Cardiorespiratory Fitness Is Associated with Hard and Light Intensity Physical Activity but Not Time Spent Sedentary in 10–14 Year Old Schoolchildren: The HAPPY Study

Abstract

BackgroundSedentary behaviour is a major risk factor for developing chronic diseases and is associated with low cardiorespiratory fitness in adults. It remains unclear how sedentary behaviour and different physical activity subcomponents are related to cardiorespiratory fitness in children. The purpose of this study was to assess how sedentary behaviour and different physical activity subcomponents are associated with 10–14 year-old schoolchildren's cardiorespiratory fitness.Methods135 schoolchildren (81 girls, 12±1 year) completed 7-day minute-by-minute habitual physical activity monitoring using triaxial accelerometers and undertook a maximal cardiorespiratory fitness test.ResultsAfter controlling for sex, age, ethnicity, socioeconomic status and total wear time, light physical activity (1.5–2.9 METs) was negatively associated (β = −.24, p<.01) and hard physical activity (≥9 METs) positively associated (β = .45, p<.001) with cardiorespiratory fitness. Vigorous and hard physical activity were associated with cardiorespiratory fitness for boys (F = 5.64, p<.01) whereas light, moderate and hard physical activity were associated with physical fitness for girls (F = 10.23, p<.001). No association was found between sedentary time and cardiorespiratory fitness (r = −.13, p>.05). Sedentary to active transitions revealed little variability between cardiorespiratory fitness tertiles.ConclusionsHard physical activity (≥9 METs) holds greater potential for cardiorespiratory fitness compared to physical activity of lower intensities. There was no relationship between sedentary behaviour and cardiorespiratory fitness. These findings suggest that, for children, advice should focus on higher intensity physical activity and not sedentary behaviour as a means to maintain or improve cardiorespiratory fitness. Future research should explore longitudinal relationships between hard physical activity, cardiorespiratory fitness and health parameters.

Socioeconomic gradients in cardiovascular risk in Canadian children and adolescents

“…37,38 This hypothesis is supported by Canadian and other studies that showed that girls in low-SES neighbourhoods engaged in significantly more screen time than did girls who lived in high SES neighbourhoods, a relationship not observed in boys. 39,40 Note that some studies have suggested that organized sport is one of the best ways to encourage vigorous activity in adolescent girls, 41,42 and that vigorous physical activity is the best way to achieve cardiorespiratory fitness. Intervention research on effectively promoting physical fitness to reduce SES gradients in Canadian youth, and especially those in low-SES groups, is needed.…”

Body mass index, cardiorespiratory fitness and cardiometabolic risk factors in youth from Portugal and Mozambique

“…20,22-24, [35][36][37][38] The income inequality observed in Mozambique, especially in Maputo city, even after its economic growth, may impede children from having access or opportunities to buy sports equipment, or to engage in moderate-to-high recreational physical activities offered by organized private sports' clubs. In addition, the reduction in physical activity levels, namely in household chores, subsistence, leisure time and transportation (walk) activities (unpublished data), increases in sedentary time 39 as well as rises in overweight/ obesity prevalences in Mozambican youth 40 in recent decades may explain their lower performance, as physical activity 41 and body size 42,43 are related to cardiorespiratory fitness performance. Differences in cardiometabolic indicators among ethnic groups were previously reported, 44 and a similar result was expected when comparing Mozambican and Portuguese youth.…”

Cardiorespiratory fitness in urban adolescent girls: associations with race and pubertal status

“…Descriptive statistics, including means, standard deviations, frequencies, and percentages, were calculated to describe demographic and PA variables. Previous literature indicates that of the typical PA intensity classifications (sedentary, light, moderate, moderate–vigorous, vigorous), vigorous PA consistently demonstrates the strongest association with fitness (Denton et al, 2013). To verify that vigorous PA was the most appropriate activity variable to use as a covariate in the final analysis, correlations between fitness and time spent sedentary and in light, moderate, moderate-vigorous, and vigorous PA were inspected.…”