Nissen, Carl W.; Solomito, Matthew; Garibay, Erin; Õunpuu, Sylvia; Westwell, Melany
Background: Baseball professionals believe that pitching from a mound can increase the stresses placed on the body. Hypothesis: There is no difference in kinematics or kinetics in pitching from a mound versus flat-ground conditions in adolescent baseball pitchers. Study Design: Laboratory investigation. Methods: The fastball pitching motions of 15 adolescent baseball pitchers, including upper extremity kinematics and kinetics and lead- and trail-leg kinematics, were evaluated while pitching from the mound and flat ground. Student t tests were used to determine the differences between the 2 testing conditions. Results: Maximum external glenohumeral rotation was similar between the 2 conditions (134° ± 14° mound vs 133° ± 14° flat ground, P = 0.10). Ankle plantar flexion of the lead leg at ball release was greater in the flat-ground condition (−20° ± 10° mound vs −15° ± 12° flat ground, P = 0.01). A statistically significant increase in glenohumeral internal rotation moment (33.6 ± 12.1 Nm mound vs 31.7 ± 11.6 Nm flat ground, P = 0.01) and an increase in elbow varus moment (33.3 ± 12.3 Nm mound vs 31.4 ± 11.8 Nm flat ground, P = 0.02) was measured when pitching from the mound as compared with flat ground. Conclusion: Pitching from the mound causes increased stress on the shoulder and elbow of adolescent pitchers as compared with that from flat ground. Clinical Relevance: The differences in kinematics as well as increased moments in the shoulder and elbow are helpful for pitchers and their coaches to know at the beginning of their season or as they return from injury or surgery. Pitchers in these situations should start their pitching progression on flat ground and progress to the mound. PMID:24427428
Safran, M R; Borsa, P A; Lephart, S M; Fu, F H; Warner, J J
We examined proprioceptive differences between the dominant and nondominant shoulders of 21 collegiate baseball pitchers without a history of shoulder instability or surgery. A proprioceptive testing device was used to measure kinesthesia and joint position sense. Joint position sense was significantly (P =.05) more accurate in the nondominant shoulder than in the dominant shoulder when starting at 75% of maximal external rotation and moving into internal rotation. There were no significant differences for proprioception in the other measured positions or with kinesthesia testing. Six pitchers with recent shoulder pain had a significant (P =.04) kinesthetic deficit in the symptomatic dominant shoulder compared with the asymptomatic shoulder, as measured in neutral rotation moving into internal rotation. The net effect of training, exercise-induced laxity, and increased external rotation in baseball pitchers does not affect proprioception, although shoulder pain, possibly due to rotator cuff inflammation or tendinitis, is associated with reduced kinesthetic sensation.
Kageyama, Masahiro; Sugiyama, Takashi; Kanehisa, Hiroaki; Maeda, Akira
The purpose of this study was to clarify the differences between adolescent and collegiate baseball pitchers in the kinematic and kinetic profiles of the trunk and lower limbs during the pitching motion. The subjects were thirty-two adolescent baseball pitchers aged 12-15 years (APG) and thirty collegiate baseball pitchers aged 18-22 years (CPG). Three-dimensional motion analysis with a comprehensive lower-extremity model was used to evaluate kinematic and kinetic parameters during baseball pitching. The ground reaction forces (GRFs) of the pivot and stride legs during pitching were determined using two multicomponent force plates. The joint torques of hip, knee, and ankle were calculated by the inverse-dynamics computation of musculoskeletal human models using motion-capture data. To eliminate any effect of variation in body size, kinetic and GRFs data were normalized by dividing them by body mass. The velocity of a pitched ball was significantly higher (p < 0.01) in CPG (35.2 ± 1.9 m·s-1) than in the APG (30.7 ± 2.7 m·s-1). Most kinematic parameters for the lower limbs were similar between the CPG and the APG. Maximum Fy (toward the throwing direction) on the pivot leg and Fy and resultant forces on the stride leg at ball release were significantly greater in the CPG than in the APG (p < 0.05). Hip and knee joint torques on the lower limbs were significantly greater in the CPG than in the APG (p < 0.05). The present study indicates that the kinematics of lower limbs during baseball pitching are similar between adolescent and collegiate pitchers, but the momentum of the lower limbs during pitching is lower in adolescent pitchers than in collegiate ones, even when the difference in body mass is considered. Key points Collegiate baseball pitchers can generate the hip and knee joint torques on the pivot leg for accelerating the body forward. Collegiate baseball pitchers can generate the hip and knee joint torques to control/stabilize the stride leg in order to
Li, Xinning; Heffernan, Michael J; Mortimer, Errol S
Lower extremity stress fractures are relatively common among competitive athletes. Stress fractures of the upper extremity, however, are rare and most have been reported in the literature as case reports. We present a case of an adolescent baseball pitcher who had both proximal humeral and ulnar shaft stress fractures, as well as spondylolysis of the lumbar spine. This particular patient also had an underlying endocrine abnormality of secondary hyperparathyroidism with a deficiency in vitamin D. A bone mineral density panel demonstrated a high T score (+2.79 SD above the mean) and the patient's biologic bone age was noted to be 2 years ahead of his chronologic age. The patient was treated with a course of vitamin D and calcium supplementation. After treatment, both the vitamin D and parathyroid hormone returned to normal levels. The upper extremity stress fractures and spondylolysis were managed conservatively and he was able to return to full activity and baseball. For patients who present with multiple stress fractures not associated with consistent high levels of repeated stress, a bone mineral density panel should be considered. If vitamin D deficiency is present, a course of oral supplementation may be considered in the management. An endocrinology consult should also be considered in patients who present with multiple stress fractures. Conservative management of upper extremity stress fractures and spondylolysis was successful in returning this patient back to his previous activity level.
Fleisig, Glenn S; Weber, Adam; Hassell, Nina; Andrews, James R
There is concern among sports medicine practitioners that the number of youth baseball pitchers with elbow injuries appears to be increasing. Research points to overuse as the principle risk factor. The risk of elbow pain in youth pitchers is correlated with the number of pitches thrown in a game and in a season. Adolescents who competitively pitch more than 85 pitches per game, more than 8 months out of a year, or with arm fatigue are several times more likely to require elbow surgery. Poor pitching mechanics also appear to contribute to injury risk. Existing research does not show a significant correlation between curveballs and injury. Adults should help youth pitchers avoid fatigue, overuse, and improper mechanics. If elbow pain develops, the youth pitcher should be evaluated by a sports medicine physician.
McCulloch, Patrick C.; Patel, Jayesh K.; Ramkumar, Prem N.; Noble, Philip C.; Lintner, David M.
Background: There is a renewed interest in examining the association between hip range of motion and injury in athletes, and the data on baseball players are conflicting. Understanding whether asymmetrical hip rotation is a normal adaptation or a risk factor for injury will help therapists, trainers, and physicians develop rehabilitation programs to improve kinetic energy transfer and prevent injury. As our knowledge of hip pathology among baseball pitchers improves, establishing baselines for hip motion is critical in the further assessment of injury. Hypothesis: Because of the repetitive nature of throwing sports and the adaptive changes documented in the shoulder, elite baseball pitchers would have characteristic patterns of hip internal and external rotations on their dominant throwing side (stance) and their nondominant side (stride) in extension. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Computer software was used to measure passive internal and external rotations on digital photographs of 111 professional baseball pitchers. Results: In right-handed pitchers, there was significantly more internal rotation in the stance hip than the stride hip (32.2° ± 8.2° vs 30.8° ± 8.4°; P = .0349) and significantly more external rotation in the stride hip than the stance hip (36.3° ± 7.7° vs 30.8° ± 9.7°; P < .0001). While the mean difference in external rotation was 4.7°, 32% of the subjects had a >10° increase in external rotation on the stride hip relative to the stance hip. This population was statistically different from the remaining group for older age (P = .0053), lower body mass index (P = .0379), and more years in professional baseball (P = .0328). In the smaller number of left-handed pitchers, side-to-side differences in hip rotation were found but were not statistically significant. Conclusion: Pitchers showed more internal rotation on their stance hip and more external rotation on their stride hip. Although the mean
Zaremski, Jason L; Krabak, Brian J
Since 1996, when the first article on pitch restriction recommendations was published, the number of research articles involving skeletally immature pitchers has increased. Potential shoulder injuries in this age group are proximal humeral epiphysiolysis, glenohumeral instability, rotator cuff dysfunction, and superior labrum anteroposterior lesions. Fatigue, improper biomechanics, and overuse are the most common reasons for these injuries. In the hopes of preventing injury to young pitchers, numerous organizations, including the USA Baseball Medical & Safety Advisory Committee, The American Sports Medicine Institute, Little League Baseball & Softball, and the Long Term Athlete Development Program for Baseball Canada, have developed recommendations on pitching restrictions that include limits on pitch count, pitches per week, pitches per season, and rest between pitching. Awareness by sports medicine providers, coaches, and parents/guardians of the most up-to-date recommendations on injury prevention and return to play guidelines should reduce the incidence of acute and chronic injuries in adolescent baseball pitchers.
