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This study examined the associations between CRF, body composition, and health-related habits in 685 children and adolescents (aged 8\u201316 years) who regularly participated in extracurricular sports programs in northeastern Spain. Methods: Participants underwent anthropometric assessments, completed a 20 m shuttle run test to evaluate CRF, and filled out validated questionnaires on physical activity levels, sleep quality, and adherence to the Mediterranean diet. Results: Significant sex differences were observed, with boys achieving higher CRF performance (p &lt; 0.001), primarily associated with greater muscle mass (p &lt; 0.001) and lower body fat percentage (p &lt; 0.001). Age positively correlated with improved CRF (p &lt; 0.001), whereas higher body mass index (p = 0.003) and fat mass (p = 0.020) negatively impacted fitness outcomes. Conclusions: These findings underscore the critical role of physical activity and optimal body composition in promoting cardiorespiratory fitness among youth, emphasizing the importance of targeted interventions to foster healthy behaviors from early childhood. Future research should adopt longitudinal designs to better elucidate the dynamic interactions between lifestyle factors, body composition, and physical fitness throughout childhood and adolescence.<\/jats:p>","DOI":"10.3390\/children12050581","type":"journal-article","created":{"date-parts":[[2025,5,2]],"date-time":"2025-05-02T08:28:11Z","timestamp":1746174491000},"page":"581","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Cardiorespiratory Fitness in Spanish Youth: The Roles of Sex, Age, Body Composition, and Healthy Lifestyle Habits in Cor-School Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-2034-4600","authenticated-orcid":false,"given":"Sa\u00fcl","family":"Aixa-Requena","sequence":"first","affiliation":[{"name":"Human Movement Research Group (RGHM), University of Lleida, Pla\u00e7a de V\u00edctor Siurana, 25003 Lleida, Spain"},{"name":"Faculty of Education, Psychology and Social Work, Department of Specific Didactics, University of Lleida, 25003 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u00c1lvaro","family":"Pano-Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Human Movement Research Group (RGHM), University of Lleida, Pla\u00e7a de V\u00edctor Siurana, 25003 Lleida, Spain"},{"name":"Faculty of Education, Psychology and Social Work, Department of Specific Didactics, University of Lleida, 25003 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3201-3298","authenticated-orcid":false,"given":"Vicen\u00e7","family":"Hern\u00e1ndez-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Human Movement Research Group (RGHM), University of Lleida, Pla\u00e7a de V\u00edctor Siurana, 25003 Lleida, Spain"},{"name":"Faculty of Education, Psychology and Social Work, Department of Specific Didactics, University of Lleida, 25003 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1435-1598","authenticated-orcid":false,"given":"Enric","family":"Conesa-Milian","sequence":"additional","affiliation":[{"name":"Human Movement Research Group (RGHM), University of Lleida, Pla\u00e7a de V\u00edctor Siurana, 25003 Lleida, Spain"},{"name":"Faculty of Education, Psychology and Social Work, Department of Specific Didactics, University of Lleida, 25003 Lleida, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4337-8890","authenticated-orcid":false,"given":"Abraham","family":"Batalla-Gavald\u00e0","sequence":"additional","affiliation":[{"name":"University School of Health and Sport (EUSES), Universitat Rovira i Virgili, 43870 Amposta, Spain"},{"name":"Department of Education and Specific Didactics, Faculty of Humanities and Social Sciences, Universitat Jaume I, Castell\u00f3n de la Plana, 12006 Castell\u00f3n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9286-8453","authenticated-orcid":false,"given":"Jose Vicente","family":"Beltr\u00e1n-Garrido","sequence":"additional","affiliation":[{"name":"Physical