scholarly journals Difference analysis of long drive swing mechanical movement towards ball velocity based on analysis kinematics approach between skill and unskill golf player

2019 ◽  
Vol 5 (1) ◽  
pp. 41
Author(s):  
Agus Rusdiana ◽  
Hadi Sartono ◽  
Dede Rohmat Nurjaya ◽  
Angga M Syahid
Keyword(s):  
Elbow Joint ◽  
Knee Flexion ◽  
Kinematics Analysis ◽  
Difference Analysis ◽  
Lateral Band ◽  
Ball Velocity ◽  
Hip Rotation ◽  
Mechanical Movement

Tujuan penelitian ini adalah ingin mengetahui perbedaan long drive swing mechanical movement terhadap ball velocity berbasis pendekatan kinematics analysis antara skill dan unskill golf player. Adapun Analisis kinematik terdiri dari: trunk forword tilt, club stick velocity, knee flexion, wrist hinge at the top, leading arm angle, lateral band, hip rotation dan shoulder rotation. Metode yang digunakan dalam penelitian ini adalah metode deskriptif kuantitatif, sedangkan teknik analisis data menggunakan analisis uji perbedaan rata-rata. Sampel dalam penelitian ini adalah 2 atlet professional dan 4 atlet amatir di lingkungan Universitas Pendidikan Indonesia UPI Bandung, dengan rata-rata Tinggi Badan 1.63 ± 2.4 m, Berat Badan 72.4 ± 3.6 kg dan Usia 37.4 ± 7.6 tahun. Hasil penelitian ini menunjukan bahwa dari sepuluh variabel kinematika yang dianalisis terdapat empat indikator yang menunjukan hasil perbedaan signfikan pada taraf alpha 0.05 antara lain club speed at impact (t =0.007), lateral band after impact ball (t = 0.006), shoulder rotation (t = 0.005)  dan flexion at elbow joint arm non dominant (t = 0.003).

The Association Among Trunk Rotation, Ball Velocity, and the Elbow Varus Moment in Collegiate-Level Baseball Pitchers

2019 ◽  
Vol 47 (12) ◽  
pp. 2816-2820 ◽  
Author(s):  
Andrew D. Cohen ◽  
Erin J. Garibay ◽  
Matthew J. Solomito
Keyword(s):  
Elbow Joint ◽  
Rotation Angle ◽  
Rotational Velocity ◽  
Trunk Rotation ◽  
Joint Stress ◽  
Trunk Motion ◽  
Ball Release ◽  
Average Maximum ◽  
Ball Velocity ◽  
Baseball Pitchers

Background: The incidence of upper extremity injuries in baseball pitchers is increasing. Over the past decade, research has attempted to elucidate the cause of these injuries, focusing mainly on pitching arm mechanics with little examination of other important segments, such as the trunk. This is surprising, as trunk motion has been shown to have significant effects on pitching mechanics. Purpose: To determine the associations between trunk rotation, ball velocity, and the moments about the elbow joint. Study Design: Descriptive laboratory study. Methods: Data collected using 3-dimensional motion analysis techniques from 99 collegiate pitchers (18.0-24.8 years) were analyzed. A random intercept mixed-effects regression model was used to determine if significant associations existed between trunk rotation and ball velocity or elbow varus moment. Results: Significant associations were found between trunk rotation angle at ball release and elbow varus moment ( P = .019, β = 0.254) as well as ball velocity ( P = .016, β = 0.060). For every 10° increase over the average trunk rotation angle at ball release, the elbow varus moment increased by 2.54 N·m and the ball velocity increased by 0.60 m/s. Additionally, the maximum rotational velocity of the trunk was positively associated with elbow varus moment ( P < .001, β = 0.029) and ball velocity ( P < .001, β = 0.007). For every 100 deg/s increase over the average maximum rotational velocity of the trunk, the elbow varus moment increased by 2.90 N·m and the ball velocity increased by 0.70 m/s. Conclusion: In collegiate pitchers, trunk rotation angle at ball release was significantly associated with ball velocity and elbow varus moment. Also, an increase in maximum rotational velocity of the trunk was significantly associated with an increase in the ball velocity and elbow varus moment. This work demonstrates the importance of trunk mechanics in the kinetic chain of the pitch cycle. Clinical Relevance: Pitching coaches and trainers can use the results to stress the importance of trunk mechanics in pitching, specifically, combining adequate core function with increased trunk rotational velocity in an effort to increase pitching velocity without increasing elbow joint stress.

