scholarly journals The Effects of Internal Attention on Knee Biomechanics in Volleyball Spike Jump through Augmented Video Feedback

2021 ◽  
Vol 11 (5) ◽  
pp. 541
Author(s):  
Aiwen Wang ◽  
Xiaohan Li ◽  
Huiming Huang
Keyword(s):  
Angular Velocity ◽  
Internal Rotation ◽  
Injury Risk ◽  
Reaction Force ◽  
Statistical Parameter ◽  
Video Feedback ◽  
Flexion Angle ◽  
Initial Contact ◽  
Knee Biomechanics ◽  
Flexion Moment

Poor knee biomechanics in a volleyball spike jump generally result in a higher knee injury risk, which can be altered by an internal focus of attention (FOA). The constrained action hypothesis (CAH) purports that the FOA inhibits sports performance whereas no ecologically valid evidence has been found in previous studies. The purpose of this research is to explore the effect of video feedback on knee biomechanics in a volleyball spike jump including landing and take-off phases. The video feedback was performed in a natural way. Fourteen volleyball male players were recruited in this study. A paired t-test was used to detect the effect of the feedback; meanwhile, statistical parameter mapping (SPM) statistics were used for the continuum differences during movement. After biofeedback, the initial contact flexion angle of the knee (t = 2.179, p = 0.049), the maximal flexion angle of the knee (t = 3.242, p = 0.006) and the maximal internal rotation angular velocity of the knee (t = 5.209, p = 0.003) increased significantly; the maximal extension moment of the knee (t = 3.962, p < 0.001) and the maximal flexion moment of the knee (t = −3.711, p = 0.002) significantly decreased; the maximal abduction moment significantly decreased (t = 3.069, p = 0.037) but the maximal internal rotation moment significantly increased (t = 2.813, p = 0.018); the first peak of the vertical ground reaction force (vGRF) (t = 7.618, p < 0.001) and the average loading rate to the first peak (t = 4.205, p = 0.004) significantly decreased; the other peaks of the vGRF were not found to have differences; a larger knee flexion was found during the phase from 31.17 to 73.19% (t = 2.611, p = 0.012); a larger adduction angular velocity was found during the phase from 49.07 to 62.46% (t = 3.148, p = 0.004); a smaller external rotational angular velocity was found during the phase from 45.85 to 49.96% (t = 5.011 p = 0.017); there was an increased flexion moment of the knee during the phase from 19.72 to 21.38% (t = 0.029, p = 0.029) and an external moment of the knee during the phase from 85.55 to 95.06% (t = 4.214, p < 0.001); the vGRF significantly decreased during the phase from 3.13 to 5.94% (t = 4.096, p = 0.014) and 19.83–21.97% (t = 4.096, p = 0.024) but significantly increased in the phase of 91.43–100% (t = 4.096, p < 0.001). The impulse of the vGRF and knee power were not found to be different compared with before biofeedback. Therefore, our study suggests video feedback in a natural practice has the potential to improve knee movement whilst not altering the performance in a volleyball spike jump. This indicates that the CAH theory is possibly not suitable in a real competition. Due to the complexity of human movements and the limitations of this study, muscle activities must be considered in the future.

scholarly journals Effects of Video Task With a High-Level Exercise Illustration on Knee Movements in Male Volleyball Spike Jump

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiangyu Liu ◽  
Huiming Huang ◽  
Xiaohan Li ◽  
Jianshe Li ◽  
Huijuan Shi ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Knee Flexion ◽  
External Rotation ◽  
Knee Injuries ◽  
Statistical Parametric Mapping ◽  
Flexion Angle ◽  
Knee Biomechanics ◽  
Knee Flexion Angle ◽  
Flexion Moment ◽  
High Level

Hazardous knee biomechanics, such as excessive knee affordance link with injuries in volleyball spike jumps (SPJs) and can be reconfigured by the enhancement of internal focus. The study aimed to explore the effects of video tasks illustrating a high-level SPJ on knee movement in the volleyball SPJ with 15 elite male volleyball athletes. This study investigated the knee movements in sagittal, coronal, and transverse planes before and after the video task in SPJ using one-dimensional statistical parametric mapping (SPM 1D) and discrete statistics. The SPM 1D indicated a larger knee flexion angle (31.17–73.19%, t = 2.611, and p = 0.012), increased knee flexion moment (19.72–21.38%, t = 0.029, and p = 0.029), and increased knee adduction angular velocity (49.07–62.64%, t = 3.148, and p = 0.004) after video task; alternatively, smaller knee external rotation angular velocity (45.85–49.96%, t = 5.199, and p = 0.017) and vertical ground reaction (vGRF) (3.13–5.94%, t = 4.096, and p = 0.014; 19.83–21.97%, t = 4.096, and p = 0.024) were found after the task. With discrete value statistics, the video task increased the peak of knee flexion angle while decreased the peak of extension moment, flexion moment, abduction moment, external moment, the first peak vGRF, and related loading rate.Conclusions: The results indicate that knee biomechanics in volleyball SPJ positively influenced by the video task. The task has the athletes control the knee movements more actively and improves the original hazardous movement strategies. Therefore, the video task presumably can abate the occurrence of knee injuries in volleyball SPJ. Further validation especially in the exercise effect is needed in the future.

Quadriceps and Hamstrings Fatigue Alters Hip and Knee Mechanics

2010 ◽  
Vol 26 (2) ◽  
pp. 159-170 ◽  
Author(s):  
Abbey C. Thomas ◽  
Scott G. McLean ◽  
Riann M. Palmieri-Smith
Keyword(s):  
Repeated Measures ◽  
Injury Risk ◽  
Mixed Model ◽  
External Rotation ◽  
Reaction Force ◽  
Acl Injury ◽  
Knee Extension ◽  
Initial Contact ◽  
Knee Mechanics ◽  
Acl Injury Risk

Neuromuscular fatigue exacerbates abnormal landing strategies, which may increase noncontact anterior cruciate ligament (ACL) injury risk. The synergistic actions of quadriceps and hamstrings (QH) muscles are central to an upright landing posture, though the precise effect of simultaneous fatigue of these muscles on landing and ACL injury risk is unclear. Elucidating neuromechanical responses to QH fatigue thus appears important in developing more targeted fatigue-resistance intervention strategies. The current study thus aimed to examine the effects of QH fatigue on lower extremity neuromechanics during dynamic activity. Twenty-five healthy male and female volunteers performed three single-leg forward hops onto a force platform before and after QH fatigue. Fatigue was induced through sets of alternating QH concentric contractions, on an isokinetic dynamometer, until the first five repetitions of a set were performed at least 50% below QH peak torque. Three-dimensional hip and knee kinematics and normalized (body mass × height) kinetic variables were quantified for pre- and postfatigue landings and subsequently analyzed by way of repeated- measures mixed-model ANOVAs. QH fatigue produced significant increases in initial contact (IC) hip internal rotation and knee extension and external rotation angles (p< .05), with the increases in knee extension and external rotation being maintained at the time of peak vertical ground reaction force (vGRF) (p< .05). Larger knee extension and smaller knee fexion and external rotation moments were also evident at peak vGRF following fatigue (p< .05). Females landed with greater hip fexion and less abduction than males at both IC and peak vGRF as well as greater knee fexion at peak vGRF (p< .05). The peak vGRF was larger for females than males (p< .05). No sex × fatigue effects were found (p> .05). Fatigue of the QH muscles altered hip and knee neuromechanics, which may increase the risk of ACL injury. Prevention programs should incorporate methods aimed at countering QH fatigue.

Effects of Volitional Spine Stabilization and Lower-Extremity Fatigue on the Knee and Ankle During Landing Performance in a Population With Recurrent Low Back Pain

2017 ◽  
Vol 26 (5) ◽  
pp. 329-338 ◽  
Author(s):  
Ram Haddas ◽  
Steven F. Sawyer ◽  
Phillip S. Sizer ◽  
Toby Brooks ◽  
Ming-Chien Chyu ◽  
...  
Keyword(s):  
Back Pain ◽  
Lower Extremity ◽  
Injury Risk ◽  
Outcome Measure ◽  
Reaction Force ◽  
Initial Contact ◽  
Vastus Medialis ◽  
Semitendinosus Muscle ◽  
Main Outcome Measure ◽  
Spine Stabilization

