在行走过程中,首选速度和固定速度之间的脚神经肌肉控制的差异
概括
首选的步行速度优化了脚神经肌肉控制,使用较少的肌肉协同作用和比固定速度更强的神经协调. 这种步态模式可能会提高能量效率和认知功能.
科学领域:
- 生物力学 生物力学
- 神经科学是一个神经科学.
- 人类运动科学科学 人类运动科学
背景情况:
- 偏好的步行速度与节能和认知益处有关.
- 在偏好的步行速度下,底层的神经肌肉控制机制尚未完全理解.
- 调查脚神经肌肉控制偏好和固定步行速度之间的差异至关重要.
研究的目的:
- 为了比较脚神经肌肉控制的首选和各种固定步行速度.
- 在不同的步态条件下分析肌肉协同作用和肌肉间一致性.
- 阐明偏好步行速度的好处的神经肌肉基础.
主要方法:
- 表面电肌图 (EMG) 在18名健康成年人中记录了脚肌肉活动.
- 参与者以首选,首选匹配的控制和固定速度 (1-6公里/小时) 步行.
- 计算了肌肉协同作用和肌肉间的一致性 (8-60 Hz).
主要成果:
- 首选速度显示较少的肌肉协同作用和较高的肌肉间连贯度 (8-42 Hz) 与PMCS相比.
- 缓慢的固定速度涉及更多的肌肉协同作用和较弱的足部曲器合 (26-60 Hz),而不是首选和快速的速度.
- 首选和更快的固定速度表现出类似的对脚肌肉的模块化控制.
结论:
- 喜欢的步行速度显著影响脚神经肌肉控制,可能会影响能量使用和认知负载.
- 步行速度影响肌肉协同组织和肌肉间协调.
- 研究结果表明,偏好的和更快的固定速度具有类似的神经肌肉控制策略,为未来的研究设计提供信息.
相关概念视频
01:48Classification of Skeletal Muscle Fibers
Skeletal muscles continuously produce ATP to provide the energy that enables muscle contractions. Skeletal muscle fibers can be categorized into three types based on differences in their contraction speed and how they produce ATP, as well as physical differences related to these factors. Most human muscles contain all three muscle fiber types, albeit in varying proportions.
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
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...
01:22Muscle 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...
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
01:27Specialized Characteristics of Cardiac Muscles
The primary role of cardiac muscles is to propel blood throughout the cardiovascular system. The cardiac muscle cells, or cardiomyocytes, exhibit specialized characteristics that allow them to perform this function.
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...
01:11Direct Motor Pathways
The direct motor pathways, also known as the pyramidal tracts, are a group of neural pathways that originate in the brain and descend through the spinal cord. They control the voluntary movement of the body. There are two major direct motor pathways: the corticospinal and the corticobulbar tracts.
The corticospinal tract is responsible for the voluntary movement of the limbs and trunk. It originates in the cerebral cortex of the brain and descends through the cerebrum's internal capsule and the...
The corticospinal tract is responsible for the voluntary movement of the limbs and trunk. It originates in the cerebral cortex of the brain and descends through the cerebrum's internal capsule and the...
01:31Regulation of Heart Rates
The regulation of heart rate is a complex process controlled by the autonomic nervous system (ANS), hormonal influences, and intrinsic cardiac mechanisms. The ANS has two main components: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
The SNS increases heart rate through the release of norepinephrine and epinephrine, which act on beta-1 adrenergic receptors in the heart. This action increases the rate of depolarization in the sinoatrial (SA) node, the heart's...
The SNS increases heart rate through the release of norepinephrine and epinephrine, which act on beta-1 adrenergic receptors in the heart. This action increases the rate of depolarization in the sinoatrial (SA) node, the heart's...