European Journal of Applied Physiology

, Volume 96, Issue 6, pp 722–728

Chronic neural adaptation induced by long-term resistance training in humans

  • Miguel Fernandez del Olmo
  • Pedro Reimunde
  • Oscar Viana
  • Rafael Martin Acero
  • Javier Cudeiro
Original Article

Abstract

While it is known that resistance training causes changes in the central nervous system (CNS) in the initial stages of training, there have been few studies of cumulative or sustained neural adaptation to resistance training beyond the initial periods. To further investigate this we compared the electromyographic (EMG) response to transcranial magnetic stimulation (TMS) during voluntary contractions of ten subjects who have been training for more than 2 years, resistance-training (RT) group, and ten subjects that have never participated in resistance training (NT). The active motor threshold for biceps brachii was obtained during voluntary elbow flexion at 10% of maximal voluntary contraction (MVC). TMS was also delivered at 100% of the maximal stimulator output while the participants exerted forces ranging from 10 to 90% of MVC. Evoked force, motor-evoked potential (MEP) amplitude and latency from biceps brachii was recorded for each condition to explore changes in corticospinal excitability. The evoked force was significantly lower in the RT group in comparison with the NT group between 30 and 70% of MVC intensity (P<0.05). At 90% of MVC, nine subjects from the RT group showed an absence in the evoked force while this occurred in only five subjects from the NT group. The MEP amplitude and latency changed significantly (P<0.001) with increasing levels of contraction, without significant difference between groups. These results indicate that changes in the CNS are sustained in the log-term practices of resistance training and permit a higher voluntary activation at several intensities of the MVC.

Keywords

Transcranial magnetic stimulation Resistance training Neural adaptation Voluntary contraction Submaximal contraction 

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Miguel Fernandez del Olmo
    • 1
    • 2
    • 3
  • Pedro Reimunde
    • 1
  • Oscar Viana
    • 1
  • Rafael Martin Acero
    • 1
  • Javier Cudeiro
    • 1
  1. 1.Department of Medicine-INEF-Galicia, Laboratory of Neuroscience and Motor Control (NEUROcom)Universidad de A CoruñaA CoruñaSpain
  2. 2.Department of MedicineNEUROcomA CoruñaSpain
  3. 3.Sobell DepartmentThe Institute of NeurologyWC1N 3BGUK

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