scholarly journals A Correlational Analysis of Shuttlecock Speed Kinematic Determinants in the Badminton Jump Smash

2020 ◽  
Vol 10 (4) ◽  
pp. 1248 ◽  
Author(s):  
Mark King ◽  
Harley Towler ◽  
Romanda Dillon ◽  
Stuart McErlain-Naylor
Keyword(s):  
Wrist Joint ◽  
External Rotation ◽  
Linear Regression Analysis ◽  
Three Dimensional ◽  
Multiple Linear Regression Analysis ◽  
Acceleration Phase ◽  
Phase Duration ◽  
Kinematic Data ◽  
Post Impact ◽  
Maximal Effort

The forehand jump smash is an essential attacking stroke within a badminton player’s repertoire. A key determinate of the stroke’s effectiveness is post-impact shuttlecock speed, and therefore awareness of critical technique factors that impact upon speed is important to players/coaches. Three-dimensional kinematic data of player, racket and shuttlecock were recorded for 18 experienced players performing maximal effort forehand jump smashes. Joint angles and X-factor (transverse plane pelvis-thorax separation) were calculated at key instants: preparation, end of retraction, racket lowest point, turning point and shuttlecock contact. Peak shoulder, elbow, and wrist joint centre linear velocities, phase durations and jump height were also calculated. Correlational analyses were performed with post-impact shuttlecock speed, revealing significant correlations to peak wrist joint centre linear velocity (r = 0.767), acceleration phase duration (r = −0.543), shoulder internal/external rotation angle at shuttlecock contact (r = 0.508) and X-factor at the end of retraction (r = −0.484). Multiple linear regression analysis revealed 43.7% of the variance in shuttlecock speed could be explained by acceleration phase duration and X-factor at the end of retraction, where shorter acceleration phase durations and more negative X-factor at end of retraction caused greater shuttlecock speeds. These results suggest that motions of the proximal segments (shoulder and pelvis–thorax separation) are critical to developing greater distal linear velocities, which subsequently lead to greater post-impact shuttlecock speed.

scholarly journals Cycling kinematics in healthy adults for musculoskeletal rehabilitation guidance

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Haeun Yum ◽  
Hyang Kim ◽  
Taeyong Lee ◽  
Moon Seok Park ◽  
Seung Yeol Lee
Keyword(s):  
Sagittal Plane ◽  
External Rotation ◽  
Age Groups ◽  
Three Dimensional ◽  
Healthy Adults ◽  
Postoperative Rehabilitation ◽  
Kinematic Data ◽  
Average Value ◽  
The Right ◽  
Musculoskeletal Rehabilitation

Abstract Background Stationary cycling is commonly used for postoperative rehabilitation of physical disabilities; however, few studies have focused on the three-dimensional (3D) kinematics of rehabilitation. This study aimed to elucidate the three-dimensional lower limb kinematics of people with healthy musculoskeletal function and the effect of sex and age on kinematics using a controlled bicycle configuration. Methods Thirty-one healthy adults participated in the study. The position of the stationary cycle was standardized using the LeMond method by setting the saddle height to 85.5% of the participant’s inseam. The participants maintained a pedaling rate of 10–12 km/h, and the average value of three successive cycles of the right leg was used for analysis. The pelvis, hip, knee, and ankle joint motions during cycling were evaluated in the sagittal, coronal, and transverse planes. Kinematic data were normalized to 0–100% of the cycling cycle. The Kolmogorov-Smirnov test, Mann-Whitney U test, Kruskal-Wallis test, and k-fold cross-validation were used to analyze the data. Results In the sagittal plane, the cycling ranges of motion (ROMs) were 1.6° (pelvis), 43.9° (hip), 75.2° (knee), and 26.9° (ankle). The coronal plane movement was observed in all joints, and the specific ROMs were 6.6° (knee) and 5.8° (ankle). There was significant internal and external rotation of the hip (ROM: 11.6°), knee (ROM: 6.6°), and ankle (ROM: 10.3°) during cycling. There was no difference in kinematic data of the pelvis, hip, knee, and ankle between the sexes (p = 0.12 to 0.95) and between different age groups (p = 0.11 to 0.96) in all anatomical planes. Conclusions The kinematic results support the view that cycling is highly beneficial for comprehensive musculoskeletal rehabilitation. These results might help clinicians set a target of recovery ROM based on healthy and non-elite individuals and issue suitable guidelines to patients.

