For people who like to work out and run outside, autumn's chilly temperatures are usually a welcome respite. After all that summer humidity, crisp fall air is all the boost you need to dig down and get some more gains.

But when winter starts creeping in, the air gets frosty and can feel like it’s burning your lungs when you inhale. The question is: Why?

First of all, understand that it doesn't necessarily come from a lack of fitness—more like a lack of humidity.

“Normally, the nose and mouth generally can warm and humidify the air we breath into our lungs,” says Albert A. Rizzo, M.D., F.A.C.P., F.C.C.P., senior medical advisor at the American Lung Association and section chief of pulmonary medicine in the Christiana Care Health System in Newark, DE. “But exercise requires more oxygen, and we need to breathe more rapidly and with larger breaths. That rate that can overwhelm our normal humidification process. This is accentuated in cold temperatures, leading to drying of the airways, which can feel like a burning sensation.”

That "burning throat" symptom can occur in both untrained people and elite athletes, depending upon your exercise environment. Poor air quality—high in ozone, pollen, or pollution—can be problematic and can cause respiratory symptoms in anybody, so be aware of the air quality when exercising outdoors. Typically, though, people don’t feel a burning in their lungs unless they're exerting themselves more in cold, dry air, says Bruce D. Johnson, Ph.D., professor of medicine and physiology, and director of the Human Integrative and Environmental Physiology Laboratory at the Mayo Clinic. “I have climbed mountains, skied marathons, hiked in Antarctica, run marathons, swam, rowed competitively, etc., and the only time I have felt this is in colder events with heavier exertion and dryer air.”

That said, your baseline fitness can play a role. “If you are not a regular exerciser or have been away from exercising for awhile, the increased movement of air, especially in cold air, that you move through the airways can make this sensation be a bit more prominent, says Rizzo. "The more fit you are, the less likely it is to occur. But even elite athletes, when pushing their limits, can feel this sensation.”

As far as keeping it from happening, or gaining some relief from the burning, experts recommend wearing anything over your mouth and nose that warms, humidifies, and conditions the incoming air, like a Buff, facemask, or even a bandana. It'll help by slowing down the volume of air coming in that needs to be "conditioned".

“Ideally, exercising indoors—a fitness center or pool—where controlled temperature and humidification exist is the best way to prevent this issue,” says Rizzo. “However, if you must be outdoors, be considerate of the temperature and think twice about the intensity and duration of your exercise outdoors, along with planning to wear a mask or scarf.” Also, try to be more conscious of breathing through your nose since it does a better job of warming the air you'll inhale through the mouth.

Ultimately, the sensation depends upon the person. Because it’s a fairly nonspecific sensation, it’s important to differentiate it from chest burning or other symptoms, says Johnson. “We all perceive things a little differently—it may be happening because of gastrointestinal-related conditions [indigestion, heartburn] as well as the cardiac-related issues.”

Rizzo agrees, and adds that the presence of an underlying respiratory condition, such as asthma, can also make the airways more sensitive to the cooling and drying effect since tightening of the airways can cause a burning sensation and shortness of breath.