Chu, Yungchien; Fleisig, Glenn S; Simpson, Kathy J; Andrews, James R
The purpose of the current study was to identify the biomechanical features of elite female baseball pitching. Kinematics and kinetics of eleven elite female baseball pitchers were reported and compared with eleven elite male pitchers. Results suggested that females share many similarities with males in pitching kinematics, with a few significant differences. Specifically, at the instant of stride foot contact, a female pitcher had a shorter and more open stride and less separation between pelvis orientation and upper torso orientation. From foot contact to ball release, a female pitcher produced lower peak angular velocity for throwing elbow extension and stride knee extension. Ball velocity was lower for the female. Foot contact to ball release took more time for a female pitcher. Maximal proximal forces at the shoulder and elbow joints were less for a female pitcher.
Oliver, Gretchen D; Weimar, Wendi H
Oliver, GD and Weimar, WH. Hip and shoulder range of motion in youth baseball pitchers. J Strength Cond Res 30(10): 2823-2827, 2016-Lack of range of motion (ROM) has long been suspected as contributing to injury in baseball pitchers. However, all previous ROM research has focused on collegiate and professional pitchers. It was thus the purpose of this study to measure and evaluate bilateral hip and throwing shoulder rotational passive range of motion (PROM) in youth baseball pitchers. Twenty-six youth baseball pitchers (11.3 ± 1.0 years; 152.4 ± 9.0 cm; 47.5 ± 11.3 kg) with no history of injury participated. Bilateral hip and throwing shoulder rotational PROM was measured. There were no significant side-to-side differences for the hip variables (p ≥ 0.05). Shoulder external rotation (ER) was significantly greater than shoulder internal rotation (IR). And the lead leg hip had significantly greater ER than IR. Shoulder ER revealed significant correlations with both lead and stance hip IR (r = 0.45, p = 0.02 and r = 0.48, p = 0.01, respectively). The youth baseball pitchers in this study displayed similar PROM patterns as collegiate and professional baseball pitchers. Additionally, our youth baseball pitchers also presented strong relationships between hip and shoulder PROM. This study reveals that the PROM patterns displayed by these youth may indicate that their available ROM could survive maturation. It is therefore suggested that clinical focus be directed to maintaining hip and shoulder rotational ROM throughout maturation in attempt to determine a possible relations between injurious mechanisms and performance enhancement.
Pei-Hsi Chou, Paul; Huang, Yen-Po; Gu, Yi-Hsuan; Liu, Chiang; Chen, Shen-Kai; Hsu, Kai-Cheng; Wang, Rong-Tyai; Huang, Ming-Jer; Lin, Hwai-Ting
Repetitive overhead throwing may result in overuse injuries and a change in the pitching mechanics of a baseball pitcher. Accordingly, the purpose of this study is to quantify the changes in the muscle strength and pitching motion kinematics in the late-innings stage of a baseball game. Sixteen healthy baseball pitchers (16.77 ± 0.73 years) recruited from a high school, which won the National High School Baseball Championship in Taiwan in 2011; each performed 100 pitches in a bullpen throwing session. Isometric muscle strength measurements and joint kinematic data were obtained before and after the throwing session. The mean Borg's Rating of Perceived Exertion index was found to have a value of 14.14, indicating a medium-to-large degree of perceived tiredness. The results showed that the ball velocity and horizontal abduction angle decreased significantly as the pitchers became tired. Moreover, the upper torso forward tilt and knee flexion angle both increased significantly at the moment of ball release. Finally, the muscle strength of the upper extremity remained decreased 2 days after the bullpen throwing session. Overall, the results suggest that an adequate amount of rest and specific strengthening programs for the shoulder external rotator, shoulder internal rotator, shoulder flexor, shoulder extensor, shoulder adductor, and shoulder abductor muscles are recommended to the coaches and for adolescent baseball pitchers. In addition, the changes in pitching mechanics noted in this study should be carefully monitored during the course of a baseball game to minimize the risk for overuse injuries.
Hibberd, Elizabeth E; Brown, J Rodney; Hoffer, Joseph T
The ulnar collateral ligament stabilizes the elbow joint from valgus stress associated with the throwing motion. During baseball pitching, this ligament is subjected to tremendous stress and injury if the force on the ulnar collateral ligament during pitching exceeds the physiological limits of the ligament. Injuries to the throwing elbow in baseball pitchers result in significant time loss and typically surgical intervention. The purpose of this paper is to provide a review of current information to sports medicine clinicians on injury epidemiology, injury mechanics, injury risk factors, injury prevention, surgical interventions, nonsurgical interventions, rehabilitation, and return to play outcomes in baseball pitchers of all levels. PMID:26635490
Objective: To describe a case of chronic Little Leaguer’s Shoulder in reference to pain presentation, physical capabilities, and recovery time. Clinical Features: A 17-year-old, junior baseball pitcher presented with shoulder pain when performing high velocity pitching. Conservative treatment for an assumed soft tissue injury failed to resolve the pain, which was regularly aggravated by pitching, and which subsequently prompted further evaluation, and eventual confirmation of Little Leaguer’s Shoulder on subsequent computerized tomography (CT) imaging. Intervention and Outcome: Prior to proper diagnosis, conservative treatment had consisted of activity modification, spinal adjusting, laser therapy, shockwave therapy, Active Release Techniques®, Kinesiotape,® and rehabilitation. Later, rehabilitation, consisting of general muscle and core strengthening, continued for a further six months under the supervision of college athletic trainers. The athlete was able to return to normal pitching duties approximately 12 months later. Summary: In this case, a potentially damaging bone injury masquerading as a simple musculo-tendinous injury created a diagnostic challenge. The patient eventually recovered with rest, time, strengthening, and eventual compliance to prescribed activity modification. PMID:26815884
Fleisig, Glenn S.; Andrews, James R.
Context: Although baseball is a relatively safe sport, numerous reports suggest a rapid rise in elbow injury rate among youth baseball pitchers. Evidence Acquisition: PubMed was searched for epidemiologic, biomechanical, and clinical studies of elbow injuries in baseball (keywords: “youth OR adolescent” AND baseball AND pitching AND “ulnar collateral ligament OR elbow”; published January 2000 – April 2012). Studies with relevance to youth baseball pitchers were reviewed. Relevant references from these articles were also retrieved and reviewed. Original data, insight, and recommendations were added. Results: The majority of baseball elbow injuries are noncontact injuries to the dominant arm resulting from repetitive pitching. Five percent of youth pitchers suffer a serious elbow or shoulder injury (requiring surgery or retirement from baseball) within 10 years. The risk factor with the strongest correlation to injury is amount of pitching. Specifically, increased pitches per game, innings pitched per season, and months pitched per year are all associated with increased risk of elbow injury. Pitching while fatigued and pitching for concurrent teams are also associated with increased risk. Pitchers who also play catcher have an increased injury risk, perhaps due to the quantity of throws playing catcher adds to the athlete’s arm. Another risk factor is poor pitching biomechanics. Improper biomechanics may increase the torque and force produced about the elbow during each pitch. Although throwing breaking pitches at a young age has been suggested as a risk factor, existing clinical, epidemiologic, and biomechanical data do not support this claim. Conclusions: Some elbow injuries to youth baseball pitchers can be prevented with safety rules, recommendations, education, and common sense. Scientific and medical organizations have published safety rules and recommendations, with emphasis on prevention of overuse and pitching while fatigued. Strength
Ricchetti, E T; Weidner, Z; Lawrence, J T R; Sennett, B J; Huffman, G R
Little is known about outcomes of glenoid labral repair in Major League Baseball (MLB) pitchers. We hypothesized that following repair, pitching performance would not be significantly different from an uninjured cohort. Fifty-one pitchers were identified who pitched in at least one MLB game prior to undergoing isolated glenoid labral repair. For the three years prior to and following surgery, demographic and performance variables were analyzed for an association with labral injury and repair, and compared to a control cohort of MLB pitchers without history of repair. Following surgery, 72.5% of pitchers returned to MLB at a mean of 13.1 months with no significant change in performance. Starting pitchers had a higher risk of labral injury requiring repair (p< or =0.05). Pitchers that returned to play averaged more innings pitched in the seasons prior to surgery and had a higher body mass index than those that did not return to play (p< or =0.05). Approximately 70% of MLB pitchers undergoing labral repair can be expected to return to competition postoperatively with no significant change in performance. Starting pitchers are more likely to undergo repair, but pitchers with greater preoperative innings pitched per season have a greater likelihood of returning to play.
