The impact of water depth and speed on muscle fiber activation of healthy dogs walking in a water treadmill

Abstract Background Water treadmills are frequently used in the rehabilitation of dogs, for example with the purpose of re-building muscular strength after surgery. However, little is known about how different water depths and velocities affect the muscular workload during aquatic locomotion. This study used acoustic myography to assess hind limb muscle fiber activation in 25 healthy large-breed dogs walking in a water treadmill. Acoustic myography sensors were attached to the skin over the vastus lateralis of the quadriceps and the biceps femoris muscles. The dogs walked at two velocities (30 and 50 m/min) and four water depths: bottom of the pads, hock, stifle and mid-femur. Acoustic myograph signals were analyzed for changes in three muscle function parameters: efficiency/coordination (E-score) and spatial (S-score) and temporal (T-score) summation. Results Differences between E, S, and T were statistically significant compared across different speeds (30, 50) and water levels (0, 1, 2, 3) using a one-way ANOVA with multiple comparisons (Tukey; Geisser-Greenhouse correction) as well as a two-tailed one sample t-test. At 50 m/min in water at the mid-femur, the biceps femoris was less efficient (P < 0.001) and recruited more fibers (P = 0.01) at a higher firing rate (P = 0.03) compared to working in shallower water, while the vastus lateralis was also less efficient (P < 0.01), but spatial and temporal summation did not change significantly. At 30 m/min, biceps efficiency was reduced (P < 0.01) when water was at the mid-femur compared to the bottom of the pads level. Walking in stifle- or hock-deep water did not show increased muscle activation for either muscle compared to walking in water at the bottom of the pads. Conclusion More muscle activation was required to walk in water at a depth at the level of the mid-femur compared to shallower water, and this exercise was more demanding for the biceps femoris, a muscle engaged in propulsion, than for vastus lateralis. These findings may help practitioners towards making more precise rehabilitation protocols.

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Muscle Coactivation Before and After the Impact Phase of Running Following Isokinetic Fatigue

Journal of Athletic Training ◽

10.4085/1062-6050-46.1.11 ◽

2011 ◽

Vol 46 (1) ◽

pp. 11-19 ◽

Cited By ~ 19

Author(s):

Eleftherios Kellis ◽

Andreas Zafeiridis ◽

Ioannis G. Amiridis

Keyword(s):

Muscle Activation ◽

Biceps Femoris ◽

Knee Extension ◽

Knee Extensors ◽

Training Experience ◽

Cross Sectional ◽

Muscle Activation Patterns ◽

Strength Capacity ◽

Before And After ◽

The Impact

Abstract Context: The effects of fatigue on impact loading during running are unclear, with some authors reporting increased impact forces and others reporting decreased forces. Objective: To examine the effects of isokinetic fatigue on muscle cocontraction ratios about the knee and ankle during running. Design: Cross-sectional study. Setting: Neuromechanics laboratory. Patients or Other Participants: Female middle-distance runners (age = 21.3 ± 1.93 years) with at least 5 years of training experience. Intervention(s): Participants ran on the treadmill at 3.61 m/s before and immediately after the fatigue protocol, which consisted of consecutive, concentric knee extension-flexion at 120°/s until they could no longer produce 30% of the maximum knee-extension moment achieved in the familiarization session for 3 consecutive repetitions. Main Outcome Measure(s): Electromyographic (EMG) amplitude of the vastus medialis (VM), biceps femoris (BF), gastrocnemius (GAS), and tibialis anterior (TA) was recorded using surface electrodes. Agonist∶antagonist EMG ratios for the knee (VM∶BF) and ankle (GAS∶TA) were calculated for the preactivation (PR), initial loading response (LR1), and late loading response (LR2) phases of running. Hip-, knee-, and ankle-joint angular displacements at initial foot contact were obtained from 3-dimensional kinematic tracings. Results: Fatigue did not alter the VM∶BF EMG ratio during the PR phase (P > .05), but it increased the ratio during the LR1 phase (P < .05). The GAS∶TA EMG ratio increased during the LR1 phase after fatigue (P < .05) but remained unchanged during the PR and LR2 phrases (P > .05). Conclusions: The increased agonist EMG activation, coupled with reduced antagonist EMG activation after impact, indicates that the acute decrease in muscle strength capacity of the knee extensors and flexors results in altered muscle-activation patterns about the knee and ankle before and after foot impact.

