Variability of Physical Activity During Physical Education Lessons Across Elementary School Grades

Abstract

The magnitude and source (e.g., school, week) of variability in physical activity during 324 indoor elementary school physical education (PE) lessons (3rd through 5th grade) taught by PE specialists in 20 schools in Minnesota and Texas was examined. Student activity variables included (a) vigorous physical activity (VPA) minutes and proportion of lesson, (b) moderate-to-vigorous physical activity (MVPA) minutes and proportion of lesson, and (c) lesson energy expenditure (EE) and lesson expenditure rate. Although lesson length remained constant, PE provided increased activity as children moved from 3rd through 5th grade. Regression models, including schools, schools by semester, and weeks explained from 32.5% to 100% of the variability in activity with a much greater proportion of the variability explained in 5th grade as compared with 3rd grade. The magnitude of variation was greater for VPA than MVPA and EE measures, suggesting general measures of activity are more stable than specific measures.