The Dangers of Outside Workouts
Let's be very clear: I love an outside workout as much as I love a good gym training session. I look forward to my weekly runs on the beach, mountain, and trails more than I enjoy being cooped up in a gym. However, this is something that needs to be said: outdoor workouts, if done in the wrong place, can be hazardous to your health.
According to a study presented at EuroEcho-Imaging 2016, pollution in the air can impair the function of the blood vessels that pull air from the lungs into the bloodstream. This indicates that outdoor exercise in urban areas has the potential to damage the lungs. Worse, it may even lead to decompensated heart failure.
The study involved 10 healthy male volunteers who were exposed to pollutants in an enclosed chamber. During a randomized, crossover study, the researchers piped either ambient air or dilute diesel exhaust (with a PM2.5 concentration of 300 μg/m3) into a chamber for 2 hours. The volunteers were then given an echocardiography test to determine the effects of the pollution on pulmonary vascular resistance.
The tests discovered that exposure to pollution reduced pulmonary acceleration time while increasing pulmonary acceleration slope. The pollution also worsened the function of the right ventricle and decreased pulmonary circulation. Patients with obstructive sleep apnea noticed the most severe pulmonary impact.
As the study proves, air pollution can negatively impact pulmonary function, making it harder for blood to reach the lungs. The longer you're exposed to air pollution, the greater the impairment of the right ventricle—affecting the blood pressure.
An interesting note: the pollution didn't impair pulmonary function when the patients were at rest, but only when dobutamine was administered. Dobutamine stimulates the nervous system similar to the way exercise does. Basically, this indicates that pollution may be more harmful when you are doing exercise, even if it doesn't affect you as much when at rest or walking down the street.
The purpose of this study was to determine how air pollution affects pulmonary function, and the results speak for themselves. The researchers recommend minimizing physical activity when there is heavy air pollution present.
As this indicates, outdoor exercise may put your health at risk. If you're too close to roads or highways, the vehicle exhaust could do serious harm to your lungs. Training out in the countryside, on the beach, or on a mountain trail may not be harmful, but running beside a road may impair pulmonary function.