Get Cold, Get Hot, Get Fit
You probably already know that shivering in the cold is good exercise. It uses a lot of energy to generate enough heat to keep your core body temperature at an acceptable level.
Even better, though, is getting cold without shivering. Decades ago NASA scientists, and their equivalents in the former Soviet Union, discovered how the generation of body heat from exposure to cold provides health benefits akin to exercise. It gave astronauts and cosmonauts a leg up on staying fit in space. On top of that, adaptation to cold temperatures not only enhanced their fitness, it simultaneously diminished their appetites.
Research on this topic now comes under the umbrella terms ‘cold thermogenesis’ or ‘non-shivering thermogenesis’ – i.e., the generation of body heat by getting cold. The amount of heat released can be phenomenal. For example, when you get cold-adapted, exposure to sufficient cold for about 3 hours (to skin temp of 50-55 F) can burn around 3800 calories. Compare that with running a marathon (26.2 miles) that burns about 2600 calories.
Adding all this up, you can get cold, get hot (burn more calories), get fit AND eat less. What an unbeatable combination of outcomes!
How is this possible? This is where we look to see what happens in two kinds of fat cells: White fat (white adipose tissue, WAT) and Brown fat (brown adipose tissue, BAT).
WHITE FAT VS. BROWN FAT
WAT is the most familiar type of fat. That is what accumulates in and around the abdomen, thighs, hips, arms, and elsewhere. Its main function is storage. It is the fat of obesity.
BAT, on the other hand, consists of a small amount of dark-celled tissue around the neck and shoulders. It can also be found in the chest and down the spine. BAT is brown because of a high density of mitochondria, the little furnaces in cells that generate energy.
The neat thing about BAT is that it can be activated to harvest storage fat from WAT and turn it into heat. The main activator for BAT is … drumroll please … exposure to cold. Yup, BAT burns WAT!
Newborn babies have the most BAT. They are basically little butterballs of BAT. As adults, women generally have more BAT than men. Furthermore, leaner people have more BAT than the obese.
The good news for the obese is that, even though they may have little or no detectable BAT, they can build it back up by slimming down. The more they slim down, the more BAT builds up, the more effective cold thermogenesis becomes for the metabolism of even more fat.
KEY FEATURE OF BAT FOR FITNESS
One of the most amazing features of BAT is that developmentally it is related to muscle tissue. This means that BAT and muscle tissue share certain aspects of metabolism, one of which is activation by exposure to cold. This explains the observation that activating both BAT and muscle goes hand in hand in the cold.
It also explains why the effects of cold exposure during exercise can boost fitness beyond a room temperature workout by itself. Athletes in winter sports have known about the performance enhancing benefits of cold exposure for decades. More recently, combining exercise and cold exposure have become the ‘secrets’ of such world-class athletes as Michael Phelps and Lance Armstrong. Athletes in professional sports of all kinds are now sitting up and taking notice of what this combination can do for their fitness and performance.
GETTING SUPERFIT IN THE COLD
Wouldn’t you know it, at least one company has developed a fitness program around cold exposure. The company, Vasper Systems LLC, offers a program for high-level athletes and other super-serious fitness folks. It combines cold exposure with working out. You can truly get superfit with it, although it might be a bit pricey for most of us.
Fortunately, you can achieve everything the pros do right in your own home, at a fraction of the cost. You can swim in a cold pool or in the ocean if it is cold enough. Barring that, you can wear a vest with big pockets full of ice packs while you spin on a stationary bike.
If your winter provides cold enough weather, you can work out outdoors in minimal clothing.
However you do it, cold exposure is a boost to fitness all by itself. Exercising in the cold is like putting your fitness program on a rocket.
HOW TO GET COLD
The key to getting cold is doing it safely. This make take some adapting to increasingly lower temperatures over a few weeks until you can handle it without getting frostbite or other skin damage.
How low can you go? A slow adaptation over time can help you develop tolerance to ice baths lower than 50 F. In fact, the target temperature for best results is to get your skin temperature to 50-55 F, as measured by an infrared skin thermometer. Many folks have found that ice baths down to 45 F are not only tolerable, they are invigorating and enjoyable.
If you really want to see what is possible, run a Google search on Wim Hof (aka, the ‘Iceman’) to see how long a man can sit in pure ice.
Of course, you don’t have to be extreme, you just have to get cold.