scholarly journals Feedback-controlled stimulation enhances human paralyzed muscle performance

2006 ◽  
Vol 101 (5) ◽  
pp. 1312-1319 ◽  
Author(s):  
Richard K. Shields ◽  
Shauna Dudley-Javoroski ◽  
Keith R. Cole
Keyword(s):  
Electrical Stimulation ◽  
High Frequency ◽  
Neuromuscular Electrical Stimulation ◽  
Peak Torque ◽  
Open Loop ◽  
Muscle Performance ◽  
Constant Frequency ◽  
Extensive Training ◽  
Long Duration ◽  
Repetitive Stress

Chronically paralyzed muscle requires extensive training before it can deliver a therapeutic dose of repetitive stress to the musculoskeletal system. Neuromuscular electrical stimulation, under feedback control, may subvert the effects of fatigue, yielding more rapid and extensive adaptations to training. The purposes of this investigation were to 1) compare the effectiveness of torque feedback-controlled (FDBCK) electrical stimulation with classic open-loop constant-frequency (CONST) stimulation, and 2) ascertain which of three stimulation strategies best maintains soleus torque during repetitive stimulation. When torque declined by 10%, the FDBCK protocol modulated the base stimulation frequency in three ways: by a fixed increase, by a paired pulse (doublet) at the beginning of the stimulation train, and by a fixed decrease. The stimulation strategy that most effectively restored torque continued for successive contractions. This process repeated each time torque declined by 10%. In fresh muscle, FDBCK stimulation offered minimal advantage in maintaining peak torque or mean torque over CONST stimulation. As long-duration fatigue developed in subsequent bouts, FDBCK stimulation became most effective (∼40% higher final normalized torque than CONST). The high-frequency strategy was selected ∼90% of the time, supporting that excitation-contraction coupling compromise and not neuromuscular transmission failure contributed to fatigue of paralyzed muscle. Ideal stimulation strategies may vary according to the site of fatigue; this stimulation approach offered the advantage of online modulation of stimulation strategies in response to fatigue conditions. Based on stress-adaptation principles, FDBCK-controlled stimulation may enhance training effects in chronically paralyzed muscle.

scholarly journals Modulation of torque evoked by wide-pulse, high-frequency neuromuscular electrical stimulation and the potential implications for rehabilitation and training

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chris Donnelly ◽  
Jonathan Stegmüller ◽  
Anthony J. Blazevich ◽  
Fabienne Crettaz von Roten ◽  
Bengt Kayser ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
High Frequency ◽  
Neuromuscular Electrical Stimulation ◽  
Motor Units ◽  
Progressive Increase ◽  
Great Promise ◽  
Measured Parameter ◽  
Time Integral ◽  
Spinal Circuitry ◽  
Evoked Force

AbstractThe effectiveness of neuromuscular electrical stimulation (NMES) for rehabilitation is proportional to the evoked torque. The progressive increase in torque (extra torque) that may develop in response to low intensity wide-pulse high-frequency (WPHF) NMES holds great promise for rehabilitation as it overcomes the main limitation of NMES, namely discomfort. WPHF NMES extra torque is thought to result from reflexively recruited motor units at the spinal level. However, whether WPHF NMES evoked force can be modulated is unknown. Therefore, we examined the effect of two interventions known to change the state of spinal circuitry in opposite ways on evoked torque and motor unit recruitment by WPHF NMES. The interventions were high-frequency transcutaneous electrical nerve stimulation (TENS) and anodal transcutaneous spinal direct current stimulation (tsDCS). We show that TENS performed before a bout of WPHF NMES results in lower evoked torque (median change in torque time-integral: − 56%) indicating that WPHF NMES-evoked torque might be modulated. In contrast, the anodal tsDCS protocol used had no effect on any measured parameter. Our results demonstrate that WPHF NMES extra torque can be modulated and although the TENS intervention blunted extra torque production, the finding that central contribution to WPHF NMES-evoked torques can be modulated opens new avenues for designing interventions to enhance WPHF NMES.

scholarly journals Assessment of muscle activity using electrical stimulation and mechanomyography: a systematic review

