ABSTRACT
Transportation policies have been shown to impact population levels of physical activity and obesity.1-5 Governments make many decisions that inuence people’s choice of transportation modes. In most places there is a wide array of transportation options, but simple behavioral economics may cause people to favor certain modes of transportation over others. In places where governments have invested heavily in public transit and in building cities and towns that are conducive to walking and bicycling, obesity rates are lower than in places that are more car dependent.3,6 Active transportation has a host of other benets, including economic savings, energy conservation, reduced vehicle emissions, and decreased requirements for roads and parking lots.7,8
In the United States, the percentage of trips taken by walking and public transit has been declining since the 1960s,9 with only a slight increase occurring during the past decade.10 Bicycling rates have remained low, at around 1-2% of total trips. In contrast, the percentage of trips taken by private vehicles has gradually risen and now stands between 80% and 90% of total trips. Similar trends have been observed in many other industrialized nations including Great Britain11 and Finland.12 The percentages of trips taken by walking and bicycling in developing nations such as China and India are also declining,13 as these countries are becoming more dependent on automobiles.
