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Book The Effect of Ankle Bracing on Knee Joint Kinematics and Kinetics During Repeated Single Leg Hop and Drop Vertical Jump in High School Aged Girls

Download or read book The Effect of Ankle Bracing on Knee Joint Kinematics and Kinetics During Repeated Single Leg Hop and Drop Vertical Jump in High School Aged Girls written by Virginia Norene Christensen and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Ankle bracing has not been studied for its effects of knee joint kinematics and kinetics in the adolescent female athlete. Hypothesis: A) A statistically significant mean increase of knee joint valgus and extensor moments and valgus angles would be found in the braced group during the drop vertical jump and the single log hop tests and B) A statistically significant mean decrease in knee joint varus and extensor moments and valgus angles will be found between pre- and post-test acclimation periods in the braced condition. Study Design: Randomized Controlled Trial. Methods: Fifteen adolescent female athletes performed Drop Vertical Jump (DVJ) and Single Leg Hop (SLH) tests without ankle bracing and with a lace-up style ankle brace. Subjects wore braces over a 1 week period and retested. Results: During the DVJ, bracing increased knee extensor moments during the first 50 ms of landing but had no affect on knee frontal plane moments. Bracing increased vertical ground reaction force (vGRF) within the first 50ms of landing, and peak vGRF with less time to achieve peak vGRF. During the SLH, bracing increased knee flexion at IC and decreased knee frontal plane displacement into valgus. Ankle bracing increased vGRF within the first 50ms of landing and decreased stance time. Conclusions: Ankle bracing increased vGRF and knee extensor moments during the first 50ms of landing. Clinical Relevance: The adolscent female athlete may be at risk for knee injury during the initial landing phse when wearing a lace-up style ankle brace.

Book The Effects of Prophylactic Ankle Bracing on Knee and Hip Mechanics in Basketball Players During Jump Landing

Download or read book The Effects of Prophylactic Ankle Bracing on Knee and Hip Mechanics in Basketball Players During Jump Landing written by Riann K. Thayer and published by . This book was released on 2018 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background: Many athletes of various sports have been required to wear ankle braces for prophylactic uses. Ankle braces have been shown to decrease range of motion in all directions, which means the main force absorption mechanism of the ankle may be inhibited. This decrease in force absorption at the ankle may increase the mechanical demands at the more proximal knee and hip joints. In this study, the change in knee, hip and lower back mechanics will be investigated to gain understanding as to whether bracing the ankle could create a higher injury potential. Methods: In this study, 12 intercollegiate basketball players (6 female, 6 male) participated during one session, in which each subject tested for each taping condition (self-adherent, adhesive cloth, and no tape). For each trial, the participants performed three maximum vertical jump trials and three depth drop trials, a 15-minute bout of exercise, and subsequently three more maximum vertical jumps and three more depth drops. The participants' lower body kinematics and kinetics were measured using 3D motion capture and force plates. Results: Analysis of ankle bracing pre- and post-exercise on lower extremity kinematics and kinetics through a two-way MANOVA yielded results that were not significant for any of the variables, including their interaction effect. There was no effect of the three different types of ankle bracing (control, adhesive, and self-adhesive), exercise (pre-and post-), or the interaction of those variables on peak hip flexion, peak knee flexion, peak knee moment, peak hip moment, and peak lumbosacral moment. Conclusion: Ankle bracing had no effect on selected lower body kinematics and kinetics. More research should be done to better understand whether ankle bracing has the potential to increase injury at other joints.

Book The Effect of Ankle Prophylactic Bracing on Kinematics of the Lower Body when Landing from a Vertical Jump

Download or read book The Effect of Ankle Prophylactic Bracing on Kinematics of the Lower Body when Landing from a Vertical Jump written by Joshua Paul Rayburn and published by . This book was released on 2014 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study is to investigate the effects of the ASO ankle brace and the closed Gibney ankle taping method on kinematics of the lower body when landing from a vertical jump. By observing lower limb joint angular kinematics during landing this study may help to identify if ankle prophylactic bracing may increase the potential risk of injury to the more proximal unstabilized knee and hip joints. For this study, 10 females (age: 18-24 years), were randomly selected from a group (N= 24) of well-trained intercollegiate athletes, who had been competitive for at least 4 years in a jumping sport.

Book Ankle Bracing as a Mediator of the Influence of Attentional Foci on Landing Mechanics in Healthy Females

Download or read book Ankle Bracing as a Mediator of the Influence of Attentional Foci on Landing Mechanics in Healthy Females written by Mackenzie Haines and published by . This book was released on 2018 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Context: Biomechanics risk factors observed during landing task have been identified such as decreased hip and knee flexion, increased knee valgus, hip adduction and hip external rotation. These patterns have been related to the increase risk for ACL injury and could also be observed with decreased ankle range of motion (ROM). The effects of different forms of attentional focused instruction has been studied and is thought to optimize landing mechanics; decreasing risk for ACL injury. This has not yet been explored in a population with an external mechanical restriction such as an ankle brace. Objective: To determine the effects of lace-up ankle bracing and attentional focused instruction on lower extremity kinematics and kinetics during a landing task in healthy females Design: Crossover. Setting: Laboratory. Participants: 19 healthy females. Inclusion: aged 18-35, physically active with minimal familiarity of drop vertical jump task (DVJ). Exclusion: lower extremity musculoskeletal injury within last 6 months, history of lower extremity injury, vestibular, balance or connective tissue disorders, or history of ankle sprains. Interventions: Independent variables included condition (brace vs. no brace) and mode of attentional focus (external focus (EF) , internal focus (IF), neutral). All participants completed five DVJ trails for each different modes of attentional focus instruction for both bracing conditions. Main Outcome Measures: 3D trunk and lower extremity kinematics and kinetics were analyzed during landing phase of DVJ from initial contact to peak knee flexion Results: Bracing decreased peak ankle dorsiflexion (19.6°± 6.4° vs 25.9°± 5.3°) compared to non-braced. In the bracing vs. nonbraced condition, EF increased peak hip abduction (-3.8°±5.0° vs. -1.7°±4.2°), hip flexion (83.6°±14.3° vs. 79.0°±16.1°), and decreased knee valgus (-13.8°±6.6° vs. - 14.9°± 6.9°). Conclusion: EF instruction can aid in optimizing landing mechanics in healthy female population with mechanical restriction at the ankle is in place.

