确定肌电疲劳阈值以下单次访问运动试验
Summary
This protocol describes the electromyographic fatigue threshold which demarcates between nonfatiguing and fatiguing exercise workloads. This information could be used to develop a more individualized training program.
Abstract
从理论上讲，肌电图（EMG）疲劳阈是运动强度个人可以无限期地保持，而不需要招募其与增加的肌电振幅相关联的更多的运动单位。虽然不同的协议已被用于估计肌电疲劳阈它们需要多次访问这是不切实际的临床环境。在这里，我们提出了一个协议，用于估算周期测力肌电图疲劳阈值，需要一个单一的访问。这个协议是简单，方便，并在15-20分钟内完成，因此，具有将其转化为临床医生在运动处方可以使用工具的潜力。
Introduction
表面肌电图（EMG）是研究过程中等距1-3运动单位招聘，等速4-6，或连续7-10肌肉动作的一种非侵入性的方法。肌电图信号的振幅表示肌肉激活它由电机单元的数目激活的马达单元的燃烧率，或两者11。的肌电疲劳阈的概念被用来指示在其中个人可以无限期地行使不增加肌电振幅8的最高工作负荷。
重要的是要简要讨论的肌电疲劳阈原点。由DeVries医师等人 12的最初的研究涉及一种协议，它由多个（通常为3至4个）连续工作较量，其中肌电振幅对时间作图每个工作回合。然后，输出功率为作图从EMG幅度的斜率系数随时间RELA tionship，然后外推至零斜率（y截距）12。笔者原本12被称为该协议的实际工作能力，在疲劳阈值（PWCFT）。在另一项研究中，DeVries医师等 13间断使用一阵阵的工作，但使用的是线性回归找到第一动力输出，导致了肌电图振幅随时间的关系显著斜率。作者13也被称为该协议的PWCFT，开创了文学有些混乱。在随后的文章中，DeVries医师等 14修改他们早先的协议13，并制定了持续渐进的协议。肌电振幅对时间作图的每个功率输出和PWCFT被定义为输出功率最高的，导致在肌电振幅没有随时间的变化和功率输出最低，导致增加的EMG振幅随着时间的推移14的平均。
耳鼻喉科“>应当指出的是，预委会最初引入在20世纪50年代后期15,16和术语是同义的过多文献（过去，现在，和在不同的国家）检查在给定的工作负载17有氧能力，此外，这个词用在人体工程学和工业文献其中重点为期8个小时工作日内完成重复性动作工人一天到一天的工作效率，例如在一个组装厂18个人。术语肌电疲劳阈最初使用由Matsumoto和同事19它们改性的DeVries医师12协议，其中所述功率输出与所述EMG振幅对时间关系的斜率系数被绘制并外推至零斜率的点之后。最近，古费等人 20和布里斯科等人 8使用DeVries医师等人 14的方法和Matsumoto 等一个术语负于19操作性定义肌电图疲劳阈值。展望未来，我们建议长期EMG疲劳阈值来使用。因此，EMG振幅对时间的关系，绘制用于 每个输出功率并使用线性回归分析（ 图1）进行分析。为了估计肌电疲劳阈值时，功率输出最高与非显著（P> 0.05）的斜率和功率输出最低有显著（P <0.05）斜率被确定，然后计算平均值14。这个协议是简单，方便，并在15-20分钟内完成。此外，增量速率可以基于惯常的体力活动的个体的水平进行调制，并且因此具有在临床应用潜力。
Protocol
Representative Results
Discussion
我们在这里提出对确定神经肌肉股四头肌疲劳的方法肌肉股四头肌动态运动。这种方法提供了一个简单的和非侵入性的方式使用表面肌电信号。此外，该方法的通用性，研究人员可以使其适应于行使其他模式，如在跑步机20。
从理论上讲，对于强度等于或低于肌电疲劳阈参与者应能维持锻炼workbout无限期12,13。布里斯科等 8证实为周期测力肌电图…
Divulgations
The authors have nothing to disclose.
Acknowledgements
This project was funded by, in part, by start-up funds from Wayne State University to M.H. Malek.
Materials
| 839 E Monark cycle ergometer | Monark Exercise AB | 839 E | |
| Heart rate monitor | Polar | Polar H1 | |
| Laptop | Dell Inspiron | varies | any laptop computer with USB slots should work. |
| EMG amplifiers | BioPac Systems, Inc. | 100B | 100C are the latest version |
| Disposable EMG electrodes | BioPac Systems, Inc. | EL-500 | |
| Sandpaper | Home Depot | 9 in. x 11 in. 60 Grit course no-slip grip Advanced Sandpaper (3-Pack) |
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