Introduction:Recurrent lower back pain (rLBP) and neuromuscular fatigue are independently thought to increase the risk of lower extremity (LE) injury. Volitional preemptive abdominal contraction (VPAC) is thought to improve lumbar spine and pelvis control in individuals with rLBP. The effects of VPAC on fatigued landing performance in individuals with rLBP are unknown.Objectives:To determine the effects of VPAC and LE fatigue on landing performance in a rLBP population.Design:Cross-sectional pretest-posttest cohort control design.Setting:A clinical biomechanics laboratory.Subjects:32 rLBP (age 21.2 ± 2.7 y) but without current symptoms and 33 healthy (age 20.9 ± 2.3 y) subjects.Intervention(s):(i) Volitional preemptive abdominal contraction using abdominal bracing and (ii) fatigue using submaximal free-weight squat protocol with 15% body weight until task failure was achieved.Main Outcome Measure(s):Knee and ankle angles, moments, electromyographic measurements from semitendinosus and vastus medialis muscles, and ground reaction force (GRF) were collected during 0.30 m drop-jump landings.Results:The VPAC resulted in significantly earlier muscle onsets across all muscles with and without fatigue in both groups (mean ± SD, 0.063 ± 0.016 s earlier; P ≤ .001). Fatigue significantly delayed semitendinosus muscle onsets (0.033 ± 0.024 s later; P ≤ .001), decreased GRF (P ≤ .001), and altered landing kinematics in a variety of ways. The rLBP group exhibited delayed semitendinosus and vastus medialis muscle onsets (0.031 ± 0.028 s later; P ≤ .001) and 1.8° less knee flexion at initial contact (P ≤ .008).Conclusion:The VPAC decreases some of the detrimental effects of fatigue on landing biomechanics and thus may reduce LE injury risk in a rLBP population.

scholarly journals Change of Direction Biomechanics in a 180-Degree Pivot Turn and the Risk for Noncontact Knee Injuries in Youth Basketball and Floorball Players

2021 ◽  
pp. 036354652110269
Author(s):  
Mari Leppänen ◽  
Jari Parkkari ◽  
Tommi Vasankari ◽  
Sami Äyrämö ◽  
Juha-Pekka Kulmala ◽  
...  
Keyword(s):  
Knee Flexion ◽  
Injury Risk ◽  
Knee Injury ◽  
Reaction Force ◽  
Knee Injuries ◽  
Flexion Angle ◽  
Knee Valgus ◽  
Change Of Direction ◽  
Increased Risk ◽  
Peak Knee

Background: Studies investigating biomechanical risk factors for knee injuries in sport-specific tasks are needed. Purpose: To investigate the association between change of direction (COD) biomechanics in a 180-degree pivot turn and knee injury risk among youth team sport players. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 258 female and male basketball and floorball players (age range, 12-21 years) participated in the baseline COD test and follow-up. Complete data were obtained from 489 player-legs. Injuries, practice, and game exposure were registered for 12 months. The COD test consisted of a quick ball pass before and after a high-speed 180-degree pivot turn on the force plates. The following variables were analyzed: peak vertical ground-reaction force (N/kg); peak trunk lateral flexion angle (degree); peak knee flexion angle (degree); peak knee valgus angle (degree); peak knee flexion moment (N·m/kg); peak knee abduction moment (N·m/kg); and peak knee internal and external rotation moments (N·m/kg). Legs were analyzed separately and the mean of 3 trials was used in the analysis. Main outcome measure was a new acute noncontact knee injury. Results: A total of 18 new noncontact knee injuries were registered (0.3 injuries/1000 hours of exposure). Female players sustained 14 knee injuries and male players 4. A higher rate of knee injuries was observed in female players compared with male players (incidence rate ratio, 6.2; 95% CI, 2.1-21.7). Of all knee injuries, 8 were anterior cruciate ligament (ACL) injuries, all in female players. Female players displayed significantly larger peak knee valgus angles compared with male players (mean for female and male players, respectively: 13.9°± 9.4° and 2.0°± 8.5°). No significant associations between biomechanical variables and knee injury risk were found. Conclusion: Female players were at increased risk of knee and ACL injury compared with male players. Female players performed the 180-degree pivot turn with significantly larger knee valgus compared with male players. However, none of the investigated variables was associated with knee injury risk in youth basketball and floorball players.

