Will the thick layers of smog in Beijing affect the performance of athletes at the Olympics? Experts weigh in.

Thousands of the world's most elites athletes have been journeying from their home countries to Beijing, a city often shrouded in smog, for the Olympic Games.

Over the past few weeks, thousands of the world's most elites athletes have journeyed from their home countries to Beijing, a city often shrouded in a thick cloud of smog, for the Olympic Games.

The Olympians, who have spent years honing their skills to peak at the 2022 Winter Olympics, are now entering a region where the atmosphere could hinder them from achieving their best performance, experts told ABC News.

While people with underlying health conditions such as asthma or chronic obstructive pulmonary disease, and at risk for heart attack are often the most affected by poor air quality, young people, healthy people and athletes can suffer adverse health consequences as well, Dr. Meredith McCormack, associate professor of medicine at Johns Hopkins University and spokeswoman for the American Lung Association, told ABC News.

Any additional particulate, such as the hazardous pollutant PM2.5 or even high counts of tree pollen, can cause inflammation in the airways and diminish the athlete's ability to breath efficiently, Dr. Matthew Heinz, an internist and hospital physician in Tucson, Arizona, and Pima County supervisor for District 2, told ABC News.