Changes in American adolescents' outdoor time over two decades

Spending time outdoors provides opportunities for physical activity, exposure to natural light, and social contact. Although young people's time use has changed substantially in recent decades, little is known about long-term trends in adolescents' outdoor engagement. This question is especially important because adolescence is a period of major life transitions and the development of lasting behavioral habits. This study examines 20-y trends in time spent outdoors among American adolescents using time-diary data from 14,235 individuals aged 15 to 19 in the 2003-2023 American Time Use Survey, a nationally representative survey of the US population. We describe trends in outdoor exposure and examine associations between outdoor time and leisure behaviors, including computer use for leisure, indoor physical activity, and time spent with friends. We find that outdoor engagement among boys has declined sharply, erasing a long-standing male advantage and causing boys' participation levels to converge with girls' at similarly low rates. Greater time spent in computer-based leisure was associated with less outdoor time, particularly among boys, whereas time spent with friends was positively associated with outdoor engagement for both sexes. Indoor physical activity did not change over the observation period and did not offset declines in outdoor time. These findings suggest that broader changes in leisure activities may be reshaping how young people engage with outdoor environments. Further research is needed to better understand the factors underlying these trends and their potential long-term implications.