Download or read book The Effect of Landing Type on Kinematics Kinetics and Muscle Activity During Landing written by Sarah E. Hovey and published by . This book was released on 2016 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Decision Making on Landing Neuromechanics as a Function of Task and Sex written by Melissa A. Mache and published by . This book was released on 2010 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the incidence of non-contact anterior cruciate ligament (ACL) injuries is greater among women than men athletes, the factors that contribute to this greater risk of injury are not well understood. One relevant question is whether decision making during landing influences the biomechanical and neuromuscular factors thought to contribute to ACL injury, and whether these effects differ as a function of task and sex. The purpose of this study was thus to examine the effects of decision making on the neuromechanics of two-footed landing tasks in women and men. Twenty-nine healthy young adults (13 women; 16 men) completed a series of two-footed drop landing and drop-jump tasks under preplanned and decision-making conditions. Biomechanical and electromyographic data were collected. Repeated measures ANOVA was used to determine the effect of decision making on hip, knee, and ankle kinematics and kinetics, and on proactive and reactive muscle activity, as a function of task and sex. Multiple linear regression was used to assess the relationship between select knee biomechanical variables and proactive muscle activity. Decision making had numerous effects on lower extremity kinematics, kinetics, and neuromuscular control, many of which were task-specific. Under decision-making conditions, individuals exhibited similar joint postures at initial ground contact and similar amounts of reactive muscle activity across tasks. The majority of the observed modifications in neuromechanics suggested a default towards the preplanned drop landing strategy under decision-making conditions. Some effects of decision making on joint mechanics and reactive muscle activity varied with sex, although the extent to which these dissimilar effects modified relative ACL loading is not known. Knee flexion at initial contact, peak knee abduction, and peak knee adduction moment were significantly related to the proactive activity of several, primarily lateral, muscles of the lower extremity, independent of task and decision-making condition. These results indicate that decision making influences landing mechanics and neuromuscular control and that these effects are generally task-dependent and, in some cases, sex-dependent. The results also suggest that, in both women and men, drop landings and drop-jumps performed under decision-making conditions are no more dangerous, with respect to ACL loading, than preplanned drop landings.

Download or read book The Effects of a Functional Fatigue Protocol on Landing Kinetics and Kinematics of the Lower Extremity written by Ashley S. Long and published by . This book was released on 2005 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discussion. Significant changes in time to peak GRF, time to peak of maximum knee flexion, muscle activation and temporal patterning may suggest a kinematic difference in landing form in a fatigued state.

Download or read book The Effect of Gluteus Medius Muscle Activation on Lower Limb Three dimensional Kinematics and Kinetics in Male and Female Athletes During Three Drop Jump Heights written by Stephanie Christine Nowak and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Women are four to eight times more likely to injure their anterior cruciate ligament (ACL) compared to men. It is most commonly injured through a non-contact mechanism during game time situations. During landings, women display valgus collapse, where a less active gluteus medius muscle (GMed) may be unable to control the internal rotation of the thigh, causing an increase in knee joint abduction angle, augmenting the risk of ACL injury. This study's purpose was to determine the difference between 12 male and 12 female athletes in muscle activity, specifically the GMed, and the 3D kinematics and kinetics of the lower-limb during drop jump landings from three heights; maximum vertical jump height, tibial length, and a commonly used height of 40cm. Results showed that females had greater hip adduction and knee abduction angles compared to men. The GMed activity showed no significant differences between sexes at each drop jump height.

Download or read book The Effects of a Soccer specific Vertical Jump on Landing Mechanics written by Sophia Mancini and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Anterior cruciate ligament (ACL) injury frequently occurs in female soccer athletes during deceleration movements such as landings. In soccer, landings mostly occur following jumping headers. Little research has been done to determine the mechanics that follow and how they compare to standard drop vertical jumps (DVJ). The purpose of this study was to analyze differences between jumps and landings in kinematics, kinetics, and muscle activation patterns in female soccer athletes to better assess the sport-specific risk for ACL injury. It was hypothesized that more biomechanical tendencies associated with ACL risk factors would emerge from soccer-specific vertical jumps (SSVJ) compared to DVJs and second landings (L2) compared to first landings (L1). Methods: 8 female participants (20.88 ± 1.17 years; 1.68 ± 0.06 m; 58.77 ± 7.65 kg) performed DVJs and SSVJs. Motion capture, force, and electromyography (EMG) data were collected to calculate joint motion, loading, and muscle activation throughout landing phases. Data were analyzed using RM-ANOVA, collapsed across jump (DVJ vs. SSVJ) and landing (L1 vs. L2). Results: Significant findings were revealed in all categories, however, kinematic variables were the most profound results. Significantly higher jump height was achieved in DVJs (p=0.008). SSVJs and L2s produced less peak hip (p=0.03; d=0.817) (p=0.007; d=1.566) and knee 2 (p=0.002; d=0.732) (p=0.002; d=1.476) flexion during landing, respectively. A significant interaction was present for trunk flexion at initial contact (p=0.034). Follow-up tests revealed no significant differences following headers. Discussion: SSVJ-L2s displayed a more erect landing at the hip and knee, a known ACL risk factor, however, it is unclear whether these results are due to trunk movement during heading. Limited results in kinetic and EMG variables may be explained by the difference in jump height achieved, therefore further investigation in a more elite population is required. Additionally, SSVJs may be a good sport-specific screening tool.

