Inter- and Intra-Individual Differences in EMG and MMG during Maximal, Bilateral, Dynamic Leg Extensions
Abstract
:1. Introduction
2. Materials and Methods
2.1. Subjects
2.2. Protocol
2.3. Electromyographic, Mechanomyographic, and Force Signal Acquisition
2.4. Statistical Analysis
3. Results
3.1. Torque Response
3.2. EMG Response
3.3. MMG Response
4. Discussion
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Subjects | R EMG AMP | L EMG AMP | R EMG MPF | L EMG MPF | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Model | Correlation | p-Value | Model | Correlation | p-Value | Model | Correlation | p-Value | Model | Correlation | p-Value | |
1 | – | – | – | – | – | – | Quadratic | −0.733 | 0.002 | Quadratic | −0.563 | 0.047 |
2 | Quadratic | 0.685 | 0.006 | Quadratic | 0.831 | <0.001 | Quadratic | −0.733 | 0.002 | Quadratic | −0.721 | 0.003 |
3 | – | – | – | – | – | – | – | – | – | Quadratic | 0.579 | 0.039 |
4 | – | – | – | – | – | – | – | – | – | – | – | – |
5 | – | – | – | Quadratic | 0.590 | 0.033 | Quadratic | −0.949 | <0.001 | Quadratic | −0.749 | 0.001 |
6 | – | – | – | – | – | – | Quadratic | 0.870 | <0.001 | Quadratic | −0.585 | 0.035 |
7 | Quadratic | 0.749 | 0.001 | – | – | – | Quadratic | −0.805 | <0.001 | Linear | −0.525 | 0.021 |
8 | – | – | – | – | – | – | – | – | – | Quadratic | −0.619 | 0.021 |
9 | – | – | – | Quadratic | 0.562 | 0.048 | Quadratic | −0.700 | 0.005 | Quadratic | −0.739 | 0.002 |
10 | – | – | – | – | – | – | – | – | – | Quadratic | −0.685 | 0.006 |
11 | – | – | – | – | – | – | Quadratic | −0.715 | 0.003 | Quadratic | −0.633 | 0.017 |
12 | Linear | 0.549 | 0.015 | – | – | – | Quadratic | −0.778 | 0.001 | Quadratic | −0.718 | 0.003 |
13 | – | – | – | – | – | – | Quadratic | −0.767 | 0.001 | – | – | – |
Composite | Quadratic | 0.749 | 0.001 | Quadratic | 0.793 | 0.002 | Quadratic | −0.953 | <0.001 | Quadratic | −0.913 | <0.001 |
Subjects | R MMG AMP | L MMG AMP | R MMG MPF | L MMG MPF | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Model | Correlation | p-Value | Model | Correlation | p-Value | Model | Correlation | p-Value | model | Correlation | p-Value | |
1 | – | – | – | Linear | −0.498 | 0.030 | Quadratic | −0.603 | 0.020 | – | – | – |
2 | – | – | – | – | – | – | – | – | – | Quadratic | −0.658 | 0.011 |
3 | – | – | – | – | – | – | – | – | – | – | – | – |
4 | Quadratic | −0.769 | 0.001 | Quadratic | −0.679 | 0.001 | – | – | – | – | – | – |
5 | – | – | – | – | – | – | Linear | −0.506 | 0.027 | – | – | – |
6 | Quadratic | −0.804 | <0.001 | Quadratic | −0.759 | 0.001 | Linear | 0.480 | 0.037 | Quadratic | 0.779 | 0.001 |
7 | – | – | – | Quadratic | −0.569 | 0.044 | – | – | – | – | – | – |
8 | – | – | – | Quadratic | −0.867 | <0.001 | – | – | – | – | – | – |
9 | – | – | – | Quadratic | −0.651 | 0.012 | – | – | – | – | – | – |
10 | Quadratic | 0.615 | 0.022 | Quadratic | 0.637 | 0.015 | Quadratic | −0.792 | <0.001 | – | – | – |
11 | – | – | – | Linear | −0.469 | 0.043 | – | – | – | – | – | – |
12 | Quadratic | 0.789 | <0.001 | – | – | – | Quadratic | −0.890 | <0.001 | – | – | – |
13 | Quadratic | −0.564 | 0.047 | – | – | – | – | – | – | – | – | – |
Composite | Quadratic | −0.864 | <0.001 | Quadratic | −0.933 | <0.001 | Linear | −0.547 | 0.015 | – | – | – |
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Anders, J.P.V.; Smith, C.M.; Keller, J.L.; Hill, E.C.; Housh, T.J.; Schmidt, R.J.; Johnson, G.O. Inter- and Intra-Individual Differences in EMG and MMG during Maximal, Bilateral, Dynamic Leg Extensions. Sports 2019, 7, 175. https://doi.org/10.3390/sports7070175
Anders JPV, Smith CM, Keller JL, Hill EC, Housh TJ, Schmidt RJ, Johnson GO. Inter- and Intra-Individual Differences in EMG and MMG during Maximal, Bilateral, Dynamic Leg Extensions. Sports. 2019; 7(7):175. https://doi.org/10.3390/sports7070175
Chicago/Turabian StyleAnders, John Paul V., Cory M. Smith, Joshua L. Keller, Ethan C. Hill, Terry J. Housh, Richard J. Schmidt, and Glen O. Johnson. 2019. "Inter- and Intra-Individual Differences in EMG and MMG during Maximal, Bilateral, Dynamic Leg Extensions" Sports 7, no. 7: 175. https://doi.org/10.3390/sports7070175