Design and Simulation of a PAM Based Bionic Elbow Joint

2013 ◽  
Vol 461 ◽  
pp. 589-596
Author(s):  
Li Na Hao ◽  
Chao Qun Xiang ◽  
Yuan Peng ◽  
Xiao Yu Xu ◽  
Qi Long Wang
Keyword(s):  
Power Density ◽  
Elbow Joint ◽  
Density Ratio ◽  
Artificial Muscle ◽  
Forward Kinematics ◽  
Pneumatic Artificial Muscle ◽  
Kinematics Analysis ◽  
Transmission Part ◽  
Structure Scheme ◽  
Simulation Results

A bionic elbow joint driven by motor is lack of flexibility. So a good option is to improve the flexible and power density ratio. This paper has designed a 3-DOF bionic elbow joint based on pneumatic artificial muscle, and the simulation and forward kinematics analysis have been done. The simulation results show that the structure scheme is feasible, and the movement is smooth. This structure can improve the generalization of the bionic joint and then lay a foundation in the serialization and standardization of the transmission part.

Effects of hip rotation on the electromyographic activity of the medial and lateral hamstrings and muscle force

2021 ◽  
pp. 1-7
Author(s):  
Wootaek Lim
Keyword(s):  
Prone Position ◽  
Supine Position ◽  
Knee Flexion ◽  
External Rotation ◽  
Emg Activity ◽  
Electromyographic Activity ◽  
Hamstring Muscles ◽  
Extension Force ◽  
Hip Rotation ◽  
Hip Extension

BACKGROUND: In clinical practice, knee flexion at the prone position for manual muscle testing of hamstrings and hip extension at the supine position for stretching of hamstring muscles are typically proposed. OBJECTIVE: Although different positions have been proposed for different purposes in hamstrings, the understanding of the changing the functional role of hamstrings with position changes is poorly understood. METHODS: The electromyographic (EMG) activity and hip extension force were compared among different postures; hip neutral, internal, and external rotation. EMG and force were measured in prone position during knee flexion and those were additionally measured in supine position during hip extension. In supine position, additional measurements were made in hip neutral, internal and external rotation. RESULTS: Hamstrings showed high EMG activity during knee flexion. Knee flexion force in prone position was significantly decreased at hip extension force in supine position. In supine position, EMG activity was significantly higher in semitendinosus (ST) than biceps femoris (BF) during internal rotation. CONCLUSIONS: It should be noted that bi-articular muscles may have different functional dependencies on the corresponding muscles for each joint. In addition, because the altered alignment of the hamstring muscles that was affected by hip rotation had a significant effect on muscle activity, and hip rotation may be helpful for selective training of medial or lateral hamstrings.

scholarly journals EFFECT OF STATIC ANATOMIC ALIGNMENT ON DYNAMIC LIMB VALGUS DURING SIDE-STEP CUTTING IN UNINJURED ADOLESCENT ATHLETES

2019 ◽  
Vol 7 (3_suppl) ◽  
pp. 2325967119S0002
Author(s):  
Nicole Mueske ◽  
Daniel T. Feifer ◽  
Curtis VandenBerg ◽  
J. Lee Pace ◽  
Mia J. Katzel ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Internal Rotation ◽  
Knee Flexion ◽  
External Rotation ◽  
Acl Injury ◽  
Adolescent Athletes ◽  
Knee Abduction ◽  
Hip Flexion ◽  
Hip Internal Rotation ◽  
Hip Rotation

