Effects Of Unilateral Vibration On Contralateral Forearm Muscle Activity
Condition: Osteoporosis; Excitability
MeSH terms: Osteoporosis
Study type: Interventional

Summary: 
      This study hypothesize that radius subjecting to mechanical loading may affect excitability
      of alpha motor neuron innervating muscle, based on its bone mineral density or bone mineral
      content.

      A total of 80 voluntaries are planned to include in this study. Vibration will be applied the
      right forearm. Muscle electrical activity will be measured on ipsilateral and contralateral
      flexor carpi radialis (FCR) muscle at rest as EMGrms by surface electromyography (EMG). The
      rest-EMGrms will be measured at before and during vibration. An increase in muscle electrical
      activity at rest indicates an increase in motor neuron pool activation. The right distal
      radius bone mineral content (BMC) and density will be measured by dual energy X-ray
      absorptiometry (DXA).

      The right radius bone mineral density (BMD) and BMC will be evaluated by bone densitometer
      (GE-LUNAR DPX PRO).

      Motor unit potentials will be measured by electromyography at left flexor carpi radialis.
      Neurotrac ETS device will be used.
    

Detailed description: 
      A functional cooperation exists between bones and skeletal muscles. Bones work together with
      muscles as a simple mechanical lever system to produce body movement. One of the important
      functions of bones is to exert resistance against gravity in order to carry the body. In
      order to carry out their mechanical functions, bones need to have considerable resistance to
      deformation under load. It is well-known that muscle activity (i.e., exercises) improves the
      resistance of bone to mechanical loading, and that it is also important for treating and
      preventing osteoporosis. Resistance and impact training have been shown to induce bone
      formation and/or prevent bone resorption. Skeletal muscles have positive effects on bone
      structure and function. Can bones have an effect on muscle activity? There is only one study
      about the effect of bones on muscles. In this study, it was shown that bones may affect
      muscle strength gain in healthy young adult males.

      Vibration has a strong osteogenic effect. Vibration-induced bone formation is neuronally
      regulated. Vibration can also effectively enhance muscle strength and power. Previous studies
      have shown that vibration increases muscle electromyographic (EMG) activity. But, it has not
      been reported whether bone has an effect on the increase in muscle EMG activity caused by
      vibration or not. The aim of this study was to determine whether radius bone exposed to
      cyclic mechanical loading affects muscle electrical activity of contralateral untrained m.
      flexor carpi radialis in healthy adult volunteers.
    

Intervention name(s): Forearm vibration
Intervention type(s): Procedure
Intervention description(s): Mechanical loading with forearm vibration will be applied right radius in all groups
Other intervention name(s): Cyclic mechanical loading
Intervention model: Single Group Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: bone; motor neuron excitability; forearm vibration; mechanical loading; muscle electrical activity