The main purpose of the study was to analyze secular trends of health-related physical fitness in 7-14-year-old Croatian children and adolescents from 1999 and 2014. In this observational cross-sectional study, we recruited 5077 children and adolescents between ages 11 and 14 (50.8% girls) from five primary schools located in the capital city of Zagreb. Physical fitness performance was tested from 1999 until 2014. Physical fitness performance included: (1) body-mass index (measure of body size), (2) standing broad jump (measure of lower-body power), (3) polygon backwards (measure of general coordination and agility), (4) sit-ups in 60 s (measure of upper-body strength), (5) sit-and-reach test (measure of flexibility) and (6) 6-min run test (measure of cardiorespiratory fitness). Boys performed better in all physical fitness tests, except for sit-and-reach test (p < 0.001). In boys, between 1999 and 2014, body size, upper-body strength and coordination/agility increased, while flexibility, lower-body power and cardiorespiratory fitness decreased. During the same period, girls experienced an increase in body size, lower-body power, upper-body strength, coordination/agility and flexibility, while cardiorespiratory fitness decreased. This study shows that cardiorespiratory fitness, flexibility and coordination/agility decrease, while upper-body strength increases in both sexes. These findings should serve as an avenue for national monitoring system to screen and track biological development in children and adolescents.

Department of Educational Studies Faculty of Teacher Education University of Rijeka Rijeka Croatia

Department of General and Applied Kinesiology Faculty of Kinesiology University of Zagreb Horvaćanski zavoj 15 Zagreb Croatia

Department of Sport Motorics and Methodology in Kinanthropology Faculty of Sports Studies Masaryk University Brno Czech Republic

Zobrazit více v PubMed

Ortega FB, Ruiz JR, Castillo MJ, Sjöström M. Physical fitness in childhood and adolescence: A powerful marker of health. Int. J. Obes. (Lond) 2007;32:1–11. doi: 10.1038/sj.ijo.0803774. PubMed DOI

Hamer M, O’Donovan G, Batty GD, Stamatakis E. Estimated cardiorespiratory fitness in childhood and cardiometabolic health in adulthood: 1970 British Cohort Study. Scand. J. Med. Sci. Sports. 2020;30:923–938. doi: 10.1111/sms.13637. PubMed DOI PMC

Ruiz JR, et al. Predictive validity of health-related fitness in youth: A systematic review. Br. J. Sports Med. 2009;43:99–932. doi: 10.1136/bjsm.2008.056499. PubMed DOI

Antero-Jacquemin J, et al. The heart of the matter: Years-saved from cardiovascular and cancer deaths in an elite athlete cohort with over a century of follow-up. Eur. J. Epidemiol. 2018;33:531–543. doi: 10.1007/s10654-018-0401-0. PubMed DOI

Myers J, et al. Exercise capacity and mortality among men referred for exercise testing. N. Engl. J. Med. 2002;346:793–801. doi: 10.1056/NEJMoa011858. PubMed DOI

Timpka S, et al. Muscle strength in adolescent men and risk of cardiovascular disease events and mortality in middle age: A prospective cohort study. BMC Med. 2014;12:62. doi: 10.1186/1741-7015-12-62. PubMed DOI PMC

Lee CD, Blair SN, Jackson AS. Cardiorespiratory fitness, body composition, and all-cause and cardiovascular disease mortality in men. Am. J. Clin. Nutr. 1999;69:373–380. doi: 10.1093/ajcn/69.3.373. PubMed DOI

Kuwahara K, et al. Association of cardiorespiratory fitness and overweight with risk of type 2 diabetes in Japanese men. PLoS One. 2014;9:e98508. doi: 10.1371/journal.pone.0098508. PubMed DOI PMC

Högström G, et al. Risk factors assessed in adolescence and the later risk of stroke in men: A 33-year follow-up study. Cerebrovasc. Dis. 2015;39:63–71. doi: 10.1159/000369960. PubMed DOI

Potočnik ŽL, Jurak G, Starc G. Secular trends of physical fitness in twenty-five birth cohorts of Slovenian children: A population-based study. Front. Public Health. 2020;8:561273. doi: 10.3389/fpubh.2020.561273. PubMed DOI PMC

Tomkinson GR, Olds TS, Borms J. Who are the Eurofittest? Med. Sport. Sci. 2007;50:104–128. doi: 10.1159/000101355. PubMed DOI

Venckunas T, et al. Secular trends in physical fitness and body size in Lithuanian children and adolescents between 1992 and 2012. J. Epidemiol. Community Health. 2017;71:181–187. doi: 10.1136/jech-2016-207307. PubMed DOI

Malina RM. Secular trends in growth, maturation and physical performance: A review. Anthropol. Rev. 2004;67:3–31.

