title: Exogenous CHO oxidation with glucose plus fructose intake during exercise.
abstract: OBJECTIVE
  The purpose of the present study was to determine whether combined ingestion of moderate amounts of glucose plus fructose would result in higher rates of exogenous CHO oxidation compared with an isocaloric amount of glucose alone.
  
  
  METHODS
  Seven endurance-trained male cyclists performed three experimental trials consisting of 150 min of cycling at 65% VO(2max). Subjects ingested a CHO solution providing glucose (GLU) at an average rate of 0.8 g min(-1), glucose (0.54 g min(-1)) plus fructose (0.26 g min(-1)) (GLU + FRU), or plain water (WAT) during exercise. To quantify exogenous CHO oxidation, we prepared CHO solutions using corn-derived GLU and FRU, with a high natural abundance of 13C.
  
  
  RESULTS
  Peak exogenous CHO oxidation rates were not significantly different between GLU and GLU + FRU (0.60 +/- 0.06 and 0.57 +/- 0.06 g min(-1), respectively). Furthermore, average exogenous CHO oxidation rates during the final 90 min of exercise were not significantly different between GLU and GLU + FRU (0.58 +/- 0.05 and 0.56 +/- 0.06 g min(-1), respectively).
  
  
  CONCLUSIONS
  The present study demonstrates that ingesting moderate amounts of glucose plus fructose does not increase exogenous CHO oxidation above that of an isocaloric amount of glucose alone.
authors.affiliation: School of Sport and Exercise Sciences, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Hulston
authors.forename: Gareth A
authors.initials: GA
authors.lastname: Wallis
authors.forename: Asker E
authors.initials: AE
authors.lastname: Jeukendrup
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D016022:Case-Control Studies; D005080:Exercise Test; D005632:Fructose / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008297:Male; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D055815:Young Adult
chemical_list: D005632:Fructose; D005947:Glucose