Download or read book Sex Specific Neuromuscular and Kinematic Analysis of Unanticipated Single leg Landings In Young Athletes written by Nicholas Romanchuk and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the higher incidence of anterior cruciate ligament injuries in pediatric female populations, limited research has investigated sex-differences in youth biomechanics. Furthermore, research involving jump mechanics typically requires participant to follow a set protocol, such as sticking the landing. To reduce variability and improve reliability, trails where participants fail to meet the required protocol are discarded; however, significant clinical findings may be elucidated from these trials. The purpose of this thesis was to provide a complete biomechanical analysis of unanticipated single-leg drop-jump landings in youth athletes. Thirty-two healthy youth athletes completed unanticipated single-leg drop-jump landings on their dominant limb. Trials where participants shifted foot position or touched the ground with the contralateral leg were categorized as failed. Drop-jump landings were time-normalized using landmarks within the drop-jump task. Statistical parametric mapping (SPM) determined time-varying sex-differences in muscle onset time, co-activation, kinematics and kinetics. Wilcoxon signed-rank tests and paired sample t-tests compared lower-limb kinematics, centre-of-mass excursion and muscle activation amplitudes during the successful and failed landings. A logistic regression model was also fit to predict the likelihood of a successful landing. SPM identified significantly greater trunk flexion angle in males during the deceleration, flight, and landing phase of the drop-jump. Greater quadriceps-gastrocnemius co-activation was identified during the flight phase in female participants and independent sample t-test identified longer muscle onset time in the vastus lateralis of male participants. When comparing failed and successful landings greater hip abduction and less external rotation angles were observed during the successful trials. In addition, greater preparatory muscle activation was observed in the rectus femoris and semitendinosus during the flight phase of the failed landings. A logistic regression model, which included eight kinematic and neuromuscular variables, offered a training classification accuracy of 70% and a leave-one-out cross-validation accuracy of 65%. In conclusion, females land in a more erect posture and may be less effective at dissipating landing forces. In addition, greater co-activation and shorter pre-activations of the lower limb musculature may indicate a less effective muscle activation strategy in females. Furthermore, hip kinematics and the surrounding musculature play an important role in controlling successful and failed unanticipated landings. The variables included in the logistic regression model indicate which key factors are linked to landing a jump successfully. Training modalities aimed at improving landing mechanics should therefore focus on modifying these variables.

Download or read book The Jump Landing Impact Absorption Kinematics and Kinetics written by Dong-Min Shin and published by . This book was released on 1992 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Acute and Delayed Effects of an Exhaustive Bout of Exercise on Landing Biomechanics in Women and Men written by Kristof Kipp and published by . This book was released on 2010 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although female athletes are at greater risk of non-contact knee injuries than men, the factors that contribute to these injuries are not well understood. One important question is whether intense exercise influences the risk of knee injury, both acutely and over the following days. The purpose of this study was thus to evaluate the acute and delayed effects of an intense bout of exercise on risk factors associated with knee injury in women and men. Fifteen each of healthy young women and men performed two testing sessions, 44-52 hours apart. In each session, biomechanical data were collected during execution of sets of 10 drop vertical jumps. An initial set of drop vertical jumps was compared to a set performed immediately after an intense exercise bout on the first day and to a set performed on the second day to determine the acute and delayed effects of fatigue, respectively. A two-way repeated measures ANOVA was used to determine the effect of the exercise bout on risk factors associated with knee injury during the jump task in women and men. Intense exercise had immediate effects on joint kinematics and kinetics, patterns of joint motion and moments, and the variability of joint couplings. The acute kinematic and kinetic changes at the hip and ankle were consistent with compensatory strategies, whereas changes at the knee were consistent with an increased risk of injury. The same appeared to be true for the patterns of joint motions and moments. Acute changes in the variability of inter- and intra-limb joint couplings were also consistent with compensatory modifications of lower limb biomechanics. Delayed effects were limited to patterns of joint motion and moments, and reflected jointdependent combinations of compensatory strategies or mechanical changes that could increase knee injury risk. Although intense exercise had acute and prolonged effects on several biomechanical variables, none of the effects depended on the sex of participants. These results indicate that intense exercise has immediate and prolonged effects on landing biomechanics, independent of sex. While the majority of changes point to a compensatory strategy, a few were consistent with increased risk of knee injury.