Cornell, David J; Paxson, Jeffrey L; Caplinger, Roger A; Seligman, Joshua R; Davis, Nicholas A; Ebersole, Kyle T
Cornell, DJ, Paxson, JL, Caplinger, RA, Seligman, JR, Davis, NA, and Ebersole, KT. Resting heart rate variability among professional baseball starting pitchers. J Strength Cond Res 31(3): 575-581, 2017-The purpose of this study was to examine the changes in resting heart rate variability (HRV) across a 5-day pitching rotation schedule among professional baseball starting pitchers. The HRV data were collected daily among 8 Single-A level professional baseball starting pitchers (mean ± SD, age = 21.9 ± 1.3 years; height = 185.4 ± 3.6 cm; weight = 85.2 ± 7.5 kg) throughout the entire baseball season with the participant quietly lying supine for 10 minutes. The HRV was quantified by calculating the natural log of the square root of the mean sum of the squared differences (lnRMSSD) during the middle 5 minutes of each R-R series data file. A split-plot repeated-measures analysis of variance was used to examine the influence of pitching rotation day on resting lnRMSSD. A statistically significant main effect of rotation day was identified (F4,706 = 3.139, p = 0.029). Follow-up pairwise analyses indicated that resting lnRMSSD on day 2 was significantly (p ≤ 0.05) lower than all other rotation days. In addition, a statistically significant main effect of pitcher was also identified (F7,706 = 83.388, p < 0.001). These results suggest that professional baseball starting pitchers display altered autonomic nervous system function 1 day after completing a normally scheduled start, as day 2 resting HRV was significantly lower than all other rotation days. In addition, the season average resting lnRMSSD varied among participants, implying that single-subject analysis of resting measures of HRV may be more appropriate when monitoring cumulative workload among this cohort population of athletes.
Dun, Shouchen; Fleisig, Glenn S; Loftice, Jeremy; Kingsley, David; Andrews, James R
Joint range of motion and physical capacities have been shown to change with age in both throwing athletes and non-athletes. The age of professional baseball pitchers could span from late teens to mid-40s. However, the effects of age on the pitching kinematics among professional baseball pitchers are still unknown. In this study, 67 healthy professional baseball pitchers were tested using a 3D motion analysis system. Their mean age was 23.7+/-3.3 years (range 18.8-34.4). The 12 pitchers more than one standard deviation older than the mean (i.e., older than 27.0 years) were categorized into the older group, and the 10 pitchers more than one standard deviation younger than the mean (i.e., younger than 20.4 years) were defined as the younger group. In all, 18 kinematic variables (14 position and 4 velocity) were calculated, and Student's t-tests were used to compare the variables between the two groups. Six position variables were found to be significantly different between the two groups. At the instant of lead foot contact, the older group had a shorter stride, a more closed pelvis orientation, and a more closed upper trunk orientation. The older group also produced less shoulder external rotation during the arm cocking phase, more lead knee flexion at ball release, and less forward trunk tilt at ball release. Ball velocity and body segment velocity variables showed no significant differences between the two groups. Thus, differences in specific pitching kinematic variables among professional baseball pitchers of different age groups were not associated with significant differences in ball velocities between groups. The current results suggest that both biological changes and technique adaptations occur during the career of a professional baseball pitcher.
Klemish, David; Ramger, Benjamin; Vittetoe, Kelly; Reiter, Jerome P; Tokdar, Surya T; Appelbaum, Lawrence Gregory
This study aimed to evaluate the possibility that differences in sensorimotor abilities exist between hitters and pitchers in a large cohort of baseball players of varying levels of experience. Secondary data analysis was performed on 9 sensorimotor tasks comprising the Nike Sensory Station assessment battery. Bayesian hierarchical regression modelling was applied to test for differences between pitchers and hitters in data from 566 baseball players (112 high school, 85 college, 369 professional) collected at 20 testing centres. Explanatory variables including height, handedness, eye dominance, concussion history, and player position were modelled along with age curves using basis regression splines. Regression analyses revealed better performance for hitters relative to pitchers at the professional level in the visual clarity and depth perception tasks, but these differences did not exist at the high school or college levels. No significant differences were observed in the other 7 measures of sensorimotor capabilities included in the test battery, and no systematic biases were found between the testing centres. These findings, indicating that professional-level hitters have better visual acuity and depth perception than professional-level pitchers, affirm the notion that highly experienced athletes have differing perceptual skills. Findings are discussed in relation to deliberate practice theory.
Gerrie, Brayden J; Harris, Joshua D; Lintner, David M; McCulloch, Patrick C
Stress fractures of the first rib on the dominant throwing side are well-described in baseball pitchers; however, lower thoracic rib fractures are not commonly recognized. While common in other sports such as rowing, there is scant literature on these injuries in baseball. Intercostal muscle strains are commonly diagnosed in baseball pitchers and have a nearly identical presentation but also a highly variable healing time. The diagnosis of a rib stress fracture can predict a more protracted recovery. This case series presents two collegiate baseball pitchers on one team during the same season who were originally diagnosed with intercostal muscle strains, which following magnetic resonance imaging (MRI) were found to have actually sustained lower thoracic rib stress fractures. The first sustained a stress fracture of the posterior aspect of the right 8th rib on the dominant arm side, while the second presented with a left-sided 10th rib stress fracture on the nondominant arm side. In both cases, MRI was used to visualize the fractures as plain radiographs are insensitive and commonly negative early in patient presentation. Patients were treated with activity modification, and symptomatic management for 4-6 weeks with a graduated return to throwing and competition by 8-10 weeks. The repetitive high stresses incurred by pitching may cause either dominant or nondominant rib stress fractures and this should be included in the differential diagnosis of thoracic injuries in throwers. It is especially important that athletic trainers and team physicians consider this diagnosis, as rib fractures may have a protracted course and delayed return to play. Additionally, using the appropriate imaging techniques to establish an accurate diagnosis can help inform return-to-play decisions, which have important practical applications in baseball, such as roster management and eligibility.
Oliver, Gretchen D; Weimar, Wendi H; Plummer, Hillary A
The baseball pitching motion is a total kinetic chain activity that must efficiently use both the upper and lower extremity. Of particular importance is the scapular motion, which is critical for humeral positioning and proper alignment of shoulder musculature. It was hypothesized that scapular stability is enhanced by pelvic girdle stability. Therefore, it was the purpose of this study to determine the muscle activations of selected pelvic and scapular stabilizing muscles during a fastball pitch in youth baseball pitchers. Twenty youth baseball pitchers (age: 11.3 + 1.0 years; height: 152.4 + 9.0 cm; weight: 47.5 + 11.3 kg) were recorded throwing 4-seam fastballs for strikes. Data revealed moderate (20-39% maximum voluntary isometric contraction [MVIC]) to moderately strong (>40% MVIC) activation of the ipsilateral (throwing arm side) gluteus medius, upper trapezius, and serratus anterior throughout phases 2 (maximum shoulder external rotation to ball release) and 3 (ball release to maximum shoulder internal rotation). Moderately strong activation (>40% MVIC) of the upper trapezius and serratus anterior was noted during phases 2 and 3 of the pitching motion. Pearson's product-moment correlation revealed significant relationships between bilateral gluteus medius and the force couples about the scapula during all 3 phases of the pitching motion. The results of this study provide important data that improve the understanding of the muscular relationship between the pelvic and scapular stabilizers during the fastball pitch. Training and rehabilitation programs should consider focusing on lumbopelvic-hip and scapular muscle strengthening as well as coordinated strengthening of the pelvic and scapular stabilizers, in baseball pitchers.
Holt, Taylor; Oliver, Gretchen D
The purpose of this study was to examine the relationship between dynamic hip rotational range of motion and upper extremity kinematics during baseball pitching. Thirty-one youth baseball pitchers (10.87 ± 0.92 years; 150.03 ± 5.48 cm; 44.83 ± 8.04 kg) participated. A strong correlation was found between stance hip rotation and scapular upward rotation at maximum shoulder external rotation (r = 0.531, P = 0.002) and at ball release (r = 0.536, P = 0.002). No statistically significant correlations were found between dynamic hip rotational range of motion and passive hip range of motion. Hip range of motion deficits can constrain pelvis rotation and limit energy generation in the lower extremities. Shoulder pathomechanics can then develop as greater responsibility is placed on the shoulder to generate the energy lost from the proximal segments, increasing risk of upper extremity injury. Additionally, it appears that passive seated measurements of hip range of motion may not accurately reflect the dynamic range of motion of the hips through the progression of the pitch cycle.