Effect of Sex and Ankle Brace Design on Knee Biomechanics During a Single-Leg Cut

2020 ◽  
Vol 48 (6) ◽  
pp. 1496-1504
Author(s):  
Wyatt D. Ihmels ◽  
Kayla D. Seymore ◽  
Tyler N. Brown
Keyword(s):  
Internal Rotation ◽  
Repeated Measures ◽  
Injury Risk ◽  
Abduction Angle ◽  
Knee Biomechanics ◽  
Ankle Inversion ◽  
Ankle Brace ◽  
Peak Knee ◽  
Knee Abduction ◽  
And Control

Background: Despite success at preventing ankle sprain, prophylactics that restrict ankle plantarflexion motion may produce deleterious knee biomechanics and increase injury risk. Purpose: To determine if ankle prophylactics that restrict plantar- and dorsiflexion motion produce changes in knee biomechanics during a single-leg cut and whether those changes differ between sexes. Study Design: Controlled laboratory study. Methods: A total of 17 male and 17 female participants performed a single-leg cut with 4 conditions: Ankle Roll Guard (ARG), lace-up brace, nonelastic tape, and an unbraced control. Peak stance knee flexion, abduction, and internal rotation joint angle and moment; total knee reaction moment (TKM) and its components (sagittal, frontal, and transverse); and ankle plantarflexion and inversion range of motion (ROM) and peak stance joint moments were tested with a repeated measures analysis of variance to determine the main effect and interaction of condition and sex. Results: Brace and tape restricted plantarflexion ROM as compared with ARG and control (all P < .001). With the brace, women had increased peak knee abduction angle versus ARG ( P = .012) and control ( P = .009), and men had decreased peak knee internal rotation moment as compared with ARG ( P = .032), control ( P = .006), and tape ( P = .003). Although the restrictive tape decreased inversion ROM when compared with ARG ( P = .004) and brace ( P = .017), it did not change knee biomechanics. Neither brace nor tape produced significant changes in TKM or components, yet sagittal TKM increased with ARG versus control ( P = .016). Women exhibited less ankle inversion ROM ( P = .003) and moment ( P = .049) than men, while men exhibited significantly greater frontal TKM ( P = .022) and knee internal rotation moment with the ARG ( P = .029), control ( P = .007), and tape ( P = .016). Conclusion: Prophylactics that restrict ankle plantarflexion motion may elicit knee biomechanical changes during a single-leg cut, but these changes may depend on prophylactic design and user’s sex and may increase women’s injury risk. Clinical Relevance: Sex-specific ankle prophylactic designs may be warranted to reduce knee injury during sports.

Jumping in Ballet: A Systematic Review of Kinetic and Kinematic Parameters

2021 ◽  
Vol 36 (2) ◽  
pp. 108-128
Author(s):  
Adam Mattiussi ◽  
Joseph W Shaw ◽  
Derrick D Brown ◽  
Phil Price ◽  
Daniel D Cohen ◽  
...  
Keyword(s):  
Systematic Review ◽  
Skill Acquisition ◽  
Injury Risk ◽  
Sagittal Plane ◽  
Reaction Force ◽  
Initial Contact ◽  
Limited Evidence ◽  
Vertical Ground Reaction Force ◽  
Ballet Dancers ◽  
Plane Joint

AIMS: Understanding the biomechanics of jumping in ballet dancers provides an opportunity to optimize performance and mitigate injury risk. This systematic review aimed to summarize research investigating kinetics and kinematics of jumping in ballet dancers. METHODS: PubMed (MEDLINE), SPORTDiscus, and Web of Science were systematically searched for studies published before December 2020. Studies were required to investigate dancers specializing in ballet, assess kinetics or kinematics during take-off or landing, and be published in English. RESULTS: A total of 3,781 articles were identified, of which 29 met the inclusion criteria. Seven studies investigated take-off (kinetics: n = 6; kinematics: n = 4) and 23 studies investigated landing (kinetics: n = 19; kinematics: n = 12). Included articles were categorized into six themes: Activity Type (n = 10), Environment and Equipment (n = 10), Demographics (n = 8), Physical Characteristics (n = 3), Injury Status (n = 2), and Skill Acquisition and Motor Control (n = 1). Peak landing vertical ground reaction force (1.4 x 9.6 times body weight) was most commonly reported. Limited evidence suggests greater ankle involvement during the take-off of ballet jumps compared to countermovement jumps. There is also limited evidence indicating greater sagittal plane joint excursions upon landing in ballet dancers compared to non-dancers, primarily through a more extended lower extremity at initial contact. Only 4 articles investigated male ballet dancers, which is a notable gap in the literature. CONCLUSIONS: The findings of this review can be used by dance science and medicine practitioners to improve their understanding of jumping in ballet dancers.

