Muscles alive-their functions revealed by electromyography

doi:10.1249/00005768-197621000-00002

Journal Article•DOI•

Muscles alive-their functions revealed by electromyography

21 Jan 1976-Medicine and Science in Sports and Exercise-Vol. 8, Iss: 1

About: This article is published in Medicine and Science in Sports and Exercise.The article was published on 1976-01-21. It has received 1237 citations till now. The article focuses on the topics: Electromyography.

...read moreread less

Citations

PDF

Open Access

More filters

Journal Article•DOI•

Increased rate of force development and neural drive of human skeletal muscle following resistance training

[...]

Per Aagaard¹, Erik B. Simonsen², Jesper L. Andersen, Peter Magnusson¹, Poul Dyhre-Poulsen - Show less +1 more•Institutions (2)

University of Copenhagen¹, Panum Institute²

01 Oct 2002-Journal of Applied Physiology

TL;DR: Increases in explosive muscle strength (contractile RFD and impulse) were observed after heavy-resistance strength training, which could be explained by an enhanced neural drive, as evidenced by marked increases in EMG signal amplitude and rate of EMG rise in the early phase of muscle contraction.

...read moreread less

Abstract: The maximal rate of rise in muscle force [rate of force development (RFD)] has important functional consequences as it determines the force that can be generated in the early phase of muscle contraction (0-200 ms). The present study examined the effect of resistance training on contractile RFD and efferent motor outflow ("neural drive") during maximal muscle contraction. Contractile RFD (slope of force-time curve), impulse (time-integrated force), electromyography (EMG) signal amplitude (mean average voltage), and rate of EMG rise (slope of EMG-time curve) were determined (1-kHz sampling rate) during maximal isometric muscle contraction (quadriceps femoris) in 15 male subjects before and after 14 wk of heavy-resistance strength training (38 sessions). Maximal isometric muscle strength [maximal voluntary contraction (MVC)] increased from 291.1 +/- 9.8 to 339.0 +/- 10.2 N. m after training. Contractile RFD determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction increased from 1,601 +/- 117 to 2,020 +/- 119 (P < 0.05), 1,802 +/- 121 to 2,201 +/- 106 (P < 0.01), 1,543 +/- 83 to 1,806 +/- 69 (P < 0.01), and 1,141 +/- 45 to 1,363 +/- 44 N. m. s(-1) (P < 0.01), respectively. Corresponding increases were observed in contractile impulse (P < 0.01-0.05). When normalized relative to MVC, contractile RFD increased 15% after training (at zero to one-sixth MVC; P < 0.05). Furthermore, muscle EMG increased (P < 0.01-0.05) 22-143% (mean average voltage) and 41-106% (rate of EMG rise) in the early contraction phase (0-200 ms). In conclusion, increases in explosive muscle strength (contractile RFD and impulse) were observed after heavy-resistance strength training. These findings could be explained by an enhanced neural drive, as evidenced by marked increases in EMG signal amplitude and rate of EMG rise in the early phase of muscle contraction.

...read moreread less

1,499 citations

Cites methods from "Muscles alive-their functions revea..."

...During the later process of analysis, the EMG signals were digitally high-pass filtered by using a fourth-order, zero-lag Butterworth filter with a 5-Hz cutoff frequency (48), followed by a moving root-mean-square filter with a time constant of 50 ms (10)....
[...]

Journal Article•DOI•

Human movement analysis using stereophotogrammetry. Part 1: theoretical background.

[...]

Aurelio Cappozzo, Ugo Della Croce¹, Alberto Leardini, Lorenzo Chiari•Institutions (1)

University of Sassari¹

01 Feb 2005-Gait & Posture

TL;DR: An effort to systematize the different theoretical and experimental approaches to the problems involved and related nomenclatures is needed to facilitate data and knowledge sharing, and to provide renewed momentum for the advancement of human movement analysis.

...read moreread less

892 citations

Cites methods from "Muscles alive-their functions revea..."

...Electrical activity of muscles is recorded through electromyography [3]....
[...]

Journal Article•DOI•

Sampling, noise-reduction and amplitude estimation issues in surface electromyography

[...]

Edward A. Clancy¹, Evelyn Morin², Roberto Merletti³•Institutions (3)

Worcester Polytechnic Institute¹, Queen's University², Polytechnic University of Turin³

01 Feb 2002-Journal of Electromyography and Kinesiology

TL;DR: Data acquisition and signal processing issues relative to producing an amplitude estimate of surface EMG, and methods for estimating the amplitude of the EMG are reviewed.

