Physical activity patterns among walkers and compliance with public health recommendations.

PURPOSE: Walking is the most common leisure-time physical activity (LTPA) among U.S. adults. The purpose of this study was to estimate the prevalence of walking for physical activity and the proportion of walkers who met current public health physical activity recommendations.
METHODS: We analyzed data from the 1998 Behavioral Risk Factor Surveillance System, a collection of state-based, random-digit-dialed telephone surveys of adults. Physical activity measures included the type, frequency, and duration of the two LTPAs in which respondents engaged most often during the previous month. We calculated the prevalence of walking and the prevalence of three physical activity patterns defined by combinations of walking duration and frequency. We also examined the effect on these patterns of participating in a second LTPA.
RESULTS: In 1998, an estimated 38.6% of U.S. adults walked for physical activity. Among walkers, 21.3% walked a minimum of 30 min five or more times per week. This approximates compliance with current physical activity recommendations. Compliance increased to 34.5% when the criteria were relaxed to include at least 150 min of walking per week accumulated over three or more occasions. Relaxing the criteria further to include a minimum of 150 min.wk(-1) regardless of frequency produced only a small increase in compliance (37.6%). However, compliance with each of these three activity patterns approximately doubled when a second LTPA was taken into account.
CONCLUSIONS: Less than 40% of walkers complied through walking with even our most liberal physical activity pattern (> or =150 min.wk(-1) regardless of frequency). For walkers to meet current public health recommendations, many need to walk more frequently and/or to engage in additional physical activities.