The Effect of Fatigue on Leg Muscle Activation and Tibial Acceleration During a Jumping Task

2020 ◽  
Vol 29 (8) ◽  
pp. 1093-1099
Author(s):  
Michelle A. Sandrey ◽  
Yu-Jen Chang ◽  
Jean L. McCrory
Keyword(s):  
Lower Extremity ◽  
Athletic Training ◽  
Repeated Measures ◽  
Tibialis Anterior ◽  
Muscle Activation ◽  
Vertical Jump ◽  
Medial Gastrocnemius ◽  
History Of ◽  
Linear Envelope ◽  
And Control

Context: Lower-extremity stress fractures (SFx) are a common occurrence during load-bearing activities of jumping and landing. To detect biomechanical changes during jumping postinjury, a fatigue model could be used. Objective: To evaluate muscle activation in the lower leg and tibial accelerations (TAs) prefatigue to postfatigue following a jumping task in those with and without a history of SFx. Design: Repeated-measures. Setting: Athletic Training Research Lab. Participants: A total of 30 active college-aged students with and without a history of lower-extremity (leg or foot) SFx (15 males and 15 females; 21.5 [5.04] y, height = 173.5 [12.7] cm, weight = 72.65 [16.4] kg). Intervention: A maximal vertical jump on one leg 3 times with arms folded across the chest prefatigue to postfatigue was performed. Fatigue protocol was standing heel raises on a custom-built platform at a pace controlled by a metronome until task failure was reached. Legs were tested using a randomized testing order. Electromyographic (EMG) surface electrodes were placed on the medial gastrocnemius, soleus, and tibialis anterior following a standardized placement protocol. A triaxial accelerometer was attached to the proximal anteromedial surface of the tibia. Main Outcome Measures: Linear envelopes of the medial gastrocnemius, soleus, and tibialis anterior and peak accelerations (resultant acceleration takeoff and landing). Results: Significant interaction for leg × test for tibialis anterior with a posttest difference between SFx and control (P = .05). There were decreases in EMG linear envelope following fatigue for medial gastrocnemius (P < .01) and tibialis anterior (P = .12) pretest to posttest. At takeoff, TA was greater in the SFx contralateral leg in comparison with the control leg (P = .04). At landing, TA was greater in posttest (P < .01) and in the SFx leg compared with SFx contralateral (P = .14). Conclusion: A decrease in muscle activity and an increase in TA following fatigue were noted for all subjects but especially for those with a history of SFx.

scholarly journals Role of Occupational Footwear and Prolonged Walking on Lower Extremity Muscle Activation during Maximal Exertions and Postural Stability Tasks

Biomechanics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 202-213
Author(s):  
Harish Chander ◽  
Sachini N. K. Kodithuwakku Arachchige ◽  
Alana J. Turner ◽  
Reuben F. Burch V ◽  
Adam C. Knight ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Muscle Activity ◽  
Repeated Measures ◽  
Postural Stability ◽  
Muscle Activation ◽  
Medial Gastrocnemius ◽  
Lower Extremity Muscle ◽  
Prolonged Duration ◽  
The Mean ◽  
The Impact

Background: Occupational footwear and a prolonged duration of walking have been previously reported to play a role in maintaining postural stability. The purpose of this paper was to analyze the impact of three types of occupational footwear: the steel-toed work boot (ST), the tactical work boot (TB), and the low-top work shoe (LT) on previously unreported lower extremity muscle activity during postural stability tasks. Methods: Electromyography (EMG) muscle activity was measured from four lower extremity muscles (vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) during maximal voluntary isometric contractions (MVIC) and during a sensory organization test (SOT) every 30 min over a 4 h simulated workload while wearing ST, TB, and LT footwear. The mean MVIC and the mean and percentage MVIC during each SOT condition from each muscle was analyzed individually using a repeated measures ANOVA at an alpha level of 0.05. Results: Significant differences (p < 0.05) were found for maximal exertions, but this was limited to only the time main effect. No significant differences existed for EMG measures during the SOT. Conclusion: The findings suggest that occupational footwear type does not influence lower extremity muscle activity during both MVIC and SOT. Significantly lower muscle activity during maximal exertions over the course of the 4 h workload was evident, which can be attributed to localized muscular fatigue, but this was not sufficient to impact muscle activity during postural stability tasks.