A Three-Dimensional Dynamic Analysis of the Quarterback's Throwing Motion in American Football

1995 ◽  
Vol 11 (4) ◽  
pp. 443-459 ◽  
Author(s):  
Gregory S. Rash ◽  
Robert Shapiro
Keyword(s):  
External Rotation ◽  
Three Dimensional ◽  
American Football ◽  
Peak Performance ◽  
Acceleration Phase ◽  
Video Images ◽  
Performance System ◽  
Shoulder External Rotation ◽  
Collegiate Football ◽  
Coordinate Data

Twelve collegiate football quarterbacks were videotaped while performing drop back passes. The video images were digitized using a Peak Performance system, and three-dimensional (3-D) kinematic and kinetic data were calculated from the 3-D coordinate data using standard analytical procedures. The sequential timing of peak shoulder torques in the delivery for the football throw was peak abduction torque prior to the point of maximum shoulder external rotation (MER), peak internal rotation torque just after MER, and peak horizontal adduction torque just prior to release. As anticipated, large medial deviation torques at the elbow were found in the acceleration phase. However, in many cases the quarterbacks demonstrated larger elbow lateral deviation torques during the follow-through than found in the acceleration phase. This paper will describe these and other kinetic results and the kinematic findings observed during the football pass.

scholarly journals Effect of Glenohumeral Internal Rotation Deficit on Shoulder in Baseball Pitchers during Fastball Pitching

2020 ◽  
Vol 17 (21) ◽  
pp. 8211
Author(s):  
Hwai-Ting Lin ◽  
Yu-Chuan Lin ◽  
You-Li Chou ◽  
Hung-Chien Wu ◽  
Rong-Tyai Wang ◽  
...  
Keyword(s):  
Internal Rotation ◽  
Motion Analysis ◽  
External Rotation ◽  
Three Dimensional ◽  
Limited Information ◽  
Shoulder Injury ◽  
Acceleration Phase ◽  
Glenohumeral Internal Rotation Deficit ◽  
Baseball Pitchers ◽  
Analysis System

Previous studies have reported that pitchers with glenohumeral internal rotation deficit (GIRD) may increase the risk of shoulder injury. However, limited information is available regarding the specific effects of GIRD in baseball pitching. The purpose of this study was to investigate whether baseball pitchers with GIRD change their pitching mechanism. Fifteen baseball pitchers with GIRD and 15 pitchers without GIRD were recruited from university or senior high-school teams. A three-dimensional motion analysis system (Eagle System, Motion Analysis Corporation, Santa Rosa, CA, USA) was used to capture the pitching motion while performing fastball pitches. The kinematics and kinetics of the throwing shoulder and trunk were analyzed based on motion captured data. The Mann–Whitney U test was used to test the differences of the analyzed parameters between two groups. At the instant of ball release, the GIRD group showed lower shoulder external rotation and trunk rotation, and larger shoulder horizontal adduction. In addition, the GIRD group exhibited a significantly larger shoulder inferior force in the cocking and acceleration phase, and a significantly larger internal rotation torque in the acceleration phase. The present results suggested that pitchers with GIRD need stretch training to enlarge joint range of motion, and to improve trunk strength and flexibility to alleviate potential problems associated with pitching in GIRD pitchers.

Influence of posterior tibial slope on three-dimensional femorotibial alignment under weightbearing conditions in healthy Japanese elderly people

2021 ◽  
pp. 1-12
Author(s):  
Ryota Katsumi ◽  
Takashi Sato ◽  
Tomoharu Mochizuki ◽  
Satoshi Watanabe ◽  
Osamu Tanifuji ◽  
...  
Keyword(s):  
Sagittal Plane ◽  
External Rotation ◽  
Weight Bearing ◽  
Linear Regression Analysis ◽  
Three Dimensional ◽  
Tibial Slope ◽  
Rotational Alignment ◽  
Posterior Tibial Slope ◽  
Posterior Tibial ◽  
Japanese Elderly

