AUTHOR=Chen Sitong , Yan Jin , Zhao Yaping TITLE=A Trend Analysis of Adherence to the Muscle Strengthening Exercise Guidelines in US Adolescents JOURNAL=International Journal of Public Health VOLUME=Volume 67 - 2022 YEAR=2022 URL=https://www.ssph-journal.org/journals/international-journal-of-public-health/articles/10.3389/ijph.2022.1605022 DOI=10.3389/ijph.2022.1605022 ISSN=1661-8564 ABSTRACT=Introduction: This study aimed to describe the trends of adhering to the MSE guidelines in adolescents using nationally (United States) representative data. Methods: Using the Youth Risk Behavioural Survey data (in 2011, 2013, 2015, 2017 and 2019), this study assessed the trends of adhering to the MSE guidelines in adolescents in the 9th-12th grades. MSE was assessed by one single question from a standardised measurement protocol. The prevalence of adhering to the MSE guidelines (3 or days a week) was calculated, and its trends were estimated. Results: The data were available for 73074 (female = 36497, male = 36108; mean age = 16.04 years, standard deviation = 1.25) participants. A linear declining trend of adhering to the MSE guidelines in participants was found (55.6% in 2011 → 49.5% in 2019, p < 0.005), and this declining trend varied by sociodemographic factors, such as sex. Conclusion: The declining trend of adhering to muscle strengthening exercise guidelines in US adolescents has been a public health priority that should be addressed. Female and older adolescents are key intervention target populations.