Air pollution: Exercise with caution

If you live in an area with polluted air, that after-dinner walk could do more harm than good, says the American Lung Association (ALA). Why? When we exercise, we breathe more deeply, mostly through the mouth. This bypasses the natural filtering function of the nasal passages, making us more vulnerable to the damage air pollutants can cause. Breathing lead, fine particles and gasses such as ozone and carbon monoxide can increase the odds of developing health problems like heart or lung disease, especially for older adults and children.The ALA recommends these tips to deflect the damage: Avoid midday or afternoon outdoor activities, when pollution levels tend to be highest. Steer clear of congested streets. Up to 50 feet from the roadway, pollution can be high. Skip outdoor workouts if health officials issue a high-ozone alert or other health warning.