Influence of Ankle Injury on Muscle Activation and Postural Control During Ballet Grand Plié

2014 ◽  
Vol 30 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Chia-Wei Lin ◽  
Fong-Chin Su ◽  
Cheng-Feng Lin
Keyword(s):  
Lower Extremity ◽  
Tibialis Anterior ◽  
Muscle Activation ◽  
Center Of Pressure ◽  
Ankle Injury ◽  
Medial Gastrocnemius ◽  
Ankle Sprains ◽  
Activation Patterns ◽  
Temporal Muscle ◽  
Muscle Activation Patterns

Ballet deep squat with legs rotated externally (grand plié) is a fundamental movement for dancers. However, performing this task is a challenge to ankle control, particularly for those with ankle injury. Thus, the purpose of this study was to investigate how ankle sprains affect the ability of postural and muscular control during grand plié in ballet dancers. Thirteen injured dancers and 20 uninjured dancers performed a 15 second grand plié consisting of lowering, squatting, and rising phases. The lower extremity motion patterns and muscle activities, pelvic orientation, and center of pressure (COP) excursion were measured. In addition, a principal component analysis was applied to analyze waveforms of muscle activity in bilateral medial gastrocnemius, peroneus longus, and tibialis anterior. Our findings showed that the injured dancers had smaller pelvic motions and COP excursions, greater maximum angles of knee flexion and ankle dorsiflexion as well as different temporal activation patterns of the medial gastrocnemius and tibialis anterior. These findings suggested that the injured dancers coped with postural challenges by changing lower extremity motions and temporal muscle activation patterns.

scholarly journals Cooling of Lower Extremity Muscles According to Subcutaneous Tissue Thickness

2019 ◽  
Vol 54 (12) ◽  
pp. 1304-1307 ◽  
Author(s):  
Noelle M. Selkow
Keyword(s):  
Lower Extremity ◽  
Athletic Training ◽  
Treatment Time ◽  
Subcutaneous Tissue ◽  
Rectus Femoris ◽  
Treatment Temperature ◽  
Medial Gastrocnemius ◽  
Tissue Thickness ◽  
End Of Treatment ◽  
Standardized Treatment

Context When using an ice bag, previous researchers recommended cooling times based on the amount of subcutaneous tissue. Unfortunately, many clinicians are unaware of these recommendations or whether they can be applied to other muscles. Objective To examine if muscles of the lower extremity cool similarly based on recommended cooling times. Design Crossover study. Setting Athletic training laboratory. Patients or Other Participants Fourteen healthy participants volunteered (8 men, 6 women; age = 21.1 ± 2.2 years, height = 174.2 ± 4.5 cm, weight = 74.0 ± 7.5 kg). Intervention(s) Subcutaneous tissue thickness was measured at the largest girth of the thigh, medial gastrocnemius, and medial hamstring. Participants were randomized to have either the rectus femoris or medial gastrocnemius and medial hamstring tested first. Using sterile techniques, the examiner inserted a thermocouple 1 cm into the muscle after accounting for subcutaneous tissue thickness. After the temperature stabilized, a 750-g ice bag was applied for 10 to 60 minutes to the area(s) for the recommended length of time based on subcutaneous adipose thickness (0 to 5 mm [10 minutes]; 5.5 to 10 mm (25 minutes]; 10.5 to 15 mm [40 minutes]; 15.5 to 20 mm [60 minutes)]. After the ice bag was removed, temperature was monitored for 30 minutes. At least 1 week later, each participant returned to complete testing of the other muscle(s). Main Outcome Measure(s) Intramuscular temperature (°C) at baseline, end of treatment time (0 minutes), and posttreatment recovery (10, 20, and 30 minutes postintervention). Results At the end of treatment, temperature did not differ by subcutaneous tissue thickness (10 minutes = 29.0°C ± 3.8°C, 25 minutes = 28.7°C ± 3.2°C, 40 minutes = 28.7°C ± 6.0°C, 60 minutes = 30.0°C ± 2.9°C) or muscle (rectus femoris = 30.1°C ± 3.8°C, gastrocnemius = 28.6°C ± 5.4°C, hamstrings = 28.1°C ± 2.5°C). No significant interaction was present for subcutaneous tissue thickness or muscle (P ≥ .126). Conclusions Lower extremity muscles seemed to cool similarly based on the recommended cooling times for subcutaneous tissue thickness. Clinicians should move away from standardized treatment times and adjust the amount of cooling time by ice-bag application based on subcutaneous tissue thickness.

scholarly journals Repeated Menthol Mouth Swilling Affects Neither Strength nor Power Performance

