scholarly journals Impact of Engaging the Nonthrowing Arm on Maximal Ball Velocity From an Overhand Throw With Both the Dominant and Nondominant Arms: A Pilot Study

2021 ◽  
pp. 1-18
Author(s):  
Alanna Weisberg ◽  
Hyun Suk Lee ◽  
Tak Fung ◽  
Larry Katz
Keyword(s):  
The Body ◽  
Whole Body ◽  
Camera Motion ◽  
Ball Speed ◽  
Kinematic Data ◽  
Overhand Throw ◽  
Ball Velocity ◽  
Analysis System ◽  
The Impact ◽  
Camera Motion Analysis

The overhand throw is a complex whole-body motor skill that is fundamental to many sports and activities. When throwing properly, the momentum generated to complete the movement begins in the lower body and transfers through the trunk to the throwing arm. This proof-of-concept study’s primary purpose was to evaluate the impact of the nonthrowing arm on the ball speed during an overhand throw with both the dominant and nondominant arms. Eighteen participants (age: 20.20 ± 2.90 years, nine women) were divided into two intervention groups: a pulling group taught to engage the nonthrowing arm through a pull toward the body and a nonpulling group taught the overhand throw using a component-based physical education curriculum. Each participant completed 12 total throws, six for each side (dominant and nondominant arm). Ball speed and kinematic data were collected using an eight-camera motion analysis system and were assessed using a pre–post study design. The two groups showed significant improvements pre–post when throwing with both the dominant and nondominant arms. Based on effect size comparisons, engaging the nonthrowing arm makes a meaningful difference in maximal ball velocity.

scholarly journals Effect of Leg Dominance on The Center-of-Mass Kinematics During an Inside-of-the-Foot Kick in Amateur Soccer Players

2014 ◽  
Vol 42 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Matteo Zago ◽  
Andrea Francesco Motta ◽  
Andrea Mapelli ◽  
Isabella Annoni ◽  
Christel Galvani ◽  
...  
Keyword(s):  
Body Movement ◽  
Center Of Mass ◽  
Three Dimensional ◽  
The Body ◽  
Soccer Players ◽  
Upper Body ◽  
Whole Body ◽  
Movement Velocity ◽  
Ground Support ◽  
Analysis System

Abstract Soccer kicking kinematics has received wide interest in literature. However, while the instep-kick has been broadly studied, only few researchers investigated the inside-of-the-foot kick, which is one of the most frequently performed techniques during games. In particular, little knowledge is available about differences in kinematics when kicking with the preferred and non-preferred leg. A motion analysis system recorded the three-dimensional coordinates of reflective markers placed upon the body of nine amateur soccer players (23.0 ± 2.1 years, BMI 22.2 ± 2.6 kg/m2), who performed 30 pass-kicks each, 15 with the preferred and 15 with the non-preferred leg. We investigated skill kinematics while maintaining a perspective on the complete picture of movement, looking for laterality related differences. The main focus was laid on: anatomical angles, contribution of upper limbs in kick biomechanics, kinematics of the body Center of Mass (CoM), which describes the whole body movement and is related to balance and stability. When kicking with the preferred leg, CoM displacement during the ground-support phase was 13% higher (p<0.001), normalized CoM height was 1.3% lower (p<0.001) and CoM velocity 10% higher (p<0.01); foot and shank velocities were about 5% higher (p<0.01); arms were more abducted (p<0.01); shoulders were rotated more towards the target (p<0.01, 6° mean orientation difference). We concluded that differences in motor control between preferred and non-preferred leg kicks exist, particularly in the movement velocity and upper body kinematics. Coaches can use these results to provide effective instructions to players in the learning process, moving their focus on kicking speed and upper body behavior

Just Skin and Bones: The Longing for Wholeness of the Body in the Book of Job

2008 ◽  
Vol 58 (3) ◽  
pp. 287-299 ◽  
Author(s):  
Alec Basson
Keyword(s):  
Social Relations ◽  
The Body ◽  
Whole Body ◽  
Book Of Job ◽  
Personal Loss ◽  
Ancient Israel ◽  
Social Unity ◽  
Ideal Body Image ◽  
Ideal Body ◽  
The Impact

AbstractThe book of Job recounts the story of an individual who grapples with the enigma of suffering. In addition to his personal loss, the supplicant's body also comes under attack. Furthermore, the physical distress experienced by Job is exacerbated by the attitude of his kinsmen. His disintegrated body has lead to severed social relations. Given the fact that the body mediates the plaintiff's involvement in society and represented social unity in ancient Israel, Job longs for a whole body as the ideal body image. The ancient Israelites only regarded the whole body as pure, real and acceptable. This contribution argues that to appreciate fully the allusions to bodily degeneration in the book of Job, the importance of wholeness of the physical body in ancient Israel and the impact it had on the socio-religious structure should be taken into account.

