no one should ever get beyond the initial symptoms. Accidents do happen, however and a kayak spill in the west coast surf or a slip into an icy creek while hiking could be just the kind of event to precipitate the rapid onslaught of life-threatening hypothermia. The Wet Coast of British Columbia is aptly nicknamed because the conditions which prevail on Canada's west coast are ideal for hypothermia. Anyone, even casual recreationalists, who venture into the wilderness should consider taking a wilderness first-aid course which includes training in hypothermia prevention and treatment. Slipstream Wilderness First Aid offers regular, certified training at many levels of proficiency geared specifically for outdoor recreational settings.

The End

Boots have to fit well. When buying new boots try on several brands, looking for a fit that is comfortable and appropriate for the type of hiking intended. Feel inside for thick seams or irregularities that will rub against your foot. If boots are too loose or too tight they will cause problems as your foot moves or swells during the hike. Boots should be big enough to accommodate an insole and two pairs of socks. A steep uphill grade will cause heel movement in the boot while a downhill grade will cause pressure on the toes. Both actions can cause blisters. The latter can splinter toenails, cut them short before the trip.

Good hiking boots will have a locking cleat by the ankle to allow for tight lacing in one part of the boot and flexibility in the other. For uphills the upper part should be tight. The toe end of bootlaces should be tight to prevent slippage on downgrades. New boots have to be broken in before you start a big trip. Wear them about town for progressively longer periods each day until they feel comfortable for the whole day. Starting a major hike with brand new boots could ruin not only your trip, but that of your companions.

Sock It To 'Em

Socks should be clean and dry. Sand or debris in socks will rub against the foot causing blisters. Wet socks make skin soft and prone to blisters. Hikers should wear a clean pair of socks every day on the trail. That means either bringing enough to last on long trips or washing and drying socks every few days. Inner socks should be ultra-thin and made of polypropolene, a fabric which wicks moisture away from the feet. Outer socks should be moderately thick and be made of wool which insulates even when wet.

At the end of a day's hiking it is a good idea to don a pair of light camp shoes to give feet a rest and boots a chance to dry out. Sandals are nice but may not be the best backup choice if boots become unwearable. Hiking out in sandals or flip-flops could expose your feet to many hazards in especially rough terrain.

Blisters can be prevented by protecting tender spots or pressure points with Dr. Scholl's Moleskin, slippery adhesive tape or adhesive foam padding. Application of tincture of benzoin (Friar's Balsam) to the skin will ensure that adhesive protection will not work loose even under wet conditions. Loose or bunched up coverings can add to problems.

When a hot spot or blister has already formed, Friar's Balsam or adhesive protection should not come into direct contact with the damaged skin. Rather the blister should be allowed to poke through a "doughnut" cut in moleskin to alleviate pressure. Once enough layers are built up, the doughnut hole should be covered with adhesive or a final layer of moleskin for protection.

Prevention The Key

Water blisters, once formed, should not be drained as they will then be open sores susceptible to infection. If blisters break the area must be kept clean and the sterile dressing covering the wound must be changed daily.

Once a blister forms, treatment and protection of the dressing becomes more complicated. Prevention should always be the goal.

The End

Notable Quotes

Great photos in the book and it's very current information.

-- Mark Forsythe; CBC Almanac.