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

Muscle Stimulation Frequency01:22

Muscle Stimulation Frequency

2.4K
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...
2.4K
Excitation-Contraction Coupling in Skeletal Muscles01:20

Excitation-Contraction Coupling in Skeletal Muscles

8.7K
Excitation-contraction coupling is a series of events that occur between generating an action potential and initiating a muscle contraction. It occurs at the triad, a structure found in skeletal muscle fibers that comprise a T-tubule and terminal cisternae of the sarcoplasmic reticulum on each side. These triads are visible in longitudinally sectioned muscle fibers. They are typically located at the A-I junction — the junction between the A and I bands of the sarcomere.
When an action...
8.7K
Isotonic and Isometric Muscle Contractions01:22

Isotonic and Isometric Muscle Contractions

3.7K
Two primary types of muscle contractions are isotonic and isometric, each serving unique functions and involving distinct mechanisms. Both isotonic and isometric contractions are integral to the body's complex system of movement and stability. Isotonic exercises contribute significantly to functional strength and movement, while isometric contractions are crucial for maintaining posture and joint stability.
Isotonic contractions
Isotonic contractions occur when a muscle changes length while...
3.7K
Relaxation of Skeletal Muscles01:29

Relaxation of Skeletal Muscles

3.4K
The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open....
3.4K
Actin and Myosin in Muscle Contraction01:16

Actin and Myosin in Muscle Contraction

13.9K
Actin and myosin are contractile proteins that form the sarcomere found in skeletal muscle tissues for regulating muscle contraction. Actin, a globular contractile protein, interacts with myosin for muscle contraction. The skeletal tissue appears striped or striated under a microscope due to the repeated arrangement of contractile proteins actin and myosin along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes...
13.9K
Fascicle Arrangement in Skeletal Muscles01:25

Fascicle Arrangement in Skeletal Muscles

2.2K
Fascicles are bundles of muscle fibers in a skeletal muscle. Muscle fascicle arrangement is directly associated with the power and range of motion of various muscles. The configuration of these fascicles can vary, leading to different functional outcomes.
The four primary types of muscle based on fascicle arrangement are:
2.2K

You might also read

Related Articles

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

Sort by
Same author

The cholinergic system is involved in cervical dystonia - An [<sup>18</sup>F]FEOBV PET study.

Neurobiology of disease·2026
Same author

Beyond the surface: A prospective case-control study of electromyography in cervical dystonia.

Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology·2026
Same author

Intermuscular coherence during co-contraction eliciting tasks as a biomarker for dystonia and GPi-DBS efficacy.

Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology·2024
Same author

Connecting the dots - A systematic review on coherence analysis in dystonia.

Neurobiology of disease·2024
Same author

Treatment of task-specific dystonia in sports: A systematic review.

Clinical parkinsonism & related disorders·2024
Same author

Personality in speed skaters with skater's cramp: A preliminary cross-sectional study.

Journal of psychosomatic research·2023

Related Experiment Video

Updated: Aug 16, 2025

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity
08:40

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

Published on: June 12, 2019

7.5K

Inter-muscular coherence in speed skaters with skater's cramp.

B Nijenhuis1, M A J Tijssen2, T van Zutphen3

  • 1Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; Expertise Center Movement Disorders Groningen, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; University of Groningen, Faculty Campus Fryslân, Leeuwarden, the Netherlands.

Parkinsonism & Related Disorders
|December 23, 2022
PubMed
Summary

Skater's cramp, a movement disorder in speed skaters, may stem from central nervous system issues. Higher inter-muscular coherence during skating in affected skaters suggests a task-specific dystonia.

Keywords:
DystoniaInter-muscular coherenceSpeed skating

More Related Videos

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
14:55

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Published on: April 18, 2011

13.9K
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
07:30

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations

Published on: May 1, 2018

15.5K

Related Experiment Videos

Last Updated: Aug 16, 2025

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity
08:40

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

Published on: June 12, 2019

7.5K
Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
14:55

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Published on: April 18, 2011

13.9K
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
07:30

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations

Published on: May 1, 2018

15.5K

Area of Science:

  • Neuroscience
  • Movement Disorders
  • Sports Medicine

Background:

  • Skater's cramp is a debilitating, career-ending movement disorder affecting expert speed skaters, often suspected to be a task-specific dystonia.
  • Task-specific dystonias are frequently associated with central nervous system dysregulation, evidenced by increased inter-muscular coherence.

Purpose of the Study:

  • To investigate whether increased inter-muscular coherence is present in speed skaters with skater's cramp.
  • To explore if elevated inter-muscular coherence serves as an indicator of central dysregulation and supports the diagnosis of task-specific dystonia.

Main Methods:

  • Inter-muscular coherence in the theta-band was measured during a stationary muscle activation task (10%, 20%, 50% maximum voluntary contraction) in 14 affected and 14 control skaters.
  • Wavelet coherence analysis was performed during key moments of the skating stroke cycle.
  • Electromyography (EMG) amplitude was recorded and correlated with coherence.

Main Results:

  • No significant difference in coherence was observed during the stationary task between affected and control skaters.
  • During skating, affected skaters exhibited higher inter-muscular coherence in their impacted leg compared to their non-impacted leg (p=0.05).
  • A subgroup of severely affected skaters (n=6) showed significantly higher coherence in the impacted leg compared to both legs of controls (p<0.02).
  • EMG amplitude correlated with coherence in the impacted leg of affected skaters (p=0.009).

Conclusions:

  • The preliminary finding of higher inter-muscular coherence in severe skater's cramp cases suggests central nervous system dysregulation.
  • These results strengthen the hypothesis that skater's cramp is a task-specific dystonia.