Objectively measured physical activity and academic performance in school-aged youth: The UP&DOWN longitudinal study Muntaner Mas, Adrià Esteban Cornejo, Irene Academic achievement Adolescents Children Motor activity School performance The authors gratefully acknowledge the youth, parents, and teachers who participated in this study. The UP&DOWN Study was supported by the DEP 2010-21662-C04-00 grant from the National Plan for Research, Development, and Innovation (R + D + i) MICINN. DM--G is supported by a 'Ramon y Cajal' contract (RYC--2016--20546). IE--C is supported by the Spanish Ministry of Economy and Competitiveness (RTI2018-095284-J-100). AM--M was a recipient of a Jose Castillejo Fellowship from the Spanish Ministry of Science, Innovation, and Universities (CAS19/00265). JS is supported by a Leadership Level 2 Fellowship, National Health and Medical Research Council Australia (APP 1176885). This research was partially funded by "Convocatoria extraordinaria de ayudas a la investigacion. Preparacion, ejecucion y transferencia de conocimiento (convocatoria 2020) de l'Institut de Recerca i Innovacio Educativa (IRIE)". To examine the longitudinal relationships between objectively measured total volume and specific intensities of physical activity (PA) with academic performance in a large sample of youth aged 6-18 years. A longitudinal study of 1046 youth (10.04 ± 3.10 years) from Spain was followed over 2 years. PA (volume and intensity) was measured by accelerometry. Academic performance was assessed through grades reported on the transcript at the end of the academic year (Mathematics, Language, an average of these two core subjects, and grade point average [GPA]). Longitudinal relationships between PA and four indicators of academic performance were examined using covariance and regression analyses, adjusted for a variety of confounders. Youth Quartile 2 for PA volume at baseline obtained better scores than those who participated in Quartiles 1 or 4 volumes of PA in GPA 2 years later (p = 0.006). There were generally no longitudinal associations between specific PA intensities and any of the academic performance indicators (all p > 0.170). However, a change in light PA over 2 years was inversely associated with three academic indicators in youth (βrange, -. 103 to -090; all P < 040). Findings suggest that participants in Quartile 2 volume of PA had a better GPA in comparison with Quartiles 1 and 4 volumes of PA during youth, but there was no association with changes in PA volume over time. PA intensity was generally unrelated to academic performance during youth. However, there was an inverted u-shape relationship between light PA changes and GPA. 2021-10-13T08:01:04Z 2021-10-13T08:01:04Z 2021-08-19 info:eu-repo/semantics/article Muntaner-Mas, A... [et al.]. Objectively measured physical activity and academic performance in school-aged youth: The UP&DOWN longitudinal study. Scand J Med Sci Sports. 2021; 00: 1– 11. [https://doi.org/10.1111/sms.14036] http://hdl.handle.net/10481/70817 10.1111/sms.14036 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Wiley-Blackwell Publishing