Wrist flexor muscles of elite rowers measured with magnetic resonance spectroscopy

J Appl Physiol (1985). 1989 Sep;67(3):926-32. doi: 10.1152/jappl.1989.67.3.926.


We used phosphorus magnetic resonance spectroscopy to study skeletal muscle metabolism of trained vs. untrained humans. The forearms of highly trained rowers (n = 10) and age-matched controls were placed in a 1.9-T magnet so that the wrist flexor muscles were placed over a 4-cm transmitting and receiving coil. The subjects performed work by depressing a handle attached to an isokinetic ergometer. Relative concentrations of Pi, phosphocreatine (PCr), and ATP were measured along with intracellular pH. Measurements were made at rest, during steady-state and ramp exercise protocols, and during recovery from exercise. At rest the rowers had Pi/PCr that were not different from control. During steady-state exercise rowers (n = 4) had lower Pi/PCr at the same relative power levels, and the slope of the power vs. Pi-PCr curve was significantly greater than for controls. Rowers (n = 4) also had faster rates of PCr recovery after exercise than controls (T1/2 of 24 +/- 2.0 s for rowers and 47 +/- 8.4 s for controls) when power level was adjusted so that all subjects recovered from the same level of Pi/PCr. During a ramp exercise protocol, the initial slope of the power vs. Pi-PCr curve was greater in three of six rowers compared with controls and at the highest power level rowers had lower Pi/PCr values with less drop in pH. At the end of the ramp test, the same degree of muscle fatigue was associated with much lower levels of H2PO-4 (5.7 +/- 0.70 mM) in rowers compared with controls (13.0 +/- 1.8 mM).(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

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

MeSH terms

  • Female
  • Humans
  • Magnetic Resonance Spectroscopy
  • Male
  • Muscles / metabolism*
  • Phosphates / metabolism
  • Phosphocreatine / metabolism
  • Physical Education and Training
  • Physical Endurance
  • Sports*
  • Wrist


  • Phosphates
  • Phosphocreatine