Researchers know that your body reacts when it’s cold. New fat appears, muscles change, and your level of comfort rises with prolonged exposure to cold. But what all this means for modern human health—and whether we can harness the effects of cold to improve it—are still open questions. One vein of research is trying to understand how cold-induced changes in fat or muscle can help stave off metabolic disease, such as diabetes. Another suggests it’s easier than you might think to get comfortable in the cold—without blasting the heat.
To Haman, these are useful scientific questions because freezing is one of our bodies’ oldest existential threats. "Cold, to me, is [one of] the most fascinating stimuli because cold is probably the biggest challenge that humans can have,” he says. “Even though heat is challenging, as long as I have access to water, and to shade, I will survive fairly well. The cold is completely the opposite.”
“If you're not able to work together,” he continues, “if you don't have the right equipment, if you don't have the right knowledge–you're not going to survive. It's as simple as that." Figuring out how our bodies change in response to such a formidable and ancient opponent offers clues to how they work, and how they might work better.
Haman begins every day with a cold bath or shower. It’s a rush because the cold triggers the body to release hormones called catecholamines, which are involved in the fight or flight response. “I do have that sense of Oh my God, I'm feeling so strong, and I'm awake,” he says. “This is kind of my coffee.”