6533b855fe1ef96bd12b00a6
RESEARCH PRODUCT
The relative contribution to the plantar-flexor torque of the soleus motor units activated by the H reflex and M response in humans.
Jacques Van HoeckeMarco SchieppatiMarco SchieppatiAlain MartinNicola A. Maffiulettisubject
AdultMaleAction PotentialsPlantar flexionH-ReflexNuclear magnetic resonanceTorqueHumansTibial nerveMuscle SkeletalSoleus musclePhysicsElectromyographyGeneral NeuroscienceAnatomyM responsemusculoskeletal systemElectric StimulationMotor unitAmplitudeMuscle Fibers Slow-TwitchTorqueMuscle Fibers Fast-TwitchH-reflexTibial NerveMuscle Contractiondescription
Abstract This study proposes a method of quantifying the relative contribution to the plantar-flexor torque of soleus H and M responses evoked by tibial nerve stimulation. For ten subjects, the amplitude of the twitch produced by the H wave was plotted against the corresponding potential, for stimuli producing H without M (i.e. in the ascending portion of the H-recruitment curve). It was then assumed that the contribution of H to twitches produced by M plus H was similar for similar H waves on the curve-descending portion. Hence, the contribution of M was estimated, for the range of M waves including those accompanying H max . The estimated mechanical contributions of H and M wave increase linearly with their potentials, the slope of the relationship being greater for H than M. The interpretation of this finding is discussed. A simple formula for assessing the contribution of the H wave to the twitch torque is given.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-07-01 | Neuroscience letters |