title: Effect of resistance training on resting metabolic rate and its estimation by a dual-energy X-ray absorptiometry metabolic map.
abstract: OBJECTIVE
  Fat-free mass (FFM) is the major predictor of resting metabolic rate (RMR). As protein supplementation during resistance training may augment gains in FFM, we investigated the effects of resistance training combined with protein supplementation on RMR and whether RMR responses could be estimated by a dual-energy X-ray absorptiometry (DXA) metabolic map.
  
  
  METHODS
  Healthy adults completed a whole-body periodized resistance training program consisting of 96 workouts (~9 months). Participants were randomly assigned to supplement with whey protein (whey; n=18), soy protein (soy; n=21) or carbohydrate (carb; n=22). RMR was measured using indirect calorimetry (RMR(IC)) and estimated by DXA metabolic mapping (RMR(MM)) pretraining and posttraining.
  
  
  RESULTS
  RMR(IC) increased from pretraining to posttraining in the whole cohort (1653±302 to 1726±291 kcal/day, P=0.001) without differences between the groups. Delta RMR(IC) and RMR(MM) (73±158 vs 52±41 kcal/day were not significantly different by t-test (P=0.303), although they were not significantly correlated (r=0.081; P=0.535). Stepwise regression identified 43% of the shared variance in delta RMR(IC) using total serum thyroxine, RMR(IC) and FFM at baseline (P=0.009).
  
  
  CONCLUSIONS
  These results indicate that 9 months of resistance training significantly increased RMR ~5% on average, but there was wide variability between individuals, which can be partially accounted for by changes in FFM and thyroid hormones.
authors.affiliation: 1] The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA [2] Grupo de Investigación en Fisiología y Bioquimica (PHYSIS), Universidad de Antioquia, Medellín, Colombia.
authors.forename: J C
authors.initials: JC
authors.lastname: Aristizabal
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Freidenreich
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
authors.forename: B M
authors.initials: BM
authors.lastname: Volk
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
authors.forename: B R
authors.initials: BR
authors.lastname: Kupchak
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
authors.forename: C
authors.initials: C
authors.lastname: Saenz
authors.affiliation: Department of Human Sciences, The Ohio State University, Columbus, OH, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Maresh
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Kraemer
authors.affiliation: Department of Human Sciences, The Ohio State University, Columbus, OH, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Volek
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D001481:Basal Metabolism; D002153:Calorimetry, Indirect; D015331:Cohort Studies; D004044:Dietary Proteins / Q000008:administration & dosage*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D010349:Patient Compliance; D015203:Reproducibility of Results; D055070:Resistance Training; D030262:Soybean Proteins / Q000008:administration & dosage; D064133:Sports Nutritional Physiological Phenomena; D000067816:Whey Proteins / Q000008:administration & dosage; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: D004044:Dietary Proteins; D030262:Soybean Proteins; D000067816:Whey Proteins