Dependence of Muscle Torque of Ankle Plantar and Dorsal Flexors on Different Ankle Angles

2018 ◽  
Vol 1 (80) ◽  
Author(s):  
Rima Solianik ◽  
Vaida Aleknavičiūtė ◽  
Zita Andrijauskaitė ◽  
Algimantas Putramentas ◽  
Gintarė Dargevičiūtė ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Maximal Voluntary Contraction ◽  
Plantar Flexion ◽  
Muscle Length ◽  
Voluntary Contraction ◽  
Calf Muscle ◽  
Muscle Torque ◽  
Ankle Angle ◽  
O 15 ◽  
The Relationship

Research background and hypothesis. There is much research information about the relationship between the knee joint angle and the quadriceps muscle torque (Mohamed et al., 2002), but still we lack evidence about the relationship between ankle angle and calf muscle torque. Research aim. The purpose of this research was to establish the dependence of maximal voluntary contraction (MVC) and electrical stimulation (ES)-evoked torque and calf muscle electrical activity (EMG) on different ankle plantar and dorsal fl exion angles. We hypothesized that the calf muscle MVC and ES-evoked torque as well as muscle EMG amplitude would increase with increasing muscle length (i. . increasing ankle angle).Research methods. The subjects in the research were ten non-trained men. Calf plantar and dorsal fl exors muscle ES and MVC torque were tested at eight different ankle angles (–25 o ; –15 o ; –5 o ; 0 o ; 15 o ; 25 o ; 35 o ; 45 o ) which were chosen in randomized sequence. The tibialis anterior, soleus, gastrocnemius lateralis and medialis muscle EMG were measured during muscle MVC.Research results. The results showed that the highest ES-evoked and MVC developed torque of plantar fl exion muscles was at –25° ankle angle (149.1 ± 31.6 N·m and 207.8 ± 38.1 N·m, respectively), while the highest dorsal fl exion MVC muscle torque was at 25° ankle angle (47.2 ± 8.1 N·m). However, dorsal fl exion muscle MVC torque increased with the muscle length only until 25° ankle angle. Discussion and conclusions. Plantar flexion muscle electrical stimulation evoked and plantar / dorsal fl exion muscle maximal voluntary contraction torques are highest at that ankle angle where muscle length is the longest.Keywords: maximal voluntary contraction, electrical stimulation, EMG.

scholarly journals Impact of Physiotherapy on the Calf Muscle Torque Variability after Achilles Tendon Rupture

2020 ◽  
Vol 2 (5) ◽  
Author(s):  
Vaida Aleknavičiūtė ◽  
Rima Solianik ◽  
Dovilė Kielė ◽  
Laimutis Škikas ◽  
Nerijus Masiulis ◽  
...  
Keyword(s):  
Muscle Strength ◽  
Achilles Tendon ◽  
Maximal Voluntary Contraction ◽  
Tendon Rupture ◽  
Achilles Tendon Rupture ◽  
Voluntary Contraction ◽  
Calf Muscle ◽  
Muscle Torque ◽  
Maximal Voluntary Contraction Torque ◽  
Flexion And Extension

It has been established that muscle torque variability determines movement stability during the task [1]. Calf muscle weakness, ankle range of motion reduction and postural misbalance are common pathological limitations after Achilles tendon rupture (ATR). Most studies analyse rehabilitation influence for muscle strength and body balance, but there is a lack of information about calf muscle torque variability. The aim of the study was to determine ankle plantar flexion and dorsal flexion muscle maximal voluntary contraction torque and variability Q. Organization and methods. We measured five males, (aged 29 ± 6) after 6.5 – week surgery of ATR. Participants performed isometric ankle flexion and extension force with injured and non-injured legs. Muscles maximal voluntary contraction (MVC) torque and torque variability were measured at –15°; 0°; 15° angles. The variability of target force was 20% of MVC torque. Rehabilitation programme consisted of balance, muscle strength and stretching exercises. Calf muscle MVC torque and variability were observed before and after 8-week rehabilitation. The results of the research. We determined that after physiotherapy the injured and the non-injured leg isometric ankle flexion and extension muscle MVC torque increased and muscle torque variability decreased.Keywords: muscle torque variability, isometric maximal voluntary contraction torque, rehabilitation suformavimas.