BACKGROUND Dynamic limb valgus, combining hip adduction and internal rotation with knee abduction posture and moments, has been implicated in ACL injury. However, the contribution of static lower extremity alignment to dynamic limb valgus is unknown. This study assessed the relationships among lower extremity static alignment and dynamic kinematics and kinetics during side-step cutting in uninjured adolescent athletes. METHODS This prospective study included 88 limbs from 44 uninjured athletes aged 8-15 years (mean 12.3, SD 2.3; 19 (44%) female) who were evaluated during an anticipated 45° side-step cut. 3D lower extremity kinematics and kinetics from a custom 6 degree of freedom model were assessed while standing and during the loading phase of the cut from initial contact to peak knee flexion; 2-3 trials per limb were averaged for analysis. Femoral anteversion was measured for each limb with the participant lying prone. Relationships among static and dynamic measures were investigated using correlation and multiple linear regression. RESULTS In terms of static alignment, more static hip internal rotation and more static knee external rotation (tibia external relative to femur) were associated with more internal hip rotation and external knee rotation dynamically during cutting (r=0.34, p=0.001) (Table 1). Static hip adduction was also related to more external hip rotation and less hip flexion dynamically (p=0.24, p=0.02). More static knee abduction, external hip rotation and hip adduction were associated with higher average knee abduction angles during cutting (r=0.25, p=0.02). However, only static external knee rotation was associated with higher dynamic knee abduction moments (r=0.48, p<0.0001) (Figure 1). During cutting, positive associations were observed between hip flexion, knee flexion, and hip internal rotation (r=0.24, p=0.03). Knee adduction angles were related to more hip flexion, internal hip rotation, and knee external rotation (r=0.25, p=0.02). Additionally, lower peak knee flexion was associated with higher peak ground reaction force and more external knee rotation (r=0.24, p=0.02). Both simple correlation and multiple regression analysis indicated that higher knee abduction moments were related dynamically to higher knee abduction angles, greater knee external rotation, higher hip abduction angles, and greater hip internal rotation (R2=0.72, p<0.001). After considering dynamic metrics, no static measure remained significantly related to knee abduction moments. CONCLUSION/SIGNIFICANCE Static knee rotation was the only anatomic alignment measure associated with knee abduction moments during side-step cutting in uninjured adolescent athletes. Knee abduction moments were influenced more by dynamic posture than static alignment. As knee abduction moments have been implicated in ACL injury, this study supports the notion of dynamic limb valgus, specifically increased knee abduction and hip internal rotation, relating to ACL injury. Motion analysis can be used to identify these risky biomechanical patterns, and neuromuscular training can be used to correct them. Since knee abduction moments are primarily determined by dynamic posture, neuromuscular training can be used to reduce these moments and ACL injury risk. [Figure: see text][Table: see text]

scholarly journals Comparison of Joint Kinematics in Transition Running and Isolated Running in Elite Triathletes in Overground Conditions

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4869
Author(s):  
Laura Fraeulin ◽  
Christian Maurer-Grubinger ◽  
Fabian Holzgreve ◽  
David A. Groneberg ◽  
Daniela Ohlendorf
Keyword(s):  
Knee Flexion ◽  
Statistical Parametric Mapping ◽  
Step Length ◽  
Joint Kinematics ◽  
Inertial Motion ◽  
Long Distance ◽  
Kinematic Data ◽  
Warm Up ◽  
Hip Flexion ◽  
Hip Rotation