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Effects of Short-Term Training With Uncoupled Cranks in Trained Cyclists

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.7.2.113 ◽

2012 ◽

Vol 7 (2) ◽

pp. 113-120 ◽

Cited By ~ 1

Author(s):

Jack M. Burns ◽

Jeremiah J. Peiffer ◽

Chris R. Abbiss ◽

Greig Watson ◽

Angus Burnett ◽

...

Keyword(s):

Muscle Activation ◽

Vastus Lateralis ◽

Biceps Femoris ◽

Training Group ◽

Recovery Phase ◽

Muscle Recruitment ◽

Short Term ◽

Activation Patterns ◽

Gross Efficiency ◽

Muscle Activation Patterns

Purpose:Manufacturers of uncoupled cycling cranks claim that their use will increase economy of motion and gross efficiency. Purportedly, this occurs by altering the muscle-recruitment patterns contributing to the resistive forces occurring during the recovery phase of the pedal stroke. Uncoupled cranks use an independent-clutch design by which each leg cycles independently of the other (ie, the cranks are not fixed together). However, research examining the efficacy of training with uncoupled cranks is equivocal. The purpose of this study was to determine the effect of short-term training with uncoupled cranks on the performance-related variables economy of motion, gross efficiency, maximal oxygen uptake (VO2max), and muscle-activation patterns.Methods:Sixteen trained cyclists were matched-paired into either an uncoupled-crank or a normal-crank training group. Both groups performed 5 wk of training on their assigned cranks. Before and after training, participants completed a graded exercise test using normal cranks. Expired gases were collected to determine economy of motion, gross efficiency, and VO2max, while integrated electromyography (iEMG) was used to examine muscle-activation patterns of the vastus lateralis, biceps femoris, and gastrocnemius.Results:No significant changes between groups were observed for economy of motion, gross efficiency, VO2max, or iEMG in the uncoupled- or normal-crank group.Conclusions:Five weeks of training with uncoupled cycling cranks had no effect on economy of motion, gross efficiency, muscle recruitment, or VO2max compared with training on normal cranks.

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Quadriceps and hamstrings coactivation in exercises used in prevention and rehabilitation of hamstring strain injury in young soccer players

10.1101/574210 ◽

2019 ◽

Author(s):

Gonzalo Torres ◽

David Chorro ◽

Archit Navandar ◽

Javier Rueda ◽

Luís Fernández ◽

...

Keyword(s):

Muscle Activation ◽

Vastus Lateralis ◽

Rectus Femoris ◽

Biceps Femoris ◽

Activation Pattern ◽

Male Youth ◽

Maximum Voluntary Isometric Contraction ◽

Hamstring Strain ◽

Exercise Muscle ◽

Injury Recovery

AbstractThis study aimed to study the co-activation of hamstring-quadriceps muscles during submaximal strength exercises without the use of maximum voluntary isometric contraction testing and compare (i) the inter-limb differences in muscle activation, (ii) the intra-muscular group activation pattern, and (iii) the activation during different phases of the exercise. Muscle activation was recorded by surface electromyography of 19 elite male youth players. Participants performed five repetitions of the Bulgarian squat, lunge and the squat with an external load of 10 kg. Electrical activity was recorded for the rectus femoris, vastus medialis, vastus lateralis, biceps femoris and semitendinosus. No significant inter-limb differences were found (F1, 13=619; p=0.82; partial η2=0.045). Significant differences were found in the muscle activation between different muscles within the muscle group (quadriceps and hamstrings) for each of the exercises: Bulgarian squat (F1,18=331: p<0.001; partial η2=0.80), lunge (F4,72=114.5; p<0.001; partial η2=0.86) and squat (F1,16=247.31; p<0.001; partial η2=0.93).Differences were found between the concentric, isometric and eccentric phases of each of the exercises (F2, 26=52.27; p=0.02; partial η2=0.80). The existence of an activation pattern of each of the muscles in the three proposed exercises could be used for muscle assessment and as a tool for injury recovery.

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Characterization of kinesiological patterns of the frontal kick, mae-geri, in karate experts and non-karate practitioners

Revista de Artes Marciales Asiáticas ◽

10.18002/rama.v9i1.1163 ◽

2014 ◽

Vol 9 (1) ◽

pp. 20 ◽

Cited By ~ 3

Author(s):

António M. VencesBrito ◽

Marco A. Colaço Branco ◽

Renato M. Cordeiro Fernandes ◽

Mário A. Rodrigues Ferreira ◽

Orlando J. S. M. Fernandes ◽

...

