Date of Award


Document Type

Campus Access Thesis


Epidemiology and Biostatistics



First Advisor

Matteo Bottai


This paper looks at sex- and age-specific percentiles curves for several measures of physical activity by gender and age group. Accelerometer data from healthy participants in the National Health and Nutrition Examination Survey study, a program of studies designed to assess the health and nutritional status of adults and children in the United States has been utilized here. Two popular measures of physical activity, time spent in moderate-to-vigorous physical activity and sedentary time, along with new measures that summarize daily cumulative physical activity and its spread over minutes in a day and over days in a week are considered. We derive percentiles charts that are analogous to growth charts and that can be used, for example, to assess individual activity levels, to evaluate intervention programs, or to track individual changes over time.