Understanding Sedentary Time Among Youth in the United States: A Mixed Methods Study

Introduction: Poor health outcomes are related to high levels of sedentary time (ST). Accelerometer data show that adolescents and females spend more ST than children and males. Similarly, Mexican American youth spend less ST than youth from other races/ethnicities. Understanding the periods of day during which ST disparities are occurring is important for reducing disparities. Purpose: 1) To compare ST data by periods of the day across sexes, developmental stage, and races/ethnicities among youth in the US. 2) To examine barriers and facilitators to reduce ST among female between 13- to 18-years old. Methods: 1) Youth (N=2,972 between 6-to-18 years) from the 2003-2004 and 2005–2006 NHANES waves reported demographic variables and wore an accelerometer for seven consecutive days to determine ST. Linear regressions were conducted to examine the relationships between ST by periods of a weekday and weekend day and developmental stage, race/ethnicity and sex controlling for BMI, annual family income, and sex or race/ethnicity. 2) Semi-structured interviews (N=18) using the Social Ecological Model as framework were conducted to identify barriers and facilitators to reduce ST; and were analyzed using an inductive qualitative content approach. Results: 1) Adolescents were more sedentary than children during school, afterschool, weekday evening and all periods of the weekend. Females were more sedentary than males in the following weekday periods: during school, afterschool, and the evening as well as in the following weekend day periods: during the afternoon and evening. Differences in ST by race/ethnicity were observed during the weekday evening and the weekend morning periods. 2) The main barriers to reduce ST among female adolescents are lack of motivation, lack of support from teachers, unsafety neighborhoods, COVID guidelines and restrictions, and wintertime. The main facilitators to reduce ST were strategies for self-monitoring, support from parents and siblings, and accessibility to recreational spaces within the neighborhood. Discussion: Findings support developmental stage, race/ethnicity, and sex disparities in ST by periods of the day. Qualitative data support multilevel efforts when designing interventions to reduce ST. All together can inform future interventions on whom and when these need to take place to help reduce ST disparities.