scholarly journals Velocity of the muscle tendon unit is sex-dependent and not altered with acute static stretch

2018 ◽  
Vol 43 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Carey L. Simpson ◽  
Rowan R. Smart ◽  
Dylan E.E. Melady ◽  
Jennifer M. Jakobi
Keyword(s):  
Plantar Flexion ◽  
Voluntary Contraction ◽  
Voluntary Activation ◽  
Plantar Flexors ◽  
Shortening Velocity ◽  
Static Stretch ◽  
Twitch Interpolation ◽  
Tendon Lengthening ◽  
The Individual ◽  
The Relationship

Contraction velocity of a muscle tendon unit (MTU) is dependent upon the interrelationship between fascicles shortening and the tendon lengthening. Altering the mechanical properties of these tissues through a perturbation such as static stretching slows force generation. Females, who have inherently greater compliance compared with males, have slower velocity of MTU components. The addition of a static stretch might further exacerbate this sex difference. The purpose of this study was to investigate the velocity of fascicle shortening and tendon lengthening in males and females during isometric maximal voluntary contraction (MVC) of the plantar flexors prior to and following an acute static stretch. The MTU was imaged with ultrasound and voluntary activation tested with twitch interpolation for the 5-s plantar flexion MVC, which proceeded and followed an acute stretch. For the 3-min stretch the ankle was passively rotated to maximal dorsi-flexion. The males were stronger (128.71 ± 7.88 Nm) than the females (89.92 ± 4.70 Nm) but voluntary activation did not differ. Tendon lengthening velocity (p = 0.001) and fascicle shortening velocity (p = 0.01) were faster in males than females. Tendon velocity was positively and significantly correlated with fascicle velocity, (r2 = 0.307, p = 0.02). Although sex was significant as a predictor (p = 0.05) time was not independently significant. Thus, stretch did not alter this relationship in either sex (p = 0.6). The velocity of the individual components of the MTU is slower in females when compared with males; however, acute stretch does not alter the relationship between these components in males or females.

scholarly journals Potentiation Increases Peak Twitch Torque by Enhancing Rates of Torque Development and Relaxation

2013 ◽  
Vol 38 ◽  
pp. 83-94 ◽  
Author(s):  
Christian Froyd ◽  
Fernando Gabe Beltrami ◽  
Jørgen Jensen ◽  
Timothy David Noakes
Keyword(s):  
Electrical Stimulation ◽  
Maximal Voluntary Contraction ◽  
Femoral Nerve ◽  
Voluntary Contraction ◽  
Physically Active ◽  
Isometric Maximal Voluntary Contraction ◽  
Rate Of Torque Development ◽  
Voluntary Contractions ◽  
Torque Development ◽  
Similar Peak

Abstract The aim of this study was to measure the extent to which potentiation changes in response to an isometric maximal voluntary contraction. Eleven physically active subjects participated in two separate studies. Single stimulus of electrical stimulation of the femoral nerve was used to measure torque at rest in unpotentiated quadriceps muscles (study 1 and 2), and potentiated quadriceps muscles torque in a 10 min period after a 5 s isometric maximal voluntary contraction of the quadriceps muscles (study 1). Additionally, potentiated quadriceps muscles torque was measured every min after a further 10 maximal voluntary contractions repeated every min (study 2). Electrical stimulation repeated several times without previous maximal voluntary contraction showed similar peak twitch torque. Peak twitch torque 4 s after a 5 s maximal voluntary contraction increased by 45±13% (study 1) and by 56±10% (study 2), the rate of torque development by 53±13% and 82±29%, and the rate of relaxation by 50±17% and 59±22%, respectively, but potentiation was lost already two min after a 5 s maximal voluntary contraction. There was a tendency for peak twitch torque to increase for the first five repeated maximal voluntary contractions, suggesting increased potentiation with additional maximal voluntary contractions. Correlations for peak twitch torque vs the rate of torque development and for the rate of relaxation were r2= 0.94 and r2=0.97. The correlation between peak twitch torque, the rate of torque development and the rate of relaxation suggests that potentiation is due to instantaneous changes in skeletal muscle contractility and relaxation.