BACKGROUND: Assessment of three-dimensional (3D) femorotibial alignment is essential for successful knee osteoarthritis treatment in the elderly. The complex morphology of the posterior tibial slope (PTS) might have an influence on sagittal and rotational alignment and the positional relationship between the femur and tibia in the anterior–posterior (AP) direction under weight-bearing conditions. OBJECTIVE: This study aimed to clarify the association between the PTS and 3D femorotibial alignment under weight-bearing conditions in healthy Japanese elderly individuals. METHODS: We investigated the 3D femorotibial alignment of 110 lower extremities of 55 healthy individuals (26 women, 29 men, mean age: 70 ± 6 years). Using our previously reported 3D-to-2D image registration technique, we evaluated the 3D hip-knee-ankle angle (3DHKA) in the sagittal plane, rotational alignment, and the distance between the femoral and tibial origins in the AP direction (tibial AP position) as femorotibial alignment parameters under weight-bearing conditions. We assessed the medial and lateral PTS and their angular difference (PTS difference) as PTS parameters. Stepwise multiple linear regression analysis was performed using PTS parameters and other possible confounders (age, sex, height, and weight) as the independent variables and femorotibial alignment parameters as the dependent variable. RESULTS: Weight (𝛽 = 0.393, p < 0.001) and lateral PTS (𝛽 = 0.298, p < 0.001) were the predictors associated with 3DHKA in the sagittal plane. Lateral PTS (𝛽 = 0.304, p = 0.001) was the only predictor associated with the tibial AP position. Sex (𝛽 = −0.282, p = 0.002) and PTS difference (𝛽 = −0.231, p = 0.012) were associated with rotational alignment. CONCLUSIONS: We found that a steeper lateral PTS resulted in a more flexed knee and anterior tibia. The PTS difference was positively correlated with tibial external rotation. Our data could be used as the standard reference for realignment surgery to ensure PTS is appropriately maintained.

scholarly journals Three-dimensional motion analysis of ten common Asian sitting positions in daily living and factors affect range of hip motions

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Phob Ganokroj ◽  
Jirayu Chaowalitwong ◽  
Pichitpol Kerdsomnuek ◽  
Narumol Sudjai ◽  
Pisit Lertwanich ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Motion Analysis ◽  
External Rotation ◽  
Three Dimensional ◽  
Cross Sectional Study ◽  
Flexion Angle ◽  
Abduction Angle ◽  
Female Group ◽  
Cross Sectional ◽  
Kinematic Data

Abstract Background Sitting involves many activities of daily life and requires most motion in the hip joint. Asians have more hip flexion and external rotation motions than Westerners owing to cultural and lifestyle differences. Being aware of the normal range of hip motion is essential in clinical practice. Limited research has focused on the hip motions of common sitting positions. The objective was to determine the hip motions of 10 common sitting positions, and to determine whether gender or being overweight affects the range of hip motions. Methods An experimental cross-sectional study was conducted to determine hip motions by using a standard, three-dimensional, motion-analysis system. Healthy subjects performed 10 sitting positions during 3 trials. All hip-kinematic data were measured on the dominant leg of each participant, except for the right- and left-monk positions (both hips were analyzed). Density plots were constructed and statistical analyses were performed to detect the differences between groups (male and female; non-overweight and overweight). Results The 48 participants comprised 24 males and 24 females. Most were right-leg dominant (45 participants, 93.8%). Of the 22 participants in the overweight group (body mass index ≥23 kg/m2), 18 (75%) were male. Squatting showed the highest flexion angle (99.7°, 47.3°–122°). Cross-legged sitting had the highest abduction angle (28.9°, 9.9°–45.7°) and the largest external rotation angle (62°, 37.6°–81.7°). In the female group, there were trends toward a greater flexion angle (4 out of 10 sitting positions) and a smaller abduction angle (6 out of 9 positions), with P values < 0.05. As to body weight, the overweight participants had a smaller flexion angle but a greater abduction angle, with 5 out of 9 positions having a P value < 0.05. Kinematic data of the transverse plane revealed that the heterogeneity of the rotational angles depended on the sitting position. Conclusions This study provided the functional hip motions of common Asian sitting positions. The kinematic data can be utilized in clinical practice as reference values to determine safe positions. Gender and being overweight affected the hip angles in the sagittal and frontal planes. Trial registration Number TCTR20181021004, retrospectively registered at the Thai Clinical Trials Registry (http//:www.clinicaltrials.in.th).

