title: Determination of the maximal fat oxidation point in obese children and adolescents: validity of methods to assess maximal aerobic power.
abstract: We aimed to examine the interchangeability of techniques used to assess maximal oxygen consumption (VO2max) and maximal aerobic power (MAP) employed to express the maximal fat oxidation point in obese children and adolescents. Rate of fat oxidation were measured in 24 obese subjects (13.0 +/- 2.4 years; Body Mass Index 30.2 +/- 6.3 kg m(-2)) who performed a five 4-min stages submaximal incremental cycling exercise. A second cycling exercise was performed to measure VO2max. Results are those of the 20 children who achieved the criterion of RER (>1.02) to assess the attainment of VO2max. Although correlations between results obtained by different methods were strong, Bland-Altman plots showed little agreement between the maximal fat oxidation point expressed as a percentage of measured VO2max and as % VO2max estimated according to ACSM guidelines (underestimation : -5.9%) or using the predictive equations of Wasserman (-13.9%). Despite a mean underestimation of 1.4% several values were out of the limits of agreement when comparing measured MAP and Theoretical MAP. Estimations of VO2max lead to underestimations of the maximal fat oxidation point.
authors.affiliation: Laboratoire Inter-Universitaire de Biologie des Activités Physiques et Sportives, Université Blaise Pascal, Clermont-Ferrand, France. Julien.AUCOUTURIER@univ-bpclermont.fr
authors.forename: Julien
authors.initials: J
authors.lastname: Aucouturier
authors.forename: Mélanie
authors.initials: M
authors.lastname: Rance
authors.forename: Martine
authors.initials: M
authors.lastname: Meyer
authors.forename: Laurie
authors.initials: L
authors.lastname: Isacco
authors.forename: David
authors.initials: D
authors.lastname: Thivel
authors.forename: Nicole
authors.initials: N
authors.lastname: Fellmann
authors.forename: Martine
authors.initials: M
authors.lastname: Duclos
authors.forename: Pascale
authors.initials: P
authors.lastname: Duché
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D002648:Child; D016552:Ergometry / Q000379:methods*; D015444:Exercise; D005080:Exercise Test; D005260:Female; D017408:Guidelines as Topic / Q000592:standards; D006801:Humans; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010807:Physical Endurance; D005082:Physical Exertion; D012955:Societies, Medical