Modeling of Muscle Activation from Electromyography Recordings in Patients with Cerebral Palsy

The present study estimated muscle activation from electromyographic (EMG) recordings in patients with cerebral palsy (CP) during cycling on an ergometer. This could be used as an input to the modeling of muscle force following the neuromusculoskeletal modeling technique which can help to understand the alterations in neuromotor processes underlying disabilities in CP. EMG signals of lower extremity muscle activity from 14 adult patients with CP and 10 adult healthy participants were used here to derive muscle activation. With a self developed EMG system, signals from the following muscles were recorded: Musculus tibialis anterior, Musculus gastrocnemius, Musculus rectus femoris, and Musculus biceps femoris. Collected EMG signals were mathematically transformed into muscle activation following a parameter dependent and a nonlinear transformation. Muscle activation values from patients with CP were compared to equivalent reference values obtained from healthy controls. Muscle activation calculated at specific foot positions deviated clearly from reference values. The deviation was larger for patients with higher degree of spasticity. Observations underline the need of muscle force modeling during cycling for individualized cycling training for rehabilitation strategy.

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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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Lower extremity muscle activation during horizontal and uphill running

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.6.2073 ◽

1997 ◽

Vol 83 (6) ◽

pp. 2073-2079 ◽

Cited By ~ 56

Author(s):

Mark A. Sloniger ◽

Kirk J. Cureton ◽

Barry M. Prior ◽

Ellen M. Evans

Keyword(s):

Lower Extremity ◽

High Intensity ◽

Muscle Activation ◽

Rectus Femoris ◽

Biceps Femoris ◽

Peak Oxygen Uptake ◽

Lower Extremity Muscle ◽

Or Groups ◽

Exercise Induced ◽

The Right

Sloniger, Mark A., Kirk J. Cureton, Barry M. Prior, and Ellen M. Evans. Lower extremity muscle activation during horizontal and uphill running. J. Appl. Physiol. 83(6): 2073–2079, 1997.—To provide more comprehensive information on the extent and pattern of muscle activation during running, we determined lower extremity muscle activation by using exercise-induced contrast shifts in magnetic resonance (MR) images during horizontal and uphill high-intensity (115% of peak oxygen uptake) running to exhaustion (2.0–3.9 min) in 12 young women. The mean percentage of muscle volume activated in the right lower extremity was significantly ( P <0.05) greater during uphill (73 ± 7%) than during horizontal (67 ± 8%) running. The percentage of 13 individual muscles or groups activated varied from 41 to 90% during horizontal running and from 44 to 83% during uphill running. During horizontal running, the muscles or groups most activated were the adductors (90 ± 5%), semitendinosus (86 ± 13%), gracilis (76 ± 20%), biceps femoris (76 ± 12%), and semimembranosus (75 ± 12%). During uphill running, the muscles most activated were the adductors (83 ± 8%), biceps femoris (79 ± 7%), gluteal group (79 ± 11%), gastrocnemius (76 ± 15%), and vastus group (75 ± 13%). Compared with horizontal running, uphill running required considerably greater activation of the vastus group (23%) and soleus (14%) and less activation of the rectus femoris (29%), gracilis (18%), and semitendinosus (17%). We conclude that during high-intensity horizontal and uphill running to exhaustion, lasting 2–3 min, muscles of the lower extremity are not maximally activated, suggesting there is a limit to the extent to which additional muscle mass recruitment can be utilized to meet the demand for force and energy. Greater total muscle activation during exhaustive uphill than during horizontal running is achieved through an altered pattern of muscle activation that involves increased use of some muscles and less use of others.

