eCite Digital Repository

Reproducibility of Fatmax and fat oxidation rates during exercise in recreationally trained males


Croci, I and Borrani, F and Byrne, NM and Wood, RE and Hickman, IJ and Cheneviere, X and Malatesta, D, Reproducibility of Fatmax and fat oxidation rates during exercise in recreationally trained males, PloS one, 9, (6) Article e97930. ISSN 1932-6203 (2014) [Refereed Article]


Copyright Statement

Copyright 2014 Croci et al. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

DOI: doi:10.1371/journal.pone.0097930


Aerobic exercise training performed at the intensity eliciting maximal fat oxidation (Fatmax) has been shown to improve the metabolic profile of obese patients. However, limited information is available on the reproducibility of Fatmax and related physiological measures. The aim of this study was to assess the intra-individual variability of: a) Fatmax) measurements determined using three different data analysis approaches and b) fat and carbohydrate oxidation rates at rest and at each stage of an individualized graded test. Fifteen healthy males [body mass index 23.1 0.6 kg/m(2), maximal oxygen consumption (VO2max) 52.0 2.0 ml/kg/min] completed a maximal test and two identical submaximal incremental tests on ergocycle (30-min rest followed by 5-min stages with increments of 7.5% of the maximal power output). Fat and carbohydrate oxidation rates were determined using indirect calorimetry. Fatmax was determined with three approaches: the sine model (SIN), measured values (MV) and 3rd polynomial curve (P3). Intra-individual coefficients of variation (CVs) and limits of agreement were calculated. CV for Fatmax determined with SIN was 16.4% and tended to be lower than with P3 and MV (18.6% and 20.8%, respectively). Limits of agreement for Fatmax were -2 27% of VO2max with SIN, -4 32 with P3 and -4 28 with MV. CVs of oxygen uptake, carbon dioxide production and respiratory exchange rate were <10% at rest and <5% during exercise. Conversely, CVs of fat oxidation rates (20% at rest and 24-49% during exercise) and carbohydrate oxidation rates (33.5% at rest, 8.5-12.9% during exercise) were higher. The intra-individual variability of Fat(max) and fat oxidation rates was high (CV>15%), regardless of the data analysis approach employed. Further research on the determinants of the variability of Fatmax and fat oxidation rates is required.

Item Details

Item Type:Refereed Article
Research Division:Health Sciences
Research Group:Sports science and exercise
Research Field:Exercise physiology
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the health sciences
UTAS Author:Byrne, NM (Professor Nuala Byrne)
ID Code:115732
Year Published:2014
Web of Science® Times Cited:40
Deposited By:Health Sciences
Deposited On:2017-04-06
Last Modified:2017-10-31
Downloads:150 View Download Statistics

Repository Staff Only: item control page