Exercise and Performance Research Group, Universidad Cardenal Herrera-CEU, CEU Universities, Castellon de la Plana, 12006 Castell\u00f3n, Spain"},{"name":"Department of Education Sciences, School of Humanities and Communication Sciences, Universidad Cardenal Herrera-CEU, CEU Universities, Castellon de la Plana, 12006 Castell\u00f3n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9304-3709","authenticated-orcid":false,"given":"Isaac","family":"L\u00f3pez-Laval","sequence":"additional","affiliation":[{"name":"Faculty of Health and Sport Science, Department of Physiatry and Nursing, University of Zaragoza, 50009 Huesca, 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Pediatr."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1197","DOI":"10.1249\/MSS.0000000000000901","article-title":"Physical Activity, Fitness, Cognitive Function, and Academic Achievement in Children","volume":"48","author":"Donnelly","year":"2016","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"l4570","DOI":"10.1136\/bmj.l4570","article-title":"Dose-Response Associations between Accelerometry Measured Physical Activity and Sedentary Time and All Cause Mortality: Systematic Review and Harmonised Meta-Analysis","volume":"366","author":"Ekelund","year":"2019","journal-title":"BMJ"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/S2352-4642(19)30323-2","article-title":"Global Trends in Insufficient Physical Activity among Adolescents: A Pooled Analysis of 298 Population-Based Surveys with 1\u00b76 Million Participants","volume":"4","author":"Guthold","year":"2020","journal-title":"Lancet Child. Adolesc. Health"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1016\/S0140-6736(21)01259-9","article-title":"Physical Activity Behaviours in Adolescence: Current Evidence and Opportunities for Intervention","volume":"398","author":"Ekelund","year":"2021","journal-title":"Lancet"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Bonnie, R.J., and Backes, E.P. (2019). The Promise of Adolescence, National Academies Press.","DOI":"10.17226\/25388"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1016\/S0140-6736(23)02750-2","article-title":"Worldwide Trends in Underweight and Obesity from 1990 to 2022: A Pooled Analysis of 3663 Population-Representative Studies with 222 Million Children, Adolescents, and Adults","volume":"403","author":"Phelps","year":"2024","journal-title":"Lancet"},{"key":"ref_8","first-page":"233","article-title":"Differences in the Temporal Trends of Childhood Overweight and Obesity in Spain in the 2011\u20132019 Period by Sex, Age and Socioeconomic Level: Results of the ALADINO Study","volume":"100","year":"2024","journal-title":"An. Pediatr\u00eda"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1016\/S2213-8587(22)00047-X","article-title":"Obesity in Children and Adolescents: Epidemiology, Causes, Assessment, and Management","volume":"10","author":"Jebeile","year":"2022","journal-title":"Lancet Diabetes Endocrinol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"187","DOI":"10.4103\/2249-4863.154628","article-title":"Childhood Obesity: Causes and Consequences","volume":"4","author":"Sahoo","year":"2015","journal-title":"J. Fam. Med. Prim. Care"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1146\/annurev-clinpsy-100219-060201","article-title":"Prevention and Management of Childhood Obesity and Its Psychological and Health Comorbidities","volume":"16","author":"Smith","year":"2020","journal-title":"Annu. Rev. Clin. Psychol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"870","DOI":"10.1111\/joim.13547","article-title":"Pediatric Obesity\u2014Long-term Consequences and Effect of Weight Loss","volume":"292","author":"Marcus","year":"2022","journal-title":"J. Intern. Med."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"196","DOI":"10.3345\/cep.2020.00997","article-title":"The Impacts of Exercise on Pediatric Obesity","volume":"64","author":"Headid","year":"2020","journal-title":"Clin. Exp. Pediatr."