Wedderkopp N, et al. Secular trends in physical fitness and obesity in Danish 9-year-old girls and boys: Odense School Child Study and Danish substudy of the European Youth Heart Study. Scand. J. Med. Sci. Sports. 2004;14:150–155. doi: 10.1111/j.1600-0838.2004.00365.x. PubMed DOI

Malina RM. Physical fitness of children and adolescents in the United States: Status and secular change. Med. Sport. Sci. 2007;50:67–90. doi: 10.1159/000101076. PubMed DOI

Møller NC, et al. Secular trends in cardiorespiratory fitness and body mass index in Danish children: The European Youth Heart Study. Scand. J. Med. Sci. Sports. 2007;17:331–339. PubMed

Stratton G, et al. Cardiorespiratory fitness and body mass index of 9–11-year-old English children: A serial cross-sectional study from 1998 to 2004. Int. J. Obes. 2007;31:1172–1178. doi: 10.1038/sj.ijo.0803562. PubMed DOI

Tomkinson GR, Olds TS. Secular changes in pediatric aerobic fitness test performance: The global picture. Med. Sport. Sci. 2007;50:46–66. doi: 10.1159/000101075. PubMed DOI

Sandercock G, et al. Ten-year secular declines in the cardiorespiratory fitness of affluent English children are largely independent of changes in body mass index. Arch. Dis. Child. 2010;95:46–57. doi: 10.1136/adc.2009.162107. PubMed DOI

Runhaar J, et al. Motor fitness in Dutch youth: Differences over a 26-year period (1980–2006) J. Sci. Med. Sport. 2010;13:323–328. doi: 10.1016/j.jsams.2009.04.006. PubMed DOI

Dos Santos FK, et al. Secular trends in physical fitness of Mozambican school-aged children and adolescents. Am. J. Hum. Biol. 2015;27:206–206. PubMed

Tyler R, et al. Ten-year secular changes in selected health and fitness parameters of 10–11 years old Swansea school children-2003–2013. Adv. Obes. Weight Manag. Control. 2015;3:267–271.

Costa AM, et al. Secular trends in anthropometrics and physical fitness of young Portuguese school-aged children. Acta Med. Portuguesa. 2017;30:108–114. doi: 10.20344/amp.7712. PubMed DOI

Spengler S, et al. Trends in motor performance of first graders: A comparison of cohorts from 2006 to 2015. Front. Pediatr. 2017;5:206. doi: 10.3389/fped.2017.00206. PubMed DOI PMC

Aaberge K, Mamen A. A comparative study of fitness levels among Norwegian youth in 1988 and 2001. Sports. 2019;7:50. doi: 10.3390/sports7020050. PubMed DOI PMC

Sandercock GR, Cohen DD. Temporal trends in muscular fitness of English 10-year-olds 1998–2014: An allometric approach. J. Sci. Med. Sport. 2019;22:201–205. doi: 10.1016/j.jsams.2018.07.020. PubMed DOI

Kocić J, et al. Muscle strength test performance changes over time in Serbian children. Acta Med. Medianae. 2019;58:154–160.

Fraser BJ, et al. The great leap backward: Changes in the jumping performance of Australian children aged 11–12-years between 1985 and 2015. J. Sports Sci. 2019;37:748–754. doi: 10.1080/02640414.2018.1523672. PubMed DOI

Shigaki GB, et al. Secular trend of physical fitness indicators related to health in children. J. Hum. Growth Dev. 2019;29:381–389. doi: 10.7322/jhgd.v29.9537. DOI

Gaya AR, et al. Temporal trends in physical fitness and obesity among Brazilian children and adolescents between 2008 and 2014. J. Hum. Sport. Exerc. 2019;15:549–558. doi: 10.14198/jhse.2020.153.07. DOI

Dong Y, et al. Trends in physical fitness, growth, and nutritional status of Chinese children and adolescents: A retrospective analysis of 1.5 million students from six successive national surveys between 1985 and 2014. Lancet Child. Adolesc. Health. 2019;3:871–880. doi: 10.1016/S2352-4642(19)30302-5. PubMed DOI

Colley RC, et al. Trends in physical fitness among Canadian children and youth. Health Rep. 2019;30:3–13. PubMed

Bi C, Zhang F, Gu Y, Song Y, Cai X. Secular trend in the physical fitness of Xinjiang children and adolescents between 1985 and 2014. Int. J. Environ. Res. Public Health. 2020;17:2195. doi: 10.3390/ijerph17072195. PubMed DOI PMC