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Raphael Uwamahoro ◽  
Kenneth Sundaraj ◽  
Indra Devi Subramaniam
Keyword(s):  
Electrical Stimulation ◽  
Processing Speed ◽  
Muscle Activity ◽  
Neuromuscular Electrical Stimulation ◽  
Voluntary Contraction ◽  
Electrical Signal ◽  
Muscle Performance ◽  
Inclusion Criteria ◽  
Activity Assessment ◽  
Experimental Protocols

AbstractThis research has proved that mechanomyographic (MMG) signals can be used for evaluating muscle performance. Stimulation of the lost physiological functions of a muscle using an electrical signal has been determined crucial in clinical and experimental settings in which voluntary contraction fails in stimulating specific muscles. Previous studies have already indicated that characterizing contractile properties of muscles using MMG through neuromuscular electrical stimulation (NMES) showed excellent reliability. Thus, this review highlights the use of MMG signals on evaluating skeletal muscles under electrical stimulation. In total, 336 original articles were identified from the Scopus and SpringerLink electronic databases using search keywords for studies published between 2000 and 2020, and their eligibility for inclusion in this review has been screened using various inclusion criteria. After screening, 62 studies remained for analysis, with two additional articles from the bibliography, were categorized into the following: (1) fatigue, (2) torque, (3) force, (4) stiffness, (5) electrode development, (6) reliability of MMG and NMES approaches, and (7) validation of these techniques in clinical monitoring. This review has found that MMG through NMES provides feature factors for muscle activity assessment, highlighting standardized electromyostimulation and MMG parameters from different experimental protocols. Despite the evidence of mathematical computations in quantifying MMG along with NMES, the requirement of the processing speed, and fluctuation of MMG signals influence the technique to be prone to errors. Interestingly, although this review does not focus on machine learning, there are only few studies that have adopted it as an alternative to statistical analysis in the assessment of muscle fatigue, torque, and force. The results confirm the need for further investigation on the use of sophisticated computations of features of MMG signals from electrically stimulated muscles in muscle function assessment and assistive technology such as prosthetics control.

Effect Of Neuromuscular Electrical Stimulation On Peak Torque Knee Joint

2014 ◽  
Vol 46 ◽  
pp. 671
Author(s):  
Flávia Medeiros ◽  
Amilton Vieira ◽  
Martim Bottaro ◽  
João Durigan
Keyword(s):  
Electrical Stimulation ◽  
Knee Joint ◽  
Neuromuscular Electrical Stimulation ◽  
Peak Torque

scholarly journals Quadriceps Femoris Muscle Torques and Fatigue Generated by Neuromuscular Electrical Stimulation With Three Different Waveforms

2001 ◽  
Vol 81 (7) ◽  
pp. 1307-1316 ◽  
Author(s):  
Yocheved Laufer ◽  
Julie Deanne Ries ◽  
Peter M Leininger ◽  
Gad Alon
Keyword(s):  
Electrical Stimulation ◽  
Mixed Model ◽  
Neuromuscular Electrical Stimulation ◽  
Quadriceps Femoris ◽  
Muscle Performance ◽  
Current Phase ◽  
Quadriceps Femoris Muscle ◽  
Male Subjects ◽  
Femoris Muscle ◽  
Female Subjects

