title: Assessment of the 5-Minute Oxygen Uptake Efficiency Slope in Children With Obesity.
abstract: Poor cardiorespiratory fitness is associated with increased all cause morbidity and mortality. In children with obesity, maximum oxygen uptake (V̇O2max) may not be achieved due to reduced motivation and peripheral fatigue. We aimed to identify a valid submaximal surrogate for V̇O2maxin children with obesity.
  
  
  
  Ninety-two children with obesity (7-16 years) completed a maximal exercise treadmill test and entered a three-month exercise and/or nutrition intervention after which the exercise test was repeated (n = 63). Participants were required to reach V̇O2maxto be included in this analysis (n = 32 at baseline and n = 13 at both time-points). The oxygen uptake efficiency slope (OUES) was determined as the slope of the line when V̇O2(L/min) was plotted against log V̇E. Associations between the maximal OUES, submaximal OUES (at 3, 4, 5 and 6 min of the exercise test) and V̇O2maxwere calculated.
  
  
  
  In the cross-sectional analysis, V̇O2max(L/min) was strongly correlated with 5-min OUES independent of Tanner puberty stage and sex (R2= .80, p < .001). Longitudinal changes in V̇O2maxwere closely reflected by changes in 5-min OUES independent of change in percent body fat (R2= .63, p < .05).
  
  
  
  The 5-min OUES is a viable alternative to V̇O2maxwhen assessing children with obesity.
authors.affiliation: 1 The University of Queensland.
authors.forename: Katrin A
authors.initials: KA
authors.lastname: Dias
authors.affiliation: 1 The University of Queensland.
authors.forename: Concetta E
authors.initials: CE
authors.lastname: Masterson
authors.affiliation: 1 The University of Queensland.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Wallen
authors.affiliation: 2 Norwegian University of Science and Technology.
authors.forename: Arnt E
authors.initials: AE
authors.lastname: Tjonna
authors.affiliation: 2 Norwegian University of Science and Technology.
authors.forename: Mansoureh S
authors.initials: MS
authors.lastname: Hosseini
authors.affiliation: 1 The University of Queensland.
authors.forename: Peter S W
authors.initials: PSW
authors.lastname: Davies
authors.affiliation: 3 The Wesley Hospital.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Cain
authors.affiliation: 1 The University of Queensland.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Leong
authors.affiliation: 4 University of Illinois at Chicago.
authors.forename: Ross
authors.initials: R
authors.lastname: Arena
authors.affiliation: 2 Norwegian University of Science and Technology.
authors.forename: Charlotte B
authors.initials: CB
authors.lastname: Ingul
authors.affiliation: 1 The University of Queensland.
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Coombes
mesh_terms: D000293:Adolescent; D000072599:Cardiorespiratory Fitness; D002648:Child; D003430:Cross-Sectional Studies; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D063766:Pediatric Obesity / Q000503:physiopathology* / Q000628:therapy; D012016:Reference Values
keywords: Exercise intervention; childhood obesity; oxygen consumption