The Effect Of Pitching With Underweight And Overweight Balls On Pitch Velocity In Collegiate Baseball Pitchers.

BACKGROUND: In an effort to improve overhand throw velocity in baseball pitchers, weighted implement training, which utilizes balls that are heavier or lighter than a competition ball, have been employed. Weighted ball programs have previously been used in baseball pitchers ranging from high school to professional with varying ball weights with mixed results (Straub, 1966; Brose and Hanson, 1967; DeRenne, 1985; DeRenne, 1990; van den Tillaar and Ettema, 2011). PURPOSE: To determine the effect of a commercially available weighted ball program on the throwing velocity of collegiate baseball pitchers over the course of an off-season. METHODS: This retrospective study examined pitch velocity for 56 varsity collegiate baseball pitchers at the University of Mississippi between 2012-2015. The weighted implement (WI) group (n=35) used weighted implement training in addition to normal throwing activities throughout the off-season while the normal throwing (NT) group (n=21) participated in normal throwing activities only. The WI group used baseballs that were 20% overweight (6 ounces), 20% underweight (4 ounces), and regulation weight (5 ounces) while the NT group used only the regulation weight baseball. A repeated measures ANOVA was conducted. Statistical significance was set at p?0.05. RESULTS: Pitch velocity did not significantly increase from the beginning of the off-season to the end of the off-season (p=0.071) for either group and there was no significant difference between the two groups (p=0.271). CONCLUSION: In varsity collegiate pitchers currently involved in general and sport specific training, the current weighted implement throwing program is no more effective than a normal throwing protocol

The effects of internally and externally directed attention during motor skill execution and learning

Focusing attention onto the intended outcome or goal of a movement (an External focus of attention) has been shown to be more beneficial to the learning and performance of movements than focusing onto the components of the movement being carried out (an Internal focus of attention). In this thesis, four studies assessed the effects of attentional focusing strategies on the learning and execution of motor skills during different situations. Study 1 demonstrated that an internal focus of attention during a suprapostural pointing task resulted in degraded postural control as well as larger movements of the hand and arm. In Study 2 novices using an external focus were more accurate in a dart throwing task than those using an internal focus, but no different from a control condition. In Study 3 two experiments investigated the effects of attentional focuses on postural control at rest and whilst fatigued. Postural control was no better using external focus when compared to an internal focus at rest, but was better than baseline. When fatigued (localised and generalised), balance was significantly deteriorated using an external focus, but not when an internal focus was used. In two experiments during Study 4 novices carrying out a dart throwing task used different attentional focusing instructions during practice and later performance. During practice sessions in Experiment 4.1 and 4.2 accuracy was not affected by attentional focusing instructions. Using an external focus during performance resulted in significantly better accuracy than using an internal focus. In Experiment 4.2, novices who preferred an internal focus but used an external focus during performance performed less accurately than participants who preferred the external focus. Findings demonstrate that the benefits of an external focus of attention is evident in performance situations, whereas an internal focus may be beneficial whilst fatigued and is not detrimental during practice