Keyword(s):

Muscle Activity ◽

Vastus Lateralis ◽

Plantar Flexion ◽

Neuromuscular Control ◽

Rectus Femoris ◽

Biceps Femoris ◽

Knee Extension ◽

Maximum Speed ◽

Ballistic Performance ◽

The Impact

Presently, coaches and researchers need to have a better comprehension of the kinesiological parameters that should be an important tool to support teaching methodologies and to improve skills performance in sports. The aim of this study was to (i) identify the kinematic and neuromuscular control patterns of the front kick (mae-geri) to a fixed target performed by 14 experienced karate practitioners, and (ii) compare it with the execution of 16 participants without any karate experience, allowing the use of those references in the analysis of the training and learning process. Results showed that the kinematic and neuromuscular activity during the kick performance occurs within 600 ms. Muscle activity and kinematic analysis demonstrated a sequence of activation bracing a proximal-to-distal direction, with the muscles presenting two distinct periods of activity (1, 2), where the karateka group has a greater intensity of activation – root mean square (RMS) and electromyography (EMG) peak – in the first period on Rectus Femoris (RF1) and Vastus Lateralis (VL1) and a lower duration of co-contraction in both periods on Rectus Femoris-Biceps Femoris and Vastus Lateralis-Biceps Femoris (RF-BF; VL-BF). In the skill performance, the hip flexion, the knee extension and the ankle plantar flexion movements were executed with smaller difference in the range of action (ROA) in the karateka group, reflecting different positions of the segments. In conclusion, it was observed a general kinesiological pattern, which was similar in karateka and non-karateka practitioners. However, in the karateka group, the training induces a specialization in the muscle activity reflected in EMG and kinematic data, which leads to a better ballistic performance in the execution of the mae-geri kick, associated with a maximum speed of the distal segments, reached closer to the impact moment, possibly representing more power in the contact.

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TRAINING LOAD DEMANDS MEASURED BY SURFACE ELECTROMYOGRAPHY WEARABLE TECHNOLOGY WHEN PERFORMING LAW ENFORCEMENT-SPECIFIC BODY DRAGS

Facta Universitatis Series Physical Education and Sport ◽

10.22190/fupes200221002l ◽

2020 ◽

pp. 001

Author(s):

Robert George Lockie ◽

Ashley Bloodgood ◽

Matthew Moreno ◽

Megan McGuire ◽

Katherine Balfany ◽

...

Keyword(s):

Law Enforcement ◽

Surface Electromyography ◽

Muscle Activation ◽

Vastus Lateralis ◽

Gluteus Maximus ◽

Biceps Femoris ◽

Wearable Technology ◽

Training Load ◽

Semg Signal ◽

Body Drag

The use of surface electromyography (sEMG) wearable technology to measure training load (TL) during law enforcement-specific tasks (e.g. a body drag) requires investigation. This study determined muscle activation differences represented as TL during a 9.75-m drag with 74.84 kg and 90.72 kg dummies. Eight men and three women were fitted with a compression short or legging embedded with sEMG wearable technology to measure the quadriceps (QUAD; vastus medialis+vastus lateralis), biceps femoris (BF), and gluteus maximus (GM). After fitting on day one, participants completed maximal voluntary isometric contractions for each muscle to normalize the sEMG signal and calculate TL units. On days two and three, participants performed a 9.75 m body drag using either the 74.84 kg or the 90.72 kg dummy while wearing the technology. Participants lifted the dummy off the floor to a standing position and dragged it as quickly as possible over 9.75 m. Paired samples t-tests calculated between-drag differences for: time; QUAD, BF, GM, and total TL; and QUAD-BF, GM-BF, anterior-posterior (QUAD-GM+BF) ratios. QUAD TL was 9% greater (p=0.035), and GM TL was 8% lower (p=0.043), in the 90.72 kg body drag compared to the 74.84 kg drag. There were no between-mass differences in time, BF TL, total TL, or the ratios. QUAD TL increased while GM TL decreased when participants dragged a 90.72 kg dummy. As drag time was not different between the masses, drag mechanics may have changed leading to increased QUAD TL. sEMG wearable technology could be a useful method to measure TL in law enforcement-specific dragging tasks.