Optimal Shoulder Abduction Angles during Baseball Pitching from Maximal Wrist Velocity and Minimal Kinetics Viewpoints

2002 ◽  
Vol 18 (4) ◽  
pp. 306-320 ◽  
Author(s):  
Tomoyuki Matsuo ◽  
Tsuyoshi Matsumoto ◽  
Yoshiyuki Mochizuki ◽  
Yoshihiro Takada ◽  
Kenji Saito
Keyword(s):  
High Speed ◽  
Abduction Angle ◽  
Shoulder Abduction ◽  
Ball Speed ◽  
Kinematic Data ◽  
Reasonable Approximation ◽  
Ball Velocity ◽  
Baseball Coaches

Baseball coaches train pitchers to keep their shoulder abduction at 90º during delivery, because this angle is believed to maximize ball speed and reduce the stress on the throwing arm. In fact, however, the shoulder abduction angle for some pitchers, including professional pitchers, deviates from 90º. There likely are reasons for such deviation. The purposes of this study, therefore, were to investigate the effects of shoulder abduction angle on ball velocity and on the injury-related joint kinetic variable, and to determine why the shoulder abduction angle varies among pitchers. Eleven professional pitchers were videotaped with two high-speed cameras. The resulting kinematic data were used to simulate several pitching motions by varying the shoulder abduction angle from the actual angle. Maximum wrist velocity was used as a reasonable approximation of ball velocity. Elbow varus torque was used as a kinetic variable. The square torque for the throwing arm and torque change for the throwing arm were used to investigate the cause of the variation. It was found that the shoulder abduction angle of 90º did not always maximize wrist velocity nor minimize elbow varus torque. The actual shoulder abduction angle for each pitcher was highly consistent with the angle that minimized both square torque and torque change. The results suggested that the proficient throwers in this study moved their pitching arm so as to minimize mechanical cost while at the same time optimizing performance.

scholarly journals ANALYSIS OF TRUNK POWER AND JOINT STRESSES BETWEEN PROFESSIONAL AND COLLEGIATE PITCHERS

2021 ◽  
Vol 57 (2) ◽  
pp. 121-127
Author(s):  
Maxwell L. Albiero ◽  
◽  
Cody Dziuk ◽  
Janelle A. Cross
Keyword(s):  
External Rotation ◽  
Camera Motion ◽  
Joint Stress ◽  
Joint Torques ◽  
Dynamic Motion ◽  
Shoulder External Rotation ◽  
Analysis System ◽  
Set Up ◽  
3D Software ◽  
Camera Motion Analysis

The dynamic motion of a baseball pitch generates high elbow and shoulder torques that can result in injury. Previous research has noted the importance of properly transferring energy from the lower extremities through the throwing arm to decrease joint stress. The goal of this study was to compare segmental powers between two levels of pitchers at various moments throughout the pitching cycle and observe their influence on upper extremity torques. Thirteen professional and thirteen collegiate pitchers participated in this study. Forty-seven reflective markers were attached to the subjects at specific landmarks. An 8-camera motion analysis system was set up surrounding an artificial pitching mound, where participants threw 10 fastballs. Data were exported and processed using Visual 3D software. Welch’s T-tests compared the means between groups with a significance set at p < 0.05. Professional pitchers were found to have significantly greater torso power at foot contact, maximum shoulder external rotation, ball release, and overall peak torso power. They also demonstrated significantly greater pitch velocity. Professional pitchers generated similar elbow varus torque and shoulder internal rotation torque compared to collegiate pitchers. These findings suggest professional pitchers more effectively use torso power to help increase pitch speed without increasing overall joint torques.