Triathletes often experience incoordination at the start of a transition run (TR); this is possibly reflected by altered joint kinematics. In this study, the first 20 steps of a run after a warm-up run (WR) and TR (following a 90 min cycling session) of 16 elite, male, long-distance triathletes (31.3 ± 5.4 years old) were compared. Measurements were executed on the competition course of the Ironman Frankfurt in Germany. Pacing and slipstream were provided by a cyclist in front of the runner. Kinematic data of the trunk and leg joints, step length, and step rate were obtained using the MVN Link inertial motion capture system by Xsens. Statistical parametric mapping was used to compare the active leg (AL) and passive leg (PL) phases of the WR and TR. In the TR, more spinal extension (~0.5–1°; p = 0.001) and rotation (~0.2–0.5°; p = 0.001–0.004), increases in hip flexion (~3°; ~65% AL−~55% PL; p = 0.001–0.004), internal hip rotation (~2.5°; AL + ~0–30% PL; p = 0.001–0.024), more knee adduction (~1°; ~80–95% AL; p = 0.001), and complex altered knee flexion patterns (~2–4°; AL + PL; p = 0.001–0.01) occurred. Complex kinematic differences between a WR and a TR were detected. This contributes to a better understanding of the incoordination in transition running.

Kinematics Analysis of Instep Shot in Different Heights

2014 ◽  
Vol 978 ◽  
pp. 106-109
Author(s):  
Pan Li
Keyword(s):  
Test System ◽  
Soccer Players ◽  
Kinematics Analysis ◽  
Biomechanical Test ◽  
Male College ◽  
Ball Velocity ◽  
Ball Trajectory ◽  
Support Leg ◽  
Ball Point ◽  
Kinematics Parameters

Using biomechanical test system to reveal the kinematics parameters of instep shot in different heights in soccer players. Twelve healthy male college students voluntarily participated in this study. After digitizing the recording collected by camera, this study reached the following conclusion that (1) In instep front shot the lower the contact height with ball during kicking, the faster the ball velocity. Therefore, the author put forward a proposal that in order to obtain the faster ball velocity, the kicking ball point should be lower, and (2) the player can control the ball velocity, ball trajectory, and the time of technique by controlling the vertical distance between support leg and ball.

scholarly journals Structure, Sex, and Strength and Knee and Hip Kinematics During Landing

2011 ◽  
Vol 46 (4) ◽  
pp. 376-385 ◽  
Author(s):  
Jennifer S. Howard ◽  
Melisa A. Fazio ◽  
Carl G. Mattacola ◽  
Timothy L. Uhl ◽  
Cale A. Jacobs
Keyword(s):  
Internal Rotation ◽  
Knee Flexion ◽  
External Rotation ◽  
Tracking System ◽  
Three Dimensional ◽  
Medial Knee ◽  
Peak Knee ◽  
Hip Abduction ◽  
Knee Abduction ◽  
Hip Rotation

Context: Researchers have observed that medial knee collapse is a mechanism of knee injury. Lower extremity alignment, sex, and strength have been cited as contributing to landing mechanics. Objective: To determine the relationship among measurements of asymmetry of unilateral hip rotation (AUHR); mobility of the foot, which we described as relative arch deformity (RAD); hip abduction–external rotation strength; sex; and me-dial collapse of the knee during a single-leg jump landing. We hypothesized that AUHR and RAD would be positively correlated with movements often associated with medial collapse of the knee, including hip adduction and internal rotation excursions and knee abduction and rotation excursions. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: Thirty women and 15 men (age = 21 ± 2 years, height = 171.7 ± 9.5 cm, mass = 68.4 ± 9.5 kg) who had no history of surgery or recent injury and who participated in regular physical activity volunteered. Intervention(s): Participants performed 3 double-leg forward jumps with a single-leg landing. Three-dimensional kinematic data were sampled at 100 Hz using an electromagnetic tracking system. We evaluated AUHR and RAD on the preferred leg and evaluated isometric peak hip abductor–external rotation torque. We assessed AUHR by calculating the difference between internal and external hip rotation in the prone position (AUHR = internal rotation – external rotation). We evaluated RAD using the Arch Height Index Measurement System. Correlations and linear regression analyses were used to assess relationships among AUHR, RAD, sex, peak hip abduction–external rotation torque, and kinematic variables for 3-dimensional motion of the hip and knee. Main Outcome Measure(s): The dependent variables were joint angles at contact and joint excursions between contact and peak knee flexion. Results: We found that AUHR was correlated with hip adduction excursion (R = 0.36, P = .02). Asymmetry of unilateral hip rotation, sex, and peak hip abduction–external rotation torque were predictive of knee abduction excursion (adjusted R2 = 0.47, P &lt; .001). Asymmetry of unilateral hip rotation and sex were predictive of knee external rotation excursion (adjusted R2 = 0.23, P = .001). The RAD was correlated with hip adduction at contact (R2 = 0.10, R = 0.32, P = .04) and knee flexion excursion (R2 = 0.11, R = −0.34, P = .03). Conclusions: Asymmetry of unilateral hip rotation, sex, and hip strength were associated with kinematic components of medial knee collapse.

