title: 5 Hz Repetitive Transcranial Magnetic Stimulation with Maximum Voluntary Muscle Contraction Facilitates Cerebral Cortex Excitability of Normal Subjects.
abstract: BACKGROUND
  Recently, high-frequency repetitive transcranial magnetic stimulation (rTMS) is reported to evaluating the corticospinal pathway and improving both cortical excitability and motor function significantly in subjects. According to some previous reports, the maximum voluntary muscle contraction (MVC) of target muscle can reinforce the influence by rTMS. The aim of this study was to confirm 5 Hz rTMS with MVC in healthy individuals is an effective method to facilitate motor neuron excitability and the efficiency can last at least 30 min post stimulation.
  
  
  OBJECTIVE
  To compare the motor evoked potentials (MEPs) elicited by 5Hz rTMS and 5Hz rTMS combined with MVC.
  
  
  METHODS
  In this randomized, controlled, assessor-blinded, crossover trial, 40 healthy right-handed subjects were divided into group A (n=20) and group B (n=20). All subjects received rTMS over the primary motor cortex area (M1) in the left hemisphere. The parameters of rTMS were 5 Hz, 90.of the resting motor threshold (RMT), for a total of 500 pulses in 100 trains (1-sec inter-stimulus and 8- sec inter-interval). Method 1: All subjects received rTMS over the hand area of left M1. Method 2: All subjects received rTMS at the same stimulated point, combined with maximum voluntary hand griping in each 10 trains. Test 1: group A underwent method 1, while group B underwent method 2. Test 2: A week later, group B underwent method 1, while group A underwent method 2. In each test, the MEP amplitude and latency was measured before (P-rTMS), 5 min after (Post 1) and 30 min after (Post 2) the rTMS intervention.
  
  
  RESULTS
  MEP amplitude increased significantly from baseline at 5 minutes post intervention under both treatment regimes. However for both sequences, it decreased towards baseline under the rTMS intervention at 30 minutes post intervention but remained relatively high when rTMS was combined with MVC. MEP latency decreased significantly from baseline at 5 minutes post intervention under both treatment regimes. For both sequences, it then increased again towards baseline under both treatment regimes at 30 minutes post intervention. Although there was a trend for a less pronounced increase under the combined treatment, this effect was not significant.
  
  
  CONCLUSIONS
  Both 5 Hz rTMS and 5 Hz rTMS combined with MVC facilitate motor cortical excitability, but the enhancement in rTMS with MVC is more pronounced and maintained longer than simple rTMS.
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Yin
authors.forename: Ying
authors.initials: Y
authors.lastname: Shen
authors.forename: Jan Dietrich
authors.initials: JD
authors.lastname: Reinhardt
authors.forename: Chiun-Fan
authors.initials: CF
authors.lastname: Chen
authors.forename: Xueyong
authors.initials: X
authors.lastname: Jiang
authors.forename: Wenjun
authors.initials: W
authors.lastname: Dai
authors.forename: Wenting
authors.initials: W
authors.lastname: Zhang
authors.forename: Sergio
authors.initials: S
authors.lastname: Machado
authors.forename: Oscar
authors.initials: O
authors.lastname: Arias-Carrion
authors.forename: Ti-Fei
authors.initials: TF
authors.lastname: Yuan
authors.affiliation: Department of Rehabilitation Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China. shanclhappy@163.com.
authors.forename: Chunlei
authors.initials: C
authors.lastname: Shan
mesh_terms: D018592:Cross-Over Studies; D004576:Electromyography; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D016037:Single-Blind Method; D013995:Time; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D034941:Upper Extremity / Q000502:physiology*; D014836:Volition / Q000502:physiology; D055815:Young Adult