Force training induces changes in human muscle membrane properties.
Human muscle membrane properties can be assessed in vivo by recording muscle velocity recovery cycles (MVRCs). This study was undertaken to study the effect of muscle force training on MVRC parameters.



MVRCs with 1 to 5 conditioning stimuli were recorded from brachioradialis muscle before and after 2 weeks of muscle force training in 12 healthy subjects. The effects of training on relative refractory period and early and late supernormality were quantified.



Force training induced a reduction of relative refractory period (P < 0.0001), while early supernormality was increased (P < 0.02) and peaked earlier (P < 0.01). Late supernormality and the increases in late supernormality due to 2 and 5 conditioning stimuli remained unchanged.



Muscle force training leads to hyperpolarization of the resting muscle membrane potential, probably caused by an increase in the number of sodium pump sites. Muscle Nerve 54: 144-146, 2016.
Department of Neurosurgery, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.|Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.
Werner J
WJ
Z'Graggen
Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.
Joël P
JP
Trautmann
Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom.
Hugh
H
Bostock
D000328:Adult; D055592:Biophysical Phenomena; D004558:Electric Stimulation; D004576:Electromyography; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008564:Membrane Potentials / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012032:Refractory Period, Electrophysiological / Q000502:physiology*; D013663:Teaching; D055815:Young Adult
early supernormality; force training; muscle membrane potential; muscle velocity recovery cycle; relative refractory period