scholarly journals O processo de fadiga pode alterar a estratégia motora de velocidade de golpes no karate: um estudo de caso

2016 ◽  
Vol 85 (3) ◽  
Author(s):  
Keith Sato Urbinati ◽  
Matheus Aguiar ◽  
Juarez Trancoso ◽  
Caluê Papcke ◽  
Percy Nohama ◽  
...  
Keyword(s):  
Biomechanical Model ◽  
Left Knee ◽  
Black Belt ◽  
South American ◽  
Camera Motion ◽  
Vo2 Max ◽  
Motor Strategy ◽  
Analysis System ◽  
Camera Motion Analysis ◽  
Motor Strategies

Introdução: Devido às novas exigências nas regras competitivas com maiores pontuações, o karate vem se tornando um esporte com altas demandas da variável velocidade. Dentre diversos fatores que podem afetar a velocidade de golpes, o processo de fadiga exaustão é uma importante variável interveniente. Logo, como ocorre o controle motor para a manutenção de velocidade de golpes em situação de fatigabilidade?Objetivo: Identificar as estratégias motoras na manutenção de velocidade do gyako zuki no processo de fadiga.Métodos: Foi avaliado o atual campeão sul-americano da categoria -78 kg, sub 21 do sistema World Karate Federation (WKF). O atleta prática karate por 7 anos, é faixa preta, nível internacional, com 78 kg, 1,82m, 14,4% de gordura, VO2 máx = 55 kg.ml-1.min-1. O atleta realizou um protocolo de carga progressiva denominado Karate Specific Aerobic Test (KSAT) até a exaustão. Para o modelo biomecânico foi utilizado um sistema de análise de movimento de seis câmeras (Sistema Vicon).Resultados: As diferentes contribuições de velocidade de segmentos para a manutenção de vP (velocidade de pico) do gyako zuki ocorre uma vez que protocolos de fadiga comumente atribuem adaptações funcionais para superar o efeito da fadiga e continuar executando a ação técnica da ‘melhor’ forma possível.Conclusão: A principal estratégia motora adotada no processo de fadiga é a diminuição do deslocamento de tornozelo e joelho esquerdos à frente, o que diminui a vP do gyako zuki. O deslocamento do segmento de quadril ocorre em situação de homeostase e não necessariamente em situação de fadiga.The process of fatigue can change the motor strategy in velocities of strokes in karate: a case studyIntroduction: Because of the new requirements in the competitive rules with higher scores, karate has become a sport with high demands of speed. Among many factors that can affect the speed of strokes, the process of fatigue exhaustion is an important intervening variable. How the motor control for maintaining speed in strokes fatigability situation?Objective: Identify the motor strategies in maintaining gyako zuki speed in the fatigue process.Methods: We evaluated the current South American champion of the category -78 kg, under 21 years of age, World Karate Federation system (WKF). The karate athlete practice for 7 years, is a black belt, internationally, with 78 kg, 1.82m, 14.4% fat, VO2 max = 55 kg.ml -1 .min -1. The athlete made a progressive load protocol called Karate Specific Aerobic Test (KSAT) until exhaustion. For biomechanical model was used a six camera motion analysis system (Vicon system).Results: Different contributions segments speed to maintain Vp (peak velocity) gyako zuki occurs because fatigue protocols commonly assigned functional adaptations to overcome the effects of fatigue and continue running the technical action as 'better' as possible.Conclusion: The main motor strategy adopted in the fatigue process is the reduction of ankle dislocation and left knee forwarding, which reduces the vP of gyako zuki. The displacement of the hip segment occurs in homeostasis position and not necessarily by fatigue condition.

scholarly journals Interpersonal synchrony feels good but impedes self-regulation of affect

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Laura Galbusera ◽  
Michael T. M. Finn ◽  
Wolfgang Tschacher ◽  
Miriam Kyselo
Keyword(s):  
Positive Affect ◽  
Self Regulation ◽  
The Body ◽  
Whole Body ◽  
Beneficial Effects ◽  
Interpersonal Synchrony ◽  
The Social ◽  
Widespread Belief ◽  
The Stability ◽  
The Impact

