title: Specific neck training induces sustained corticomotor hyperexcitability as assessed by motor evoked potentials.
abstract: METHODS
  Experimental investigation of short-term and long-term corticomotor effects of specific neck training, coordination training, and no training.
  
  
  OBJECTIVE
  To determine the effects of different training programs on the motor neurons controlling the neck muscles as well as the effects of training on muscle strength and muscle fatigue, and the correlations between corticomotor control and motor learning.
  
  
  BACKGROUND
  Training is usually recommended for unspecific neck pain and consists of neck and upper body coordination, strengthening, and endurance exercises. However, it is unclear which type of training is the most effective. No studies have previously investigated the neural effect of neck training and the possible differential effect of specific versus coordination training on corticomotor control.
  
  
  METHODS
  Transcranial magnetic stimulation and electromyography were used to elicit and monitor motor evoked potentials (MEPs) from the trapezius and thumb muscles before and 30 minutes, 1 hour, and 7 days after training. Parameters measured were MEP amplitude, MEP latency, strength, learning effects, and muscle fatigue.
  
  
  RESULTS
  Only specific neck training yielded a 67% increase in MEP amplitudes for up to 7 days after training compared with baseline (P < 0.001). No significant changes were seen after coordination training, no training, and in the within-subject control muscle. The mean muscle strength increased immediately after specific neck training from 56.6 to 61 kg (P < 0.001). No subjective or objective measures of fatigue were observed.
  
  
  CONCLUSIONS
  Specific neck training induced a sustained hyperexcitability of motor neurons controlling the neck muscles compared with coordination training and controls. These findings may prove valuable in the process of developing more effective clinical training programs for unspecific neck pain.
authors.affiliation: Danish Pain Research Center, Aarhus University Hospital, Aarhus, Denmark. brr@ki.au.dk
authors.forename: Bjarne
authors.initials: B
authors.lastname: Rittig-Rasmussen
authors.forename: Helge
authors.initials: H
authors.lastname: Kasch
authors.forename: Anders
authors.initials: A
authors.lastname: Fuglsang-Frederiksen
authors.forename: Troels S
authors.initials: TS
authors.lastname: Jensen
authors.forename: Peter
authors.initials: P
authors.lastname: Svensson
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004576:Electromyography / Q000379:methods; D019054:Evoked Potentials, Motor / Q000502:physiology*; D006801:Humans; D009044:Motor Cortex / Q000502:physiology*; D018763:Muscle Fatigue / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology*; D009334:Neck Muscles / Q000502:physiology*; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult