Adenosine triphosphate production rates, metabolic economy calculations, pH, phosphomonoesters, phosphodiesters, and force output during short-duration maximal isometric plantar flexion exercises and repeated maximal isometric plantar flexion exercises

Muscle Nerve. 1997 Mar;20(3):336-46. doi: 10.1002/(SICI)1097-4598(199703)20:3<336::AID-MUS11>3.0.CO;2-Z.


Measurements of adenosine triphosphate (ATP) production rates, metabolic economy, intracellular pH, phosphodiesters, and phosphomonoesters along with the force output were used to study 90-s maximum voluntary contractions and two new exercise protocols (20-10 and 30-16 exercises). The 20-10 exercise consisted of thirty-one 20-s maximal voluntary contractions separated by 10-s rest periods. The 30-16 exercise consisted of twenty 30-s maximal voluntary contractions separated by 16-s rest periods. There were no differences in ATP production rates, metabolic economy, intracellular pH, or force output between the 20-10 and 30-16 exercises. The 20-10 exercises accumulated more phosphomonoesters than the 30-16 exercises. These increases in phosphomonoesters may be attributed to increased accumulations of glucose-6-phosphate and/or inosine monophosphate. The increased perception of effort reported during and after the 20-10 exercises was not present during the 30-16 or 90-s exercises. This increased perception of effort may be related to increases in lactate, glucose-6-phosphate, inosine monophosphate, and/or NH3.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphate / biosynthesis*
  • Exercise*
  • Female
  • Foot / physiology*
  • Glucose-6-Phosphate / metabolism
  • Humans
  • Hydrogen-Ion Concentration
  • Inosine Monophosphate / metabolism
  • Isometric Contraction*
  • Magnetic Resonance Spectroscopy
  • Male
  • Muscle Fatigue / physiology
  • Muscles / metabolism
  • Organophosphorus Compounds / metabolism*
  • Self Concept
  • Time Factors


  • Organophosphorus Compounds
  • Inosine Monophosphate
  • Glucose-6-Phosphate
  • Adenosine Triphosphate