This Article Full Text Full Text (PDF) All Versions of this Article: 90/1/231    most recent Author Manuscript (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Maffeis, C. Articles by Tatò, L. Search for Related Content PubMed PubMed Citation Articles by Maffeis, C. Articles by Tatò, L. Related Collections Obesity

Nutrient Oxidation during Moderately Intense Exercise in Obese Prepubertal Boys

Departments of Pediatrics (C.M., M.Z., M.P., C.B., G.B., E.V., L.T.) and Clinical and Experimental Medicine (M.F.), University of Verona, 37134 Verona, Italy

Address all correspondence and requests for reprints to: Dr. Claudio Maffeis, Department of Pediatrics, University of Verona, Piazzale L. Scuro, 37134 Verona, Italy. E-mail: claudio.maffeis{at}univr.it.

The aim of this study was to measure the nutrient oxidation rate during walking at different speeds and to identify the walking speed associated with the highest fat oxidation rate in a group of prepubertal boys with different levels of adiposity. Twenty-four prepubertal boys (age, 10 ± 1 yr) with different levels of overweight (body mass index, 25.5 ± 3.5 kg/m²; SD score of body mass index, 3.4 ± 1.1) performed a treadmill test. We measured by indirect calorimetry their respiratory exchange while they walked at speeds of 4, 5, and 6 km/h as well as their maximal oxygen uptake. The fat oxidation rate did not change significantly when the speed of walking was increased, whereas carbohydrate oxidation increased significantly (P < 0.001). A significant (P < 0.05) association was found between adiposity (percent fat mass) and the fat to carbohydrate oxidation ratio during walking at 4, 5, and 6 km/h (r = 0.37, r = 0.37, and r = 0.36, respectively), adjusting for exercise intensity (maximal oxygen uptake, percentage). The lowest fat to carbohydrate oxidation ratio, i.e. the highest fat oxidation/carbohydrate oxidation rate, was found at a walking speed of 4 km/h. Moderately intense exercise promoted the highest fat to carbohydrate oxidation ratio. Increasing the exercise intensity did not promote fat oxidation. Therefore, walking at a speed of 4 km/h is recommended as practicable exercise for obese boys and, consequently, for the treatment of childhood obesity.

This article has been cited by other articles:

				U. Ekelund, S. Brage, L. B Sardhina, S. A Anderssen, L. B. Andersen, M. Harro, P. W Franks, A. R Cooper, C. Riddoch, and K. Froberg Reply to C Maffeis Am. J. Clinical Nutrition, June 1, 2005; 81(6): 1449 - 1450. [Full Text] [PDF]