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Evaluation of the Lower Limb Muscles’ Electromyographic Activity during the Leg Press Exercise and Its Variants: A Systematic Review

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17134626 ◽

2020 ◽

Vol 17 (13) ◽

pp. 4626

Author(s):

Isabel Martín-Fuentes ◽

José M. Oliva-Lozano ◽

José M. Muyor

Keyword(s):

Muscle Activation ◽

Vastus Lateralis ◽

Muscular Activity ◽

Rectus Femoris ◽

Biceps Femoris ◽

Quadriceps Muscle ◽

Electromyographic Activity ◽

Full Extension ◽

Cross Sectional ◽

Leg Press

The aim of this study was to analyze the literature on muscle activation measured by surface electromyography (sEMG) of the muscles recruited when performing the leg press exercise and its variants. The Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to report this review. The search was carried out using the PubMed, Scopus, and Web of Science electronic databases. The articles selected met the following inclusion criteria: (a) a cross-sectional or longitudinal study design; (b) neuromuscular activation assessed during the leg press exercise, or its variants; (c) muscle activation data collected using sEMG; and (d) study samples comprising healthy and trained participants. The main findings indicate that the leg press exercise elicited the greatest sEMG activity from the quadriceps muscle complex, which was shown to be greater as the knee flexion angle increased. In conclusion, (1) the vastus lateralis and vastus medialis elicited the greatest muscle activation during the leg press exercise, followed closely by the rectus femoris; (2) the biceps femoris and the gastrocnemius medialis showed greater muscular activity as the knee reached full extension, whereas the vastus lateralis and medialis, the rectus femoris, and the tibialis anterior showed a decreasing muscular activity pattern as the knee reached full extension; (3) evidence on the influence of kinematics modifications over sEMG during leg press variants is still not compelling as very few studies match their findings.

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Altering muscle activity in the lower extremities by bipedal landing with different drop tasks and shoes

Isokinetics and Exercise Science ◽

10.3233/ies-210212 ◽

2021 ◽

pp. 1-11

Author(s):

Yang Yang ◽

Changxiao Yu ◽

Chenhao Yang ◽

Liqin Deng ◽

Weijie Fu

Keyword(s):

Lower Extremity ◽

Muscle Activation ◽

Vastus Lateralis ◽

Movement Control ◽

Rectus Femoris ◽

Biceps Femoris ◽

The Body ◽

Basketball Players ◽

Lower Extremity Muscle ◽

Body Tissues

BACKGROUND: The ability of the lower-extremity muscle activation directly affects the performance and in turn interacts with the loading conditions of the muscle itself. However, systematic information concerning the characteristics of lower-extremity muscle during landings is lacking. In particular, the landing height and shoes are also important factors based on the actual situation, which could further contribute to understanding the neuromuscular activity and how biochemical response of the body tissues to double-leg drop landings. OBJECTIVE: The study was to investigate the effects of landing tasks on the activation of lower-extremity muscles and explore the relationship among movement control, landing heights, shoe cushioning, and muscle activities. METHODS: Twelve male basketball players were recruited to perform drop jump (DJ) and passive landing (PL) from three heights (30, 45, and 60 cm) while wearing highly-cushioned basketball shoes (HC) and less-cushioned control shoes (LC). EMG electrodes were used to record the activities of the target muscles (rectus femoris, vastus lateralis, biceps femoris, tibialis anterior, and lateral gastrocnemius) during the landing tasks. RESULTS: Pre- and post-activation activity of the lower-extremity muscles significantly decreased during PL compared with those during DJ (p< 0.05). No significant shoe effects on the characteristics of muscle activation and coactivation during DJ movements were observed. However, the participants wearing LC showed significantly higher muscle post-activation (p< 0.05) at the three drop heights during PL compared with those wearing HC. Coactivation of the ankle muscles was higher in LC than in HC during 30-cm PL (p< 0.05). CONCLUSIONS: The activation patterns of lower-extremity muscles can be significantly influenced by landing types. Highly-cushioned basketball shoes would help reduce the risk of injuries by appropriately tuning the muscles during the PL.

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An Anthropometrically Parameterized Assistive Lower-limb Exoskeleton

Journal of Biomechanical Engineering ◽

10.1115/1.4051214 ◽

2021 ◽

Author(s):

Curt Laubscher ◽

Ryan Farris ◽

Antonie van den Bogert ◽

Jerzy T. Sawicki

Keyword(s):