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Lower-Extremity Muscle Activity During Aquatic and Land Treadmill Running at the Same Speeds

Journal of Sport Rehabilitation ◽

10.1123/jsr.2013-0003 ◽

2014 ◽

Vol 23 (2) ◽

pp. 107-122 ◽

Cited By ~ 5

Author(s):

W. Matthew Silvers ◽

Eadric Bressel ◽

D. Clark Dickin ◽

Garry Killgore ◽

Dennis G. Dolny

Keyword(s):

Lower Extremity ◽

Outcome Measures ◽

Muscle Activity ◽

Tibialis Anterior ◽

Rectus Femoris ◽

Biceps Femoris ◽

Swing Phase ◽

Treadmill Running ◽

Vastus Medialis ◽

Lower Extremity Muscle

Context:Muscle activation during aquatic treadmill (ATM) running has not been examined, despite similar investigations for other modes of aquatic locomotion and increased interest in ATM running.Objectives:The objectives of this study were to compare normalized (percentage of maximal voluntary contraction; %MVC), absolute duration (aDUR), and total (tACT) lower-extremity muscle activity during land treadmill (TM) and ATM running at the same speeds.Design:Exploratory, quasi-experimental, crossover design.Setting:Athletic training facility.Participants:12 healthy recreational runners (age = 25.8 ± 5 y, height = 178.4 ± 8.2 cm, mass = 71.5 ± 11.5 kg, running experience = 8.2 ± 5.3 y) volunteered for participation.Intervention:All participants performed TM and ATM running at 174.4, 201.2, and 228.0 m/min while surface electromyographic data were collected from the vastus medialis, rectus femoris, gastrocnemius, tibialis anterior, and biceps femoris.Main Outcome Measures:For each muscle, a 2 × 3 repeated-measures ANOVA was used to analyze the main effects and environment–speed interaction (P ≤ .05) of each dependent variable: %MVC, aDUR, and tACT.Results:Compared with TM, ATM elicited significantly reduced %MVC (−44.0%) but increased aDUR (+213.1%) and tACT (+41.9%) in the vastus medialis, increased %MVC (+48.7%) and aDUR (+128.1%) in the rectus femoris during swing phase, reduced %MVC (−26.9%) and tACT (−40.1%) in the gastrocnemius, increased aDUR (+33.1%) and tACT (+35.7%) in the tibialis anterior, and increased aDUR (+41.3%) and tACT (+29.2%) in the biceps femoris. At faster running speeds, there were significant increases in tibialis anterior %MVC (+8.6−15.2%) and tACT (+12.7−17.0%) and rectus femoris %MVC (12.1−26.6%; swing phase).Conclusion:No significant environment–speed interaction effects suggested that observed muscle-activity differences between ATM and TM were due to environmental variation, ie, buoyancy (presumed to decrease %MVC) and drag forces (presumed to increase aDUR and tACT) in the water.

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Healthy subjects with lax knees use less knee flexion rather than muscle control to limit anterior tibia translation during landing

Journal of Experimental Orthopaedics ◽

10.1186/s40634-020-00246-6 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Michèle N. J. Keizer ◽

Juha M. Hijmans ◽

Alli Gokeler ◽

Anne Benjaminse ◽

Egbert Otten

Keyword(s):

Knee Flexion ◽

Muscle Activation ◽

Reaction Force ◽

Rectus Femoris ◽

Knee Laxity ◽

Biceps Femoris ◽

Level Of Evidence ◽

Jump Landing ◽

Muscle Activation Patterns ◽

Healthy Participants

Abstract Purpose It has been reported that there is no correlation between anterior tibia translation (ATT) in passive and dynamic situations. Passive ATT (ATTp) may be different to dynamic ATT (ATTd) due to muscle activation patterns. This study aimed to investigate whether muscle activation during jumping can control ATT in healthy participants. Methods ATTp of twenty-one healthy participants was measured using a KT-1000 arthrometer. All participants performed single leg hops for distance during which ATTd, knee flexion angles and knee flexion moments were measured using a 3D motion capture system. During both tests, sEMG signals were recorded. Results A negative correlation was found between ATTp and the maximal ATTd (r = − 0.47, p = 0.028). An N-Way ANOVA showed that larger semitendinosus activity was seen when ATTd was larger, while less biceps femoris activity and rectus femoris activity were seen. Moreover, larger knee extension moment, knee flexion angle and ground reaction force in the anterior-posterior direction were seen when ATTd was larger. Conclusion Participants with more ATTp showed smaller ATTd during jump landing. Muscle activation did not contribute to reduce ATTd during impact of a jump-landing at the observed knee angles. However, subjects with large ATTp landed with less knee flexion and consequently showed less ATTd. The results of this study give information on how healthy people control knee laxity during jump-landing. Level of evidence III