Gluteus Medius Activity during Isometric Closed-Chain Hip Rotation

2002 ◽  
Vol 11 (3) ◽  
pp. 179-188 ◽  
Author(s):  
Randy J. Schmitz ◽  
Bryan L. Riemann ◽  
Timothy Thompson
Keyword(s):  
Knee Flexion ◽  
Gluteus Medius ◽  
Surface Emg ◽  
Upper Body ◽  
Emg Activity ◽  
Forward Movement ◽  
Closed Chain ◽  
Hip Flexion ◽  
Base Of Support ◽  
Hip Rotation

Objective:To determine whether gluteus medius (GM) activity increases in response to isometric closed-chain external hip rotation.Design:Subjects performed single-leg stances in 3 different conditions: 0° knee flexion, 0° hip flexion (C1); 0° knee flexion, 20° hip flexion (C2); and knee flexed 20–30°, 20° hip flexion (C3). Posteriorly directed forces of 8.9 N (F1), 17.8 N (F2), and 26.7 N (F3) were applied at the lateral pelvis of the nonstance side during each condition.Subjects:20 college students.Measurements:Surface EMG RMS amplitude from the GM and kinematic data from the trunk, hip, and knee.Results:Statistical analyses revealed a significant Condition 3 Force interaction and significant increases of EMG activity from C1F1 and C1F2 to C1F3 and from C3F1 to C3F2 and C3F3. F2 and F3 of C2 were significantly less than F2 and F3 of both C1 and C3.Conclusions:GM activity increases in response to isometric, closed-chain, external hip-rotation forces, and forward movement of the upper body with respect to the base of support decreases GM activity.

Legal Update: North Dakota Supreme Court: Third Edition of Guides is “Most Current”

1999 ◽  
Vol 4 (1) ◽  
pp. 6-7
Author(s):  
James J. Mangraviti
Keyword(s):  
Internal Rotation ◽  
External Rotation ◽  
Measurement Techniques ◽  
Fourth Edition ◽  
Hip Motion ◽  
The Difference ◽  
The Right ◽  
Hip Flexion ◽  
Hip Rotation ◽  
Hip Extension

Abstract The accurate measurement of hip motion is critical when one rates impairments of this joint, makes an initial diagnosis, assesses progression over time, and evaluates treatment outcome. The hip permits all motions typical of a ball-and-socket joint. The hip sacrifices some motion but gains stability and strength. Figures 52 to 54 in AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fourth Edition, illustrate techniques for measuring hip flexion, loss of extension, abduction, adduction, and external and internal rotation. Figure 53 in the AMA Guides, Fourth Edition, illustrates neutral, abducted, and adducted positions of the hip and proper alignment of the goniometer arms, and Figure 52 illustrates use of a goniometer to measure flexion of the right hip. In terms of impairment rating, hip extension (at least any beyond neutral) is irrelevant, and the AMA Guides contains no figures describing its measurement. Figure 54, Measuring Internal and External Hip Rotation, demonstrates proper positioning and measurement techniques for rotary movements of this joint. The difference between measured and actual hip rotation probably is minimal and is irrelevant for impairment rating. The normal internal rotation varies from 30° to 40°, and the external rotation ranges from 40° to 60°.

Sign in / Sign up

Export Citation Format

Share Document