Lower Limb ◽

Muscle Activation ◽

Vastus Lateralis ◽

Mechanical Energy ◽

Biceps Femoris ◽

Knee Joints ◽

Lower Limb Exoskeleton ◽

Hip Abduction ◽

The Subject ◽

Muscle Activations

Abstract This paper presents a newly developed lower-limb exoskeleton tested for walking assistance. The novel exoskeleton design methodology uses additive manufacturing and a parametrized model based on user anthropometrics to give a person-specific custom fit. The process is applied to average children and a healthy adult, and a prototype device is fabricated for the adult to validate the feasibility of the approach. The developed prototype actuates the hip and knee joints without restricting hip abduction-adduction motion. To test usability of the device and evaluate walking assistance, user torque, mechanical energy generated, and muscle activation are analyzed in an assisted condition where the subject walks on a level treadmill with the exoskeleton powered. This is compared to an unassisted condition with the exoskeleton unpowered and a baseline condition with the subject not wearing the exoskeleton. Comparing assisted to baseline conditions, torque magnitudes increased at the hip and knee, mechanical energy generated increased at the hip but decreased at the knee, and muscle activations decreased in the Biceps Femoris and increased in the Vastus Lateralis. The presented preliminary results are inconclusive on whether the newly developed exoskeleton can assist in walking though show promise for basic usability of the device.

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Electromyographic evaluation of the lower limbs of patients with Down syndrome in hippotherapy

Acta Scientiarum Health Sciences ◽

10.4025/actascihealthsci.v39i1.28868 ◽

2017 ◽

Vol 39 (1) ◽

pp. 17 ◽

Cited By ~ 3

Author(s):

Mariane Fernandes Ribeiro ◽

Ana Paula Espindula ◽

Alex Abadio Ferreira ◽

Luciane Aparecida Pascucci Sande de Souza ◽

Vicente De Paula Antunes Teixeira

Keyword(s):

Down Syndrome ◽

Muscle Activation ◽

Motor Behavior ◽

Vastus Lateralis ◽

Rectus Femoris ◽

Gluteus Medius ◽

Biceps Femoris ◽

Functional Results ◽

Lower Limbs ◽

Tensor Fasciae Latae

Hippotherapy is a therapeutic method that uses the horse’s movement to achieve functional results in practitioners with Down syndrome (DS), who present motor and neurophysiological changes that affect the musculoskeletal system. Evaluating the motor behavior related to the control and the improvement of muscle activation in practitioners with Down syndrome subjected to hippotherapy. 10 practitioners were divided into two groups: Down Group (DG) – practitioners with DS, and Healthy Group (HG) – practitioners with no physical impairment. The muscles gluteus medius, tensor fasciae latae, rectus femoris, vastus medialis, vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius were evaluated by electromyography using gross RMS values, which correspond to muscle activation; the evaluations were performed on the 1st and 10th hippotherapy sessions (frequency: once a week), and after 2 months interval without treatment, they were performed on the 1st and 10th hippotherapy sessions (frequency: twice a week). It was noted that activation of the studied muscles increased with the passing of sessions, regardless the weekly frequency of attendance; however, the period without treatment resulted in reduction of this effect. Practitioners with DS presented satisfactory changes in muscle activation pattern, in learning and in motor behavior during hippotherapy sessions.

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Activation of Antagonist Knee Muscles during Isokinetic Efforts in Prepubertal and Adult Males

Pediatric Exercise Science ◽

10.1123/pes.17.2.171 ◽

2005 ◽

Vol 17 (2) ◽

pp. 171-181 ◽

Cited By ~ 7

Author(s):

Eleni Bassa ◽

Dimitrios Patikas ◽

Christos Kotzamanidis

Keyword(s):

Muscle Activation ◽

Vastus Lateralis ◽

Force Production ◽

Biceps Femoris ◽

Antagonistic Activity ◽

Adult Males ◽

Significant Difference ◽

Angular Velocities ◽

Knee Muscle ◽

Muscle Force Production

The deficit of muscle-force production observed in children can be partly attributed to neural factors, such as an increased level of coactivation. This hypothesis, however, has not been thoroughly investigated under concentric and eccentric isokinetic conditions at different angular velocities. Thus, the purpose of this study was to examine whether prepubescent children present higher levels of activation of the antagonist knee muscles during isokinetic, concentric, and eccentric knee efforts compared with adults. Eighteen prepubertal and 13 young adult males (age: 10.9 ± 0.5 and 18.1 ± 0.1 years, respectively) performed maximal concentric and eccentric knee extensions and flexions at 45, 90, and 180 degrees/s. The vastus lateralis and biceps femoris electromyogram was recorded and the antagonist activation (coactivation) was calculated. Concentric contractions for both groups revealed significantly higher coactivation values (p < .05) compared with the eccentric conditions. Furthermore, increasing the angular velocity increased the level of coactivation significantly only during the concentric efforts for both groups. No significant difference in the antagonistic activity of the vastus lateralis and biceps femoris, however, was found between groups. Therefore, increased antagonist knee-muscle activation, which enhances joint stabilization during isokinetic concentric and eccentric effort, is similar in both prepubescent and adult males.

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