Data for: Intermuscular Coherence between Surface EMG Signals recorded with Monopolar and Bipolar EMG Systems during Squatting

This dataset contains raw EMG / goniometer data as well as a processed data sheet from a study with the research question how different EMG recording techniques affect the intermuscular coherence between surface EMG signals.
It was hypothesized that bipolar EMG signals would show a lower EMG-EMG coherence compared to monopolar signals due to inevitable errors in electrode alignment when aligning the sensors with the muscle fiber direction.

16 participants (12 male, 4 female, young, active adults) are included in this analysis. The muscles investigated were vastus lateralis and medialis and the investigated movement tasks were series of bipedal squats for 90 seconds (first trial stable on the ground, second trial stable on the ground, third trial unstable on a BOSU ball.

The main findings are that the intermuscular coherence between vastus lateralis and medialis was indeed reduced in the bipolar compared to monopolar recordings. Furthermore, coherence below 40 Hz was increased during unstable squatting and the monopolar current and bipolar potential systems were most sensitive to this change while the monopolar potential recordings showed low sensitivity.

Content of files:
1) "2018-04-EMG-EMG intermuscular coherence and EMG intensities" contains an Excel file with all averages across squats and subjects for each of the recording systems.
2) "Raw Data" contains a Matlab .mat file with the raw EMG data from each system and goniometre data representing the corresponding knee flexion angle during squatting.
The .mat file contains a cell array with 16 cells, one for each subject.
The subject-specific cells contain a 3x3 cell array, rows for recording systems (bipolar potential, monopolar potential, monopolar current), columns for trials (stable squatting 1, stable squatting 2, unstable squatting).
Each cell contains three data columns (VL EMG, VM EMG, goniometer data in Voltage).

本数据集收录了原始的肌电图/关节角测量仪数据以及一项研究的数据处理表，研究主题为不同肌电图记录技术如何影响表面肌电图信号之间的肌肉间相干性。研究假设，由于在将传感器与肌纤维方向对齐时电极对齐的不可避免误差，双极肌电图信号相较于单极信号将表现出更低的肌电图-肌电图相干性。分析中纳入了16名参与者（其中男性12名，女性4名，均为年轻活跃的成年人）。研究调查的肌肉包括股外侧肌和股内侧肌，所研究的运动任务为一系列持续90秒的双足蹲起（第一轮在稳定地面上进行，第二轮在稳定地面上进行，第三轮在BOSU球上不稳定进行）。主要发现是，相较于单极记录，股外侧肌与股内侧肌之间的肌肉间相干性在双极记录中确实有所降低。此外，在不稳定蹲起过程中，40 Hz以下的相干性有所增加，而单极电流和双极电位系统对此变化最为敏感，单极电位记录则表现出低敏感性。文件内容如下：
1) '2018-04-EMG-EMG intermuscular coherence and EMG intensities' 包含一个Excel文件，其中记录了所有蹲起和受试者对于每个记录系统的平均值。
2) 'Raw Data' 包含一个Matlab .mat文件，其中包含每个系统的原始肌电图数据和代表蹲起过程中相应膝关节屈曲角度的关节角测量仪数据。该.mat文件包含一个包含16个单元的单元数组，每个单元对应一名受试者。受试者特定的单元包含一个3x3的单元数组，行代表记录系统（双极电位、单极电位、单极电流），列代表试验（稳定蹲起1、稳定蹲起2、不稳定蹲起）。每个单元包含三个数据列（VL肌电图、VM肌电图、电压表示的关节角测量仪数据）。