More high intensity physical activity in the population with new method to process ActiGraph accelerometer data

Introduction: Our research group has developed the processing of raw acceleration data to ActiGraph counts for improved assessment of high intensity physical activity. The aim of the present study was to apply this new processing method to large population data and investigate the effect on physical activity compared to the original ActiGraph method.

Method: Cross-sectional data collected in the Swedish population (SCAPIS Gothenburg and LIV) were used including 1094 individuals 20-65 years old. The sample was categorized into a younger (20-49 yrs) and older (50-65 yrs) group. ActiGraph accelerometer data was collected over seven days and different physical activity measures, their combinations and patterns were generated and investigated using the original and new processing method to generate activity counts.

Results: There was a clear increase in high intensity physical activity with the new processing method, especially in younger individuals and in males. For example, the proportion of young males with high intensity physical activity changed from 27% with the original method to 46% with the new method (p=0.03), and from 27% to 35% in young females (p=0.29). The corresponding changes in older individuals were from 10% to 14% in males (p=0.09) and from 8% to 10% in females (p=0.37).

Conclusion: The new processing of ActiGraph acceleration data captures more high intensity physical activity in the population. The importance of this development depends on the specific population investigated and the distribution of the physical activity intensity level.