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Physical Activity: Transportation and Travel Policies and Practices


What the Task Force Found

About The Systematic Review

The Task Force finding is based on evidence from a systematic review of 1 study (search period 1990 - 1998). The review was conducted on behalf of the Task Force by a team of specialists in systematic review methods, and in research, practice, and policy related to increasing physical activity.


There is no information for this section.

Summary of Results

  • Six months following implementation of an intervention that made free transit available to university students, 57% more students chose walking over driving, with a sustained effect of 14% after 1 year.

Summary of Economic Evidence

An economic review of this intervention was not conducted because the Task Force did not have enough information to determine if the intervention works.


Applicability of this intervention across different settings and populations was not assessed because the Task Force did not have enough information to determine if the intervention works.


Evidence Gaps

Each Community Preventive Services Task Force (Task Force) review identifies critical evidence gaps—areas where information is lacking. Evidence gaps can exist whether or not a recommendation is made. In cases when the Task Force finds insufficient evidence to determine whether an intervention strategy works, evidence gaps encourage researchers and program evaluators to conduct more effectiveness studies. When the Task Force recommends an intervention, evidence gaps highlight missing information that would help users determine if the intervention could meet their particular needs. For example, evidence may be needed to determine where the intervention will work, with which populations, how much it will cost to implement, whether it will provide adequate return on investment, or how users should structure or deliver the intervention to ensure effectiveness. Finally, evidence may be missing for outcomes different from those on which the Task Force recommendation is based.

Identified Evidence Gaps

Environmental and Policy Approaches

  • What characteristics of a community are necessary for the optimal implementation of policy and environmental interventions?
  • Does the effectiveness vary by type of access (e.g., worksite facility or community facility) or socioeconomic group?
  • How can the necessary political and societal support for this type of intervention be created or increased?
  • Does creating or improving access motivate sedentary people to become more active, give those who are already active an increased opportunity to be active, or both?
  • If you build it, will they come? In other words, is enhanced access to places for activity sufficient to create higher physical activity levels, or are other intervention activities also necessary?
  • What are the effects of creating new places for physical activity versus enhancing existing facilities?
  • Which neighborhood features (e.g., sidewalks, parks, traffic flow, proximity to shopping) are the most crucial in influencing activity patterns?
  • How does proximity of places such as trails or parks to residence affect ease and frequency

General Research Issues


Several crosscutting research issues about the effectiveness of all of the reviewed interventions remain.

  • What behavioral changes that do not involve physical activity can be shown to be associated with changes in physical activity?
    • For example, does a decrease in time spent watching television mean an increase in physical activity or will another sedentary activity be substituted?
    • Does an increase in the use of public transportation mean an increase in physical activity or will users drive to the transit stop?
  • Physical activity is difficult to measure consistently across studies and populations. Although several good measures have been developed, several issues remain to be addressed.
    • Reliable and valid measures are needed for the spectrum of physical activity. Rationale: Current measures are better for vigorous activity than for moderate or light activity.
    • Sedentary people are more likely to begin activity at a light level; this activity is often not captured by current measurement techniques.
    • Increased consensus about “best measures” for physical activity would help to increase comparability between studies and would facilitate assessment of effectiveness.
  • Note: This is not intended to preclude researchers’ latitude in choosing what aspects of physical activity to measure and to decide which measures are most appropriate for a particular study population. Perhaps a useful middle ground position would be the establishment of selected core measures that most researchers should use which could then be supplemented by additional measures. The duration of an intervention’s effect was often difficult to determine.


Each recommended and strongly recommended intervention should be applicable in most relevant target populations and settings, assuming that appropriate attention is paid to tailoring. However, possible differences in the effectiveness of each intervention for specific subgroups of the population often could not be determined. Several questions about the applicability of these interventions in settings and populations other than those studied remain.

  • Are there significant differences in the effectiveness of these interventions, based on the level or scale of an intervention?
  • What are the effects of each intervention in various sociodemographic subgroups, such as age, gender, race, or ethnicity?

Other Positive or Negative Effects

The studies included in this review did not report on other positive and negative effects of these interventions. Research on the following questions would be useful:

  • Do informational approaches to increasing physical activity help to increase health knowledge? Is it necessary to increase knowledge or improve attitudes toward physical activity to increase physical activity levels?
  • Do these approaches to increasing physical activity increase awareness of opportunities for and benefits of physical activity?
  • What are the most effective ways to maintain physical activity levels after the initial behavior change has occurred?
  • Are there other benefits from an intervention that might enhance its acceptability? For example, does increasing social support for physical activity carry over into an overall greater sense of community?
  • Are there any key harms?
  • Is anything known about whether or how approaches to physical activity could reduce potential harms (e.g., injuries or other problems associated with doing too much too fast)?

Economic Evidence

The available economic data were limited. Therefore, considerable research is warranted on the following questions:

  • What is the cost-effectiveness of each of these interventions?
  • How can effectiveness in terms of health outcomes or quality-adjusted health outcomes be better measured, estimated, or modeled?
  • How can the cost benefit of these programs be estimated?
  • How do specific characteristics of each of these approaches contribute to economic efficiency?
  • What combinations of components in multicomponent interventions are most cost-effective?


Research questions generated in this review include the following:

  • What are the physical or structural (environmental) barriers to implementing these interventions?
  • What resource (time and money) constraints prevent or hinder the implementation of these interventions?


Study Characteristics

  • The one included study used a time series design to measure the proportion of university students who walked to school instead of driving once free transit was made available.


Heath GW, Brownson RC, Kruger J, Miles R, Powell KE, Ramsey LT, Task Force on Community Services. The effectiveness of urban design and land use and transport policies and practices to increase physical activity: a systematic review. Journal of Physical Activity and Health. 2006;3(Suppl 1):S55-76.