Limits to temporal synchronization in fundamental hand and finger actions

Coordinated movement is critical not only to sports technique and performance but to daily living and as such represents a fundamental area of research. Coordination requires being able to produce the right actions at the right time and has to incorporate perception, cognition, and forceful neuro-muscular interaction with the environment. Coordinated movements of the hands and fingers are some of the most complex activities undertaken where continuous learning and adaptation take place, but the temporal variability of the most basic movement components is still unknown. This thesis investigates the extent of temporal variability in the execution of four different simple hand and finger coordination tasks, with the purpose to find the various intrinsic temporal variability which limit the ability to coordinate the hands in space and time. Study one showed that in a synchronized bi-lateral two finger tapping test (<<1 cm movement to target) the best participant had a temporaltiming variability of 4.8 ms whereas the largest time variability could be as high as 24.8 ms. No obvious improvement was found after transfer practice, whereas the average time variability for asynchronized tapping decreased from 62.1 ms to 30.3 ms after instructed practice indicating a likely change in task grouping. Study two showed that in a unilateral thumb-index finger pinch and release test, the largest mean timing variability was 12 ms for pinching irrespective of performing the task in a slow alert manner or at a faster speed. However, the mean temporal variability for release was only 6.3 ms when the task was performed in a more alert manner and indicates that release is more accurately controlled temporally than grip. Study three suggested that in a unilateral sagittal plane throwing action of the lower arm and hand, that elbow and wrist coordination for dynamic index finger tip location was better with a radial-ulnar deviation, darts-type, throwing action than a wrist flexor-extensor type action, basketball free throw type action (the mean variability was 37.5 ms and 27.2 ms, respectively). Study four compared the variability in bi-lateral finger tapping between voluntary tapping and involuntary finger contraction tapping. Electrically stimulated neural contractions had significantly lower force onset variability than voluntary or direct magnetic stimulation of muscles (6 ms, 9.5 ms, and 10.3 ms for electrically stimulated, voluntary and Transcranial Magnetic Stimulation stimulated contraction). This work provides a comprehensive analysis of the temporal variability in various fundamental digital movement tasks that can aid with the understanding of basic human coordination in sporting, daily living and clinical areas

Sports Performance and Health

Sports performance is primarily associated with elite sport, however, recreational athletes are increasingly attempting to emulate elite athletes. Performance optimization is distinctly multidisciplinary. Optimized training concepts and the use of state-of-the-art technologies are crucial for improving performance. However, sports performance enhancement is in constant conflict with the protection of athletes’ health. Notwithstanding the known positive effects of physical activity on health, the prevention and management of sports injuries remain major challenges to be addressed. Accordingly, this Special Issue on "Sports Performance and Health" consists of 17 original research papers, one review paper, and one commentary, and covers a wide range of topics related to fatigue, movement asymmetries, optimization of sports performance by training, technique, and/or tactics enhancements, prevention and management of sports injuries, optimization of sports equipment to increase performance and/or decrease the risk of injury, and innovations for sports performance, health, and load monitoring. As this Special Issue offers several new insights and multidisciplinary perspectives on sports performance and health, readers from around the world who work in these areas are expected to benefit from this Special Issue collection

Attention and time constraints in performing and learning a table tennis forehand shot

This is a section on p. S95 of article 'Verbal and Poster: Motor Development, Motor Learning and Control, and Sport and Exercise Psychology' in Journal of Sport and Exercise Psychology, 2010, v.32, p.S36-S237published_or_final_versio

EEG coherence between the verbal-analytical region (T3) and the motor-planning region (Fz) increases under stress in explicit motor learners but not implicit motor learners

This journal supplement contains abstracts of NASPSPA 2010Free Communications - Verbal and Poster: Motor Learning and Controlpublished_or_final_versionThe Annual Conference of the North American Society for the Psychology of Sport and Physical Activity (NASPSPA 2010), Tucson, AZ., 10-12 June 2010. In Journal of Sport and Exercise Psychology, 2010, v. 32 suppl., p. S13

The effect of attentional focus cues on corticospinal excitability and neuromuscular efficiency during a sustained task

Attentional focus has been studied in the context of physical activity and sports as a form of feedback or instruction that aims to improve performance by directing a person's focus either externally or internally. Adopting an external focus (i.e., focus on goals and environment) has been shown to be beneficial to performance relative to an internal focus (i.e., focus on self and body movements) for a range of tasks. However, little is understood about the mechanisms underlying improved performance associated with external focus. Emerging neuroimaging studies have shown changes in brain activity relative to the direction of attention, and data from electromyography shows changes at the muscular level. To bridge the gap in knowledge between what is seen in the brain and the muscle during external and internal focus, we explored corticospinal excitability, which is the connection between brain and muscle and reflects the ability of the motor cortex to generate movement. Understanding the relationship between attentional focus and corticospinal excitability is important for advancing our understanding of basic neural mechanisms and informing the development of interventions aimed at improving motor function and physical performance in individuals