McNamara, Andrew R; Ensell, Scott; Farley, Timothy D
Friction blisters are a common sequela of many athletic activities. Their significance can range from minor annoyance to major performance disruptions. The latter is particularly true in baseball pitchers, who sustain repeated trauma between the baseball seams and the fingers of the pitching hand, predominately at the tips of the index and long fingers. Since 2010, 6 Major League Baseball (MLB) players accounted for 7 stints on the disabled list (DL) due to blisters. These injuries resulted in a total of 151 days spent on the DL. Since 2012, 8 minor league players spent time on the DL due to blisters. Moreover, there have been several documented and publicized instances of professional baseball pitchers suffering blisters that did not require placement on the DL but did result in injury time and missed starts. The purpose of this article is to review the etiology and pathophysiology of friction blisters with particular reference to baseball pitchers; provide an overview of past and current prevention methods; and discuss our experience in treating friction blisters in MLB pitchers.
Zaremski, Jason L.; Horodyski, MaryBeth; Donlan, Robert M.; Brisbane, Sonya Tang; Farmer, Kevin W.
Background: There has been a significant amount of research in the prevention of throwing injuries. However, one area of research that is lacking is geographic location of play. Warm climates may permit year-round play and increased exposure to throwing arm injury risk. Hypotheses: (1) Pitchers from southern institutions would have greater rates of ulnar collateral ligament reconstruction (UCL-R) compared with pitchers from northern institutions. (2) Pitchers originating from high school teams in warm weather states would have a greater risk of undergoing UCL-R while in college. Study Design: Descriptive epidemiological study. Methods: This study was completed by reviewing publicly obtained records of male collegiate baseball players during the 2008 through 2014 seasons. Data were accessed through online search engines, online baseball media guides, and school websites. Results: A total of 5315 player-years and 2575 pitcher-years were identified. Fifty-eight UCL-R cases were found in collegiate pitchers, 40 of which occurred in the Southeastern Conference (SEC) and 18 in the Big Ten. More injuries (36/58) occurred in pitchers who participated in high school baseball in southern states as compared with northern states (22/58), regardless of location of collegiate participation (χ2 = 28.8, P < .05). The injury rate for pitchers who participated in high school baseball in southern states was 25.3 per 1000 player-years versus 19.1 per 1000 player-years in northern states, with a risk ratio of 1.32 (χ2 = 0.89, P = .35). The injury rate for the SEC versus Big Ten pitchers was 13.3 per 1000 player-years versus 7.8 per 1000 player-years, with a risk ratio of 1.71 (χ2 = 1.45, P = .23). Conclusion: There is a greater likelihood of undergoing UCL-R in the SEC compared with the Big Ten. There is also an increased risk for UCL-R for pitchers who played high school baseball in southern states versus northern states, irrespective of collegiate play location. Clinical Relevance
Popchak, Adam; Burnett, Thomas; Weber, Nicholas; Boninger, Michael
The baseball and medical communities have recognized injuries of the upper extremity associated with the overhead throwing motion and have examined manners in which to reduce risk. The authors examine special features of the adolescent pitcher as compared with skeletally mature pitchers and characteristics of pitch mechanics, type, velocity, fatigue, and overuse. A summary is presented on previously identified risk factors as they relate to pitching injuries. Development, use, and compliance with the most current pitching guidelines in youth baseball, based on the available evidence, will be presented and examined. In an increasingly competitive environment, identifying known risk factors and potential signs of pathology as well as implementing the current best evidence in a consistent manner are important steps in decreasing injury risk of youth baseball pitchers. More research is needed to evaluate the effectiveness of pitching guidelines in the short and long term and to focus on manners in which to increase compliance with best practice procedures throughout youth baseball organizations.
Cheatham, Scott W.; Shimamura, Kathryn Kumagai; Kolber, Morey J.
The purpose of this study was to measure passive hip internal (IR) and external rotation (ER) range of motion (ROM) in collegiate baseball pitchers and compare to published youth and professional values. Measures were taken on the bilateral hips of 29 participants (mean age 20.0±1.4, range 18–22 years). Results identified no significant differences between the stance and stride hip in collegiate right handed pitchers for IR (p= 0.22, ES 0.23) and ER (p=.08, ES= 0.25). There was no significant difference in left handed pitchers for IR (p= 0.80, ES= 0.11) and ER (p= 0.56, ES= 0.15). When comparing youth to collegiate, IR increased in the stance (2º) and stride (5º) hip and an increase in the stance (5º) and stride (5º) hip were present for ER as well. From collegiate to professional, IR increased in the stance (4º) and stride (3º) hip whereas a decrease in the stance (9º) and stride (12º) hip was present for ER. The data suggests an increase in passive ROM from youth to collegiate and a decrease from collegiate to professional. Understanding passive hip ROM values among the different levels of pitchers may assist clinicians in developing time dependent interventions to prevent future injury and enhance performance. PMID:27713579
Cheatham, Scott W; Shimamura, Kathryn Kumagai; Kolber, Morey J
The purpose of this study was to measure passive hip internal (IR) and external rotation (ER) range of motion (ROM) in collegiate baseball pitchers and compare to published youth and professional values. Measures were taken on the bilateral hips of 29 participants (mean age 20.0±1.4, range 18-22 years). Results identified no significant differences between the stance and stride hip in collegiate right handed pitchers for IR (p= 0.22, ES 0.23) and ER (p=.08, ES= 0.25). There was no significant difference in left handed pitchers for IR (p= 0.80, ES= 0.11) and ER (p= 0.56, ES= 0.15). When comparing youth to collegiate, IR increased in the stance (2º) and stride (5º) hip and an increase in the stance (5º) and stride (5º) hip were present for ER as well. From collegiate to professional, IR increased in the stance (4º) and stride (3º) hip whereas a decrease in the stance (9º) and stride (12º) hip was present for ER. The data suggests an increase in passive ROM from youth to collegiate and a decrease from collegiate to professional. Understanding passive hip ROM values among the different levels of pitchers may assist clinicians in developing time dependent interventions to prevent future injury and enhance performance.
Kageyama, Masahiro; Sugiyama, Takashi; Takai, Yohei; Kanehisa, Hiroaki; Maeda, Akira
The purpose of this study was to clarify differences in the kinematic and kinetic profiles of the trunk and lower extremities during baseball pitching in collegiate baseball pitchers, in relation to differences in the pitched ball velocity. The subjects were 30 collegiate baseball pitchers aged 18 to 22 yrs, who were assigned to high- (HG, 37.4 ± 0.8 m·s-1) and low-pitched-ball-velocity groups (LG, 33.3 ± 0.8 m·s-1). Three-dimensional motion analysis with a comprehensive lower-extremity model was used to evaluate kinematic and kinetic parameters during baseball pitching. The ground-reaction forces (GRF) of the pivot and stride legs during pitching were determined using two multicomponent force plates. The joint torques of hip, knee, and ankle were calculated using inverse-dynamics computation of a musculoskeletal human model. To eliminate any effect of variation in body size, kinetic and GRF data were normalized by dividing them by body mass. The maxima and minima of GRF (Fy, Fz, and resultant forces) on the pivot and stride leg were significantly greater in the HG than in the LG (p < 0.05). Furthermore, Fy, Fz, and resultant forces on the stride leg at maximum shoulder external rotation and ball release were significantly greater in the HG than in the LG (p < 0.05). The hip abduction, hip internal rotation and knee extension torques of the pivot leg and the hip adduction torque of the stride leg when it contacted the ground were significantly greater in the HG than in the LG (p < 0.05). These results indicate that, compared with low-ball-velocity pitchers, high-ball-velocity pitchers can generate greater momentum of the lower limbs during baseball pitching. Key points High-ball-velocity pitchers are characterized by greater momentum of the lower limbs during pitching motion. For high-pitched-ball velocity, stabilizing lower limbs during pitching plays an important role in order to increase the rotation and forward motion of the trunk. Computation of the lower
Cornell, David J; Paxson, Jeffrey L; Caplinger, Roger A; Seligman, Joshua R; Davis, Nicholas A; Flees, Robert J; Ebersole, Kyle T
Cornell, DJ, Paxson, JL, Caplinger, RA, Seligman, JR, Davis, NA, Flees, RJ, and Ebersole, KT. In-game heart rate responses among professional baseball starting pitchers. J Strength Cond Res 31(1): 24-29, 2017-The purpose of the current study was to characterize the in-game heart rate (HR) responses of baseball pitching. In-game HR was recorded from 16 professional baseball starting pitchers (mean ± SD, age = 22.1 ± 1.3 years; height = 187.9 ± 4.4 cm; weight = 90.5 ± 9.5 kg) for a total of 682 innings (home = 381, away = 301). All analyzed HR data were then normalized to each pitcher's age-predicted maximal HR (%HRmax). The group mean ± SD in-game %HRmax among all pitchers was 84.8 ± 3.9%, suggesting that baseball pitching is predominantly an anaerobic task. A split-plot mixed-model repeated measures analysis of variance identified a significant interaction effect between inning and game location (p = 0.042). Follow-up simple effects indicated that the in-game %HRmax was significantly different across innings, but only during home starts (p < 0.001). Specifically, pairwise analyses indicated that the in-game %HRmax during home starts were significantly (p ≤ 0.05) higher in the first and second innings than in all other innings. In addition, follow-up simple effects indicated that the in-game %HRmax was significantly (p = 0.017) higher during home starts than away starts in the first inning (87.3 ± 3.6% vs. 85.8 vs. 3.8%, respectively). Thus, it is possible that inning-dependent psychological factors may have contributed to the observed changes in in-game physiological intensity across innings and that these factors are specific to game location. Consequently, strength and conditioning practitioners should prescribe high-intensity exercises when developing conditioning programs for professional baseball starting pitchers.