Sports ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 90 ◽  
Author(s):  
Russ Best ◽  
Dani Temm ◽  
Holly Hucker ◽  
Kerin McDonald
Keyword(s):  
Repeated Measures ◽  
Vertical Jump ◽  
Average Power ◽  
Small Degree ◽  
Power Performance ◽  
Mean Power ◽  
Experimental Conditions ◽  
Jump Performance ◽  
Experimental Trials ◽  
And Control

This study aimed to assess the effects of repeated menthol mouth swilling upon strength and power performance. Nineteen (10 male) participants completed familiarisation and experimental trials of repeated menthol mouth swilling (0.1% concentration) or control (no swill) in a randomised crossover design. Participants performed an isometric mid-thigh pull (IMTP; peak and mean force; N), vertical jump (peak; cm) and six second sprint (peak and mean power; W) under each condition. Participants completed three efforts per exercise task interspersed with three-minute recoveries. Mean best values were analysed via a two-way mixed repeated measures ANOVA, and differences reported as effect sizes ± 95% confidence intervals, with accompanying descriptors and p values. Differences in peak IMTP values were unclear between familiarisation and experimental trials, and between menthol and control conditions. Mean IMTP force differed between familiarisation and control (0.51; −0.15 to 1.14; p = 0.001) and familiarisation and menthol conditions (0.50; −0.15 to 1.14; p = 0.002) by a small degree, but were unclear between control and menthol conditions. Unclear differences were also noted on vertical jump performance compared to familiarisation and between experimental conditions, with repeated six second peak and average power performance also showing unclear effects across all comparisons. We conclude that repeated menthol mouth swilling does not improve strength or power performance.

scholarly journals Quantifying Topographical Changes in Muscle Activation: A Statistical Parametric Mapping Approach

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 71
Author(s):  
Patricio A. Pincheira ◽  
Eduardo Martinez-Valdes ◽  
Carlos De la Fuente ◽  
Felipe Palma ◽  
Oscar Valencia ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Muscle Activation ◽  
Plantar Flexion ◽  
Statistical Parametric Mapping ◽  
High Sensitivity ◽  
Voluntary Contraction ◽  
Medial Gastrocnemius ◽  
Isometric Contractions ◽  
Parametric Mapping ◽  
Repeated Measures Anova

Regional changes in muscle activation occur at different contraction intensities. These changes can be observed with activity maps created with high-density electromyography (HDEMG). When quantifying these changes, statistical parametric mapping (SPM) is a neuroimaging technique that may be used to perform statistical analyses with high sensitivity and spatial resolution. The aim of this study was to identify regional changes in muscle activation at different contraction intensities, comparing SPM and the HDEMG barycenter (centroid). Twelve participants performed plantar flexion isometric contractions at 20%, 40%, and 60% of the maximal voluntary contraction (MVC), while HDEMG was recorded from the medial gastrocnemius. An SPM repeated measures ANOVA design revealed specific mediolateral and cephalocaudal changes in muscle activation with increasing contraction intensities, which were not clearly detected by the variation in the barycenter coordinates. Only SPM revealed statistically significant nonuniform changes in EMG amplitude between all increasing levels of muscle activation.

Hip-Abduction Torque and Muscle Activation in People With Low Back Pain

2015 ◽  
Vol 24 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Mark A. Sutherlin ◽  
Joseph M. Hart
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Muscle Function ◽  
Muscle Activation ◽  
Low Back ◽  
Hip Muscle ◽  
Hip Abduction ◽  
History Of

Context:Individuals with a history of low back pain (LBP) may present with decreased hip-abduction strength and increased trunk or gluteus maximus (GMax) fatigability. However, the effect of hip-abduction exercise on hip-muscle function has not been previously reported.Objective:To compare hip-abduction torque and muscle activation of the hip, thigh, and trunk between individuals with and without a history of LBP during repeated bouts of side-lying hip-abduction exercise.Design:Repeated measures.Setting:Clinical laboratory.Participants:12 individuals with a history of LBP and 12 controls.Intervention:Repeated 30-s hip-abduction contractions.Main Outcome Measures:Hip-abduction torque, normalized root-mean-squared (RMS) muscle activation, percent RMS muscle activation, and forward general linear regression.Results:Hip-abduction torque reduced in all participants as a result of exercise (1.57 ± 0.36 Nm/kg, 1.12 ± 0.36 Nm/kg; P < .001), but there were no group differences (F = 0.129, P = .723) or group-by-time interactions (F = 1.098, P = .358). All participants had increased GMax activation during the first bout of exercise (0.96 ± 1.00, 1.18 ± 1.03; P = .038). Individuals with a history of LBP had significantly greater GMax activation at multiple points during repeated exercise (P < .05) and a significantly lower percent of muscle activation for the GMax (P = .050) at the start of the third bout of exercise and for the biceps femoris (P = .039) at the end of exercise. The gluteal muscles best predicted hip-abduction torque in controls, while no consistent muscles were identified for individuals with a history of LBP.Conclusions:Hip-abduction torque decreased in all individuals after hip-abduction exercise, although individuals with a history of LBP had increased GMax activation during exercise. Gluteal muscle activity explained hip-abduction torque in healthy individuals but not in those with a history of LBP. Alterations in hip-muscle function may exist in individuals with a history of LBP.