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

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.

Book The Kinematic and Kinetic Effects of Fatigue on Vertical Jumping

Download or read book The Kinematic and Kinetic Effects of Fatigue on Vertical Jumping written by Scott Douglas Betty and published by . This book was released on 1994 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Effect of Knee Bracing on Vertical Jump 40 yard Dash and Leg Strength

Download or read book The Effect of Knee Bracing on Vertical Jump 40 yard Dash and Leg Strength written by Salvatore S. Ballachino and published by . This book was released on 1985 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Effects of Ankle Bracing and Fatigue on Time to Stabilization in Subjects with Chronic Ankle Instability

Download or read book The Effects of Ankle Bracing and Fatigue on Time to Stabilization in Subjects with Chronic Ankle Instability written by Sari L. Cattoni and published by . This book was released on 2010 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is unknown whether the application of an ankle brace can increase dynamic stability to overcome the effects of fatigue in those individuals with CAI. Ankle dynamic stability was assessed before and after a functional fatigue protocol using the Time to Stabilization (TTS) method. Prior to the functional task, dynamic stability was measured using a single leg jump landing at 50% of the subjects' maximum vertical jump height. The functional fatigue circuit was repeated until the time it took to complete the circuit increased to 50% of the baseline time. Immediately after fatigue was reached, the single leg jump landing measures were repeated. This protocol was performed with and without an ankle brace. For APTTS, the main effect for Group was statistically significant (F= 4.15; p= .05). Subjects in the CAI group (1.291"0.179s) took significantly longer to stabilize than those in the healthy group (1.191"0.10s). There were no other significant results found. The results of our study provide questions regarding the use of ankle braces for improving dynamic stability measured with TTS in both a healthy population and those with CAI. Further research, with a larger sample size should be conducted to make a better decision regarding the effectiveness of ankle braces in improving single-leg jump landing stabilization.

Book Acute and Delayed Effects of an Exhaustive Bout of Exercise on Landing Biomechanics in Women and Men

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.

Book Effects of Exercise Induced Muscular Fatigue on the Kinetics and Electromyographic Activity of a Single leg Vertical Jump in Healthy Men

Download or read book Effects of Exercise Induced Muscular Fatigue on the Kinetics and Electromyographic Activity of a Single leg Vertical Jump in Healthy Men written by Thomas Kevin Robinson and published by . This book was released on 2004 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Purpose/Hypotheses: The knee is the most commonly injured major joint, with approximately 80,000 anterior cruciate ligament (ACL) injuries annually. Epidemiological studies of sporting events show that knee injury frequency increases during during the latter portion of the game, thus injury may be associated with biomechanical changes induced by fatigue. We investigated the bilateral effects of unilateral lower extremity (LE) extensor muscle fatigue on electromyographic (EMG) patterns, kinematics, and kinetics of the single-leg vertical jump. Subjects: 15 healthy males, 22-29 years old. Methods: Subjects performed 5 maximal single-leg vertical jumps with each leg. Bilateral EMG (gluteus medius, vastus medialis and lateralis, medial and lateral hamstrings, gastroc/soleus), 3D lower extremity motion and ground reaction forces (GRF) from the jumping/landing leg were collected simultaneously. Subjects exercised the dominant LE (plant leg when kicking a ball) on a leg press machine to fatigue (unable to perform a complete leg press against resistance of 30% of body weight), then single-leg vertical jumps were repeated. Data were exracted in relation to landing events - initial force plate contact and the peak vertical GRF. EMG data were averaged across 5 trials and normalized as a percentage of the pre-exercise value for each muscle. Data analysis used repeated measures ANOVA and MANOVA. Results: There were significant interactions between limb dominance and fatigue for frontal plane knee valgus/varus moment (p=.035; larger on the dominant knee after exercise) and peak vertical GRF (p=.013; lower on the dominant leg after exercise). There was also a main effect of fatigue on peak anterior shear ground reaction force (p=.008; greater for the dominant leg after exercise). The dominant leg had significantly greater EMG activity of the gluteus medius and medial hamstring muscle groups. Conclusion: Despite reduced vertical and anterior GRF following exercise, landing from a single-leg vertical jump produced greater knee valgus moments and more EMG activity in the gluteus medius ad medial hamstring muscle groups in the dominant (exercised) leg and greater lateral hamstring and gastroc/soleus EMG activity in the non-dominant leg. Clinical Relevance: The change in post-fatigue forces in the dominant limb, particularly increased knee valgus moments, may increase the risk of ACL injury. The post-fatigue increase in gluteus medius and medial hamstring activity may be compensatory strategies to counteract the potentially damaging forces.