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"785","DOI":"10.1016\/S0140-6736(25)00397-6","article-title":"Global, Regional, and National Prevalence of Child and Adolescent Overweight and Obesity, 1990\u20132021, with Forecasts to 2050: A Forecasting Study for the Global Burden of Disease Study 2021","volume":"405","author":"Kerr","year":"2025","journal-title":"Lancet"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1186\/s12966-016-0396-4","article-title":"Variation in Population Levels of Physical Activity in European Children and Adolescents According to Cross-European Studies: A Systematic Literature Review within DEDIPAC","volume":"13","author":"Loyen","year":"2016","journal-title":"Int. J. Behav. Nutr. Phys. Act."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e101","DOI":"10.1161\/CIR.0000000000000866","article-title":"Cardiorespiratory Fitness in Youth\u2014An Important Marker of Health: A Scientific Statement from the American Heart Association","volume":"142","author":"Raghuveer","year":"2020","journal-title":"Circulation"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Osailan, A.M., Elnaggar, R.K., Alsubaie, S.F., Alqahtani, B.A., and Abdelbasset, W.K. (2021). The Association between Cardiorespiratory Fitness and Reported Physical Activity with Sleep Quality in Apparently Healthy Adults: A Cross-Sectional Study. Int. J. Environ. Res. Public Health, 18.","DOI":"10.20944\/preprints202103.0323.v1"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2563","DOI":"10.1249\/MSS.0000000000002418","article-title":"Traditional and New Perspectives on Youth Cardiorespiratory Fitness","volume":"52","author":"Armstrong","year":"2020","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"952","DOI":"10.1001\/jamapediatrics.2020.2400","article-title":"Association of Cardiorespiratory Fitness Levels During Youth with Health Risk Later in Life","volume":"174","author":"Izquierdo","year":"2020","journal-title":"JAMA Pediatr."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"863","DOI":"10.1016\/j.jsams.2024.07.013","article-title":"The Associations between Organized Sport Participation and Physical Fitness and Weight Status Development during Adolescence","volume":"27","author":"Kolunsarka","year":"2024","journal-title":"J. Sci. Med. Sport"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.smrv.2015.07.004","article-title":"The Relationship between Physical Activity and Sleep from Mid Adolescence to Early Adulthood. A systematic review of methodological approaches and meta-analysis","volume":"28","author":"Lang","year":"2016","journal-title":"Sleep Med. Rev."},{"key":"ref_22","first-page":"748","article-title":"Sleep Quality Is Mediated by Physical Activity Level in Adolescents","volume":"63","year":"2023","journal-title":"J. Sports Med. Phys. Fit."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/j.jesf.2024.07.001","article-title":"Mediating Role of Physical Fitness on the Association between Diet and Health-Related Quality of Life in Adolescents","volume":"22","year":"2024","journal-title":"J. Exerc. Sci. Fit."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Zhao, Y., Qu, D., Liang, K., Bao, R., and Chen, S. (2023). Eating Habits Matter for Sleep Difficulties in Children and Adolescents: A Cross-Sectional Study. Front. Pediatr., 11.","DOI":"10.3389\/fped.2023.1108031"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1093\/eurpub\/cky043","article-title":"Associations between Physical Fitness and Adherence to the Mediterranean Diet with Health-Related Quality of Life in Adolescents: Results from the LabMed Physical Activity Study","volume":"28","author":"Evaristo","year":"2018","journal-title":"Eur. J. Public Health"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Aixa-Requena, S., Hern\u00e1ndez-Gonz\u00e1lez, V., Conesa-Milian, E., Batalla-Gavald\u00e0, A., and Reverter-Masia, J. (2024). The COR-School Project: Physical Activity and Cardiometabolic Health in Spanish Youth. Youth, 5.","DOI":"10.3390\/youth5010002"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"873","DOI":"10.1161\/CIR.0b013e31829b5b44","article-title":"Exercise Standards for Testing and Training","volume":"128","author":"Fletcher","year":"2013","journal-title":"Circulation"},{"key":"ref_28","unstructured":"Rowland, T.W. (2018). Cardiopulmonary Exercise Testing in Children and Adolescents, Human Kinetics. [1st ed.]