Kerut, Edmund Kenneth; Kerut, Denise Goodfellow; Fleisig, Glenn S; Andrews, James R
The advent of youth year-round baseball has come with an increased incidence of pitching related injury and surgery, most notably involving the shoulder and elbow (ulnar collateral ligament). These injuries become evident in high school and college, but begin at the youth level. Several studies have identified baseball pitching risk factors during youth that increase likelihood for injury and surgery in subsequent years. Based on these studies, the USA Baseball Medical & Safety Advisory Committee has published guidelines for pitching that include limits on pitch count and pitches per week and season as well as recommendations for number of rest days between pitching. Also, recommendations include the restriction of breaking balls prior to puberty, the importance of instruction for proper pitching mechanics as early as possible in development, and at least three months of rest after a season. This review is intended to help guide primary care physicians and pediatricians when discussing youth pitching and injury prevention with parents and coaches.
Erickson, Brandon J.; Cvetanovich, Gregory; Bach, Bernard R.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.
Objectives: Background: Ulnar collateral ligament reconstruction (UCLR) has become a common procedure amongst major league baseball (MLB) pitchers. It is unclear if a limit on innings pitched following UCLR should be instituted to prevent revision UCLR. Purpose: To determine whether the number of innings pitched or number of pitches thrown in the first full season following UCLR, as well as the pitcher’s overall MLB career, correlated with need for a revision UCLR Hypothesis: Number of innings pitched and number of pitches thrown following UCLR will not affect whether a pitcher undergoes a revision UCLR. Methods: Methods: All MLB pitchers between 1974-2015 who pitched at least one full season following UCLR were included. Pitch counts and innings pitched for the first full season following UCLR as well as total pitch count and total innings pitched following UCLR were recorded. Pitch counts and innings pitched were compared amongst players who required revision UCLR and those who did not. Results: Results: Overall, 154 pitchers were included. Of these, 135 pitchers did not require revision UCLR while 19 underwent revision UCLR. No significant difference existed between pitchers who underwent revision UCLR and those who did not in: number of innings pitched in the season following UCLR (p=0.9016), number of pitches thrown in the season following UCLR (p=0.7337), number of innings pitched in the pitcher’s career following UCLR (p=0.6945), and number of pitches thrown in the pitcher’s career following UCLR (p=0.4789). Furthermore, no difference existed in revision rate between pitchers who pitched more or less than 180 innings in the first full season following UCLR (p=0.6678). Conclusion: Conclusion: The number of innings pitched and number of pitches thrown in the first full season as well as over a player’s career following UCLR does not appear to increase a player’s risk of revision UCLR.
Erne, Holger C; Zouzias, Ioannis C; Rosenwasser, Melvin P
Pitchers are prone to elbow injuries because of high and repetitive valgus stresses on the elbow. The anterior bundle of the medial ulnar collateral ligament (MCL) of the elbow is the primary restraint and is often attenuated with time, leading to functional incompetence and ultimate failure. Pitchers with a history of medial elbow pain, reduced velocity, and loss of command may have an MCL injury in evolution. Physical examination and imaging can confirm the diagnosis. Treatment begins with rest and activity modification. All medial elbow pain is not MCL injury. Surgery is considered only for talented athletes who wish to return to competitive play and may include elite scholastic and other collegiates and professionals. The technique for MCL reconstruction was first described in 1986. Many variations have been offered since then, which can result in predictable outcomes, allowing many to return to the same level of competitive play.
Oliver, Gretchen D; Weimar, Wendi H; Henning, Lisa E
It is generally accepted that playing with fatigue is a primary predictor of injury in youth baseball because muscular fatigue is believed to alter mechanics during the arm cocking and acceleration phases. Therefore, the purpose of this study was to quantitatively describe gluteal and upper extremity muscle activations in youth baseball pitchers during a simulated game. Twenty-three youth baseball players (11.2 ± 0.8 years; 151.4 ± 8.7 cm; 47.5 ± 10.8 kg) participated. Data were collected through a Delsys Bagnoli-8-channel electromyography system. Single differential electrodes (interelectrode distance: 10 mm) were attached to the bilateral gluteus maximus and medius and throwing side latissimus dorsi, lower trapezius, and serratus anterior and upper trapezius. After warm-up, participants were instructed to throw randomly provided game situations over a regulation distance (46 feet; 14.02 meters) to a catcher. Three, 4-seam fastballs for strikes, thrown in the first and last innings of the simulated game were selected for analysis. A multivariate analysis of variance revealed no statistically significant differences in muscle activity at the 3 phases of the throw, between first and last innings of the simulated game with an observed power of 0.274 (phase 1: foot contact to maximum shoulder external rotation), 0.297 (phase 2: maximum shoulder external rotation to ball release), and 0.226 (phase 3: ball release to maximum shoulder internal rotation). Examining muscle activations as a pitcher approaches fatigue provides information on how long a pitcher can perform before mechanical alterations occur. Although this study did not reveal significant changes, it did reiterate the fact that pitch counts may be working in possibly preventing a youth pitcher throwing to fatigue.
Wang, Lin-Hwa; Kuo, Li-Chieh; Shih, Sheng-Wen; Lo, Kuo-Cheng; Su, Fong-Chin
Previous research on baseball pitchers' wrists, elbows, and should joints contributes to our understanding of pitchers' control over delicate joint motion and ball release. However, limited research on forearm, wrist, and hand joints prevents full comprehension of the throwing mechanism. The present descriptive laboratory study quantifies angular performances of hand and wrist joints while pitching breaking balls, including fastballs, curveballs and sliders, among pitchers with different skill levels. Nineteen baseball pitchers performed required pitching tasks (10 from university and 9 from high school). A three-dimensional motion analysis system collected pitching motion data. The range of joint motion in the wrist and proximal interphalangeal (PIP) and metacarpophalangeal (MP) joints of the index and middle fingers were compared among fastballs, curveballs and sliders. Thirteen reflective markers were placed on selected anatomic landmarks of the wrist, middle and index fingers of the hand. Wrist flexion angle in the pitching acceleration phase was larger in fastballs (20.58±4.07°) and sliders (22.48±5.45°) than in curveballs (9.08±3.03°) (p = .001). The flexion angle of the PIP joint was significantly larger in curveballs (38.5±3.8°) than in fastballs (30.3±4.8°) and sliders (30.2±4.5°) (p=.004) of the middle finger. Abduction angle of MP joint on the middle finger was significantly larger in curveballs (15.4 ±3.6°) than in fastballs (8.9±1.2°) and sliders (6.9±2.9°) (p=.001) of the middle finger, and the abduction angle of index finger was significantly larger in sliders (13.5±15.0°) than in fastballs (7.2 ±2.8°) (p=.007). Hand and wrist motion and grip types affect the relative position between fingers and ball, which produces different types of baseball pitches. A larger extension angle of the wrist joint and the coordination of middle and index fingers are crucial when pitching a fastball. Abduction and flexion movement on the MP joint
Keeley, David W.; Oliver, Gretchen D.; Dougherty, Christopher P.