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Muscle Activation in the Main Muscle Groups of the Lower Limbs in High-Level Dancesport Athletes

Medical Problems of Performing Artists ◽

10.21091/mppa.2018.4034 ◽

2018 ◽

Vol 33 (4) ◽

pp. 231-237

Author(s):

Encarnación Liébana ◽

Cristina Monleón ◽

Raquel Morales ◽

Carlos Pablos ◽

Consuelo Moratal ◽

...

Keyword(s):

Tibialis Anterior ◽

Muscle Activation ◽

Rectus Femoris ◽

Biceps Femoris ◽

Lower Limbs ◽

Gastrocnemius Medialis ◽

Leg Muscles ◽

Relative Activation ◽

Muscle Groups ◽

High Level

Dancers are subjected to high-intensity workouts when they practice dancesport, and according to the literature, they are prone to injury, primarily of the lower limbs. The purpose of this study was to determine whether differences exist in relative activation amplitudes for dancers involved in dancesport due to muscle, gender, and type of dance. Measurements were carried out using surface electromyography equipment during the choreography of a performance in the following leg muscles: rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medialis. Eight couples of active dancesport athletes (aged 20.50±2.75 yrs) were analyzed. Significant gender differences were found in rumba in the tibialis anterior (p≤0.05) and gastrocnemius medialis (p≤0.05). Based on the different activations, it is possible to establish possible mechanisms of injury, as well as tools for preventing injuries and improving sports performance.

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A Comparison of the Transient Effect of Complex and Core Stability Exercises on Static Balance Ability and Muscle Activation during Static Standing in Healthy Male Adults

Healthcare ◽

10.3390/healthcare8040375 ◽

2020 ◽

Vol 8 (4) ◽

pp. 375

Author(s):

Ho-Jin Shin ◽

Jin-Hwa Jung ◽

Sung-Hyeon Kim ◽

Suk-Chan Hahm ◽

Hwi-young Cho

Keyword(s):

Path Length ◽

Muscle Activation ◽

Exercise Program ◽

Rectus Femoris ◽

Core Stability ◽

Static Balance ◽

Healthy Male ◽

Lower Extremity Muscle ◽

Significant Difference ◽

Balance Ability

Balance ability is a necessary exercise factor required for the activities of daily living. This study investigated the effects of short-term complex exercise (CE) and core stability exercise (CSE) on balance ability and trunk and lower-extremity muscle activation on healthy male adults. Twenty-nine healthy male adults were included. All performed CE and CSE for 1 min each; the exercise order was randomized. The primary and secondary outcomes were balance ability and muscle activation, respectively. In balance ability, CE showed a significant difference in all variables in both eye-opened and eye-closed conditions compared with the baseline (p < 0.05). In comparisons among exercises, the path length and average velocity variables showed a significant decrease in the eye-opened condition, and the path length variable showed a significant decrease in the eye-closed condition (p < 0.05). In muscle activation, CE showed a significant increase in the gluteus medius (Gmed) and decrease in the rectus femoris (RF), tibialis anterior (TA), and RF/biceps femoris (BF) ratio in the eye-opened condition compared to the baseline and a significant decrease in RF and RF/BF ratio in the eye-closed condition (p < 0.05). Both CE and CSE improved the static balance ability. Furthermore, muscle activation significantly increases in Gmed and decreases in the RF, TA, and RF/BF ratio. Therefore, we recommend including CE in an exercise program that has the purpose of improving static balance ability.