."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"World Medical Association (2013). World Medical Association Declaration of Helsinki: Ethical Principles for Medical Research Involving Human Subjects. JAMA, 310, 2191\u20132194.","DOI":"10.1001\/jama.2013.281053"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1016\/1054-139X(93)90004-9","article-title":"A Self-Administered Rating Scale for Pubertal Development","volume":"14","author":"Carskadon","year":"1993","journal-title":"J. Adolesc. Health"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1136\/adc.51.3.170","article-title":"Clinical Longitudinal Standards for Height, Weight, Height Velocity, Weight Velocity, and Stages of Puberty","volume":"51","author":"Tanner","year":"1976","journal-title":"Arch. Dis. Child."},{"key":"ref_32","unstructured":"Esparza-Ros, F., Vaquero-Crist\u00f3bal, R., and Marfell-Jones, M. (2019). Protocolo Internacional Para la Valoraci\u00f3n Antropom\u00e9trica, Sociedad Internacional para el Avance de la Cineantropometr\u00eda, ISAK."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"GBD 2015 Obesity Collaborators, Afshin, A., Forouzanfar, M.H., Reitsma, M.B., Sur, P., Estep, K., Lee, A., Marczak, L., Mokdad, A.H., and Moradi-Lakeh, M. (2017). Health Effects of Overweight and Obesity in 195 Countries over 25 Years. N. Engl. J. Med., 377, 13\u201327.","DOI":"10.1056\/NEJMoa1614362"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"738","DOI":"10.1001\/jama.2024.11809","article-title":"Obesity in Adolescents","volume":"332","author":"Kelly","year":"2024","journal-title":"JAMA"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/BF00428958","article-title":"A Maximal Multistage 20-m Shuttle Run Test to Predict VO2 Max","volume":"49","author":"Lambert","year":"1982","journal-title":"Eur. J. Appl. Physiol. Occup. Physiol."},{"key":"ref_36","first-page":"1210","article-title":"ALPHA-Fitness test battery: Health-related field-based fitness tests assessment in children and adolescents","volume":"26","author":"Ruiz","year":"2011","journal-title":"Nutr. Hosp."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1136\/bjsm.2010.075341","article-title":"Field-Based Fitness Assessment in Young People: The ALPHA Health-Related Fitness Test Battery for Children and Adolescents","volume":"45","author":"Ruiz","year":"2011","journal-title":"Br. J. Sports Med."},{"key":"ref_38","first-page":"536","article-title":"Criterion-Related Validity of the 20-M Shuttle Run Test for Estimating Fitness: A Meta-Analysis","volume":"14","author":"Viciana","year":"2015","journal-title":"J. Sports Sci. Med."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"101012","DOI":"10.1016\/j.jshs.2024.101012","article-title":"The Youth Fitness International Test (YFIT) Battery for Monitoring and Surveillance among Children and Adolescents: A Modified Delphi Consensus Project with 169 Experts from 50 Countries and Territories","volume":"14","author":"Ortega","year":"2024","journal-title":"J. Sport Health Sci."},{"key":"ref_40","first-page":"139","article-title":"Fiabilidad de La Versi\u00f3n Espa\u00f1ola Del Cuestionario de Actividad F\u00edsica PAQ-C\/Reliability of the Spanish Version of Questionnaire of Physical Activity PAQ-C","volume":"65","year":"2017","journal-title":"Rev. Int. Med. Cienc. Act. F\u00eds. Deport."