Landing Constraints Influence Ground Reaction Forces and Lower Extremity EMG in Female Volleyball Players

2004 ◽  
Vol 20 (1) ◽  
pp. 38-50 ◽  
Author(s):  
Mark D. Tillman ◽  
Rachel M. Criss ◽  
Denis Brunt ◽  
Chris J. Hass
Keyword(s):  
Muscle Activity ◽  
Repeated Measures ◽  
Muscle Activation ◽  
Vertical Jump ◽  
Lateral Loading ◽  
Initial Contact ◽  
Ground Reaction Forces ◽  
Vertical Loading ◽  
Volleyball Players ◽  
Reaction Forces

The purposes of this study were to analyze double-limb, dominant-limb, and nondominant-limb landings, each with a two-footed takeoff, in order to detect potential differences in muscle activity and ground reaction forces and to examine the possible influence of leg dominance on these parameters. Each of the three jump landing combinations was analyzed in 11 healthy female volleyball players (age 21 ± 3 yrs; height 171 ± 5 cm, mass 61.6 ± 5.5 kg, max. vertical jump height 28 ± 4 cm). Ground reaction forces under each limb and bilateral muscle activity of the vastus medialis, hamstrings, and lateral gastrocnemius muscles were synchronized and collected at 1,000 Hz. Normalized EMG amplitude and force platform data were averaged over five trials for each participant and analyzed using repeated-measures ANOVA. During the takeoff phase in jumps with one-footed landings, the non-landing limb loaded more than the landing limb (p= 0.003). During the 100 ms prior to initial contact, single-footed landings generated higher EMG values than two-footed landings (p= 0.004). One-footed landings resulted in higher peak vertical loading, lateral loading, and rate of lateral loading than two-footed landings (p< 0.05). Trends were observed indicating that muscle activation during one-footed landings is greater than for two-footed landings (p= 0.053 vs.p= 0.077). The greater forces and rate of loading produced during single-limb landings implies a higher predisposition to injury. It appears that strategic planning and training of jumps in volleyball and other jumping sports is critical.

scholarly journals Volitional Spine Stabilization During a Drop Vertical Jump From Different Landing Heights: Implications for Anterior Cruciate Ligament Injury

2016 ◽  
Vol 51 (12) ◽  
pp. 1003-1012 ◽  
Author(s):  
Ram Haddas ◽  
Troy Hooper ◽  
C. Roger James ◽  
Phillip S. Sizer
Keyword(s):  
Anterior Cruciate Ligament ◽  
Lower Extremity ◽  
Injury Risk ◽  
Muscle Activation ◽  
Cruciate Ligament ◽  
Vertical Jump ◽  
Ligament Injury ◽  
Lower Extremity Muscle ◽  
Anterior Cruciate ◽  
Drop Vertical Jump

Context:Volitional preemptive abdominal contraction (VPAC) during dynamic activities may alter trunk motion, but the role of the core musculature in positioning the trunk during landing tasks is unclear.Objective:To determine whether volitional core-muscle activation incorporated during a drop vertical jump alters lower extremity kinematics and kinetics, as well as trunk and lower extremity muscle activity at different landing heights.Design:Controlled laboratory study.Setting:Clinical biomechanics laboratory.Patients or Other Participants:Thirty-two young healthy adults, consisting of 17 men (age = 25.24 ± 2.88 years, height = 1.85 ± 0.06 m, mass = 89.68 ± 16.80 kg) and 15 women (age = 23.93 ± 1.33 years, height = 1.67 ± 0.08 m, mass = 89.68 ± 5.28 kg).Intervention(s):Core-muscle activation using VPAC.Main Outcome Measure(s):We collected 3-dimensional ankle, knee, and hip motions, moments, and powers; ground reaction forces; and trunk and lower extremity muscle activity during 0.30- and 0.50-m drop vertical-jump landings.Results:During landing from a 0.30-m height, VPAC performance increased external oblique and semitendinosis activity, knee flexion, and knee internal rotation and decreased knee-abduction moment and knee-energy absorption. During the 0.50-m landing, the VPAC increased external oblique and semitendinosis activity, knee flexion, and hip flexion and decreased ankle inversion and hip-energy absorption.Conclusions:The VPAC performance during landing may protect the anterior cruciate ligament during different landing phases from different heights, creating a protective advantage just before ground contact and after the impact phase. Incorporating VPAC during high injury-risk activities may enhance pelvic stability, improve lower extremity positioning and sensorimotor control, and reduce anterior cruciate ligament injury risk while protecting the lumbar spine.