Previous work has postulated that shoulder pain may be associated with increases in both peak shoulder anterior force and peak shoulder proximal force. Unfortunately these relationships have yet to be quantified. Thus, the purpose of this study was to associate these kinetic values with reported shoulder pain in youth baseball pitchers. Nineteen healthy baseball pitchers participated in this study. Segment based reference systems and established calculations were utilized to identify peak shoulder anterior force and peak shoulder proximal force. A medical history questionnaire was utilized to identify shoulder pain. Following collection of these data, the strength of the relationships between both peak shoulder anterior force and peak shoulder proximal force and shoulder pain were analyzed. Although peak anterior force was not significantly correlated to shoulder pain, peak proximal force was. These results lead to the development of a single variable logistic regression model able to accurately predict 84.2% of all cases and 71.4% of shoulder pain cases. This model indicated that for every 1 N increase in peak proximal force, there was a corresponding 4.6% increase in the likelihood of shoulder pain. The magnitude of peak proximal force is both correlated to reported shoulder pain and capable of being used to accurately predict the likelihood of experiencing shoulder pain. It appears that those pitchers exhibiting high magnitudes of peak proximal force are significantly more likely to report experiencing shoulder pain than those who generate lower magnitudes of peak proximal force. PMID:23486209
Li, Xinning; Dines, Joshua S; Gorman, Matthew; Limpisvasti, Orr; Gambardella, Ralph; Yocum, Lou
Medial elbow pain is reported in 18% to 69% of baseball players aged of 9 and 19 years. This is due to the large valgus stresses focused on the medial side of the elbow during overhead activities. In overhead throwers and pitchers, pain can be attributed to valgus extension overload with resultant posteromedial impingement, overuse of the flexor-pronator musculature resulting in medial epicondylitis, or occasional muscle tears or ruptures. The anconeus epitrochlearis is a known cause of cubital tunnel syndrome and has been postulated as a source of medial elbow pain in overhead athletes. This article describes the cases of 3 right-handed baseball pitchers with persistent right-sided medial elbow pain during throwing despite a prolonged period of rest, physical therapy, and nonsteroidal anti-inflammatory drugs. Two patients had symptoms of cubital tunnel syndrome as diagnosed by electromyogram and nerve conduction studies and the presence of the anconeus epitrochlearis muscle per magnetic resonance imaging. All patients underwent isolated release of the anconeus muscle without ulnar nerve transposition and returned to their previous levels of activity. The diagnosis and treatment of pitchers who present with medial-sided elbow pain can be complex. The differential should include an enlarged or inflamed anconeus epitrochlearis muscle as a possible cause. Conservative management should be the first modality. However, surgical excision with isolated release of the muscle can be successful in returning patients with persistent pain despite a trial of conservative management to their previous levels of function.
Keeley, David W; Oliver, Gretchen D; Dougherty, Christopher P
Previous work has postulated that shoulder pain may be associated with increases in both peak shoulder anterior force and peak shoulder proximal force. Unfortunately these relationships have yet to be quantified. Thus, the purpose of this study was to associate these kinetic values with reported shoulder pain in youth baseball pitchers. Nineteen healthy baseball pitchers participated in this study. Segment based reference systems and established calculations were utilized to identify peak shoulder anterior force and peak shoulder proximal force. A medical history questionnaire was utilized to identify shoulder pain. Following collection of these data, the strength of the relationships between both peak shoulder anterior force and peak shoulder proximal force and shoulder pain were analyzed. Although peak anterior force was not significantly correlated to shoulder pain, peak proximal force was. These results lead to the development of a single variable logistic regression model able to accurately predict 84.2% of all cases and 71.4% of shoulder pain cases. This model indicated that for every 1 N increase in peak proximal force, there was a corresponding 4.6% increase in the likelihood of shoulder pain. The magnitude of peak proximal force is both correlated to reported shoulder pain and capable of being used to accurately predict the likelihood of experiencing shoulder pain. It appears that those pitchers exhibiting high magnitudes of peak proximal force are significantly more likely to report experiencing shoulder pain than those who generate lower magnitudes of peak proximal force.
Crawford, Scott D; Sauers, Eric L
Context: Repetitive overhead throwing has been theorized to result in chronic adaptations to the capsuloligamentous restraints of the glenohumeral joint. Objective: To compare glenohumeral joint laxity and stiffness between the throwing and nonthrowing shoulders of high school baseball pitchers. Design: Repeated measures. Setting: High school athletic training facilities. Patients or Other Participants: Twenty-two asymptomatic high school baseball pitchers (age = 16.50 ± 0.74 years, height = 178.51 ± 7.66 cm, mass = 75.43 ± 13.24 kg) from a sample of convenience. Main Outcomes Measure(s): We used computerized stress arthrometry to measure glenohumeral joint laxity and stiffness. Anterior glenohumeral joint laxity and stiffness measures were obtained with the shoulder in 90° of abduction and both neutral rotation and 90° of external rotation. Posterior laxity and stiffness measures were obtained with the shoulder in 90° of abduction and neutral rotation. Results: No clinically significant differences were found for glenohumeral laxity or stiffness between sides. However, a statistically significant main effect for position was present for both laxity and stiffness. Anterior glenohumeral joint laxity in the 90° external rotation position was significantly decreased and stiffness was increased in this position compared with the anterior at neutral and posterior at neutral positions. Conclusions: Glenohumeral joint laxity decreases and stiffness increases in the functional throwing position of 90° of abduction and 90° of external rotation. No clinically significant side-to-side differences or directional differences were found in high school baseball pitchers. PMID:16619095
Marshall, Nathan E.; Keller, Robert A.; Van Holsbeeck, Marnix; Moutzouros, Vasilios
Background: Baseball pitchers have adaptive changes in the soft tissues of the throwing elbow. Hypothesis: High school baseball pitchers would show adaptive changes in the ulnar collateral ligament (UCL), such as calcifications and hypoechoic foci, thickening, and increased ulnohumeral joint laxity, on dynamic ultrasound (DUS). Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: Twenty-two asymptomatic high school pitchers, designated as their primary position by their coach, underwent DUS and physical examination of the throwing and nonthrowing elbows prior to the start of the season. UCL substance consistency and thickness, ulnohumeral joint space widening, and soft tissue elbow structures were evaluated. Results: The mean age of the cohort was 16.9 years. Calcifications of the UCL were similar, being present in 7 of 22 (32%) throwing elbows versus 8 of 22 (36%) nonthrowing elbows (P = 0.11). UCL hypoechoic foci also were similar between elbows: 2 of 22 (9%) throwing elbows versus 0 of 22 nonthrowing elbows (P = 0.11). UCL thickness was also found to be similar in both elbows (throwing arm, 6.54 mm vs nonthrowing, 6.71 mm; P = 0.48). Ulnohumeral joint laxity unloaded (throwing arm, 3.13 mm vs nonthrowing, 3.17 mm; P = 0.835) and loaded (throwing arm, 3.87 mm vs nonthrowing arm, 4.11 mm; P = 0.30) was similar between elbows. Throwing elbows showed posteromedial olecranon spurring in 36%, effusions in 27%, and synovitis in 9%. Conclusion: High school pitchers show limited adaptive changes in the elbow, including UCL calcifications, hypoechoic foci, posteromedial olecranon spurring, and effusions. However, these changes are similar to those seen in the nonthrowing elbow, and these younger athletes lack findings seen in professional and collegiate pitchers such as UCL thickening and increased ulnohumeral joint space laxity. Clinical Relevance: Preseason ultrasound examination of the high school pitching elbow lacks the adaptive changes to the
Parks, Eric D.; Ray, Tracy R.
