Joint and Segment Sequencing and Its Relationship to Ball Velocity and Throwing Arm Kinetics In Professional Pitchers

Author(s):  
Joseph E. Manzi ◽  
Brittany Dowling ◽  
Zhaorui Wang ◽  
Jim R. Lamb ◽  
Emily G. Fry ◽  
...  
Keyword(s):  
2005 ◽  
Vol 17 (4) ◽  
pp. 668-686 ◽  
Author(s):  
Joost C. Dessing ◽  
C. (Lieke) E. Peper ◽  
Daniel Bullock ◽  
Peter J. Beek

The cerebral cortex contains circuitry for continuously computing properties of the environment and one's body, as well as relations among those properties. The success of complex perceptuomotor performances requires integrated, simultaneous use of such relational information. Ball catching is a good example as it involves reaching and grasping of visually pursued objects that move relative to the catcher. Although integrated neural control of catching has received sparse attention in the neuroscience literature, behavioral observations have led to the identification of control principles that may be embodied in the involved neural circuits. Here, we report a catching experiment that refines those principles via a novel manipulation. Visual field motion was used to perturb velocity information about balls traveling on various trajectories relative to a seated catcher, with various initial hand positions. The experiment produced evidence for a continuous, prospective catching strategy, in which hand movements are planned based on gaze-centered ball velocity and ball position information. Such a strategy was implemented in a new neural model, which suggests how position, velocity, and temporal information streams combine to shape catching movements. The model accurately reproduces the main and interaction effects found in the behavioral experiment and provides an interpretation of recently observed target motion-related activity in the motor cortex during interceptive reaching by monkeys. It functionally interprets a broad range of neurobiological and behavioral data, and thus contributes to a unified theory of the neural control of reaching to stationary and moving targets.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Nenad Muškinja ◽  
Matej Rižnar

We examined a design approach for a PID controller for a nonlinear ball and beam system. Main objective of our research was to establish a nonmodel based control system, which would also not be dependent on a specific ball and beam hardware setup. The proposed PID controller setup is based on a cascaded configuration of an inner PID ball velocity control loop and an outer proportional ball position control loop. The effectiveness of the proposed controller setup was first presented in simulation environment in comparison to a hardware dependent PD cascaded controller, along with a more comprehensive study on possible design approach for optimal PID controller parameters in relation to main functionality of the controller setup. Experimental real time control results were then obtained on a laboratory setup of the ball and beam system on which PD cascaded controller could not be applied without parallel system model processing.


Author(s):  
Md. Yeasir Arafat ◽  
Jannatul Ferdaus Rickta ◽  
Fatima Tus Johora Mukta
Keyword(s):  

2021 ◽  
Vol 77 (1) ◽  
pp. 235-244
Author(s):  
Darío Martínez-García ◽  
Ángela Rodríguez-Perea ◽  
Álvaro Huerta-Ojeda ◽  
Daniel Jerez-Mayorga ◽  
Daniel Aguilar-Martínez ◽  
...  

Abstract The purpose of this study was to investigate the acute effect of pre-activation with Variable Intra-Repetition Resistance and isometry on the overhead throwing velocity in handball players. Fourteen female handball players took part in the study (age: 21.2 ± 2.7 years, experience: 10.9 ± 3.5 years). For Post-Activation Potentiation, two pre-activation methods were used: (I) Variable Intra-Repetition Resistance: 1 x 5 maximum repetitions at an initial velocity of 0.6 m·s-1 and a final velocity of 0.9 m·s-1; (II) Isometry: 1 x 5 s of maximum voluntary isometric contraction. Both methods were "standing unilateral bench presses" with the dominant arm, using a functional electromechanical dynamometer. The variable analysed was the mean of the three overhead throws. Ball velocity was measured with a radar (Stalker ATS). The statistical analysis was performed using ANOVA with repeated measures. No significant differences were found for either method (variable resistance intra-repetition: p = 0.194, isometry: p = 0.596). Regarding the individual responses, the analysis showed that 86% of the sample increased throwing velocity with the variable resistance intra-repetition method, while 93% of the sample increased throwing velocity with the isometric method. Both the variable intra-repetition resistance and isometric methods show improvements in ball velocity in female handball players. However, the authors recommend checking individual responses, since the results obtained were influenced by the short rest interval between the pre-activation and the experimental sets.