The Relationship Between Joint Stiffness and Muscle Activity in Unstable Ankles and Copers

2017 ◽  
Vol 26 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Alan R. Needle ◽  
Thomas W. Kaminski ◽  
Jochen Baumeister ◽  
Jill S. Higginson ◽  
William B. Farquhar ◽  
...  
Keyword(s):  
Outcome Measures ◽  
Tibialis Anterior ◽  
Muscle Activation ◽  
Joint Stiffness ◽  
Ankle Injury ◽  
Group Differences ◽  
Injury Rehabilitation ◽  
Ankle Stiffness ◽  
History Of ◽  
The Relationship

Context:Rolling sensations at the ankle are common after injury and represent failure in neural regulation of joint stiffness. However, deficits after ankle injury are variable and strategies for optimizing stiffness may differ across patients.Objective:To determine if ankle stiffness and muscle activation differ between patients with varying history of ankle injury.Patients:Fifty-nine individuals were stratified into healthy (CON, n = 20), functionally unstable (UNS, n = 19), and coper (COP, n = 20) groups.Main Outcome Measures:A 20° supination perturbation was applied to the ankle as position and torque were synchronized with activity of tibialis anterior, peroneus longus, and soleus. Subjects were tested with muscles relaxed, while maintaining 30% muscle activation, and while directed to react and resist the perturbation.Results:No group differences existed for joint stiffness (F = 0.07, P = .993); however, the UNS group had higher soleus and less tibialis anterior activation than the CON group during passive trials (P < .05). In addition, greater early tibialis anterior activation generally predicted higher stiffness in the CON group (P ≤ .03), but greater soleus activity improved stiffness in the UNS group (P = .03).Conclusion:Although previous injury does not affect the ability to stiffen the joint under laboratory conditions, strategies appear to differ. Generally, the COP has decreased muscle activation, whereas the UNS uses greater plantar-flexor activity. The results of this study suggest that clinicians should emphasize correct preparatory muscle activation to improve joint stiffness in injury-rehabilitation efforts.

scholarly journals Changes in force production after applying PNF

2021 ◽  
Vol 31 (Supplement_2) ◽  
Author(s):  
Vitor Ferreira Vitor Ferreira
Keyword(s):  
Muscle Activation ◽  
Statistical Significance ◽  
Vertical Jump ◽  
Force Production ◽  
Experimental Protocol ◽  
Average Force ◽  
Control Protocol ◽  
Before And After ◽  
Quasi Experimental ◽  
And Control

Abstract Background The performance of the vertical jump can benefit from techniques that enhance muscle strength. The application of certain PNF techniques can improve muscle activation and consequently the production of strength. The objective of this study was to understand the immediate changes produced by the application of the PNF Slow Reversal technique in the performance of the vertical jump. Methods An analytic, quasi-experimental and crossover study was designed. The data were collected in two sessions with at least 48 hours between them. In each session, three countermovement jumps were collected before and after the experimental and control protocol in a randomized order. The experimental protocol consisted of two diagonals of Slow Reversal technique with 15 repetitions of each. The control protocol consisted of 5 minutes of sitting (approximately the same time as the experimental protocol). The data were collected on a force platform and processed using an algorithm in MATLAB R2016b software. Results 18 female (mean age 20.7 ± 2.7 years, mean body mass of 71.6 ± 11.5 kg, mean height of 1.75 ± 0.07 m) athletes of amateur sports participated in the study. Some values with statistical significance were found. Particularly a decrease in the average force production in the concentric phase after the application of PNF (P = 0.024). Conclusions The application of PNF seems to induce acute effects in the production of force, in the performance of the vertical jump. The application of PNF may induce muscle adaptations that need to be better studied in the long term.

Sign in / Sign up

Export Citation Format

Share Document