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- Kwak, Lydia, et al.
(författare)
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Associations between physical activity, fitness, and academic achievement.
- 2009
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Ingår i: Journal of Pediatrics. - : Elsevier BV. - 0022-3476 .- 1097-6833. ; 155:6, s. 914-918.e1
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To explore the associations between objectively assessed intensity levels of physical activity and academic achievement and test whether cardiovascular fitness mediates the association between physical activity and academic achievement.STUDY DESIGN: Cross-sectional data were gathered in Swedish 9th-grade students (n = 232; mean age = 16 years; 52% girls). School grades, pubertal phase, skinfold thickness, cardiovascular fitness, and physical activity were measured objectively. Mother's education, family structure, and parental monitoring were self-reported. Data were analyzed with linear regression analyses.RESULTS: After controlling for confounding factors, academic achievement was associated with vigorous physical activity in girls (beta = .30, P < .01; explained variance of the model 26%), which remained after inclusion of fitness (beta = .23, P < .05; explained variance 29%). The association was not mediated by fitness. In boys, academic achievement was associated with pubertal phase (beta = .25, P < .05). After inclusion of fitness, it was only associated with fitness (beta = .25, P < .05; explained variance of the model 30%).CONCLUSION: In girls, academic achievement was associated with vigorous physical activity and not mediated by fitness, whereas in boys only fitness was associated with academic achievement. Further studies are necessary to investigate the potential longitudinal effect of vigorous physical activity on academic achievement, the role of fitness herein and the implications of these findings for schools.
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| 2. |
- Ortega, Francisco B., et al.
(författare)
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Cardiovascular fitness modifies the associations between physical activity and abdominal adiposity in children and adolescents : The European Youth Heart Study
- 2010
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Ingår i: British Journal of Sports Medicine. - London, United Kingdom : BMJ Publishing Group Ltd. - 0306-3674 .- 1473-0480. ; 44:4, s. 256-262
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine the associations between physical activity (PA) and abdominal adiposity, as measured by waist circumference, in children and adolescents, and to test whether cardiovascular fitness (CVF) modifies these associations.Methods: PA components were measured by accelerometry in 1075 individuals aged 9 or 15 years old. CVF was measured by a maximal cycling test. Self-reported maternal educational level, body mass index, children's birth weight and television viewing were used as confounders.Results: Linear regression did not show any association between the PA variables and waist circumference, after controlling for sex, age and height. When stratifying by CVF level (low/high), time spent at vigorous PA was inversely associated with waist circumference (p≤0.05) in the low CVF group. Unexpectedly, in the high CVF group, the PA variables were positively associated with waist circumference (p≤0.05). In both groups, the results were unchanged after controlling for the confounders. CVF was inversely associated with waist circumference, after controlling for all PA variables (p≤0.01) and confounders (p≤0.01).Conclusion: CVF is inversely associated with abdominal adiposity and seems to modify the associations between PA and abdominal adiposity. In low-fit children and adolescents, time spent in vigorous PA seems to be the key component linked to abdominal adiposity. This finding should be considered in further development of lifestyle intervention strategies. The results found in the high-fit group need to be confirmed.
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| 3. |
- Rizzo, Nico S., et al.
(författare)
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Relationship of physical activity, fitness, and fatness with clustered metabolic risk in children and adolescents : the European youth heart study
- 2007
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Ingår i: The Journal of Pediatrics. - St. Louis, Mo : Mosby. - 0022-3476 .- 1097-6833. ; 150:4, s. 388-394
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To examine the associations of physical activity (PA) at different levels and intensities and cardiorespiratory fitness (CRF) with a clustering of metabolic risk factors in children and adolescents with special consideration of body fat. Study design Total PA and intensity levels were measured by accelerometry in children (9 years, n = 273) and adolescents (15 years, n = 256). CRF was measured with a maximal ergometer bike test. Measured outcomes included fasting insulin, glucose, triglycerides, total and high-density lipoprotein cholesterol, blood pressure, and body fat. A metabolic risk score (MRS) was computed as the mean of the standardized outcome scores. A “non-obesity-MRS” was computed omitting body fat from the MRS. Analysis of variance and multiple regressions were used in the analysis. Results Total and vigorous PA was inversely significantly associated with MRS in adolescent girls, the group with lowest PA, becoming insignificant when CRF was introduced in the analysis. Significant regression coefficients of total PA and CRF on non-obesity–MRS diminished when body fat was entered in the analysis. Conclusions CRF is more strongly correlated to metabolic risk than total PA, whereas body fat appears to have a pivotal role in the association of CRF with metabolic risk.
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| 4. |
- Ruiz, Jonatan R., et al.
(författare)
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High cardiovascular fitness is associated with low metabolic risk score in children : the European Youth Heart Study
- 2007
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Ingår i: Pediatric Research. - Baltimore, Md : Williams and Wilkins Co. - 0031-3998 .- 1530-0447. ; 61:3, s. 350-355
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to examine the associations of cardiovascular fitness (CVF) with a clustering of metabolic risk factors in children, and to examine whether there is a CVF level associated with a low metabolic risk. CVF was estimated by a maximal ergometer bike test on 873 randomly selected children from Sweden and Estonia. Additional measured outcomes included fasting insulin, glucose, triglycerides, HDLC, blood pressure, and the sum of five skinfolds. A metabolic risk score was computed as the mean of the standardized outcomes scores. A risk score <75th percentile was considered to indicate a low metabolic risk. CVF was negatively associated with clustering of metabolic risk factors in children. Receiver operating characteristic curve analysis showed a significant discriminatory accuracy of CVF in identifying the low/high metabolic risk in girls and boys (p < 0.001). The CVF level for a low metabolic risk was 37.0 and 42.1 mL/kg/min in girls and boys, respectively. These levels are similar to the health-related threshold values of CVF suggested by worldwide recognized organizations. In conclusion, the results suggest a hypothetical CVF level for having a low metabolic risk, which should be further tested in longitudinal and/or intervention studies. Abbreviations: AUC, area under the curve CVF, cardiovascular fitness ROC, receiver operating characteristic
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| 5. |
- Ruiz, Jonatan R., et al.
(författare)
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Relations of total physical activity and intensity to fitness and fatness in children : the European Youth Heart Study
- 2006
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 84:2, s. 299-303
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is unclear how the amount and intensity of physical activity (PA) are associated with cardiovascular fitness (CVF) and body fatness in children.Objective: We aimed to examine the associations of total PA and intensity levels to CVF and fatness in children.Design: A cross-sectional study of 780 children aged 9–10 y from Sweden and Estonia was conducted. PA was measured by accelerometry and was expressed as min/d of total PA, moderate PA, and vigorous PA. CVF was measured with a maximal ergometer bike test and was expressed as W/kg. Body fat was derived from the sum of 5 skinfold-thickness measurements. Multiple regression analysis was used to determine the degree to which variance in CVF and body fat was explained by PA, after control for age, sex, and study location.Results: Lower body fat was significantly associated with higher levels of vigorous PA, but not with moderate or total PA. Those children who engaged in >40 min vigorous PA/d had lower body fat than did those who engaged in 10–18 min vigorous PA/d. Total PA, moderate PA, and vigorous PA were positively associated with CVF. Those children who engaged in >40 min vigorous PA/d had higher CVF than did those who accumulated <18 min vigorous PA/d.Conclusions: The results suggest that PA of vigorous intensity may have a greater effect on preventing obesity in children than does PA of lower intensity, whereas both total and at least moderate to vigorous PA may improve children's CVF.
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