...read moreread less

586 citations

Cites background from "Muscles alive-their functions revea..."

...Keywords: Artefact rejection; Electromyography; EMG; EMG amplitude; Measurement noise; Noise; Surface EMG...
[...]

Journal Article•DOI•

Core stability and its relationship to lower extremity function and injury.

[...]

John D. Willson¹, Christopher P. Dougherty, Mary Lloyd Ireland, Irene McClay Davis•Institutions (1)

University of Delaware¹

01 Sep 2005-Journal of The American Academy of Orthopaedic Surgeons

TL;DR: Current evidence suggests that decreased core stability may predispose to injury and that appropriate training may reduce injury, and can be tested using isometric, isokinetic, and isoinertial methods.

...read moreread less

Abstract: Core stability may provide several benefits to the musculoskeletal system, from maintaining low back health to preventing knee ligament injury. As a result, the acquisition and maintenance of core stability is of great interest to physical therapists, athletic trainers, and musculoskeletal researchers. Core stability is the ability of the lumbopelvic hip complex to prevent buckling and to return to equilibrium after perturbation. Although static elements (bone and soft tissue) contribute to some degree, core stability is predominantly maintained by the dynamic function of muscular elements. There is a clear relationship between trunk muscle activity and lower extremity movement. Current evidence suggests that decreased core stability may predispose to injury and that appropriate training may reduce injury. Core stability can be tested using isometric, isokinetic, and isoinertial methods. Appropriate intervention may result in decreased rates of back and lower extremity injury.

...read moreread less

575 citations

Journal Article•DOI•

Differences in hip kinematics, muscle strength, and muscle activation between subjects with and without patellofemoral pain.

[...]

Richard B. Souza¹, Christopher M. Powers•Institutions (1)

University of California, San Francisco¹

01 Jan 2009-Journal of Orthopaedic & Sports Physical Therapy

TL;DR: The increased activation of the gluteus maximus in individuals with PFP suggests that these subjects were attempting to recruit a weakened muscle, perhaps in an effort to stabilize the hip joint.

...read moreread less

Abstract: Study Design Controlled laboratory study using a cross-sectional design. Objectives To determine whether females with patellofemoral pain (PFP) demonstrate differences in hip kinematics, hip muscle strength, and hip muscle activation patterns when compared to pain-free controls. Background It has been proposed that abnormal hip kinematics may contribute to the development of PFP. However, research linking hip function to PFP remains limited. Methods and Measures Twenty one females with PFP and 20 pain-free controls participated in this study. Hip kinematics and activity level of hip musculature were obtained during running, a drop jump, and a step-down maneuver. Isometric hip muscle torque production was quantified using a multimodal dynamometer. Group differences were assessed across tasks, using mixed-design 2-way analyses of variance and independent t tests. Results When averaged across all 3 activities, females with PFP demonstrated greater peak hip internal rotation compared to the control group (mea...

...read moreread less

553 citations

Cites background or methods from "Muscles alive-their functions revea..."

...Individuals with PFP were excluded from participation if they reported any of the following: (1) previous history of knee surgery, (2) history of traumatic patellar demonstrated excessive hip adduction and internal rotation (based on visual observation), as well as weakness of the hip extensors and abductors....
[...]
...The control group was selected based on the same criteria as the experimental group, except that subjects had none of the following: (1) history or diagnosis of knee pathology or trauma, (2) current knee pain or effusion, (3) knee pain with any of the activities described for the individuals in the PFP group, and (4) any condition that would influence gait....
[...]
...18,19 Only those subjects meeting the following criteria were admitted to the experimental group: (1) pain located specifically around the patellofemoral articulation (vague or localized); (2) readily reproducible pain (3 out of 10 on a visual analog scale) with at least 2 of the following functional activities commonly associated with PFP: stair ascent or descent, squatting, kneeling, prolonged sitting, or isometric quadriceps contraction; and (3) reports of pain greater than 3 months’ duration....
[...]

Collapse

Muscles alive-their functions revealed by electromyography

Citations

Cites methods from "Muscles alive-their functions revea..."

Cites methods from "Muscles alive-their functions revea..."

Cites background from "Muscles alive-their functions revea..."

Cites background or methods from "Muscles alive-their functions revea..."

Related Papers (5)