One of the myriad ways human beings vary is in their preferences toward their different temperatures. The age-old “nature versus nurture” debate plays a factor, yet the “objectivity versus subjectivity” uncertainty faced new scrutiny this week.

Just as some might enjoy sleeping close to the warmth of a fire or prefer driving with cold air blowing in their face, while others do not, many people also divide when it comes to working out. Warm temperatures can make the body work harder to accommodate extra sweat and fatigue, but is it possible the reverse is true regarding cold temperatures? This is a question that experts have pondered for years.

To help kick off the new year, NPR released an article on Tuesday featuring quotes from such individuals.

Story author Paul Chisholm tested some claims from Dutch athlete Wim Hof, who purports benefits gained by his conscientious choice to train in frigid temperatures, by reviewing them with leaders in the medical field, writing:

Many of the purported benefits of cold hinge on brown fat, sometimes referred to as “good” fat. Long known to exist in human infants, brown fat burns calories and generates heat.

Dr. C. Ronald Kahn, a researcher at the Joslin Diabetes Center at Harvard Medical School, was among the first scientists to document the existence of brown fat in very small amounts in adults in the mid-2000s. 

People can increase their levels of brown fat by being in mildly cold environments, Kahn says, though the effect on the number of calories they burn will be relatively small.

 “The average person will burn an extra 100 to 200 calories a day when brown fat is activated,” Kahn says. “But if you go eat half a muffin, forget it.” 

A second way that people can burn extra calories when they’re cold is through shivering. But Kahn doesn’t suggest that strategy, either, because shivering makes most of us miserable.

“It’s a way to burn extra energy,” Kahn says. “But I don’t think there’s any data to say that this is a good way to lose weight … because it’s not comfortable.”

Furthermore, people often warm up when they exercise, notes John Castellani, a research physiologist with the U.S. Army Research Institute of Environmental Medicine. Since you have to feel cold to burn those extra calories, Castellani says, people who exercise outside might not actually be burning any more calories than those who are in a warm room. … 

The bottom line is, there is little evidence so far to suggest that training in cold weather makes you healthier, or that you can burn significantly more calories. The physiologists Shots talked to all agreed on one thing: There simply hasn’t been enough research to say one way or another.

Indeed, extreme temperatures, either hot or cold, often make physical activity harder to maintain because of the added discomfort. Still, overcoming them is ought to be a higher priority for most than determining which offers more exercise benefit. Especially if they are debating the inquiry while living a sedentary lifestyle.

To read Chisholm’s full writeup, click here.