Abstract The social benefits of interpersonal synchrony are widely recognized. Yet, little is known about its impact on the self. According to enactive cognitive science, the human self for its stability and regulation needs to balance social attunement with disengagement from others. Too much interpersonal synchrony is considered detrimental for a person’s ability to self-regulate. In this study, 66 adults took part in the Body-Conversation Task (BCT), a dyadic movement task promoting spontaneous social interaction. Using whole-body behavioural imaging, we investigated the simultaneous impact of interpersonal synchrony (between persons) and intrapersonal synchrony (within a person) on positive affect and self-regulation of affect. We hypothesized that interpersonal synchrony’s known tendency to increase positive affect would have a trade-off, decreasing a person’s ability to self-regulate affect. Interpersonal synchrony predicted an increase in positive affect. Consistent with our hypothesis, it simultaneously predicted a weakening in self-regulation of affect. Intrapersonal synchrony, however, tended to oppose these effects. Our findings challenge the widespread belief that harmony with others has only beneficial effects, pointing to the need to better understand the impact of interaction dynamics on the stability and regulation of the human self.

Influence of cross-fit footwear on patellofemoral kinetics during running activities

2017 ◽  
Vol 13 (2) ◽  
pp. 105-111 ◽  
Author(s):  
J.K. Sinclair ◽  
P.J. Taylor ◽  
B. Sant
Keyword(s):  
Repeated Measures ◽  
Camera Motion ◽  
Repeated Measures Anova ◽  
Joint Pathology ◽  
Limb Kinematics ◽  
Analysis System ◽  
Camera Motion Analysis ◽  
Lower Limb Kinematics ◽  
Reduced Risk ◽  
Modelling Approach

The aim of this work was to examine the effects of barefoot, cross-fit, minimalist and conventional footwear on patellofemoral loading during running. Twelve cross-fit athletes ran at 4.0 m/s in each of the four footwear conditions. Lower limb kinematics were collected using an 8 camera motion analysis system and patellofemoral loading was estimated using a mathematical modelling approach. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak patellofemoral force and stress were significantly reduced when running barefoot (force = 3.42 BW & stress = 10.71 MPa) and in minimalist footwear (force = 3.73 BW & stress = 11.64 MPa) compared to conventional (force = 4.12 BW & stress = 12.69 MPa) and cross-fit (force = 3.97 BW & stress = 12.30 MPa) footwear. In addition, the findings also showed that patellofemoral impulse was significantly reduced when running barefoot (0.35 BW·s) and in minimalist footwear (0.36 BW·s) compared to conventional (0.42 BW·s) and cross-fit (0.38 BW·s) footwear. Given the proposed association between patellofemoral loading and patellofemoral disorders, the outcomes from the current investigation suggest that cross-fit athletes who select barefoot and minimalist footwear for their running activities may be at reduced risk from patellofemoral joint pathology in comparison to conventional and cross-fit footwear conditions.

POSTURE CONTROL AND BALANCE DURING TAI CHI CHUAN PUSH HANDS MOVEMENTS IN A FIXED STANCE

2012 ◽  
Vol 12 (05) ◽  
pp. 1250030 ◽  
Author(s):  
LIN-HWA WANG ◽  
KUO-CHENG LO ◽  
FONG-CHIN SU
Keyword(s):  
Tai Chi ◽  
Center Of Pressure ◽  
Center Of Mass ◽  
Reaction Force ◽  
Whole Body ◽  
Expert Group ◽  
Tai Chi Chuan ◽  
Kinematic Data ◽  
Analysis System ◽  
Force Data

The present study investigated the adequacy of the interaction between the center of mass (COM) and the center of pressure (COP) for maintaining dynamic stability during Tai Chi Chuan (TCC) Push Hands movements in a fixed stance. The COM of the whole body and COP were calculated. Four TCC experts, with 10.3 ± 1.7 years' experience in the Push Hands technique, and 4 TCC beginners, with 2.5 ± 1.3 years' Push Hands experience, were recruited. An Expert Vision Eagle motion analysis system collected kinematic data and 4 Kistler force plates collected the ground reaction force data. The expert group of TCC practitioners showed a significantly more vertical (P = 0.001) direction in the neutralizing circle, and significantly larger values for anterior–posterior (A–P) (P = 0.006) and vertical (P = 0.0004) displacement in the enticing circle, than the beginner group. Compared with the beginner group, the expert group demonstrated significantly greater velocity A–P (P = 0.001) and vertical (P = 0.001) COM displacements in the enticing circle. A significant extent main effect (P = 0.0028) was observed for the COPA–P excursion between the expert and beginner groups during Push Hands movements. The greater A–P force generated by both groups during the initiation of the Push Hands cycle probably reflects the more rapid and forward-oriented nature of this movement. The TCC beginners might have difficulties with movement transfers because of disruptions in the temporal sequencing of the forces. Overall, results indicated that the initial experience-related differences in COM transfers are reflected in the Push Hands movement cycle.