scholarly journals Cycling Kinematics in Healthy Adults for Musculoskeletal Rehabilitation Guidance

2021 ◽  
Author(s):  
Haeun Yum ◽  
Hyang Kim ◽  
Taeyong Lee ◽  
Moon Seok Park ◽  
Seung Yeol Lee
Keyword(s):  
Sagittal Plane ◽  
External Rotation ◽  
Three Dimensional ◽  
Healthy Adults ◽  
Postoperative Rehabilitation ◽  
Kinematic Data ◽  
Average Value ◽  
The Right ◽  
Joint Motions ◽  
Musculoskeletal Rehabilitation

Abstract Background: Stationary cycling is commonly used for postoperative rehabilitation of physical disabilities, but few studies have focused on the three-dimensional (3D) kinematics of rehabilitation. This study aimed to elucidate the three-dimensional lower limb kinematics of musculoskeletally healthy people and the effect of sex and age on kinematics using a controlled bicycle configuration.Methods: Thirty-one healthy adults participated in the study. The stationary cycle positioning was standardized using the LeMond method by setting the saddle height to 85.5% of the participant’s inseam. The participants maintained a pedaling rate of 10–12 km/h, and the average value of three successive cycles of the right leg was used for analysis. The pelvis, hip, knee, and ankle joint motions during cycling were evaluated in the sagittal, coronal, and transverse planes. Kinematic data were normalized to 0–100% of the cycling cycle. The Kolmogorov-Smirnov test, Mann-Whitney U test, Kruskal-Wallis test, and k-fold cross-validation were used to analyze the data.Results: In the sagittal plane, the cycling ranges of motion (ROMs) were 1.6° (pelvis), 43.9° (hip), 75.2° (knee), and 26.9° (ankle). The coronal plane movement was observed in all joints, and the specific ROMs were 6.6° (knee) and 5.8° (ankle). There was significant internal and external rotation of the hip (ROM: 11.6°), knee (ROM: 6.6°), and ankle (ROM: 10.3°) during cycling. There was no difference in kinematic data of the pelvis, hip, knee, and ankle between sexes (p = 0.12 to 0.95) and among ages (p = 0.11 to 0.96) in all anatomical planes.Conclusions: The kinematic results support the assertion that cycling is highly recommended for comprehensive musculoskeletal rehabilitation. These results may help clinicians choose a target recovery ROM based on healthy and non-elite individuals and issue suitable guidelines to patients.

scholarly journals Motion Analysis Focusing on Rotational Movements of Professional Female Baseball Pitchers: Comparison with Male University Baseball Pitchers

2021 ◽  
Vol 18 (24) ◽  
pp. 13342
Author(s):  
Yoshikazu Azuma ◽  
Tomoyuki Matsui ◽  
Machiko Hiramoto ◽  
Ruo Hashimoto ◽  
Kanta Matsuzawa ◽  
...  
Keyword(s):  
Motion Analysis ◽  
External Rotation ◽  
Three Dimensional ◽  
Lateral Side ◽  
Kinematic Data ◽  
Ball Release ◽  
Rotation Phase ◽  
Baseball Pitchers ◽  
Analysis System ◽  
Throwing Motion

Purpose: The purpose of this study was to compare pitching motion of the professional female baseball pitchers with the male university baseball pitchers focused on the pelvic and thoracic movements. Subjects and methods: The participants were 15 healthy professional female baseball pitchers (11 right-handers and 4 left-handers; age, 21.7 ± 3.2 years; height, 162.5 ± 5.1 cm; weight, 59.0 ± 6.6 kg) and 14 healthy male university baseball pitchers (12 right-handers and 2 left-handers; age, 19.9 ± 0.8 years; height, 176.4 ± 3.0 cm; body mass, 73.1 ± 3.0 kg). Throwing motion was captured by three-dimensional motion analysis system. Kinematic data of the lead hip, pelvis, thorax, and dominant shoulder were collected and the joint angle at maximum external rotation phase and ball release phase were compared. Results: The female baseball pitchers rotated pelvis and thorax more than the male at the maximum external rotation phase and ball release phase (p < 0.05). At the same, the pelvis and thorax of the female baseball pitchers were tilted significantly closer to horizontal plane than the male (p < 0.05). The pelvis and thorax of the male baseball pitchers was tilted to non-dominant lateral side. Conclusions: The results of this study indicate that the pelvic and thoracic movements of the professional female baseball pitchers was different from male university pitchers.