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.

Wide-pulse-width, high-frequency neuromuscular stimulation: implications for functional electrical stimulation

2006 ◽  
Vol 101 (1) ◽  
pp. 228-240 ◽  
Author(s):  
Evan R. L. Baldwin ◽  
Piotr M. Klakowicz ◽  
David F. Collins
Keyword(s):  
Electrical Stimulation ◽  
Nerve Stimulation ◽  
Maximal Voluntary Contraction ◽  
Neuromuscular Electrical Stimulation ◽  
Initial Step ◽  
Voluntary Contraction ◽  
Triceps Surae ◽  
Muscle Stimulation ◽  
Plantar Flexors ◽  
Wrist Flexors

Electrical stimulation (1-ms pulses, 100 Hz) produces more torque than expected from motor axon activation (extra contractions). This experiment investigates the most effective method of delivering this stimulation for neuromuscular electrical stimulation. Surface stimulation (1-ms pulses; 20 Hz for 2 s, 100 Hz for 2 s, 20 Hz for 3 s) was delivered to triceps surae and wrist flexors (muscle stimulation) and to median and tibial nerves (nerve stimulation) at two intensities. Contractions were evaluated for amplitude, consistency, and stability. Surface electromyograph was collected to assess how H-reflexes and M-waves contribute. In the triceps surae, muscle stimulation produced the largest absolute contractions (23% maximal voluntary contraction), evoked the largest extra contractions as torque increased by 412% after the 100-Hz stimulation, and was more consistent and stable compared with tibial nerve stimulation. Absolute and extra contraction amplitude, consistency, and stability of evoked wrist flexor torques were similar between stimulation types: torques reached 11% maximal voluntary contraction, and extra contractions increased torque by 161%. Extra contractions were 10 times larger in plantar flexors compared with wrist flexors with muscle stimulation but were similar with nerve stimulation. For triceps surae, H reflexes were 3.4 times larger than M waves during nerve stimulation, yet M waves were 15 times larger than H reflexes during muscle stimulation. M waves in the wrist flexors were larger than H reflexes during nerve (8.5 times) and muscle (18.5 times) stimulation. This is an initial step toward utilizing extra contractions for neuromuscular electrical stimulation and the first to demonstrate their presence in the wrist flexors.

scholarly journals 3D curvature of muscle fascicles in triceps surae

2014 ◽  
Vol 117 (11) ◽  
pp. 1388-1397 ◽  
Author(s):  
Manku Rana ◽  
Ghassan Hamarneh ◽  
James M. Wakeling
Keyword(s):  
Mechanical Stability ◽  
Plantar Flexion ◽  
Three Dimensional ◽  
Muscle Length ◽  
3D Ultrasound ◽  
Voluntary Contraction ◽  
Triceps Surae ◽  
Intramuscular Pressure ◽  
2D Ultrasound ◽  
Muscle Fascicles

Muscle fascicles curve along their length, with the curvatures occurring around regions of high intramuscular pressure, and are necessary for mechanical stability. Fascicles are typically considered to lie in fascicle planes that are the planes visualized during dissection or two-dimensional (2D) ultrasound scans. However, it has previously been predicted that fascicles must curve in three-dimensional (3D) and thus the fascicle planes may actually exist as 3D sheets. 3D fascicle curvatures have not been explored in human musculature. Furthermore, if the fascicles do not lie in 2D planes, then this has implications for architectural measures that are derived from 2D ultrasound scans. The purpose of this study was to quantify the 3D curvatures of the muscle fascicles and fascicle sheets within the triceps surae muscles and to test whether these curvatures varied among different contraction levels, muscle length, and regions within the muscle. Six male subjects were tested for three torque levels (0, 30, and 60% maximal voluntary contraction) and four ankle angles (−15, 0, 15, and 30° plantar flexion), and fascicles were imaged using 3D ultrasound techniques. The fascicle curvatures significantly increased at higher ankle torques and shorter muscle lengths. The fascicle sheet curvatures were of similar magnitude to the fascicle curvatures but did not vary between contractions. Fascicle curvatures were regionalized within each muscle with the curvature facing the deeper aponeuroses, and this indicates a greater intramuscular pressure in the deeper layers of muscles. Muscle architectural measures may be in error when using 2D images for complex geometries such as the soleus.

