The addition of fenugreek extract (Trigonella foenum-graecum) to glucose feeding increases muscle glycogen resynthesis after exercise

Amino Acids. 2005 Feb;28(1):71-6. doi: 10.1007/s00726-004-0143-z. Epub 2004 Dec 2.


The purpose of this study was to determine the effects of ingesting an oral supplement containing 4-Hydroxyisoleucine (4-OH-Ile, isolated from fenugreek seeds [Trigonella foenum-graecum]) with a glucose beverage on rates of post-exercise muscle glycogen resynthesis in trained male cyclists. Following an overnight fast (12 hr), subjects completed a 90-minute glycogen depletion ride after which a muscle biopsy was obtained from the vastus lateralis. Immediately and 2 hours after the muscle biopsy, subjects ingested either an oral dose of dextrose (Glu) (1.8 BW(-1)) or 4-OH-Ile supplement (Glu+4-OH-Ile, including 2.0 4-OH-Ile with the same oral dose of dextrose) with a second muscle biopsy 4 hours after exercise. Post exercise muscle glycogen concentration was similar for both trials. Overall, there was a significant increase in glucose and insulin concentrations from time 0 throughout the majority of the 4-hour recovery period, with no significant differences between the two trials at any time point. Although muscle glycogen concentration significantly increased from immediately post exercise to 4 hr of recovery for both trials, the net rate of muscle glycogen resynthesis was 63% greater during Glu+4-OH-Ile (10.6+/-3.3 vs. 6.5+/-2.6 wet wt.(-1).hr.(-1) for the Glu+4-OH-Ile and Glu trials, respectively). These data demonstrate that when the fenugreek extract supplement (4-OH-Ile) is added to a high oral dose of dextrose, rates of post-exercise glycogen resynthesis are enhanced above dextrose alone.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bicycling
  • Blood Glucose / analysis
  • Dietary Supplements
  • Exercise*
  • Glucose / pharmacology*
  • Glycogen / metabolism*
  • Humans
  • Insulin / blood
  • Isoleucine / analogs & derivatives
  • Isoleucine / pharmacology
  • Male
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism*
  • Plant Extracts / pharmacology*
  • Trigonella / chemistry*


  • 4-hydroxyisoleucine
  • Blood Glucose
  • Insulin
  • Plant Extracts
  • Isoleucine
  • Glycogen
  • Glucose