Download or read book Abdominal Fatigue and Lower Extremity Kinematics During a Drop Landing in Females written by Eryn Murphy and published by . This book was released on 2015 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Learned Biomechanics Through Feedback written by Laura Young and published by . This book was released on 2013 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a critical need to develop cost and time-effective prophylactic interventions to decrease the risk of anterior cruciate ligament (ACL) injury. Currently, jumplanding feedback interventions have demonstrated the ability to alter movements that increase the risk of ACL injury during landing. Unfortunately, it remains unknown if jump-landing interventions, which demonstrate the ability to alter movements during a jump-landing task, can alter similar movements in a different task, such as a cutting maneuver. The specific aims of this randomized control trial was to determine the effects of a jump landing feedback intervention on 1) the kinetics and 2) the kinematics performed during an anticipated cutting maneuver and a jump-landing task compared to a control group. Our central hypothesis was that biomechanical alterations known to occur during a jump-landing task, following a jump landing feedback intervention, will also be altered during a cutting maneuver. We used separate repeated measures ANOVAs to evaluate differences in kinetics and kinematics between feedback and control groups overtime. The results of this study revealed a significant decrease in peak vertical ground reaction force (VGRF) in the feedback group during the jump landing task but not the cutting task. Neither group improved knee flexion angles during the jump landing task, while the feedback group became more extended at the knee joint compared to the control during the cutting task. Both groups demonstrated an improvement in hip flexion over time in the jump landing task, but not the cutting task. Lastly, neither group demonstrated a change in knee abduction angles during either of the tasks. The findings of the study do not entirely support our hypotheses, but we would expect to find more differences with more participants added to the sample size. While the results were not what we expected, they have provided us with insight into the limitations of a feedback intervention and in order to improve future prevention programs, it is imperative to understand the limitations of the feedback intervention.

Download or read book The Effect of Load on the Kinetics and Kinematics of the Lower Extremity During Landing written by Michael Sullivan and published by . This book was released on 2021 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Purpose: To understand the differences in the lower extremity kinetics and kinematics as load increases during jump landings. Methods: Ten male participants (20.4 years ℗ł 2.41 years, 108.8kg ℗ł 14.02kg) took part in two testing sessions. The first testing session involved testing each participant's 1-repetition max in the hexagonal barbell deadlift. The second testing session involved the data collection of the jumping trials for each participant. Participants performed their countermovement jumps under seven randomized conditions. Six of the conditions involved the hex bar using loads equivalent to 10, 20, 30, 40, 50, and 60% estimated 1-repetition max of the hexagonal barbell deadlift. The seventh condition was an unloaded (bodyweight or 0%) countermovement jump. Peak values for joint powers, moments, angles, and velocities were recorded for the ankle, knee, and hip for all participants and conditions. A repeated measures ANOVA was used to compare differences among results. Results: Significant differences (p

Download or read book Human Movement and Motor Control in the Natural Environment written by Peter A Federolf and published by Frontiers Media SA. This book was released on 2023-06-08 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The basic understanding of human movement and control of human movement stems largely from laboratory measurements where human movement can be quantified with high precision and accuracy, but where the artificial environment compromises ecological validity. A good example for this issue was demonstrated in a recent investigation; specifically that the walking gait pattern of healthy individuals in a laboratory changed as a function of how many researchers were present during the experiment. Observations like these underscore that study volunteers adapt their behavior to the specific laboratory environment and warrant the question of how well we can transfer our lab-based understanding of gait patterns and the underlying neuromuscular control system to walking during daily living. Another research area where lab-based movement assessments have led to conflicting findings is the field of sports injury prevention: Many neuromuscular training programs have been shown to be effective in reducing the sport injury rate in athletes by 30-50% or more in a variety of different multi-directional sports. Nevertheless, lab-based assessments of the same athletes who completed those training programs were often not able to detect improvements in motor control of sport-specific movements or a reduction in joint loading, two factors thought to be closely linked with sport injury risk. This disconnect suggests that lab-based assessments of movement and motor control are often poor indicators of player behavior during real-game scenarios and may limit our ability to screen athletes for injury risk or monitor their progress in rehabilitation. These examples highlight that we should strive for the assessment and investigation of human movement and motor control in natural environments, i.e. where individuals, patients, athletes, or other groups of interest perform, explore, and interact under real-world conditions.

Download or read book An Analysis of Preferred Action Leg and Preferred Balance Leg Kinetics and Kinematics During Single Leg Drop Landings written by Mitchell D. Waller and published by . This book was released on 2008 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sex Differences in Kinematics and Kinetics During a Rotational Jump Landing and Unanticipated Cutting Maneuver written by Joshua L. Baker and published by . This book was released on 2009 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of a Six week Strength training Program on Landing Kinematics and Kinetics of Female Collegiate Besketball Athletes written by Patricia Ann McGinn and published by . This book was released on 2004 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Tilted Surfaces on Ankle Kinematics and EMG Activities in Landing written by Divya Bhaskaran and published by . This book was released on 2010 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to examine the effects of landing on a combined inverted and plantarflexed surface on the ankle kinematics and electromyographic (EMG) activities of the medial gastrocnemius (MG), peroneal longus (PL) and anterior tibialis muscles (TA). Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to each of these surfaces: a flat surface, a 25° inversion surface (inverted), and a combined surface (combined) of 25° inversion and 25° plantarflexion. The three dimensional kinematic variables and integrated EMG (IEMG) of the three muscles were assessed using one-way repeated measures analysis of variance (ANOVA, p

Download or read book The Effects of Static Stretching on Muscle Activity During a Drop Landing written by Wesley R. Moss and published by . This book was released on 2007 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Setting: Human Performance Research Center.