Myogenic and Central Neurogenic Factors in Fatigue in Multiple Sclerosis

1996 ◽  
Vol 1 (4) ◽  
pp. 236-241 ◽  
Author(s):  
M Latash ◽  
E Kalugina ◽  
J Nicholas ◽  
C Orpett ◽  
D Stefoski ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Electrical Stimulation ◽  
Muscular Contraction ◽  
Quadriceps Muscle ◽  
Voluntary Contraction ◽  
Joint Torque ◽  
Subjective Feeling ◽  
Muscle Torque ◽  
Myogenic Factors ◽  
The Right

Short episodes of electrical stimulation were applied to the right quadriceps muscle of patients with multiple sclerosis (MS) and healthy subjects at different times during 60 sec sustained voluntary muscle contractions at 0 to 100% levels of maximal voluntarily generated joint torque. The amplitude of electrically induced increments of torque (ΔT) has been shown to depend upon both the level of muscular contraction and time from the beginning of the contraction. The dependence of ΔT upon the time from the beginning of contraction has been assumed to reflect muscle fatigue. Patients with MS demonstrated an apparent involvement of central neurogenic mechanisms in fatigue manifested as a drop in muscle torque during sustained contractions at 75 and 100% levels when electrical stimulation was able to induce considerable increments in muscle torque. These patients also demonstrated a dependence of ΔT upon the contraction level suggesting that they did not produce maximal voluntary contraction torque in the pre-trial. Fatigue in MS is due to central, neurogenic factors and does not seem to involve any myogenic factors such as might be related to secondary muscle changes due to the long-standing disorder. The subjective feeling of tiredness (‘fatigue’) may be related to a dissociation between central motor commands (‘effort’) and their mechanical consequences.

Difference in aftereffects following prolonged Achilles tendon vibration on muscle activity during maximal voluntary contraction among plantar flexor synergists

2005 ◽  
Vol 98 (4) ◽  
pp. 1427-1433 ◽  
Author(s):  
Junichi Ushiyama ◽  
Kei Masani ◽  
Motoki Kouzaki ◽  
Hiroaki Kanehisa ◽  
Tetsuo Fukunaga
Keyword(s):  
Achilles Tendon ◽  
Muscle Activity ◽  
Maximal Voluntary Contraction ◽  
Plantar Flexion ◽  
Voluntary Contraction ◽  
High Threshold ◽  
Plantar Flexor ◽  
Afferent Activity ◽  
Ia Afferent ◽  
Before And After

It has been suggested that a suppression of maximal voluntary contraction (MVC) induced by prolonged vibration is due to an attenuation of Ia afferent activity. The purpose of the present study was to test the hypothesis that aftereffects following prolonged vibration on muscle activity during MVC differ among plantar flexor synergists owing to a supposed difference in muscle fiber composition. The plantar flexion MVC torque and surface electromyogram (EMG) of the medial head of gastrocnemius (MG), the lateral head of gastrocnemius (LG), and the soleus (Sol) were recorded in 13 subjects before and after prolonged vibration applied to the Achilles tendon at 100 Hz for 30 min. The maximal H reflexes and M waves were also determined from the three muscles, and the ratio between H reflexes and M waves (H/Mmax) was calculated before and after the vibration. The MVC torque was decreased by 16.6 ± 3.7% after the vibration ( P < 0.05; ANOVA). The H/Mmax also decreased for all three muscles, indicating that Ia afferent activity was successfully attenuated by the vibration in all plantar flexors. However, a reduction of EMG during MVC was observed only in MG (12.7 ± 4.0%) and LG (11.4 ± 3.9%) ( P < 0.05; ANOVA), not in Sol (3.4 ± 3.0%). These results demonstrated that prolonged vibration-induced MVC suppression was attributable mainly to the reduction of muscle activity in MG and LG, both of which have a larger proportion of fast-twitch muscle fibers than Sol. This finding suggests that Ia-afferent activity that reinforces the recruitment of high-threshold motor units is necessary to enhance force exertion during MVC.

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