Abstract Background and Purpose. Neuromuscular electrical stimulation is used by physical therapists to improve muscle performance. Optimal forms of stimulation settings are yet to be determined, as are possible sex-related differences in responsiveness to electrical stimulation. The objectives of the study were: (1) to compare the ability of 3 different waveforms to generate isometric contractions of the quadriceps femoris muscles of individuals without known impairments, (2) to compare muscle fatigue caused by repeated contractions induced by these same waveforms, and (3) to examine the effect of sex on muscle force production and fatigue induced by electrical stimulation. Subjects. Fifteen women and 15 men (mean age=29.5 years, SD=5.4, range=22–38) participated in the study. Methods. A portable battery-operated stimulator was used to generate either a monophasic or biphasic rectangular waveform. A stimulator that was plugged into an electrical outlet was used to generate a 2,500-Hz alternating current. Phase duration, frequency, and on-off ratios were kept identical for both stimulators. Participants did not know the type of waveform being used. Torque was measured using a computerized dynamometer: a maximal voluntary isometric contraction (MVIC) of the right quadriceps femoris muscle set at 60 degrees of knee flexion was determined during the first session. In each of the 3 testing sessions, torque of contraction and fatigue elicited by one waveform were measured. Order of testing was randomized. Torque elicited by electrical stimulation was expressed as a percentage of average MVIC. A mixed-model analysis of variance was used to determine the effect of stimulation and sex on strength of contraction and fatigue. Bonferroni-corrected post hoc tests were used to further distinguish between the effects of the 3 stimulus waveforms. Results. The results indicated that the monophasic and biphasic waveforms generated contractions with greater torque than the polyphasic waveform. These 2 waveforms also were less fatiguing. The torques from the maximally tolerated electrically elicited contractions were greater for the male subjects than for the female subjects. Discussion and Conclusion. Muscle torque and fatigue of electrically induced contractions depend on the waveform used to stimulate the contraction, with monophasic and biphasic waveforms having an advantage over the polyphasic waveform. All tested waveforms elicited, on average, stronger contractions in male subjects than in female subjects when measured as a percentage of MVIC.

Comparison of peak torque, intensity and discomfort generated by neuromuscular electrical stimulation of low and medium frequency

2013 ◽  
Vol 21 (2) ◽  
pp. 167-173 ◽  
Author(s):  
Thiago Yukio Fukuda ◽  
Freddy Beretta Marcondes ◽  
Nayra dos Anjos Rabelo ◽  
Rodrigo Antunes de Vasconcelos ◽  
Claudio Cazarini Junior
Keyword(s):  
Electrical Stimulation ◽  
Neuromuscular Electrical Stimulation ◽  
Peak Torque ◽  
Medium Frequency ◽  
Stimulation Of

Influence of wide-pulse neuromuscular electrical stimulation frequency and superimposed tendon vibration on occurrence and magnitude of extra torque

2021 ◽  
Author(s):  
Loïc Espeit ◽  
Vianney Rozand ◽  
Guillaume Y. Millet ◽  
Julien Gondin ◽  
Nicola A. Maffiuletti ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
High Frequency ◽  
Plantar Flexion ◽  
Neuromuscular Electrical Stimulation ◽  
Low Frequency ◽  
Force Production ◽  
Voluntary Contraction ◽  
Tendon Vibration ◽  
Afferent Pathways ◽  
Design Decisions

Low-frequency and high-frequency wide-pulse neuromuscular electrical stimulation (NMES) can generate extra-torque (ET) via afferent pathways. Superimposing tendon vibration (TV) to NMES can increase the activation of these afferent pathways and favour ET generation. Knowledge of the characteristics of ET is essential to implement these stimulation paradigms in clinical practice. Thus, we aimed at investigating the effects of frequency and TV superimposition on the occurrence and magnitude of ET in response to wide-pulse NMES. NMES-induced isometric plantar flexion torque was recorded in 30 healthy individuals who performed five NMES protocols: wide-pulse low-frequency (1 ms; 20 Hz; WPLF) and wide-pulse high-frequency (1 ms; 100 Hz; WPHF) without and with superimposed TV (1 mm; 100 Hz) and conventional NMES (50 µs; 20 Hz; reference protocol). Each NMES protocol began with an adjustment of NMES intensity in order to reach 10% of maximal voluntary contraction then consisted of three 20-s trains interspersed by 90 s of rest. The ET occurrence was similar for WPLF and WPHF (p=0.822). In the responders, the ET magnitude was greater for WPHF than WPLF (p<0.001). There was no effect of superimposed TV on ET characteristics. This study reported an effect of NMES frequency on ET magnitude, whereas TV superimposition did not affect this parameter. In the context of our experimental design decisions, the present findings question the clinical use of wide-pulse NMES and its combination with superimposed TV. Yet, further research is needed in order to maximize force production through the occurrence and magnitude of ET.

Sign in / Sign up

Export Citation Format

Share Document