The full New York Times article can be read here.
The piece focuses on the question of whether it is ever too cold to exercise. John W. Castellani, an exercise physiologist at the Army Research Institute of Environmental Medicine and lead author of a 2006 position paper from the American College of Sports Medicine on exercising in the cold, provides much of the information in the article. In a nutshell, Dr. Castellani says that the answer is “no” it is never too cold to exercise – while it can most certainly be too hot to exercise.
Of particular interest to competitive skiers is the issue of asthma. Asthma is commonly thought to be exacerbated by extreme cold, and that lungs can be damaged, even frostbit, by the cold.
But, no matter how cold the air is, by the time it reaches your lungs, it is body temperature. And athletically induced asthma is not triggered by the cold – it is the dryness of the air that causes the problems.