Neurophysiological Evaluation of Training Effect on Cancer-Related Weakness

描述(申请人提供)：虚弱限制了许多癌症幸存者的行动能力，降低了他们的生活质量，特别是那些癌症晚期患者。早期的研究表明，高强度力量训练(HIST)对于获得肌肉力量是必不可少的。尽管参加HIST对更年轻、更健康的人来说没有什么困难，但对于许多体能有限的虚弱癌症幸存者来说，这样的训练令人生畏，也不安全。然而，近年来的证据表明，高强度训练(有意的肌肉收缩)结合不做或很少的体育锻炼，可以通过增加大脑对肌肉的指挥力来显著增强肌肉，这有助于提高运动单位的招募和激活水平。尽管高强度训练对肌肉强化的影响已经在健康的年轻人和老年人中得到认可，但对于它在改善虚弱患者的力量方面的应用尚不清楚，这些患者可能从参加这种类型的训练中受益最大，因为他们在进行训练时可能会面临困难。 传统的历史记录。此外，高精神努力训练导致力量增加现象背后的详细神经生理机制尚未确定。来自PI实验室的初步数据显示，虚弱的癌症患者接受高努力运动想象训练可以显着提高他们的力量。基于脑电的运动相关皮质电位测量显示，在这种训练之后，对目标肌肉的下行命令得到了增强。这些观察结果导致了我们的基本假设，即神经适应导致的训练诱导的力量增加不依赖于肌肉运动的强度；相反，它主要依赖于训练期间的自愿努力水平，而不是身体运动强度。这项研究的主要目的是通过训练虚弱的癌症幸存者进行高强度加中等强度(HEMI)和低强度结合中等强度(LEMI)肌肉练习来验证这一假说，并评估训练后的力量改善和潜在的神经可塑性。本研究的目的是确定HEMI和LEMI训练对握力和基于fMRI的脑连接水平的影响，fMRI调节下行指令和功能性脑-肌肉耦合(FBMC)以获得最大肌肉力量。据推测，HEMI训练将显着增加力量并提高皮质网络连接和fBMC的水平，但LEMI不会。研究结果将表明，HEMI训练是激发神经可塑性的有效方法，可以促进虚弱的乳腺癌幸存者的肌肉力量。虽然结果将从乳腺癌患者身上获得，但这种方法(HEMI训练)并不局限于自愿肌肉强化的患者群体。

DESCRIPTION (provided by applicant): Weakness limits mobility and diminishes quality of life in many cancer survivors, especially in those who suffer from late stage of cancer. Early research suggests that high-intensity strength training (HIST) is essential to gain muscle strength. Although participating in HIST posts little difficulties for younger and healthy individuals, such training is intimidating and unsafe for many weak cancer survivors with limited physical abilities. Evidence in recent years, however, has shown that training with high effort (intended muscle contraction) combined with no or little physical exercise can significantly strengthen muscle by increasing brain-to-muscle command, which helps improve motor unit recruitment and activation level. Although the effect of high-effort training on muscle strengthening has been recognized in healthy young and older adults, nothing is known regarding its application to improving strength in weak patients, individuals who may benefit most from participating in this type of training, given difficulties they may face when engaging in conventional HIST. Further, detailed neurophysiological mechanisms behind the phenomenon of high mental effort training- induced strength gain are yet to be determined. Preliminary data from the PI's laboratory show that cancer patients with weakness undergone high-effort motor imagery training can significantly improve their strength. EEG-based movement-related cortical potential measurement demonstrates enhanced descending command to target muscle following such training. These observations led to our fundamental hypothesis that training-induced strength gain resulting from neural adaptations is not dependent on intensity of muscle exercise; rather, it relies primarily on the level of voluntary effort during training regardless o physical exercise intensity. The major goal of this study is to test this hypothesis by training weak cancer survivors with high effort plus moderate intensity (HEMI) and low effort combined with moderate intensity (LEMI) muscle exercises and evaluate strength improvement and underlying neural plasticity after training. The Aims of the study are to determine the effects of HEMI and LEMI training on handgrip strength and level of fMRI-based brain connectivity that modulates the descending command and functional brain-muscle coupling (fBMC) for maximal muscle force. It is hypothesized that the HEMI training will significantly gain strength and elevat the level of cortical network connectivity and fBMC but the LEMI will not. The findings will show that HEMI training is an effective approach to provoke neural plasticity that promotes muscle strength in breast cancer survivors with weakness. Although the results will be acquired from breast cancer patients, the method (HEMI training) is not limited to this patient population for voluntary muscle strengthening.