With millions of athletes participating in baseball in the United States annually, overuse injuries are common occurrences. Epidemiological studies, including surveys of orthopaedic surgeons, coaches, and athletes, indicate that injuries such as those to the ulnar collateral ligament are increasing in incidence. Many risk factors for throwing injuries have been proposed—including the immature skeleton, throwing mechanics, glenohumeral internal rotation deficit, pitch type, velocity, and counts—but little evidence is available to support the majority of these factors. Recent studies have shown that pitch volume and overuse are central factors that lead to shoulder and elbow injuries in the young throwing athlete. Pitching while fatigued and in spite of arm pain has also been implicated. PMID:23015915
Miniaci, Anthony; Mascia, Anthony T; Salonen, David C; Becker, Edna J
The purpose of this study was to evaluate the magnetic resonance imaging findings in both shoulders of asymptomatic professional baseball pitchers. Fourteen pitchers who were without significant prior injury underwent a blinded clinical assessment and magnetic resonance imaging of both shoulders. All images were interpreted by two experienced musculoskeletal radiologists. The appearance of the rotator cuff tendons was graded, with additional evaluation of the biceps, labrum, and osseous structures. Ten athletes were found to have stable shoulders and painless full range of motion. Clinically, four athletes had at least a 40 degrees loss in internal rotation as compared with the nonthrowing arm. There were no significant differences in magnetic resonance imaging findings of the supraspinatus and infraspinatus tendons between the throwing and nonthrowing shoulders. The labrum was abnormal in 79% of the 28 shoulders. Enthesopathic changes of the posterior glenoid labrum were identified in the four pitchers who had loss of internal rotation. We conclude that unenhanced magnetic resonance imaging of the shoulder in asymptomatic high performance throwing athletes reveals abnormalities that may encompass a spectrum of "nonclinical" findings. These data can be useful in separating symptomatic pathologic findings from these variants. Enthesopathic changes of the posterior glenoid labrum in the throwing arm may represent an early Bennett-type lesion. The cause may be excessive traction on the posterior capsule during the pitching motion, with subclinical injury to this area.
Grantham, W. Jeffrey; Byram, Ian R.; Meadows, Molly C.; Ahmad, Christopher S.
Background: Many factors are believed to contribute to throwing injuries in baseball pitchers, in particular overuse and poor throwing mechanics. The impact of fatigue on pitching biomechanics in live-game situations is not well understood. Hypothesis: Pitchers will demonstrate significant deviation in their pitching motions with increasing levels of fatigue. Study Design: Descriptive laboratory study. Methods: Eleven National Collegiate Athletic Association (NCAA) Division I collegiate baseball pitchers were filmed in multiple live-game situations throughout a single season using 2 orthogonal high-speed cameras at 120 Hz. The first fastball of each inning and, when available, the fastball subsequent to the 15th and 30th pitch of each inning were recorded and analyzed for 26 kinematic parameters. Pitch count and velocity were recorded. Kinematic differences were assessed for association with pitch count and subjective fatigue measures over the course of each inning and game through the season. Results: Twenty-six games were recorded. Pitchers had a mean of 97.2 ± 16.1 pitches per start and 1079 ± 251 pitches per collegiate season. Increased hip lean at hand separation, elbow height at foot contact, and hip flexion and shoulder tilt at maximum external rotation were seen in innings lasting longer than 15 pitches. Maximum external rotation of the shoulder and elbow height at foot contact decreased over the course of a game. Hip lean at hand separation and elbow height at foot contact increased over the course of the season. Season pitch count was weakly correlated with increased shoulder external rotation and shoulder alignment at maximum external rotation and with shoulder abduction at ball release. Elbow flexion decreased with greater season pitch counts. Conclusion: Hip lean, elbow height, and shoulder external rotation were the most sensitive kinematic parameters to inning, game, and season fatigue. Pitch count and fatigue have a significant impact on live
The shoulder of a non-throwing arm during a baseball pitch must be in a constant position while the shoulder of the throwing arm moves in a nearly circular path around it. However, it has not been investigated whether a skilled pitch requires less shoulder-joint movement. It was hypothesized that pitchers with less shoulder movement of the non-throwing arm can be considered to have higher skill and to attain higher initial ball velocity. Nine baseball pitchers were used as subjects. The coach classified them into a skilled and an unskilled group. The pitching motions were recorded using two high-speed cameras. The time series of three-dimensional landmark coordinates of the shoulder joint of the non-throwing arm during the baseball pitch were calculated using the direct linear transformation method. The shoulder-joint movement (SJM) index, which expresses the movement (displacement) of the shoulder joint of the non-throwing arm quantitatively, was proposed to compare the SJM at different skill levels and investigate the relationship between SJM and initial ball velocity. The SJM of the skilled pitchers was smaller than that of the unskilled pitchers, and the smaller value of the SJM led to faster initial ball velocity. The data suggest that the less SJM of the non-throwing arm is required to attain a skilled pitch and higher initial ball velocity.
Sakata, Takeshi; Kimura, Yasunobu; Hida, Toshiko
Stress fractures of the first rib in athletes are rare. A 14-year-old male, a baseball pitcher who changed from an overhand to a sidearm style, with a stress fracture of the first rib, was reported. Most Stress fractures in the first rib occur at the subclavian groove, between the attachments of the scalenus anterior and scalenus medius muscles, which is the thinnest and weakest portion of the rib. However, in this case the stress fracture occurred at the uncommon region, posterior to the insertion of the scalenus medius muscle, in the first rib. The motion analysis of the pitching in this case demonstrated that the sidearm style induced much more horizontal abduction in the shoulder at the top position than did the overhand style. The findings of electromyography in the serratus anterior muscle, one of the muscles which insert on the first rib, through the pitching motion did not demonstrate any significant differences between the two styles. In this case, the repetition of horizontal over-abduction of the shoulder when sidearm pitching appears to have been the cause of the unusual stress fracture of the first rib at this site. Key Points Most Stress fractures in the first rib occur at the subclavian groove, between the attachments of the scalenus anterior and scalenus medius muscles, which is the thinnest and weakest portion of the rib. We report the case of a young male baseball pitcher with a stress fracture of the first rib located uncommonly at the posterior portion of the rib. In this case, the repetition of horizontal over-abduction of the shoulder when sidearm pitching appears to have been the cause of the unusual stress fracture of the first rib at this site. PMID:24431977
Solomito, Matthew J; Garibay, Erin J; Woods, Jessica R; Ounpuu, Sylvia; Nissen, Carl W
Current pitching literature focuses primarily on the elbow and glenohumeral joints. This has led to a paucity of information regarding the forearm and wrist, and the limited data available are inconsistent. Therefore, this article seeks to provide a comprehensive description of the kinematics and kinetics of the wrist and forearm for the fastball, curveball, slider/cutter, and change-up for college-level baseball pitchers. Thirty-six collegiate pitchers were evaluated using motion analysis techniques. Results indicated that pitching the curveball generated the greatest forearm supination (16 ± 13°) compared with the other three pitch types (p < 0.05). The curveball and slider/cutter were pitched with less wrist extension and greater ulnar deviation compared with the fastball and change-up. The curveball was found to produce the greatest ulnar moment (7.3 ± 2.2 Nm) and was significantly different from the moments noted when pitching the fastball and change-up (5.1 ± 1.9 and 4.9 ± 1.9 Nm, respectively; p < 0.05). These results indicate that it may be possible to objectively determine pitch type from kinematic data of the wrist and forearm. It may also be possible that coaches may be able to identify abnormal pitching mechanics from more proximal segments by understanding the motion of the wrist.
Oliver, Gretchen D; Keeley, David W
It was the purpose of our study to examine the kinematics of the pelvis and torso and determine their relationship to the kinematics of the shoulder in high-school baseball pitchers. A single group, repeated-measures design was used to collect pelvis, torso, and shoulder kinematics throughout the pitching motion. Subjects threw a series of maximal effort fastballs to a catcher located the regulation distance (18.44m) from the pitching mound, and those data from the fastest pitch passing through the strike zone were analyzed. After test trials, kinematic data were analyzed using a series of descriptive statistics to identify outliers and determine the nature of the distribution before testing for the presence of relationships between the various parameters. Results indicated that for several parameters, the actions at and about the shoulder are strongly related to the actions of the pelvis and torso throughout the pitching motion. However, although pelvis and torso kinematics throughout the pitching motion were inversely related to both shoulder elevation and the plane of shoulder elevation, only the rate of axial torso rotation was significantly related to these shoulder parameters. More importantly, the rate of axial torso rotation is significantly related to these shoulder parameters in a way that may help explain the high rate of shoulder injury in high-school pitchers. Therefore, strength training should focus on developing a strong stable core including the gluteal musculature in an attempt to control the rate of torso rotation during the pitch.
