Translation of Moderate-to-Vigorous Physical Activity Recommendations into Pedometer-based Stepping Targets in the Lower Mississippi Delta

Abstract

The Lower Mississippi Delta (LMD) region of the United States is characterized by high levels of poverty, physical inactivity, obesity and related chronic diseases. There is a pressing need to identify new strategies that will increase adherence to physical activity guidelines. Walking is an important outlet for physical activity in rural populations; however, the number of steps/day in this population that translate to current physical activity guidelines is not known. PURPOSE: To elucidate how many steps/day equate to standard moderate-to-vigorous physical activity (MVPA) recommendations in a population of the LMD using both accelerometer and pedometer steps. METHODS: The sample included 58 healthy overweight and obese adults who enrolled in a community-based pedometer intervention in the LMD. Each participant wore an Actigraph GT3X accelerometer for one week. A subgroup of 22 participants also wore a Yamax pedometer. Steps/day were measured and self-reported from the pedometer and minutes of MVPA and steps/day were also derived from the accelerometer. Each individual had at least one day of valid accelerometer and pedometer data which resulted in 487 and 87 days of data, respectively. Linear regression was used to assess the relationship between steps/day and MVPA. Stepping targets were calculated based on a mixed model approach to allow for the non-independence of each day of monitoring within individuals. RESULTS: The empirical statistical model indicated time in MVPA is a good predictor of steps/day output from both the accelerometer (r2=0.58; p<.001) and the pedometer (r2=0.53; p<.001). In this population, 30 minutes of daily MVPA equated to 9093 accelerometer steps/day and 8894 pedometer steps/day. 60 minutes of MVPA equated to 13242 accelerometer steps/day and 13100 pedometer steps/day. CONCLUSIONS: These results indicate that the residents of the LMD should be accumulating a minimum of 9000 steps/day to meet the recommendation of 30 minutes/day MVPA. This information is important for setting personal goals for participants when designing community-based interventions in the LMD. Supported by ARS/USDA Cooperative Agreement no. 58-6251-8-038