サイクリング中に適用される逆側側側側側側痛による皮質運動および神経筋機能の調節の研究
Jenny Zhang1, Niloofar Honarvar1, Arezou Habibirad2
1Faculty of Kinesiology, University of Calgary, Calgary, Canada.
Scandinavian journal of medicine & science in sports
|August 26, 2025
まとめ
実験的な痛みは 運動の耐久性を損なう 感覚の努力と疲労を増加させる. しかし,神経筋機能には影響しませんが,痛みに応じて皮質の阻害を変化させることができます.
科学分野:
- 運動 生理学
- 神経科学
- 痛みに関する研究
背景:
- 痛みは運動能力に悪影響を及ぼします.
- 長期間の運動中の運動制御に対する実験的な痛みの特異的な影響は完全に理解されていません.
- 痛みの影響について調べる 脊髄刺激と抑制 徹底的なサイクリングは不可欠です.
研究 の 目的:
- 運動している肢体や運動していない肢体への実験的な痛みが神経筋機能,皮質脊髄刺激性,抑制を調節するかどうかをテストする.
- 長時間サイクリング中に痛みが知覚と心呼吸反応を悪化させるかどうかを判断する.
- これらの効果の時間経過を徹底的に検討する.
主な方法:
- 10人の健康な成人は,60パーセントのピーク出力で疲労まで3回の単足サイクリングセッションを受けた:コントロール (痛みなし),対側痛 (CONTRA),および対側痛 (IPSI).
- トランスクラニアル磁気刺激 (TMS) は5分毎に皮質脊髄刺激 (MEP·Mmax−1) と皮質内抑制 (SICI,LICI) を評価するために使用されました.
- 最大の自発的な収縮 (MVC),自発的な活性化,および知覚/心肺反応が記録された.
主要な成果:
- コントロールと比較して,CONTRAおよびIPSI条件の両方で,故障までの時間は著しく短縮されました.
- MVCの力,自発的な活性化,および休息時の震動力は,条件によって異なるものではありません.
- 短期間隔内皮質阻害 (SICI) はCONTRAでは増加し,長期間隔内皮質阻害 (LICI) はCONTRAでは増加したが,IPSIでは減少した. 痛み知覚,疲労,および労力の評価は両方の痛み状態で高かった.
結論:
- 実験的な痛みは,長時間サイクリング中に知覚反応 (疲労,努力) を高め,耐久性を低下させます.
- 神経筋機能 (MVC,自発的活性化) は,痛みにもかかわらず無傷のままです.
- 痛みを適用する場所は 皮質の抑制を差異的に調節し 中枢神経系の適応を示唆しています
関連する概念動画
01:26Cross-bridge Cycle
125.1K
As muscle contracts, the overlap between the thin and thick filaments increases, decreasing the length of the sarcomere—the contractile unit of the muscle—using energy in the form of ATP. At the molecular level, this is a cyclic, multistep process that involves binding and hydrolysis of ATP, and movement of actin by myosin.
125.1K
01:29Relaxation of Skeletal Muscles
9.5K
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....
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....
9.5K
01:24Muscle Recovery and Fatigue
5.0K
Muscle fatigue refers to the decline in a muscle's ability to maintain the force of contraction after prolonged activity. It primarily stems from changes within muscle fibers. Even before experiencing muscle fatigue, one may feel tired and have the urge to stop the activity. This response, known as central fatigue, occurs due to changes in the central nervous system, namely the brain and spinal cord. While there is no single mechanism that induces fatigue, it may serve as a protective...
5.0K
01:20Motor Unit Stimulation
4.9K
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...
4.9K
01:22Muscle Stimulation Frequency
5.1K
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...
5.1K