The Relationship between Socioeconomic Status, Family Income, and Measures of Muscular and Cardiorespiratory Fitness in Colombian Schoolchildren

Gavin R.H. Sandercock, Felipe Lobelo, Jorge E. Correa-Bautista, Gustavo Tovar, Daniel Dylan Cohen, Gundi Knies, Robinson Ramírez-Vélez
2017 Journal of Pediatrics  
Objective To determine the associations between socioeconomic status (SES) and physical fitness in a sample of Colombian youth. Study design Prueba SER is cross-sectional survey of schoolchildren in Bogota, Colombia. Mass, stature, muscular fitness (standing long-jump, handgrip), and cardiorespiratory fitness (20-m shuttle run) were measured in 52 187 schoolchildren 14-16 years of age. Area-level SES was categorized from 1 (very low) to 4 (high) and parentreported family income was categorized
more » ... s low, middle, or high. Results Converting measures into z scores showed stature, muscular, and cardiorespiratory fitness were significantly (z = 0.3-0.7) below European values. Children in the mid-and high SES groups jumped significantly further than groups with very low SES. Differences were independent of sex but became nonsignificant when adjusted for anthropometric differences. Participants in the mid-SES and high-SES groups had better handgrip scores when adjusted for body dimension. There were, however, no significant between-group differences in cardiorespiratory fitness, which was strongly clustered by school and significantly greater in students from private schools. Conclusions Area-level SES is associated with measures of muscular fitness in Colombian schoolchildren. These associations were largely explained by the large differences in body dimensions observed between SES groups. When area-level SES is considered, there was no evidence that family income influenced fitness. The clustering of outcomes reaffirms the potential importance of schools and area-level factors in promoting fitness through opportunities for physical activity. Interventions implemented in schools, can improve academic attainment; a factor likely to be important in promoting the social mobility of children from poorer families. (J Pediatr 2017;■■:■■-■■). See editorial, p ••• T he negative gradient between socioeconomic status (SES) and prevalence of noncommunicable disease in adulthood has prompted investigation of potential foundations based in childhood. 1 Because children rarely present with clinical manifestations of chronic disease, risk factors that track from early life into adulthood are used as surrogate indicators future health status. 1,2 Excess adiposity and poor physical fitness and low cardiorespiratory or muscular fitness in particular are associated independently with poor cardiometabolic health in children. 2 Fluctuations in fitness predominantly are the result of changes in habitual physical activity, modulated by genetic and early life (epigenetic) factors. The relatively poor tracking of physical activity from childhood into adulthood hampers attempts to determine the associations between childhood physical activity and adult health. 3 Compared with physical activity, physical fitness is a more potent indicator of cardiometabolic health status, 2-4 which also tracks more strongly from childhood into adulthood. 3 Children from families with high and middle SES designations tend to perform better on physical fitness tests than those from low SES backgrounds. 5-7 Reports of the association between SES and fitness appear to vary according to the method of fitness assessment 8 and the classification of SES 9 used. Far less is known of the association between SES and fitness in low-to middle-income countries. 10 Petroski et al 10 found Brazilian children from families of low SES were 40% less likely to meet criterion-referenced standards for multicomponent fitness. Urban-dwelling youth from Ecuador 11 and Chile 12 were found to be fitter than those from rural
doi:10.1016/j.jpeds.2016.12.058 pmid:28161198 fatcat:wkr7h4spuzbbxgls7vkx2obsna