Related Experiment Video
Updated: Jul 6, 2026
05:39
A Fine Motor Task to Study Joint Kinematics in a Preclinical Model of Neurodegenerative Disease
Published on: June 13, 2025
Changes in muscle and joint coordination in learning to direct forces.
Christopher J Hasson1, Graham E Caldwell, Richard E A van Emmerik
1Biomechanics and Motor Control Laboratories, Department of Kinesiology, University of Massachusetts Amherst, 110 Totman Building, 30 Eastman Lane, Amherst, MA 01003-9258, United States. cjhasson@kin.umass.edu
Human Movement Science
|April 15, 2008
Summary
Humans learn to control pedal forces by coordinating muscles and joint torques. Practice improved force direction, showing adaptation in mono- and bi-articular muscle coordination for this dynamic task.
Area of Science:
- Biomechanics
- Motor Control
- Human Physiology
Background:
- Bi-articular muscles are hypothesized to direct external forces.
- The learning process for coordinating mono- and bi-articular muscles in force-directing tasks remains unclear.
Purpose of the Study:
- To investigate how humans learn to coordinate mono- and bi-articular muscles for force-directing tasks.
- To examine changes in joint torques and muscle coordination during a one-legged cycling task with practice.
Main Methods:
- Participants performed a one-legged cycling task, aiming to direct pedal forces perpendicularly to the crank arm.
- Kinematic and kinetic data were analyzed to assess changes in joint motion, torques, and muscle activity patterns after practice.
Main Results:
- Performance in directing pedal forces improved significantly after one practice session.
- Improved force direction correlated with reduced ankle motion and altered knee and hip motion.
- Joint torque patterns shifted, with decreased ankle plantarflexor torque and increased knee/hip flexor torques.
- Both mono- and bi-articular muscle activity patterns changed, with mono-articular muscles showing greater alterations and contributing to work and force direction.
- A decreased coupling between bi-articular muscle activation and joint torque regulation was observed with practice.
Conclusions:
- Humans can learn complex force-directing tasks through practice.
- Learning involves reorganizing joint torque patterns and coordinating mono- and bi-articular muscles.
- Mono-articular muscles play a role in both mechanical work and force direction during this task.
Related Concept Videos
01:24Muscle Coordination and Action
Muscle coordination is a complex and finely tuned process essential for smooth and purposeful movements like flexion, extension, adduction, abduction, and rotation. The human body orchestrates the actions of various muscles working in concert, each with a specific role. Four functional types describe how muscles work together: agonist, antagonist, synergist, and fixator.
Agonists
Agonist muscles, often called prime movers, are the primary muscles responsible for producing a specific movement.
Agonists
Agonist muscles, often called prime movers, are the primary muscles responsible for producing a specific movement.
01:30Three-Dimensional Force System:Problem Solving
A three-dimensional force system refers to a scenario in which three forces act simultaneously in three different directions. This type of problem is commonly encountered in physics and engineering, where it is necessary to calculate the resultant force on the system, which can then be used to predict or analyze the behavior of the object or structure under consideration.
To solve a three-dimensional force system, first resolve each force into its respective scalar components. Do this using...
To solve a three-dimensional force system, first resolve each force into its respective scalar components. Do this using...
01:12Alterations in Muscle Tone ll
Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...
01:29Two-Dimensional Force System: Problem Solving
Solving problems related to two-dimensional force systems is an essential aspect of mechanics and engineering. By applying the principles of vector analysis and force equilibrium, one can determine the effect of multiple forces acting on an object in a two-dimensional space.
The first step to solving a two-dimensional force system problem is to draw a free-body diagram of the object under consideration. This diagram helps identify all the external forces acting on the object, including their...
The first step to solving a two-dimensional force system problem is to draw a free-body diagram of the object under consideration. This diagram helps identify all the external forces acting on the object, including their...
01:18Hierarchy of Motor Control
The hierarchy of motor control refers to the different levels of organization and processing involved in controlling movement in the body. These levels range from higher cortical areas involved in planning and decision-making to lower spinal cord reflexes that respond automatically to external stimuli.
01:20Motor 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...
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...