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 Concept Videos

Motor Units01:13

Motor Units

The motor unit is a fundamental component of the neuromuscular system and plays a crucial role in coordinating muscle contractions. It consists of a somatic motor neuron, which connects and controls multiple skeletal muscle fibers, forming a single functional segment. The axon of the motor neuron branches out and establishes synaptic connections known as neuromuscular junctions with individual muscle fibers within the motor unit.
Motor units come in different sizes, with smaller units...
Motor Units00:46

Motor Units

A motor unit consists of two main components: a single efferent motor neuron (i.e., a neuron that carries impulses away from the central nervous system) and all of the muscle fibers it innervates. The motor neuron may innervate multiple muscle fibers, which are single cells, but only one motor neuron innervates a single muscle fiber.
Motor Unit Stimulation01:20

Motor Unit Stimulation

When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...
Muscle Stimulation Frequency01:22

Muscle Stimulation Frequency

The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Work and Energy for Variable Forces01:10

Work and Energy for Variable Forces

When an object is acted upon by a variable force, the amount of work done and the change in energy of the object can be more complex to calculate compared to when a constant force is applied. Work is the product of force and displacement, while energy is the capacity of a system to do work. When a constant force is applied to an object, the work done can be calculated as the product of the force and the distance moved in the direction of the force. However, when a variable force is applied, the...
Multicompartment Models: Overview01:14

Multicompartment Models: Overview

Multicompartment models are mathematical constructs that depict how drugs are distributed and eliminated within the body. They segment the body into several compartments, symbolizing various physiological or anatomical areas connected through drug transfer processes such as absorption, metabolism, distribution, and elimination.
These models offer a more comprehensive representation of drug behavior in the body than one-compartment models. They accommodate the complexity of drug distribution,...

You might also read

Related Articles

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

Sort by
Same author

Multisignal Collaborative Detection of Thiram Based on Dual-Functional Iron-Based Metal Organic Frameworks.

Journal of agricultural and food chemistry·2026
Same author

Lanzhou Lily (<i>Lilium davidii var. unicolor</i>) Extract Alleviates Chronic Stress-Induced Mood Disturbances by Suppressing Neuroinflammation and Modulating the Gut-Brain Axis in Mice.

Food science & nutrition·2026
Same author

Machine Learning-Assisted Surface Ligand Engineering Strategy for Enhanced Sensitivity of Immunoassay Platform.

Analytical chemistry·2026
Same author

Controlling thermoreversibility and hole conductivity in thermoresponsive ionic biogels using phase morphology for neurohaptics.

Science advances·2026
Same author

Role of nutritional indices (PNI, CONUT, GNRI) in predicting delirium in hospitalised individuals: A systematic review and meta-analysis.

General hospital psychiatry·2026
Same author

Nucleic acid aptamer-functionalized magnetic MIL-53(Al)-NH<sub>2</sub> for highly selective magnetic dispersion solid-phase extraction of chloramphenicol.

The Analyst·2026

Related Experiment Video

Updated: May 29, 2026

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
13:07

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo

Published on: December 5, 2012

Motor-unit pool model of continuous and discrete force variability.

Xiaogang Hu1, Karl M Newell

  • 1Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA.

Motor Control
|September 24, 2011
PubMed
Summary

This study explored how motor unit properties affect force variability in continuous and discrete muscle contractions. Findings reveal peak firing rate and motoneuron synchrony influence force scaling, offering insights into neuromuscular control.

More Related Videos

Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle
06:54

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle

Published on: December 26, 2020

Related Experiment Videos

Last Updated: May 29, 2026

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
13:07

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo

Published on: December 5, 2012

Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle
06:54

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle

Published on: December 26, 2020

Area of Science:

  • Neuromuscular Physiology
  • Motor Control
  • Computational Neuroscience

Background:

  • Force variability differs between continuous and discrete isometric contractions.
  • Understanding these differences is key to comprehending motor control mechanisms.
  • Existing models require refinement to capture these distinct force scaling properties.

Purpose of the Study:

  • To investigate the neuromuscular mechanisms underlying different force variability scaling functions in continuous versus discrete isometric forces.
  • To simulate muscle forces using a detailed motor unit model and manipulate key physiological parameters.
  • To examine the impact of time-to-peak force on discrete force variability.

Main Methods:

  • Simulated muscle forces using the Fuglevand et al. (1993) model, incorporating motor unit recruitment and rate coding.
  • Manipulated parameters including peak firing rate, motoneuron synchrony, and recruitment range.
  • Analyzed the relationship between simulated force, force variability, and time-to-peak force.

Main Results:

  • Peak firing rate, motoneuron synchrony, and recruitment range were identified as key contributors to distinct force variability functions.
  • A shorter time-to-peak force correlated with increased peak force variability.
  • The simulation model successfully replicated the observed differences in force variability scaling between continuous and discrete contractions.

Conclusions:

  • The study successfully modeled the distinct force variability scaling functions observed in continuous and discrete isometric contractions.
  • Simulation results provide preliminary evidence for the role of specific neuromuscular mechanisms, such as firing rate and synchrony, in modulating force variability.
  • These findings advance our understanding of the neural control underlying different types of muscle force production.