title: Effect of prior moderate exercise on postprandial metabolism in men with type 2 diabetes: heterogeneity of responses.
abstract: Prior moderate exercise has been shown consistently to reduce postprandial triglyceride (TG) concentrations in non-diabetic adults, but its effects in men with type 2 diabetes are not known. This study aimed to determine the effect of moderate exercise on postprandial metabolism in men with type 2 diabetes. Ten middle-aged men with type 2 diabetes underwent two oral fat tolerance tests (blood taken fasting and for 8 h after a meal containing 80 g fat, 70 g carbohydrate) in random order. On the afternoon before one test, participants performed a 90-min treadmill walk (Exercise); no exercise was performed before the CONTROL test. Exercise significantly reduced fasting glucose (
  
  
  METHODS
  9.08+/-0.75 mmol l(-1), Exercise: 8.40+/-0.72 mmol l(-1), p=0.033) and insulin (
  
  
  METHODS
  8.01+/-0.98 microU ml(-1), Exercise: 6.81+/-0.93 microU ml(-1), p=0.046) and increased fasting 3-hydroxybutyrate (
  
  
  METHODS
  87.1+/-19.2 micromol l(-1), Exercise: 134.3+/-28.4 micromol l(-1), p=0.011); reduced postprandial insulin by 11.0% (p=0.04) and increased postprandial 3-hydroxybutyrate by 31.8% (p=0.03); but did not significantly change fasting or postprandial triglyceride or NEFA concentrations. However, the exercise-induced change in postprandial triglyceride concentration ranged from -32.3 to +28.3% and the exercise-induced change in fasting 3-hydroxybutyrate concentration (a marker of hepatic fatty acid oxidation) was highly correlated with the exercise-induced changes in fasting and postprandial triglyceride (r=0.68, p=0.03 for both). Thus, inter-individual variation in propensity to increase hepatic fatty acid oxidation following exercise may account for the considerable heterogeneity in triglyceride responses to moderate exercise observed in men with type 2 diabetes.
authors.affiliation: Department of Vascular Biochemistry, University of Glasgow, United Kingdom. j.gill@bio.gla.ac.uk
authors.forename: Jason M R
authors.initials: JM
authors.lastname: Gill
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Mamari
authors.forename: William R
authors.initials: WR
authors.lastname: Ferrell
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Cleland
authors.forename: Colin G
authors.initials: CG
authors.lastname: Perry
authors.forename: Naveed
authors.initials: N
authors.lastname: Sattar
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Packard
authors.forename: Muriel J
authors.initials: MJ
authors.lastname: Caslake
authors.forename: John R
authors.initials: JR
authors.lastname: Petrie
mesh_terms: D000328:Adult; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000503:physiopathology*; D004041:Dietary Fats / Q000097:blood / Q000493:pharmacokinetics; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005215:Fasting / Q000502:physiology; D005230:Fatty Acids, Nonesterified / Q000097:blood; D006801:Humans; D007659:Ketones / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology*; D014280:Triglycerides / Q000097:blood
chemical_list: D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007659:Ketones; D014280:Triglycerides