Oral conjugated linoleic acid supplementation enhanced glycogen resynthesis in exercised human skeletal muscle

J Sports Sci. 2015;33(9):915-23. doi: 10.1080/02640414.2014.970219. Epub 2014 Nov 11.

Abstract

Present study examined the effects of conjugated linoleic acid (CLA) supplementation on glycogen resynthesis in exercised human skeletal muscle. Twelve male participants completed a cross-over trial with CLA (3.8 g/day for 8 week) or placebo supplements by separation of 8 weeks. CLA is a mixture of trans-10 cis-12 and cis-9 trans-11 isomers (50:50). On experiment day, all participants performed 60-min cycling exercise at 75% VO2 max, then consumed a carbohydrate meal immediately after exercise and recovered for 3 h. Biopsied muscle samples from vastus lateralis were obtained immediately (0 h) and 3 h following exercise. Simultaneously, blood and gaseous samples were collected for every 30 min during 3-h recovery. Results showed significantly increased muscle glycogen content with CLA after a single bout of exercise (P < 0.05). Muscle glucose transporter type 4 expression was significantly elevated immediately after exercise, and this elevation was continued until 3 h after exercise in CLA trial. However, P-Akt/Akt ratio was not significantly altered, while glucose tolerance was impaired with CLA. Gaseous exchange data showed no beneficial effect of CLA on fat oxidation, instead lower non-esterified fatty acid and glycerol levels were found at 0 h. Our findings conclude that CLA supplementation can enhance the glycogen resynthesis rate in exercised human skeletal muscle.

Keywords: ergogenic aid; exhaustive exercise; fat oxidation; glycogen content.

Publication types

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

MeSH terms

  • Blood Glucose / metabolism
  • Cross-Over Studies
  • Dietary Supplements*
  • Exercise / physiology*
  • Fatty Acids, Nonesterified / metabolism
  • Glucose Transport Proteins, Facilitative / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Glycogen / biosynthesis*
  • Homeostasis
  • Humans
  • Insulin / blood
  • Linoleic Acids, Conjugated / administration & dosage*
  • Male
  • Muscle, Skeletal / metabolism*
  • Protein-Serine-Threonine Kinases / metabolism
  • Pulmonary Ventilation
  • Young Adult

Substances

  • Blood Glucose
  • Fatty Acids, Nonesterified
  • Glucose Transport Proteins, Facilitative
  • Glucose Transporter Type 4
  • Insulin
  • Linoleic Acids, Conjugated
  • cis-9, trans-11-conjugated linoleic acid
  • trans-10,cis-12-conjugated linoleic acid
  • Glycogen
  • Protein-Serine-Threonine Kinases