title: Twin-sibling study and meta-analysis on the heritability of maximal oxygen consumption.
abstract: Large individual differences exist in aerobic fitness in childhood and adolescence, but the relative contribution of genetic factors to this variation remains to be established. In a sample of adolescent twins and siblings (n = 479), heart rate (HR) and maximal oxygen uptake (V̇o2max) were recorded during the climax of a graded maximal exercise test. In addition, V̇o2max was predicted in two graded submaximal exercise tests on the cycle ergometer and the treadmill, using extrapolation of the HR/V̇o2 curve to the predicted HRmax. Heritability estimates for measured V̇o2max were 60% in ml/min and 55% for V̇o2max in ml·min(-1)·kg(-1). Phenotypic correlations between measured V̇o2max and predicted V̇o2max from either submaximal treadmill or cycle ergometer tests were modest (0.57 < r < 0.70), in part because of the poor agreement between predicted and actual HRmax. The majority of this correlation was explained by genetic factors; therefore, the submaximal exercise tests still led to very comparable estimates of heritability of V̇o2max. To arrive at a robust estimate for the heritability of V̇o2max in children to young adults, a sample size weighted meta-analysis was performed on all extant twin and sibling studies in this age range. Eight studies, including the current study, were meta-analyzed and resulted in a weighted heritability estimate of 59% (ml/min) and 72% (ml·min(-1)·kg(-1)) for V̇o2max. Taken together, the twin-sibling study and meta-analyses showed that from childhood to early adulthood genetic factors determine more than half of the individual differences in V̇o2max.
authors.affiliation: Department of Biological Psychology, Netherlands Twin Register, VU University, Amsterdam, The Netherlands; EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; and n.m.schutte@vu.nl.
authors.forename: Nienke M
authors.initials: NM
authors.lastname: Schutte
authors.affiliation: Department of Biological Psychology, Netherlands Twin Register, VU University, Amsterdam, The Netherlands; EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; and.
authors.forename: Ineke
authors.initials: I
authors.lastname: Nederend
authors.affiliation: Department of Psychiatry, Medicine, and Pediatrics, Vermont Center for Children, Youth and Families, University of Vermont, College of Medicine, Burlington, Vermont.
authors.forename: James J
authors.initials: JJ
authors.lastname: Hudziak
authors.affiliation: Department of Biological Psychology, Netherlands Twin Register, VU University, Amsterdam, The Netherlands; EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; and.
authors.forename: Meike
authors.initials: M
authors.lastname: Bartels
authors.affiliation: Department of Biological Psychology, Netherlands Twin Register, VU University, Amsterdam, The Netherlands; EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; and.
authors.forename: Eco J C
authors.initials: EJ
authors.lastname: de Geus
mesh_terms: D000293:Adolescent; D000328:Adult; D002245:Carbon Dioxide / Q000378:metabolism; D002648:Child; D005190:Family; D006801:Humans; D040582:Inheritance Patterns / Q000235:genetics*; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption / Q000235:genetics*; D035781:Siblings; D055815:Young Adult
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen
keywords: V̇o2max; adolescents; genetics; maximal exercise test