scholarly journals Numerical investigation of reinforced-concrete beam-column joints retrofitted using external superelastic shape memory alloy bars

2021 ◽  
Vol 8 (5) ◽  
pp. 716-738
Author(s):  
Yamen Ibrahim Elbahy ◽  
◽  
Maged A. Youssef ◽  
M. Meshaly ◽  
◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Shape Memory ◽  
Parametric Study ◽  
Linear Regression Analysis ◽  
Three Dimensional ◽  
Element Model ◽  
Multiple Linear Regression Analysis ◽  
Reinforced Concrete Beam ◽  
Rc Structures ◽  
Three Dimensional Finite Element

<abstract> <p>The unique properties of Shape Memory Alloys (SMAs) have motivated researchers to use them as primary reinforcement in reinforced concrete (RC) structures. In this study, the applicability of using external unbonded SMA bars to retrofit RC beam-column joints (BCJs) is investigated. A three-dimensional finite element model, which simulates the suggested retrofitting technique, is first developed, and validated using ABAQUS software. The model is then further simplified and utilized to conduct a parametric study to investigate the behaviour of SMA retrofitted RC BCJs. Results of the parametric study are used to perform multiple linear regression analysis. Simple equations, which can be used to calculate the length and amount of SMA bars required to retrofit a RC BCJ, are then developed.</p> </abstract>

scholarly journals Three-dimensional motion analysis of hip motions in ten common Asian sitting positions in daily living. Do gender and being overweight affect the range of hip motions?

2021 ◽  
Author(s):  
Phob Ganokroj ◽  
Jirayu Chaowalitwong ◽  
Pichitpol Kerdsomneuk ◽  
Narumol Sudjai ◽  
Pisit Lertwanich ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Motion Analysis ◽  
External Rotation ◽  
Three Dimensional ◽  
Cross Sectional Study ◽  
Flexion Angle ◽  
Abduction Angle ◽  
Female Group ◽  
Cross Sectional ◽  
Kinematic Data

Abstract Background Sitting involves many activities of daily life and requires most motion in the hip joint. Asians have more hip flexion and external rotation motions than Westerners owing to cultural and lifestyle differences. Being aware of the normal range of hip motion is essential in clinical practice. Limited research has focused on the hip motions of common sitting positions. The objective was to determine the hip motions of 10 common sitting positions, and to determine whether gender or being overweight affects the range of hip motions.Methods An experimental cross-sectional study was conducted to determine hip motions by using a standard, three-dimensional, motion-analysis system. Healthy subjects performed 10 sitting positions during 3 trials. All hip-kinematic data were measured on the dominant leg of each participant, except for the right- and left-monk positions (both hips were analyzed). Density plots were constructed and statistical analyses were performed to detect the differences between groups (male and female; non-overweight and overweight).Results The 48 participants comprised 24 males and 24 females. Most were right-leg dominant (45 participants; 93.8%). Of the 22 participants in the overweight group (body mass index ≥ 23 kg/m2), 18 (75%) were male. Squatting showed the highest flexion angle (99.7º; 47.3º–122º). Cross-legged sitting had the highest abduction angle (28.9º; 9.9º–45.7º) and the largest external rotation angle (62º; 37.6º–81.7º). In the female group, there were trends toward a greater flexion angle (4 out of 10 sitting positions) and a smaller abduction angle (6 out of 9 positions), with P values < 0.05. As to body weight, the overweight participants had a smaller flexion angle but a greater abduction angle, with 5 out of 9 positions having a P value < 0.05. Kinematic data of the transverse plane revealed that the heterogeneity of the rotational angles depended on the sitting position.Conclusions This study provided the functional hip motions of common Asian sitting positions. The kinematic data can be utilized in clinical practice as reference values to determine safe positions. Gender and being overweight affected the hip angles in the sagittal and frontal planes.Trial registration: Number TCTR20181021004, retrospectively registered at the Thai Clinical Trials Registry (http://www. clinicaltrials.in.th).

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