Does Chronic Ankle Instability Influence Knee Biomechanics of Females during Inverted Surface Landings?

2018 ◽  
Vol 39 (13) ◽  
pp. 1009-1017 ◽  
Author(s):  
Yumeng Li ◽  
Jupil Ko ◽  
Marika Walker ◽  
Cathleen Brown ◽  
Julianne Schmidt ◽  
...  
Keyword(s):  
Internal Rotation ◽  
Knee Flexion ◽  
Sagittal Plane ◽  
Ankle Instability ◽  
Knee Extension ◽  
Chronic Ankle Instability ◽  
Initial Contact ◽  
Knee Biomechanics ◽  
Peak Knee ◽  
Eccentric Work

AbstractThe primary purpose of the study was to determine whether atypical knee biomechanics are exhibited during landing on an inverted surface. A seven-camera motion analysis system and two force plates were used to collect lower extremity biomechanics from two groups of female participants: 21 subjects with chronic ankle instability (CAI) and 21 with pair-matched controls. Subjects performed ten landings onto inverted and flat platforms on the CAI/matched and non-test limbs, respectively. Knee and ankle joint angles, joint angular displacements, joint moments and eccentric work were calculated during the landing phase and/or at the initial contact. Paired t-tests were used to compare between-group differences (p<0.05). We observed that CAI group displayed a significantly increased knee flexion angle, knee flexion displacement, peak knee extension moment and internal rotation moment, and eccentric work in the sagittal plane, possibly due to altered ankle biomechanics. Participants with CAI employed some compensatory strategy to improve their ankle and postural stability during landing onto the tilted surface. The increased knee extension and internal rotation moments of CAI participants could potentially result in a greater ACL loading. In future studies, it may be worthwhile to measure or estimate the ACL loading to confirm whether CAI could relate to the mechanism of ACL injury.

scholarly journals Leg Stiffness and Vertical Stiffness of Habitual Forefoot and Rearfoot Strikers during Running

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Lulu Yin ◽  
Xiaoyue Hu ◽  
Zhangqi Lai ◽  
Kun Liu ◽  
Lin Wang
Keyword(s):  
Injury Risk ◽  
Loading Rate ◽  
Reaction Force ◽  
Running Economy ◽  
Initial Contact ◽  
Vertical Ground Reaction Force ◽  
Vertical Stiffness ◽  
Impact Peak ◽  
Leg Stiffness ◽  
Foot Strike

Foot strike patterns influence the running efficiency and may be an injury risk. However, differences in the leg stiffness between runners with habitual forefoot (hFFS) and habitual rearfoot (hRFS) strike patterns remain unclear. This study aimed at determining the differences in the stiffness, associated loading rate, and kinematic performance between runners with hFFS and hRFS during running. Kinematic and kinetic data were collected amongst 39 runners with hFFS and 39 runners with hRFS running at speed of 3.3 m/s, leg stiffness (Kleg), and vertical stiffness (Kvert), and impact loads were calculated. Results found that runners with hFFS had greater Kleg ( P = 0.010 , Cohe n ’ s   d = 0.60 ), greater peak vertical ground reaction force (vGRF) ( P = 0.040 , Cohe n ’ s   d = 0.47 ), shorter contact time( t c ) ( P < 0.001 , Cohe n ’ s   d = 0.85 ), and smaller maximum leg compression ( Δ L ) ( P = 0.002 , Cohe n ’ s   d = 0.72 ) compared with their hRFS counterparts. Runners with hFFS had lower impact peak (IP) ( P < 0.001 , Cohe n ’ s   d = 1.65 ), vertical average loading rate (VALR) ( P < 0.001 , Cohe n ’ s   d = 1.20 ), and vertical instantaneous loading rate (VILR) ( P < 0.001 , Cohe n ’ s   d = 1.14 ) compared with runners with hRFS. Runners with hFFS landed with a plantar flexed ankle, whereas runners with hRFS landed with a dorsiflexed ankle ( P < 0.001 , Cohe n ’ s   d = 3.35 ). Runners with hFFS also exhibited more flexed hip ( P = 0.020 , Cohe n ’ s   d = 0.61 ) and knee ( P < 0.001 , Cohe n ’ s   d = 1.15 ) than runners with hRFS at initial contact. These results might indicate that runners with hFFS were associated with better running economy through the transmission of elastic energy.

Sign in / Sign up

Export Citation Format

Share Document