Have you ever considered the irony of the treadmill, the stationary bicycle, or the rowing machine? More than 85 percent of Americans drive to work, with an average commute of 26 minutes in each direction. Then some pay for a membership and drive to the gym to re-enact travel on stationary equipment. At first glance, this seems absurd. It’s like opting to watch a rom-com instead of falling in love. But maybe the cardio folks are onto something. Maybe you don’t want to get your exercise during your commute. After all, the gym does have one thing over the highway: The air is much cleaner. Rush hour pumps up the pollution. Sitting in traffic causes automobiles to belch out twice as much nitrogen dioxide, three times as many hydrocarbons, and quadruple the amount of carbon monoxide compared to cruising on the open road. All that braking and accelerating brings out the worst in an internal combustion engine. The result is that you may be sitting in a toxic stew every time you drive to and from work. Exposure to air pollution has been associated with asthma and other respiratory diseases, heart problems, and premature morbidity. It’s sick stuff—and unless you follow the advice of a team of Washington University aerosol scientists, that smog is getting into your car, where you gulp it down with every breath.
This simple trick will help you cut down on exposure to pollutants while you’re in your car.
The October 2017 issue of the journal Atmospheric Environment features the research of Anna Leavey, Nathan Reed, Sameer Patel, and colleagues in a piece charmingly titled “Comparing on-road real-time simultaneous in-cabin and outdoor particulate and gaseous concentrations for a range of ventilation scenarios.” The researchers measured air quality both inside and outside of a car that study participants drove to work. Sometimes they left the windows open. Sometimes they closed the windows and ran the fan. Other times they closed the windows and turned on the air conditioning. After four months of this, they crunched the numbers and came to a straightforward conclusion. “Car drivers can expect their highest exposures [to air pollution] when driving with windows open or the fan on, and their lowest exposures during windows closed or the AC on.” Why, though? Reed, one of the authors of the paper, explained the situation to Science Daily. “The AC is pulling outside air, running through the same filter with the same ventilation path as the fan,” he said. “But there’s one difference: when the AC is operating: You have a cold evaporator that is cooling the air as it passes. …This cold surface attracts the pollutant particles, and they deposit there, as opposed to diffusing it into the air you’re breathing.” Running the air conditioning dropped pollutant levels inside the cab of the car tested by 20 to 34 percent, Science Daily reports. Beyond rolling up the windows and opting to turn on the air, it seems like the next step is eliminating fossil fuels entirely. Imagine a new kind of gym membership: Rather than a keychain fob to swipe at the door, your trainer assigns you a bicycle or hands you a pair of running shoes—and takes your car keys. Imagine if everyone who is physically able to ride a bike or go jogging were to join this gym. Now that would cut down on air pollution.