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Effect of Hip Flexion Angle on the Hamstring to Quadriceps Strength Ratio

Sports ◽

10.3390/sports7020043 ◽

2019 ◽

Vol 7 (2) ◽

pp. 43

Author(s):

Eleftherios Kellis ◽

Athanasios Ellinoudis ◽

and Nikolaos Kofotolis

Keyword(s):

Muscle Activation ◽

Rectus Femoris ◽

Biceps Femoris ◽

Knee Extension ◽

Quadriceps Strength ◽

Flexion Angle ◽

Electromyographic Activity ◽

H:Q Ratio ◽

Hip Flexion ◽

Selection Of

The purpose of this study was to compare the hamstring to quadriceps ratio (H:Q) obtained from three different hip flexion angles. Seventy-three young athletes performed maximum isokinetic concentric and eccentric knee extension and flexion efforts at 60 °·s−1 and 240 °·s−1 from hip flexion angles of 90°, 60°, and 120°. The conventional (concentric to concentric), functional (eccentric to concentric) and mixed (eccentric at 30 °·s−1 to concentric torque at 240 °·s−1) H: Q torque ratios and the electromyographic activity from the rectus femoris and biceps femoris were analyzed. The conventional H:Q ratios and the functional H:Q ratios at 60 °·s−1 did not significantly differ between the three testing positions (p > 0.05). In contrast, testing from the 90° hip flexion angle showed a greater functional torque ratio at 240 °·s−1 and a mixed H:Q torque ratio compared with the other two positions (p < 0.05). The hip flexion angle did not influence the recorded muscle activation signals (p > 0.05). For the range of hip flexion angles tested, routine isokinetic assessment of conventional H:Q ratio and functional H:Q ratio at slow speed is not angle-dependent. Should assessment of the functional H:Q ratio at fast angular velocity or the mixed ratio is required, then selection of hip flexion angle is important.

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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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Electromyographic responses to Nordic curl and prone leg curl exercises in football players

Physical Education of Students ◽

10.15561/20755279.2021.0505 ◽

2021 ◽

Vol 25 (5) ◽

pp. 288-298

Author(s):

Murat Çilli ◽

Merve N. Yasar ◽

Onur Çakir

Keyword(s):

Muscle Activity ◽

Muscle Activation ◽

Total Duration ◽

Rectus Femoris ◽

Random Order ◽

Biceps Femoris ◽

Activation Rate ◽

Significant Difference ◽

Activation Rates ◽

Short Time

Background and Study Aim. The aim of this study is to examine the electromyographic responses to Nordic curl and prone leg curl exercises, having two different mechanics. Material and Methods. The athletes performed the prone leg curl and Nordic curl exercises in random order, 6 repetitions each. Electromyographic data of semimemranosus, semitendinosus, biceps femoris and rectus femoris muscles were recorded by 8-channel electromyography in order to examine the muscle responses to exercises. Total duration of exercise, cumulative integrated electromyographic values and muscle activation rates in 5 different intensity zones determined according to MVC% values have been compared. Results. Prone leg curl exercise occurred in less time than Nordic curl exercise. According to the cumulative integrated electromyography data results, all muscles showed similar muscle activation in both exercises. Comparing the muscle activation rates in the five intensity zones, more muscle activity was observed for Nordic curl exercise in the first intensity zone, while prone leg curl exercise was more active in the third and fourth zones. During the prone leg curl exercise, the muscle activation rate of the dominant leg is higher in the first intensity zone, whereas the non-dominant leg in the fourth intensity zone has a higher muscle activation. During the Nordic curl exercise, the muscle activation rates of the dominant leg in the first and fifth intensity zones are higher, whereas the nondominant leg in the fourth intensity zone is higher. Conclusions. Prone leg curl exercises can be preferred in order to stimulate high muscle activation in a short time. Comparing the two exercises there was no significant difference in muscle activity in dominant and nondominant legs.

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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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