Cardiorespiratory Fitness in Childhood and Adolescence Affects Future Cardiovascular Risk Factors: A Systematic Review of Longitudinal Studies

Abstract

BackgroundAlthough cardiorespiratory fitness (CRF) in childhood and adolescence may be linked to future cardiovascular health, there is currently limited evidence for a longitudinal association.ObjectivesTo provide a systematic review on the prospective association between CRF in childhood and adolescence and cardiovascular disease (CVD) risk factors at least 2 years later.MethodsUsing a systematic search of Medline, Embase, and SPORTDiscus, relevant articles were identified by the following criteria: generally healthy children and adolescents between 3 and 18 years of age with CRF assessed at baseline, and a follow-up period of ≥ 2 years. The outcome measures were CVD risk factors. We appraised quality of the included articles with STROBE and QUIPS checklists.ResultsAfter screening 7524 titles and abstracts, we included 38 articles, assessing 44,169 children and adolescents followed up for a median of 6 years. Eleven articles were of high quality. There was considerable heterogeneity in methodology, measurement of CRF, and outcomes, which hampered meta-analysis. In approximately half of the included articles higher CRF in childhood and adolescence was associated with lower body mass index (BMI), waist circumference, body fatness and lower prevalence of metabolic syndrome in later life. No associations between CRF in childhood and adolescence and future waist-to-hip ratio, blood pressure, lipid profile, and glucose homeostasis were observed.ConclusionAlthough about half of the included articles reported inverse associations between CRF in childhood and adolescence and future BMI, body fatness, and metabolic syndrome, evidence for other CVD risk factors was unconvincing. Many articles did not account for important confounding factors such as adiposity. Recommendations for future research include standardizing the measurement of CRF, i.e. by reporting VO2max, using standardized outcome assessments, and performing individual patient data meta-analyses.Electronic supplementary materialThe online version of this article (10.1007/s40279-018-0974-5) contains supplementary material, which is available to authorized users.

Estimated cardiorespiratory fitness in childhood and cardiometabolic health in adulthood: 1970 British Cohort Study

“…There was evidence for associations of higher childhood CRF with lower BMI, waist circumference, body fatness, and lower prevalence of metabolic syndrome in later life, but only in around half the studies. No consistent associations between childhood CRF and future waist‐to‐hip ratio, blood pressure, lipid profile, and glucose homeostasis were observed . Thus, the mixed findings are largely consistent with the present results in relation to childhood fitness and adult risk markers.…”

“…Indeed, the consensus is that there are inverse associations between cardiorespiratory fitness and morbidity and mortality . The associations between cardiorespiratory fitness and health in children are less well understood . For example, more research is required to better understand the associations between cardiorespiratory fitness in childhood and cardiometabolic risk factors in adulthood, and if fitness accrued through adulthood can counteract poor fitness in childhood.…”

The influence of cardiorespiratory fitness on clustered cardiovascular disease risk factors and the mediator role of body mass index in youth: The UP&DOWN Study

“…Because mediation analysis assumes that the independent variable causes the mediator, BMI may be an intermediate step in the causal pathway between CRF and CVD risk factors. Previously, CRF has been negatively associated with adiposity in youth, and it is considered a predictor of adiposity in later years . The physiological mechanisms by which CRF affects adiposity may include the effect that aerobic exercise exerts on the expression and activity of carnitine palmitoyl transferase I (an enzyme that controls the fatty acids movement into the mitochondria), as well as the increase in β‐Hydroxy acyl‐CoA dehydrogenase protein expression (a key enzyme that regulates fat oxidation) .…”

“…36 37 , and it is considered a predictor of adiposity in later years. 5,7,38 The physiological mechanisms by which CRF affects adiposity may include the effect that aerobic exercise exerts on the expression and activity of carnitine palmitoyl transferase I (an enzyme that controls the fatty acids movement into the mitochondria), as well as the increase in β-Hydroxy acyl-CoA dehydrogenase protein expression (a key enzyme that regulates fat oxidation). 39 On the other hand, adipose tissue produces several adipokines involved in inflammation.…”

“…For instance, high cardiorespiratory fitness (CRF) levels in childhood and adolescence has been associated with a healthier cardiovascular profile 6 , and it is considered a strong predictor of CVD risk factors later in life. 5,7 Moreover, the cardiovascular health at these ages and in future life is importantly affected by weight status during childhood and adolescence. 8,9 Given that CRF affects weight status, they may lay on the same causal pathway, making it difficult to determine the extent to which each variable affects CVD risk.…”