Exercise counteracts the effects of short-term overfeeding and reduced physical activity independent of energy imbalance in healthy young men

J Physiol. 2013 Dec 15;591(24):6231-43. doi: 10.1113/jphysiol.2013.262709. Epub 2013 Oct 28.

Abstract

Physical activity can affect many aspects of metabolism but it is unclear to what extent this relies on manipulation of energy balance. Twenty-six active men age 25 ± 7 years (mean ± SD) were randomly assigned either to consume 50% more energy than normal by over-consuming their habitual diet for 7 days whilst simultaneously restricting their physical activity below 4000 steps day(-1) to induce an energy surplus (SUR group; n = 14) or to the same regimen but with 45 min of daily treadmill running at 70% of maximum oxygen uptake (SUR+EX group; n = 12). Critically, the SUR+EX group received additional dietary energy intake to account for the energy expended by exercise, thus maintaining a matched energy surplus. At baseline and follow-up, fasted blood samples and abdominal subcutaneous adipose tissue biopsies were obtained and oral glucose tolerance tests conducted. Insulinaemic responses to a standard glucose load increased 2-fold from baseline to follow-up in the SUR group (17 ± 16 nmol (120 min) l(-1); P = 0.002) whereas there was no change in the SUR+EX group (1 ± 6 nmol (120 min) l(-1)). Seven of 17 genes within adipose tissue were differentially expressed in the SUR group; expression of SREBP-1c, FAS and GLUT4 was significantly up-regulated and expression of PDK4, IRS2, HSL and visfatin was significantly down-regulated (P ≤ 0.05). The pAMPK/AMPK protein ratio in adipose tissue was significantly down-regulated in the SUR group (P = 0.005). Vigorous-intensity exercise counteracted most of the effects of short-term overfeeding and under-activity at the whole-body level and in adipose tissue, even in the face of a standardised energy surplus.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue / metabolism
  • Adolescent
  • Adult
  • Down-Regulation
  • Energy Intake*
  • Energy Metabolism*
  • Exercise*
  • Fasting / metabolism
  • Glucose Intolerance
  • Glucose Transporter Type 4 / genetics
  • Glucose Transporter Type 4 / metabolism
  • Homeostasis
  • Humans
  • Insulin Receptor Substrate Proteins / genetics
  • Insulin Receptor Substrate Proteins / metabolism
  • Male
  • Nicotinamide Phosphoribosyltransferase / genetics
  • Nicotinamide Phosphoribosyltransferase / metabolism
  • Oxygen Consumption
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Pyruvate Dehydrogenase Acetyl-Transferring Kinase
  • Sterol Esterase / genetics
  • Sterol Esterase / metabolism
  • Sterol Regulatory Element Binding Protein 1 / genetics
  • Sterol Regulatory Element Binding Protein 1 / metabolism
  • fas Receptor / genetics
  • fas Receptor / metabolism

Substances

  • FAS protein, human
  • Glucose Transporter Type 4
  • IRS2 protein, human
  • Insulin Receptor Substrate Proteins
  • PDK4 protein, human
  • Pyruvate Dehydrogenase Acetyl-Transferring Kinase
  • Sterol Regulatory Element Binding Protein 1
  • fas Receptor
  • Nicotinamide Phosphoribosyltransferase
  • Protein Serine-Threonine Kinases
  • Sterol Esterase