MENTAL EFFORT EFFECT ON LARGE MUSCLE STRENGTHENING

精神努力对大肌力量的影响

• 批准号: 6521095
• 负责人: GUANG H YUE
• 金额: $ 21.9万
• 依托单位: CLEVELAND CLINIC FOUNDATION
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-27 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6521095
• 关键词: biomechanics; brain electrical activity; clinical research; elbow; electroencephalography; electromyography; exercise; functional ability; functional magnetic resonance imaging; human old age (65+); human subject; leg; muscle contraction; muscle strength; neural information processing; neuromuscular function; psychomotor function

It is well known that to strengthen a muscle one should perform training involving heavy loads or resistance. Recently we have found that substantial voluntary strength gains can be achieved with training involving low resistance but strong mental effort. In contrast, individuals who trained with the same low-intensity contractions but with low mental effort had no improvement in strength. Based on these preliminary findings, we hypothesize that muscle strength improvements depend primarily on the level of mental effort during training, not the training intensity (resistance) per se. The reason that high-intensity training always increases strength is because mental effort is high during high-intensity muscle contractions. Aim 1 of the project is to compare the effects of training with different levels of mental effort on the improvement in muscle strength. Four groups of elderly subjects (greater than or equal to 65 years) will participate in a 12-week training study involving elbow-flexor muscles. One group will be trained with an intensity near the level of maximal voluntary contraction (MVC group); a second group will be trained with high mental-effort, low muscle-intensity elbow-flexion contractions (LME group); and the fourth (control) group will not be trained will participate in the strength tests. We expect that the strength improvement after training will be: MVC group > HME group > LME group = control group. We also expect that the strength increase in the MVC and HME groups will result in an improvement in daily living function. Aim 2 is determine the neural mechanisms underlying muscle strength improvements. We hypothesize that an increase in the central nervous system (CNS) drive is the primary mechanism that mediates strength improvements induced by low-intensity training (HME group). To evaluate the CNS drive, four measurements will be made using the same subjects and groups as in Ami 1: brain activation level examined by functional MRI (fMRI) and EEG-derived motor activity-related cortical potential (MRCP), surface EMG signals, and the MRI T2 relaxation time obtained from the trained muscles. We expect to find that after training: (1) the brain activation level (fMRI and MRCP), EMG, and MRI T2 will significantly increase in the MVC and HME groups; and (2) the amplitude of increases in these measurements will be: MVC group = HME group > LME group = control group. The knowledge gained from these studies will substantially advance the current understanding of mechanisms underlying human voluntary muscle strengthening and will have direct application in neuromuscular rehabilitation for older adults and individuals who are physically handicapped and unable to perform repeated, forceful muscle contractions.

众所周知，为了加强肌肉，一个人应该进行包括大负荷或阻力的训练。最近，我们发现，通过低阻力但强大的精神努力的训练，可以实现实质性的自愿力量增长。相比之下，接受同样的低强度收缩训练，但脑力不强的个体在力量上没有提高。基于这些初步发现，我们假设肌肉力量的提高主要取决于训练期间的精神努力水平，而不是训练强度(阻力)本身。高强度训练之所以总能增加力量，是因为在高强度肌肉收缩时，脑力劳动很大。该项目的目标1是比较不同脑力水平的训练对提高肌肉力量的效果。四组老年受试者(大于或等于65岁)将参加为期12周的肘屈肌训练研究。其中一组将以接近最大自愿收缩水平的强度进行训练(MVC组)；第二组将进行高脑力、低肌肉强度的屈肘收缩训练(LME组)；第四组(对照组)将不进行训练，将参加力量测试。我们预计训练后的力量提高情况为：MVC组和GT组；HME组和GT组；LME组=对照组。我们还预计，MVC和HME组力量的增加将导致日常生活功能的改善。目标2是确定肌肉力量改善的神经机制。我们假设，中枢神经系统(CNS)驱动力的增加是调节低强度训练(HME组)导致的力量提高的主要机制。为了评估CNS驱动，将使用与AMI 1相同的受试者和组进行四项测量：功能磁共振成像(FMRI)和脑电衍生运动活动相关皮质电位(MRCP)检测的脑激活水平、表面肌电信号和从训练肌肉获得的磁共振T2松弛时间。我们期望在训练后发现：(1)MVC组和HME组的脑激活水平(fMRI和MRCP)、EMG和MRI T2将显著增加；(2)这些测量的增加幅度将是：MVC组=HME组和GT；LME组=对照组。从这些研究中获得的知识将极大地促进目前对人类自愿肌肉增强机制的理解，并将直接应用于老年人和身体残疾且无法进行反复、有力肌肉收缩的个人的神经肌肉康复。

项目成果

Dependence of finger flexion force on the posture of the nonperforming fingers during key pressing tasks.

在按键任务期间，手指屈曲力对不良手指姿势的依赖性。

• DOI: 10.1080/00222890209601951
• 发表时间: 2002
• 期刊: Journal of motor behavior.
• 作者: Li,Zong-Ming;Yue,GuangH
• 通讯作者: Yue,GuangH

Selective atrophy of left hemisphere and frontal lobe of the brain in old men.

老年人大脑左半球和额叶选择性萎缩。

• DOI: 10.1093/gerona/60.2.165
• 发表时间: 2005
• 期刊: The journals of gerontology. Series A, Biological sciences and medical sciences
• 作者: Shan,ZuY;Liu,JingZ;Sahgal,Vinod;Wang,Bin;Yue,GuangH
• 通讯作者: Yue,GuangH