Comparison of Foot Pronation and Lower Extremity Rotation in Persons With and Without Patellofemoral Pain

2002 ◽  
Vol 23 (7) ◽  
pp. 634-640 ◽  
Author(s):  
Christopher M. Powers ◽  
Pon-Yo Chen ◽  
Stephen F. Reischl ◽  
Jaquelin Perry
Keyword(s):  
Lower Extremity ◽  
Internal Rotation ◽  
Three Dimensional ◽  
Patellofemoral Pain ◽  
Group Differences ◽  
Camera Motion ◽  
Foot Pronation ◽  
Analysis System ◽  
Camera Motion Analysis ◽  
Female Subjects

Abnormal foot pronation and subsequent rotation of the lower extremity has been hypothesized as being contributory to patellofemoral pain (PFP). The purpose of this study was to test the hypothesis that subjects with PFP would exhibit larger degrees of foot pronation, tibia internal rotation, and femoral internal rotation compared to individuals without PFP. Twenty-four female subjects with a diagnosis of PFP and 17 female subjects without PFP participated. Three-dimensional kinematics of the foot, tibia, and femur segments were recorded during self-selected free-walking trials using a six-camera motion analysis system (VICON). No group differences were found with respect to the magnitude and timing of peak foot pronation and tibia rotation. However, the PFP group demonstrated significantly less femur internal rotation compared the comparison group. These results do not support the hypothesis that individuals with PFP demonstrate excessive foot pronation or tibial internal rotation compared to nonpainful individuals. The finding of decreased internal rotation in the PFP group suggests that this motion may be a compensatory strategy to reduce the quadriceps angle.

scholarly journals The Test-Retest Reliability of Anatomical Co-Ordinate Axes Definition for the Quantification of Lower Extremity Kinematics During Running

2012 ◽  
Vol 35 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Jonathan Sinclair ◽  
Paul John Taylor ◽  
Andrew Greenhalgh ◽  
Christopher James Edmundson ◽  
Darrell Brooks ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Lower Extremities ◽  
Camera Motion ◽  
Anatomical Landmarks ◽  
Kinematic Parameters ◽  
Paired Samples ◽  
Kinematic Analyses ◽  
Analysis System ◽  
Test Retest Reliability ◽  
Camera Motion Analysis

Three-dimensional (3-D) kinematic analyses are used widely in both sport and clinical examinations. However, this procedure depends on reliable palpation of anatomical landmarks and mal-positioning of markers between sessions may result in improperly defined segment co-ordinate system axes which will produce in-consistent joint rotations. This had led some to question the efficacy of this technique. The aim of the current investigation was to assess the reliability of the anatomical frame definition when quantifying 3-D kinematics of the lower extremities during running. Ten participants completed five successful running trials at 4.0 m·s-1 ± 5%. 3-D angular joint kinematics parameters from the hip, knee and ankle were collected using an eight camera motion analysis system. Two static calibration trials were captured. The first (test) was conducted prior to the running trials following which anatomical landmarks were removed. The second was obtained following completion of the running trials where anatomical landmarks were re-positioned (retest). Paired samples t-tests were used to compare 3-D kinematic parameters quantified using the two static trials, and intraclass correlations were employed to examine the similarities between the sagittal, coronal and transverse plane waveforms. The results indicate that no significant (p>0.05) differences were found between test and retest 3-D kinematic parameters and strong (R2≥0.87) correlations were observed between test and retest waveforms. Based on the results obtained from this investigation, it appears that the anatomical co-ordinate axes of the lower extremities can be defined reliably thus confirming the efficacy of studies using this technique.

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