Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Maximum bilateral contractions are modified by neurally mediated interlimb effects.

J D Howard1, R M Enoka

  • 1Department of Exercise and Sport Sciences, University of Arizona, Tucson 85721.

Journal of Applied Physiology (Bethesda, Md. : 1985)
|January 1, 1991
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Contralateral Effects of Unilateral Strength and Skill Training: Modified Delphi Consensus to Establish Key Aspects of Cross-Education.

Sports medicine (Auckland, N.Z.)·2020
Same author

Tutorial: Analysis of motor unit discharge characteristics from high-density surface EMG signals.

Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology·2020
Same author

New method for assessing hand disinfection shows that pre-operative alcohol/chlorhexidine rub is as effective as a traditional surgical scrub.

The Journal of hospital infection·2014
Same author

A 3'-UTR KRAS-variant is associated with cisplatin resistance in patients with recurrent and/or metastatic head and neck squamous cell carcinoma.

Annals of oncology : official journal of the European Society for Medical Oncology·2014
Same author

A unique form of light-load training improves steadiness and performance on some functional tasks in older adults.

Scandinavian journal of medicine & science in sports·2012
Same author

Anaphylaxis and other adverse reactions to blue dyes: a case series.

Anaesthesia and intensive care·2011

The bilateral deficit, where one limb produces less force in a two-limb contraction than alone, is caused by neural mechanisms. This interaction affects homologous muscles and is influenced by training.

Area of Science:

  • Neuromuscular physiology
  • Human motor control
  • Exercise science

Background:

  • A bilateral deficit is observed when force produced by a single limb during a maximal bilateral contraction is less than during a maximal unilateral contraction.
  • The underlying mechanisms contributing to this phenomenon remain incompletely understood, with neural factors being a primary area of investigation.

Purpose of the Study:

  • To investigate whether neural mechanisms are responsible for the bilateral deficit in maximal force production.
  • To explore the influence of training status and inter-limb muscle synergies on bilateral force deficits and facilitation.

Main Methods:

  • Three groups (untrained, cyclists, weight lifters) performed maximal isometric tasks using one or two limbs (legs or arm-leg combination).
  • Electromyogram (EMG) activity was recorded during maximal contractions.

Related Experiment Videos

  • A second experiment involved electrical stimulation of one limb during maximal contraction of the contralateral limb to assess inter-limb neural interactions.

    • Main Results:

    • Untrained subjects showed a bilateral deficit, while cyclists exhibited no deficit, and weight lifters demonstrated bilateral facilitation.
    • The bilateral deficit was specific to homologous contralateral muscles (e.g., left leg and right leg, but not left arm and right leg).
    • Electrical stimulation of the resting limb increased maximal voluntary force in the activated limb, with greater increases observed in subjects who typically show bilateral facilitation.

    Conclusions:

    • Inter-limb interactions during maximal bilateral contractions are significantly mediated by neural mechanisms.
    • Training status influences the presence and magnitude of the bilateral deficit or facilitation.
    • Neural pathways facilitate or inhibit force production in one limb based on the activation status of the contralateral limb.