Korean Adolescents before and after COVID-19: Changes in Physical Activity, Mental Health, and Hygiene Management

Background: Adolescence is when health behaviors, namely, physical activity (PA), mental health, and hygiene management, are established. As the young represent our future societal welfare, their health requires attention, particularly in the face of a pandemic. We explored changes in Korean adolescent PA, mental health, and hygiene management before and after the COVID-19 pandemic to identify recommendations for improving adolescent health. Methods: We collected 2019-2021 data from the Korea Youth Risk Behavior Surveys from the Korea Disease Control and Prevention Agency for 166,590 middle and high school students (2019: 57,069; 2020: 54,809; 2021: 54,712). We analyzed seven variables (regular PA, high-intensity PA, and strength exercise participation, stress recognition, sleep-time satisfaction, brushing practice, and handwashing practice) to examine changes in adolescent behavior during these years. Results: The findings indicated statistically significant differences in all seven variables over the three years (P<0.05). Specifically, regular PA was higher in 2019 and 2021 than in 2020; high-intensity PAs were highest in 2019, followed by 2021 and 2020; strength exercises were the highest in 2020, followed by 2021 and 2019; stress recognition was higher in 2019 and 2021 than in 2020; sleep-time satisfaction was the highest in 2020, followed by 2021 and 2019; brushing practice was the highest in 2019, followed by 2020 and 2021; and handwashing practice was the highest in 2020, followed by 2021 and 2019. Conclusion: The results recommend the need to encourage structured moderate-to-vigorous adolescent PA and systematic health education to improve Korean adolescent health behavior after COVID-19.