Which commute is the healthiest?

Vehicles wait during a traffic jam along a major thoroughfare in Beijing August 10, 2007. The Chinese capital will hold a test drill for keeping cars off the road during its 2008 Olympic Games, a crucial hurdle for the city beset by pollution and traffic jams, officials announced on Friday. Between Aug. 17 and 20, about 1.3 million of the city's 3 million vehicles will be ordered off the streets each day depending on whether licence plates end in an odd or even number. REUTERS/Claro Cortes IV (CHINA)

The longer you commute, the worse your health, according to the latest in a string of studies showing that sitting—even in a car—is bad for you. The study, published in the June issue of the American Journal of Preventive Medicine, found that those who have the longest drives to work have decreased cardio fitness, are heavier and have higher blood pressure than those with shorter commutes.

That’s bad news, since the average time driving to work increased from 17.6 minutes in 1983 to 22.5 minutes in 2001.

The question: Is it being sedentary for so long that raises the risk or is it the stress of driving, or both? And is another type of commute, like taking a train or bus any better for you?

In this study, researchers studied about 4,000 residents who lived in metropolitan areas of Texas.  Researchers recorded commuting distances as well as several measures of health including cardiorespiratory fitness, body mass index (BMI), waist circumference, glucose levels, cholesterol and blood pressure. Participants also recorded the amount of physical activity they did.

The study found that people who drove longer distances to work reported doing less physical activity, had decreased cardio fitness and greater BMI, waist circumference and blood pressure. Cholesterol and glucose levels were not affected.

Those who drove only 10 miles or more to work were more likely to have high blood pressure, and those who commuted 15 miles or more were less likely to meet recommendations for physical activity and were more likely to be obese.  Even when physical activity was adjusted for (meaning taken out of the equation), the other risk factors remained, suggesting that long commuters expend less daily energy than others.

The reason blood pressure also increased with driving distance may be linked to the stress of commuting.  Past studies have associated daily commuting with high blood pressure, tension and fatigue.

"Those with longer commutes may be more likely to be exposed to heavy traffic resulting in higher stress levels and more time sitting," says lead investigator of the new study, Christine M. Hoehner of Washington University in St. Louis, Mo.

Commuting by Train

But is commuting by train or bus any better? One study looked at the health of people who took a train from New Jersey to Manhattan. It turns out that if you use public transportation, you spend more time walking – to the train station and to your office – than if you drive. The study found that train commuters walked an average of 30 percent more steps per workday than those who drove to work.  It also found that people commuting by car reported significantly more stress and a more negative mood than those who rode the train.

The Best Commute

Of course, the best way to get to work is to walk or ride a bike—an active commute. One study found that active commuting that incorporates walking or cycling was associated with an 11 percent reduction in cardiovascular risk. Another study found that men with any active commuting (versus none) were less likely to be obese, and had lower risk factors for heart disease across the board.

Since there’s growing evidence that sitting at your desk all day is bad for your health, try to maximize the activity of your commute to your office. If walking or biking isn’t possible, second best is public transportation since. If you must drive to work, as most Americans do, then think about incorporating walking into your day as much as possible to counter all that time you’re sitting.