Hanssen-Doose A, et al. Population-based trends in physical fitness of children and adolescents in Germany, 2003–2017. Eur. J. Sport Sci. 2020 doi: 10.1080/17461391.2020.1793003. PubMed DOI

Pinoniemi BK, et al. Temporal trends in the standing broad jump performance of United States children and adolescents. Res. Q. Exerc. Sport. 2020 doi: 10.1080/02701367.2019.1710446. PubMed DOI

Eberhardt T, et al. Secular trends in physical fitness of children and adolescents: A review of large-scale epidemiological studies published after 2006. Int. J. Environ. Res. Public Health. 2020;17:5671. doi: 10.3390/ijerph17165671. PubMed DOI PMC

Csányi T, et al. Overview of the Hungarian national youth fitness study. Res. Q. Exerc. Sport. 2015;86:3–12. doi: 10.1080/02701367.2015.1042823. PubMed DOI PMC

Henriques-Neto D, et al. Test-retest reliability of physical fitness tests among young athletes: the FITescola® battery. Clin. Physiol. Funct. Imaging. 2020;40:173–182. doi: 10.1111/cpf.12624. PubMed DOI

Joensuu L, et al. Objectively measured physical activity, body composition and physical fitness: Cross-sectional associations in 9-to 15-year-old children. Eur. J. Sport. Sci. 2018;18:882–892. doi: 10.1080/17461391.2018.1457081. PubMed DOI

Radman I, Sorić M, Mišigoj-Duraković M. Prevalence of key modifiable cardiovascular risk factors among urban adolescents: The CRO-PALS study. Int. J. Environ. Res. Public Health. 2020;17:3162. doi: 10.3390/ijerph17093162. PubMed DOI PMC

World Health Association World Medical Association Declaration of Helsinki. Ethical principles for medical research involving human subjects. Bull. World Health Organ. 2001;79:373–374. PubMed PMC

Štefan L, Paradžik P, Sporiš G. Sex and age correlations of reported and estimated physical fitness in adolescents. PLoS One. 2019;14:e0219217. doi: 10.1371/journal.pone.0219217. PubMed DOI PMC

Sekulić D, et al. Judo training is more effective for fitness development. Pediatr. Exerc. Sci. 2006;18:329–338. doi: 10.1123/pes.18.3.329. DOI

PCPFS (President's Council on Physical Fitness and Sports). The president's challenge physical fitness test: V-sit reach. 2012. https://www.presidentschallenge.org/challenge/physical/activities/v-sit-reach.shtml. Assessed 29 Oct 2020.

Dencker M, et al. Daily physical activity and its relation to aerobic fitness in children aged 8–11 years. Eur. J. Appl. Physiol. 2006;96:587–592. doi: 10.1007/s00421-005-0117-1. PubMed DOI

Kalman M, et al. Secular trends in moderate-to-vigorous physical activity in 32 countries from 2002 to 2010: A cross-national perspective. Eur. J. Public Health. 2015;25:37–40. doi: 10.1093/eurpub/ckv024. PubMed DOI

Vollbekiene V, Griciūte A. Health-related physical fitness among schoolchildren in Lithuania: A comparison from 1992 to 2002. Scand. J. Public Health. 2007;35:235–242. doi: 10.1080/14034940601160649. PubMed DOI

Albon HM, Hamlin MJ, Ross JJ. Secular trends and distributional changes in health and fitness performance variables of 10–14-year-old children in New Zealand between 1991 and 2003. Br. J. Sports Med. 2010;44:263–269. doi: 10.1136/bjsm.2008.047142. PubMed DOI

Huotari PRT, et al. Secular trends in muscular fitness among Finnish adolescents. Scand. J. Public Health. 2010;38:739–747. doi: 10.1177/1403494810384425. PubMed DOI

Dollman J, Olds TS. Secular changes in fatness and fat distribution in Australian children matched for body size. Int. J. Pediatr. Obes. 2006;1:109–113. doi: 10.1080/17477160600684260. PubMed DOI

Normative values of cardiorespiratory fitness in Croatian children and adolescents

Associations between Fat Mass and Fat Free Mass with Physical Fitness in Adolescent Girls: A 3-Year Longitudinal Study

Tracking of health-related physical fitness in adolescent girls: a 3-year follow-up study

Defining Optimal Cut-Points for Cardiorespiratory Fitness Associated With Overweight/Obesity in Children: A School-Based Study