Today’s column is about freezing to death.
Sometimes, right before freezing to death, a person will get naked.
It is also true that a shirtless man, found frozen so rigidly he had to be transported like a desk, whole and immobile, was afterward thawed out and survived. But then again, it’s also true that a person can die of hypothermia at temperatures above freezing, like the Army Ranger candidates who froze to death during a training exercise in a Florida swamp. The cold is a murderous thing, but it also holds within it the power to save, like when trauma surgeons pump dying bodies full of chilled liquids, slowing a patient’s metabolism and buying precious time. Cold can cause squeals of delight in the summer months, soothe damaged muscles after injury, and steal fingertips, toes, tips of noses. It has left a trail of bodies up Everest. It is a fucking menace.
Much like a fancy, tropical lizard, I require close attention paid to my personal warmth. My body is not particularly cold tolerant, and low temperatures make my chest hurt in a squeezing, anxious way. Sturdy northerners are quick to point out that there is no such thing as cold weather, only inappropriate clothing, and while I agree on principle, I do live in the South, which means I’m ill-prepared and also allowed to complain. Listen, I don’t make the rules.
Not everyone shares my aversion. Not only are there those who willingly enter into the cold, there are those who do it for fun. I regret to inform you that there are, in fact, as the Olympics in Pyeongchang have recently confirmed, cold weather sports. And where there are sports, there is Meat Sack. Today’s topic is hypothermia.
Humans are not thermoconforming. We do not allow our body temperature to fluctuate with the weather, instead relying on a suite of physiological traits (like sweating) and behavioral modifications (like going the fuck indoors) to keep a close handle on our precious thermal homeostasis. We are homeotherms, and we regulate our temperature through metabolic activity. And coats. And shivering. Hypothermia, then, is what happens when the body is losing heat faster than it can generate it. Normal body temperature for a human is about 98.6 degrees fahrenheit; a tiny drop down to 95 degrees, and you’re in trouble.
When the body is chilled, things don’t work right. To oversimplify, we humans are electrified bags of goo, the circuitry of which is very sensitive to cold, which explains why early symptoms of hypothermia are lethargy and confusion. The colder the body, the less brain activity there is, and the more confused and sluggish a person can become. This confusion can lead to a lack of awareness of what is happening: being hypothermic impairs your ability to understand that you are hypothermic.
So what does your body do in the cold? First up is vasomotion, which sounds like a terrible DJ name but actually refers to the body’s protective constriction of peripheral blood vessels. It’s a bid to staunch heat loss from the extremities, concentrating warm blood in the center of the body and reducing heat loss from the surface of the skin. Vasomotion is accompanied by shivering—rapid muscle contractions that overtake one’s somatic stillness to help generate extra heat. Athletes exercising in the cold will also get a heat boost from their workout, the furnace of their activity at odds with icy temps. This internal warming in the face of bitter cold is good for maintaining core body temperature and keeping fussy organs toasty, but the vasoconstriction keeping blood from the edges of the body can mean that warm blood from deep within the body doesn’t make it out to fingers and noses, putting our intrepid cold weather athlete at risk of frostbite. (Frostbite occurs when the water in your cells starts to freeze. It is distinct from hypothermia, though obviously they two can occur under similar circumstances.)
In addition to confusion and shivering, mild hypothermia can also make a person feel hungry or nauseous, but the feeling will fade to apathy as the body’s temperature continues to drop. Once you’re around 90 degrees fahrenheit, shivering stops and confusion worsens. This stage is known as moderate hypothermia, but don’t let the name fool you: the next stage, severe hypothermia, means you are probably in a coma and are about to have a heart attack. In the precursor to such an end, the heart, struggling to maintain its electrical regularity in the absence of warmth, will slow down. It may become irregular in its rhythms, flirting with cardiac arrest. It’s at this stage of hypothermia that a person may feel compelled to strip off all their clothing, a phenomenon called paradoxical undressing. Despite all the research done on hypothermia, we’re still not really sure exactly why this happens. Something about the body’s thermoregulators malfunctioning. Suddenly, the victim of hypothermia feels like their skin is much too hot. It’s why bodies are sometimes found frozen and naked in the snow.
Researchers studying lethal hypothermia observed paradoxical undressing in 25 percent of the 69 cases studied. They note that the urge to remove clothing is the result of peripheral vasodilation: the body releases the constriction of blood vessels, resulting in an overwhelming feeling of heat. But they also observed something strange. Bodies were found hidden under beds and behind wardrobes, squished into a shelving half-naked and dead from cold. They named it terminal burrowing behavior, a last-ditch blast from the brain stem producing burrowing behavior the likes of which are associated with hibernating animals.
The smug, heat-seeking side of me would be pleased to report that cold weather activity is inherently dangerous, but alas, so long as one is properly attired, working out in the cold is relatively safe. According a paper written by Dr. Gordon G. Giesbrecht from the Health Leisure and Human Performance Research Institute at the University of Manitoba, “there are few contraindications to full physical activity in environments as cold as even -25 to -30°C. Proper preparation and knowledge will enable safe and productive training and competition.” For some excellent advice on dressing for a jog on Hoth, you can see the paper in full here.
Cold weather athletes will want to watch out for fatigue, as well. The link between fatigue and hypothermia was brought to light when three people died during a 45-mile competitive walk in England, their wet clothes and tiredness resulting in their untimely deaths.
And by the way, the cold pees are definitely a thing. It’s called cold diuresis, and it’s why when a person goes into the cold after being roasty-toasty, they may quickly need to pee. As we learned earlier, the body performs a process called vasoconstriction in response to cold, reducing circulation to the skin and extremities. When this happens, the amount of blood in your core goes up, also boosting arterial blood pressure. Homeostatic nugget that you are, the body tries to lower this pressure by asking the kidneys to reduce your blood volume by taking water out of your blood and sending it to the bladder. It’s also why coming in from the cold can make you thirsty: you made extra pee and now need to rehydrate.
In writing this, I went outside and sat in the cold. I tried to imagine what could be good about the sensation, how the tightness in my chest could be a pleasure. I sucked cold air and turned it into clouds. I had to pee. My brain stem rang loud alarms about imminent danger. I know there are people who enjoy the cold but dear reader, I have not been able to transform myself into one of them. But if you are, stay warm out there. And if you start to ever feel confused or fumbling in cool weather, take it seriously. It might save your life.