Do you start coughing and wheezing with exercise when the weather turns cold? Well, you aren’t alone. Could be a bout of exercise –induced asthma or as the scientific community refers to it, exercise-induced bronchoconstriction, or E.I.B. “It’s a reversible, obstructive airway disease” that typically begins about five minutes after you stop exercising — particularly if your exercise was intense, “ between 85-95% maximal HR.” EIB was originally thought to be triggered by exposure to cold air, which led to bronchial constriction, but most researchers no longer consider this to be the primary cause of EIB.

The problem appears to be not with the coldness of the air but with the “dryness.” Lungs need water-saturated air. If the air entering your bronchial tubes is dry, as it usually is in winter, the cells lining your airway release their own moisture to humidify it. The loss of moisture prompt certain cells within the bronchial tube to release allergic chemicals that initiate an inflammatory process, slowly constricting your throat.

EIB has been diagnosed in nearly half of all elite cross-country skiers and many world-class figure skaters and hockey players.  It is theorized that elite endurance winter athletes, especially those training more than 20 hours a week, actually “injure their airways” by breathing so much and so hard. “They take in up to 200 liters of air per minute,” in comparison to perhaps five or six liters per minute at rest, all of which must be humidified.

Well, you may not be an elite athlete, but if you experience symptoms of EIB – make sure you warm up adequately with 10-15 mins. of progressive exercise, breath through your nose (the mucus is moister there then that in your mouth) wear a facemask, and you may want to request a lung-function test. Asthma and EIB can be treated with medication to make your exercise sessions more comfortable.

http://well.blogs.nytimes.com/2010/01/13/why-do-so-many-winter-olympians-have-asthma