Peer Similarity in Physical Activity and Weight Status During Physical Education Class

Purpose: Examined how moderate-to-vigorous physical activity (MVPA) and weight status during physical education (PE) class was related to peer MVPA and weight status. Design: Data collected during the first and last weeks of a semester-long PE class. Setting: Houston, Texas charter school. Participants: Adolescents (n = 156; 13.51 ± 1.45 years old; 52.6% female; 85.4% Hispanic, 14.1% African American, 0.5% Asian) nominated up to 3 female and 3 male students they felt closest to in PE. Measures: MVPA during PE was assessed by heart rate throughout the semester. Body mass index (BMI) z-score was calculated from height and weight measured at the beginning and end of the semester. Analysis: Exponential random graph models explored friendship existence, formation, and maintenance in these networks. Separable temporal exponential random graph models examined how MVPA impacted friendships forming or maintaining over the semester. Results: Students with higher MVPA were more likely to receive a new nomination from a student throughout the semester (E = 0.007, P < .03), but not to send a new nomination themselves. Students with higher BMI z-scores were significantly less likely to send a nomination at baseline (E = −0.11, P = .04); however, this effect was not significant at semester’s end. Conclusions: MVPA opportunities during PE may be a mechanism for youth to establish friendships, making PE important for adolescent social and physical health. Larger scale research is warranted.