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1590\/S1135-57272009000300008","article-title":"Fiabilidad y validez del cuestionario de actividad f\u00edsica PAQ-A en adolescentes espa\u00f1oles","volume":"83","author":"Pozo","year":"2009","journal-title":"Rev. Esp. Salud Publica"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Marasso, D., Lupo, C., Collura, S., Rainoldi, A., and Brustio, P.R. (2021). Subjective versus Objective Measure of Physical Activity: A Systematic Review and Meta-Analysis of the Convergent Validity of the Physical Activity Questionnaire for Children (PAQ-C). Int. J. Environ. Res. Public Health, 18.","DOI":"10.3390\/ijerph18073413"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Voss, C., Dean, P.H., Gardner, R.F., Duncombe, S.L., and Harris, K.C. (2017). Validity and Reliability of the Physical Activity Questionnaire for Children (PAQ-C) and Adolescents (PAQ-A) in Individuals with Congenital Heart Disease. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0175806"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1186\/2049-3258-72-47","article-title":"Reliability and Validity of the Dutch Physical Activity Questionnaires for Children (PAQ-C) and Adolescents (PAQ-A)","volume":"72","author":"Bervoets","year":"2014","journal-title":"Arch. Public Health"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/0165-1781(89)90047-4","article-title":"The Pittsburgh Sleep Quality Index: A New Instrument for Psychiatric Practice and Research","volume":"28","author":"Buysse","year":"1989","journal-title":"Psychiatry Res."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"e22","DOI":"10.1037\/pas0000128","article-title":"The Pittsburgh Sleep Quality Index: Validity and Factor Structure in Young People","volume":"27","author":"Racine","year":"2015","journal-title":"Psychol. Assess."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1111\/joim.13333","article-title":"The Mediterranean Diet and Health: A Comprehensive Overview","volume":"290","author":"Willett","year":"2021","journal-title":"J. Intern. Med."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"931","DOI":"10.1079\/PHN2004556","article-title":"Food, Youth and the Mediterranean Diet in Spain. Development of KIDMED, Mediterranean Diet Quality Index in Children and Adolescents","volume":"7","author":"Ribas","year":"2004","journal-title":"Public Health Nutr."},{"key":"ref_49","first-page":"2390","article-title":"KIDMED Test; Prevalence of Low Adherence to the Mediterranean Diet in Children and Young; a Systematic Review","volume":"32","author":"Nissensohn","year":"2015","journal-title":"Nutr. Hosp."},{"key":"ref_50","unstructured":"Jamovi (2025). The Jamovi project Jamovi 2025, The Jamovi Project."},{"key":"ref_51","unstructured":"Gallucci, M., and Love, J. (2025, March 19). GAMLj: General Analyses for the Linear Model in Jamovi. Comput. Softw. Available online: https:\/\/gamlj.github.io\/."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1545","DOI":"10.1136\/bjsports-2016-095987","article-title":"International Normative 20\u2005m Shuttle Run Values from 1\u2005142\u2005026 Children and Youth Representing 50 Countries","volume":"51","author":"Tomkinson","year":"2017","journal-title":"Br. J. Sports Med."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"i67","DOI":"10.1093\/eurpub\/ckac075","article-title":"Differences in Body Composition and Physical Fitness Parameters among Prepubertal and Pubertal Children Engaged in Extracurricular Sports: The Active Health Study","volume":"32","author":"Gallardo","year":"2022","journal-title":"Eur. J. Public Health"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1510","DOI":"10.1080\/02640414.2014.906046","article-title":"Physical Fitness Percentiles for Portuguese Children and Adolescents Aged 10\u201318 Years","volume":"32","author":"Santos","year":"2014","journal-title":"J. Sports Sci."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Zhang, P.-P., Wang, Y.-X., Gu, J.-Y., Xu, M., Zhou, Y., Wang, H.