Walking Interventions Improve Physical Activity Levels in Sedentary Individuals

June 13, 2007 — A variety of motivational approaches can encourage nearly all individuals to walk more and to increase their walking by at least 30 to 60 minutes per week, according to the results of a systematic review published in the June 9 issue of BMJ.
"Walking has been described as near perfect exercise," write David Ogilvie, MRC fellow, from the Medical Research Council Social and Public Health Sciences Unit in Glasgow, Scotland, and colleagues. "Even walking at a moderate pace of 5 km/hour (3 miles/hour) expends sufficient energy to meet the definition of moderate intensity physical activity. Compared with many sports and other recreational pursuits, walking is a popular, familiar, convenient, and free form of exercise that can be incorporated into everyday life and sustained into old age."
The investigators conducted a systematic review of the best available evidence to determine what characterizes interventions that are effective in promoting walking, who walks more and by how much because of effective interventions, and the effects of such interventions on overall physical activity and health. They searched 25 electronic databases, as well as Web sites, reference lists, and existing systematic reviews, and they also contacted appropriate experts.
Literature search identified 19 randomized controlled trials and 29 nonrandomized controlled studies. Interventions have been tailored to individual needs, ranging from the most sedentary to those most motivated to change. Interventions may target the individual (brief advice, supported use of pedometers, or telecommunications), household (individualized marketing), or groups.
Although these interventions can encourage people to walk more, the sustainability, generalizability, and clinical benefits of many of these approaches are still uncertain. When applied to workplaces, schools, communities, or areas, evidence for the effectiveness of interventions typically depends on isolated studies or subgroup analysis.
"The most successful interventions could increase walking among targeted participants by up to 30-60 minutes a week on average, at least in the short term," the authors write. "From a perspective of improving population health, much of the research currently provides evidence of efficacy rather than effectiveness. Nevertheless, interventions to promote walking could contribute substantially towards increasing the activity levels of the most sedentary."
None of the studies reviewed showed that any short-term benefits associated with pedometers were sustained. Few studies in this review showed clear improvements in health, risk factors for disease, or even in overall levels of physical activity that could be attributed to an increase in walking.
"The need for more intervention research does not obviate the need for those working both in and outside the health services to do something to tackle the public health problems associated with sedentary contemporary lifestyles," the authors conclude. "Therefore, while we still have much to learn about exactly who will benefit from what type of intervention and by how much, this uncertainty should not be used as an excuse for inaction."
NHS Health Scotland, the Scottish Executive Health Department, and a Medical Research Council fellowship supported this study. One of the authors has disclosed selling pedometers in his capacity as a health promotion consultant. Another author has disclosed authoring 3 of the primary studies included in the systematic review but did not evaluate these studies for this review.
BMJ. 2007;334:1204-1213.