2015 ◽  
Vol 114 (3) ◽  
pp. 1577-1592 ◽  
Author(s):  
Barbara La Scaleia ◽  
Myrka Zago ◽  
Francesco Lacquaniti

Two control schemes have been hypothesized for the manual interception of fast visual targets. In the model-free on-line control, extrapolation of target motion is based on continuous visual information, without resorting to physical models. In the model-based control, instead, a prior model of target motion predicts the future spatiotemporal trajectory. To distinguish between the two hypotheses in the case of projectile motion, we asked participants to hit a ball that rolled down an incline at 0.2 g and then fell in air at 1 g along a parabola. By varying starting position, ball velocity and trajectory differed between trials. Motion on the incline was always visible, whereas parabolic motion was either visible or occluded. We found that participants were equally successful at hitting the falling ball in both visible and occluded conditions. Moreover, in different trials the intersection points were distributed along the parabolic trajectories of the ball, indicating that subjects were able to extrapolate an extended segment of the target trajectory. Remarkably, this trend was observed even at the very first repetition of movements. These results are consistent with the hypothesis of model-based control, but not with on-line control. Indeed, ball path and speed during the occlusion could not be extrapolated solely from the kinematic information obtained during the preceding visible phase. The only way to extrapolate ball motion correctly during the occlusion was to assume that the ball would fall under gravity and air drag when hidden from view. Such an assumption had to be derived from prior experience.


2016 ◽  
Vol 30 (12) ◽  
pp. 3428-3435 ◽  
Author(s):  
René Schwesig ◽  
Souhail Hermassi ◽  
Herbert Wagner ◽  
David Fischer ◽  
Georg Fieseler ◽  
...  

2019 ◽  
Vol 7 (7_suppl5) ◽  
pp. 2325967119S0036
Author(s):  
Daphne Ling ◽  
Christopher L. Camp ◽  
Brittany Dowling ◽  
Kathryn Mcelheny ◽  
Joshua S. Dines

Objectives: The incidence of shoulder and elbow overuse injury continues to rise in youth baseball players. Several throwing programs designed to reduce stress on the elbow have been described, but most are not evidence-based. The aim of this study was to compare the kinetics and kinematics between mound and flat-ground pitching at two different distances with the goal of developing evidenced-based injury prevention and recovery guidelines for youth throwers. Methods: Fifteen healthy, high school varsity-level baseball pitchers (mean age 16.7 ± 0.7 yrs; height 182.2 ± 6.2 cm; weight 76.0 ± 9.4 kg;) participated in the study. Players were fitted with a motusBASEBALLTM sensor and sleeve (Motus Global, Rockville Centre, NY), which has been shown to have good reliability and correlation with in-laboratory measures. Each pitcher was asked to pitch 5 fastballs to a catcher under each of the 4 conditions: mound at 60.5 ft (regulation distance), flat ground at 60.5 ft, mound at 50.5 ft, and flat ground at 50.5 ft. For each pitch, the sensor recorded arm speed, arm slot, shoulder rotation, and elbow varus torque. Ball velocity was tracked with a radar gun (Stalker Radar, Richardson, TX). Linear mixed-effects models were used to account for both within and between-subject variability. A multivariable model was used to evaluate the association of mound pitching (vs flat ground), distance (50.5 vs 60.5 ft), and their interaction on each of the following outcomes: arm speed, arm slot, shoulder rotation, elbow varus torque, and ball velocity. Results: There were no statistically significant effects of mound vs flat ground or distance variation on both arm speed or shoulder rotation. Arm slot was significantly higher on pitches from the mound at 60.5 ft [+4.58 (95% CI: 1.26, 7.90), p=0.007]. Elbow varus torque was significantly lower on throws from the mound [-1.88 (95% CI: -3.56, -0.20), p=0.03] and from a longer distance [-2.21 (95% CI: -3.89, -0.53), p=0.01]. Pitches thrown from the mound were significantly faster compared to flat ground at both distances, with throws at 60.5 ft of greater velocity than at 50.5 ft [+1.03 (95% CI: 0.66, 1.40), p<0.001]. Please see the Table for full results. Conclusion: The findings suggest that throwing from the mound may not be higher risk compared to flat ground, contrary to long-standing notions. The lower elbow varus torque and higher arm slot, which has previously been shown to be associated with reduced stress, from throwing from the mound may even indicate a protective effect. Compared to 50.5 ft, there was lower elbow varus torque and faster ball velocity at the longer distance, indicating that elbow stress and ball velocity may not correlate perfectly, and radar guns may not be an appropriate surrogate measure of elbow varus torque. A better understanding of the kinetic and kinematic implications of various throwing programs will allow for designing programs that are based on objective data to achieve the goal of preventing injuries in young baseball players. [Table: see text]


Sign in / Sign up

Export Citation Format

Share Document