-J., Lau, P.W.C., Wang, H., and Li, L. (2024). Cardiorespiratory Fitness Attenuates the Association between Fatness and Cardiometabolic Risk in Chinese Children. Front. Endocrinol., 15.","DOI":"10.3389\/fendo.2024.1361447"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"279","DOI":"10.21101\/cejph.a7645","article-title":"Normative-Referenced Values for Health-Related Fitness among Czech Youth: Physical Fitness Data from the Study IPEN Adolescent Czech Republic","volume":"31","author":"Suchomel","year":"2023","journal-title":"Cent. Eur. J. Public Health"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1439","DOI":"10.1519\/JSC.0000000000000756","article-title":"Long-Term Athletic Development\u2014Part 1","volume":"29","author":"Lloyd","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1136\/bjsports-2016-096224","article-title":"International Variability in 20 m Shuttle Run Performance in Children and Youth: Who Are the Fittest from a 50-Country Comparison? A Systematic Literature Review with Pooling of Aggregate Results","volume":"52","author":"Lang","year":"2018","journal-title":"Br. J. Sports Med."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"2577","DOI":"10.1007\/s40279-018-0974-5","article-title":"Cardiorespiratory Fitness in Childhood and Adolescence Affects Future Cardiovascular Risk Factors: A Systematic Review of Longitudinal Studies","volume":"48","author":"Mintjens","year":"2018","journal-title":"Sports Med."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"2230","DOI":"10.4081\/jphr.2021.2230","article-title":"Purbodjati Body Mass Index, Physical Activity, and Physical Fitness of Adolescence","volume":"10","author":"Dewi","year":"2021","journal-title":"J. Public Health Res."},{"key":"ref_61","doi-asserted-by":"crossref","unstructured":"Moran, C.A., Peccin, M.S., Bombig, M.T., Pereira, S.A., and Dal Corso, S. (2017). Performance and Reproducibility on Shuttle Run Test between Obese and Non-Obese Children: A Cross-Sectional Study. BMC Pediatr., 17.","DOI":"10.1186\/s12887-017-0825-9"},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Wang, Q., Guo, H., Chen, S., Ma, J., and Kim, H. (2022). The Association of Body Mass Index and Fat Mass with Health-Related Physical Fitness among Chinese Schoolchildren: A Study Using a Predictive Model. Int. J. Environ. Res. Public Health, 20.","DOI":"10.3390\/ijerph20010355"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"2574","DOI":"10.1249\/MSS.0000000000002424","article-title":"Skeletal Muscle Mass Is Linked to Cardiorespiratory Fitness in Youth","volume":"52","author":"Witekind","year":"2020","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"2345","DOI":"10.1007\/s00431-023-04887-4","article-title":"Relationships of BMI, Muscle-to-Fat Ratio, and Handgrip Strength-to-BMI Ratio to Physical Fitness in Spanish Children and Adolescents","volume":"182","author":"Haapala","year":"2023","journal-title":"Eur. J. Pediatr."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Raine, L.B., Erickson, K.I., Grove, G., Watrous, J.N.H., McDonald, K., Kang, C., Jakicic, J.M., Forman, D.E., Kramer, A.F., and Burns, J.M. (2023). Cardiorespiratory Fitness Levels and Body Mass Index of Pre-Adolescent Children and Older Adults during the COVID-19 Pandemic. Front. Public Health, 10.","DOI":"10.3389\/fpubh.2022.1052389"},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Chen, G., Chen, J., Liu, J., Hu, Y., and Liu, Y. (2022). Relationship between Body Mass Index and Physical Fitness of Children and Adolescents in Xinjiang, China: A Cross-Sectional Study. BMC Public Health, 22.","DOI":"10.1186\/s12889-022-14089-6"},{"key":"ref_67","doi-asserted-by":"crossref","unstructured":"Lopes, V.P., Cossio-Bola\u00f1os, M., G\u00f3mez-Campos3, R., de Arruda, M., Hespanhol, J.E., and Rodrigues, L.P. (2017). Linear and Nonlinear Relationships between Body Mass Index and Physical Fitness in Brazilian Children and Adolescents. Am. J. Hum. Biol., 29.","DOI":"10.1002\/ajhb.23035"},{"key":"ref_68","doi-asserted-by":"crossref","unstructured":"Messing, S., R\u00fctten, A., Abu-Omar, K., Ungerer-R\u00f6hrich, U., Goodwin, L., Burlacu, I., and Gediga, G. (2019). How Can Physical Activity Be Promoted Among Children and Adolescents? A Systematic Review of Reviews Across Settings. Front. Public Health, 7.","DOI":"10.3389\/fpubh.2019.00055"},{"key":"ref_69","doi-asserted-by":"crossref","unstructured":"Wu, X.Y., Han, L.H., Zhang, J.H., Luo, S., Hu, J.W., and Sun, K. (2017). The Influence of Physical Activity, Sedentary Behavior on Health-Related Quality of Life among the General Population of Children and Adolescents: A Systematic Review. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0187668"},{"key":"ref_70","doi-asserted-by":"crossref","unstructured":"Mielgo-Ayuso, J., Aparicio-Ugarriza, R., Castillo, A., Ruiz, E., \u00c1vila, J.M., Aranceta-Batrina, J., Gil, \u00c1., Ortega, R.M., Serra-Majem, L., and Varela-Moreiras, G. (2016). Physical Activity Patterns of the Spanish Population Are Mostly Determined by Sex and Age: Findings in the ANIBES Study. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0149969"},{"key":"ref_71","doi-asserted-by":"crossref","unstructured":"Polo-Recuero, B., Ord\u00f3\u00f1ez-Dios, A., Rojo-Tirado, M.\u00c1., and Lorenzo, A. (2023). Do You Want to Increase Physical Activity in Adolescents? A School-Based Physical Activity Program Could Be an Efficient Way. Children, 10.","DOI":"10.3390\/children10101641"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1159\/000348673","article-title":"Energy Consumption, Body Composition and Physical Activity Levels in 11- to 13-Year-Old Spanish Children","volume":"63","author":"Cordova","year":"2013","journal-title":"Ann. Nutr. Metab."},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Kolb, S., Burchartz, A., Klos, L., Jekauc, D., Niessner, C., and Woll, A. (2025). Association between Physical Activity and Physical Health in German Children and Adolescents\u2014Results from the MoMo Longitudinal Study. BMC Public Health, 25.","DOI":"10.1186\/s12889-025-21684-w"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1080\/02640414.2021.1994728","article-title":"Associations between Spanish Children\u2019s Physical Activity and Physical Fitness with Lean Body Mass: The CALINA Study","volume":"40","author":"Iglesia","year":"2022","journal-title":"J. Sports Sci."},{"key":"ref_75","doi-asserted-by":"crossref","unstructured":"Naja, F., Hasan, H., Khadem, S.H., Buanq, M.A., Al-Mulla, H.K., Aljassmi, A.K., and Faris, M.E. (2022). Adherence to the Mediterranean Diet and Its Association with Sleep Quality and Chronotype Among Youth: A Cross-Sectional Study. Front. Nutr., 8.","DOI":"10.3389\/fnut.2021.805955"},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.clnesp.2021.07.012","article-title":"The Association between Dietary Patterns and Quality and Duration of Sleep in Children and Adolescents: A Systematic Review","volume":"45","author":"Alibabaei","year":"2021","journal-title":"Clin. Nutr. ESPEN"},{"key":"ref_77","doi-asserted-by":"crossref","unstructured":"Stojanovi\u0107, S., Andrieieva, O., and Trajkovi\u0107, N. (2024). Associations between Number of Steps and Health Outcomes in Children and Adolescents: A Systematic Review and Meta-Analysis. BMC Public Health, 24.","DOI":"10.1186\/s12889-024-20835-9"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"755","DOI":"10.1007\/s13679-024-00589-6","article-title":"Diet Quality Scores, Obesity and Metabolic Syndrome in Children and Adolescents: A Systematic Review and Meta-Analysis","volume":"13","author":"Mahmood","year":"2024","journal-title":"Curr. Obes. Rep."},{"key":"ref_79","doi-asserted-by":"crossref","unstructured":"Bacaro, V., Carpentier, L., and Crocetti, E. (2023). Sleep Well, Study Well: A Systematic Review of Longitudinal Studies on the Interplay between Sleep and School Experience in Adolescence. Int. J. Environ. Res. Public Health, 20.","DOI":"10.3390\/ijerph20064829"},{"key":"ref_80","doi-asserted-by":"crossref","unstructured":"Fiedler, J., Eckert, T., Burchartz, A., Woll, A., and Wunsch, K. (2021). Comparison of Self-Reported and Device-Based Measured Physical Activity Using Measures of Stability, Reliability, and Validity in Adults and Children. 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