Kato, Kinshi; Yabuki, Shoji; Otani, Koji; Nikaido, Takuya; Otoshi, Ken-ichi; Watanabe, Kazuyuki; Kikuchi, Shin-ichi; Konno, Shin-ichi
Abstract Symptomatic thoracic disc herniation is clinically rare. There are few cases of disc herniation of the thoracic spine in top athletes described in the literature. We herein present a rare case of chest wall pain due to thoracic disc herniation in a professional baseball pitcher. A 30-year-old, left-handed pitcher complained of left-sided chest wall pain in the region of his lower ribs during a game. Neurological examination revealed hypoesthesia of the left side of the chest at the level of the lower thoracic spine. Magnetic resonance imaging (MRI) of the thoracic spine showed a left-sided paramedian disc herniation at the T9-T10 level. The player was initially prescribed rest, administration of pregabalin (150 mg twice a day), and subsequent physical rehabilitation. He was able to resume full training and pitching without medication 6 months after the onset. A follow-up MRI of the thoracic spine showed a reduction in the size of the herniated disc compared to the initial findings. Though relatively rare, thoracic disc herniation should be considered in cases of chest wall pain in athletes. PMID:26983590
Douoguih, Wiemi A.; Dolce, Donald L.; Lincoln, Andrew E.
Background: Early cocking phase pitching mechanics may affect risk of upper extremity injury requiring surgery in professional baseball players. Purpose: To assess the occurrence of inverted-W arm positioning and early trunk rotation in Major League Baseball (MLB) pitchers and to determine whether this throwing position is associated with upper extremity injury requiring surgery. Study Design: Cross-sectional study; Level of evidence, 3. Methods: For 250 MLB pitchers in the 2010 season, 15 to 20 pitches from the start and end of an outing were reviewed using slow-motion game video for presence of an inverted-W position and early trunk rotation. Previous or current incidence of upper extremity injury requiring surgery for each player was determined using the MLB injury database, minor league injury records, available collegiate data, and publicly available online injury databases. Upper extremity surgery associated with an injury was considered to result from pitching. Results: Consensus between investigators was achieved for 99% of players for inverted-W positioning (248 players) and in 97% of players for early trunk rotation (243 players) for videos reviewed independently. Rate of surgery with and without inverted-W position was 28 of 93 (30%) and 42 of 155 (27%), respectively. Rate of surgery with and without early trunk rotation was 37 of 111 (33%) and 30 of 132 (23%), respectively. Using a Cox proportional hazards model for risk analysis using the measured number of innings pitched at time of surgery as an approximate index of exposure and adjusting for age and fastball speed at time of surgery, early trunk rotation was associated with significantly increased risk of shoulder and/or elbow surgery with hazard ratio estimate of 1.69 (95% CI, 1.02-2.80). Presence of the inverted-W position was not associated with significantly increased risk (hazard ratio, 1.30; 95% CI, 0.79-2.14). Conclusion: The inverted-W throwing position was not associated with significantly
Potteiger, Jeffrey A.; Blessing, Daniel L.; Wilson, G. Dennis
In this study we examined the effects of varied recovery time on serum creatine kinase (CK), serum lactate dehydrogenase (LDH), muscle soreness, and pitch velocity in baseball pitchers. Ten males who had pitching experience participated in the study. After an 18-day training period, subjects pitched three simulated games. Game A and Game B were separated by four days of rest, while Game B and Game C were separated by two days of rest. CK, LDH, and muscle soreness were evaluated at the following times: before and immediately after exercise, and six, 24, 48, and 72 hours after exercise. Muscle performance was evaluated by measuring pitch velocity during the games. The CK level was elevated after each game (Game A - 249 U/l; Game B - 243 U/l; and Game C - 240 U/l); then it dropped toward baseline (p≤0.01). CK post-exercise values were not different among games A, B, and C. LDH displayed a response similar to CK; however, there was a reduction over the span of the games (p≤0.05). Muscle soreness was significantly elevated immediately after exercise (p≤0.01) compared to all other measurement times. Pitch velocity was not different among games A, B, and C. Results indicate that muscle damage, as evidenced by CK release, occurs in response to baseball pitching. However CK values, muscle soreness, and pitch velocity are not significantly affected by changes in the amount of recovery time typically scheduled between games. PMID:16558126
Post, Eric G.; Laudner, Kevin G.; McLoda, Todd A.; Wong, Regan; Meister, Keith
Context Throwing a baseball is a dynamic and violent act that places large magnitudes of stress on the shoulder and elbow. Specific injuries at the elbow and glenohumeral joints have been linked to several kinetic variables throughout the throwing motion. However, very little research has directly examined the relationship between these kinetic variables and ball velocity. Objective To examine the correlation of peak ball velocity with elbow-valgus torque, shoulder external-rotation torque, and shoulder-distraction force in a group of collegiate baseball pitchers. Design Cross-sectional study. Setting Motion-analysis laboratory. Patients or Other Participants Sixty-seven asymptomatic National Collegiate Athletic Association Division I baseball pitchers (age = 19.5 ± 1.2 years, height = 186.2 ± 5.7 cm, mass = 86.7 ± 7.0 kg; 48 right handed, 19 left handed). Main Outcome Measure(s) We measured peak ball velocity using a radar gun and shoulder and elbow kinetics of the throwing arm using 8 electronically synchronized, high-speed digital cameras. We placed 26 reflective markers on anatomical landmarks of each participant to track 3-dimensional coordinate data. The average data from the 3 highest-velocity fastballs thrown for strikes were used for data analysis. We calculated a Pearson correlation coefficient to determine the associations between ball velocity and peak elbow-valgus torque, shoulder-distraction force, and shoulder external-rotation torque (P < .05). Results A weak positive correlation was found between ball velocity and shoulder-distraction force (r = 0.257; 95% confidence interval [CI] = 0.02, 0.47; r2 = 0.066; P = .018). However, no significant correlations were noted between ball velocity and elbow-valgus torque (r = 0.199; 95% CI = −0.043, 0.419; r2 = 0.040; P = .053) or shoulder external-rotation torque (r = 0.097; 95% CI = −0.147, 0.329; r2 = 0.009; P = .217). Conclusions Although a weak positive correlation was present between ball velocity
Vad, Vijay B; Cano, William G; Basrai, Dilshaad; Lutz, Gregory E; Bhat, Atul L
Lumbar zygapophyseal joints have long been considered a source of low back pain with or without leg pain. The objective of this prospective study was to investigate the therapeutic effectiveness of lumbar zygapophyseal joint radiofrequency denervation (RFD) followed by physical therapy, for the treatment of refractory lumbar zygapophyseal joint mediated low back pain secondary to lumbar zygapophyseal joint synovitis, in baseball pitchers. Participants included twelve male baseball pitchers with a diagnosis of lumbar zygapophyseal joint synovitis mediated low back pain and a subsequent difficulty in pitching. These athletes underwent a trial of treatment, including oral anti-inflammatory medication, physical therapy, osteopathic manipulations, and fluoroscopically guided intra-articular zygapophyseal joint injection utilizing steroid and local anesthetic agent. Failure to progress led to these athletes receiving percutaneous, fluoroscopically-guided, radiofrequency denervation of the bilateral L 4-L5 and L5-S1 zygapophyseal joints. A good response to a diagnostic medial branch block was a prerequisite for RFD treatment. In all cases, the medial branch above and below the involved level was treated. Post procedure, all athletes participated in a phased physical therapy program followed by a progressive return to pitching. Success was defined as the ability to return to pre-procedure level of baseball pitching combined with greater than 50% low back pain reduction. Pre- and post-RFD, Visual Analog (Numeric) Scale (VAS) and Roland-Morris (R-M) tests were administered. Ten out of 12 (83%) athletes were able to return to pitching at a level attained prior to RFD. All 12 patients, experienced statistically significant low back pain relief, with a mean pre-RFD VAS of 8.4; mean post-RFD VAS of 1.7; mean pre-RFD R-M score of 12.3; and mean post-RFD R-M score of 22.3. In conclusion, athletes, experiencing lumbar zygapophyseal joint mediated low back pain secondary to
McNally, Michael P; Borstad, John D; Oñate, James A; Chaudhari, Ajit M W
Ground reaction forces produced during baseball pitching have a significant impact in the development of ball velocity. However, the measurement of only one leg and small sample sizes in these studies curb the understanding of ground reaction forces as they relate to pitching. This study aimed to further clarify the role ground reaction forces play in developing pitching velocity. Eighteen former competitive baseball players with previous high school or collegiate pitching experience threw 15 fastballs from a pitcher's mound instrumented to measure ground reaction forces under both the drive and stride legs. Peak ground reaction forces were recorded during each phase of the pitching cycle, between peak knee height and ball release, in the medial/lateral, anterior/posterior, and vertical directions, and the peak resultant ground reaction force. Stride leg ground reaction forces during the arm-cocking and arm-acceleration phases were strongly correlated with ball velocity (r2 = 0.45-0.61), whereas drive leg ground reaction forces showed no significant correlations. Stepwise linear regression analysis found that peak stride leg ground reaction force during the arm-cocking phase was the best predictor of ball velocity (r2 = 0.61) among drive and stride leg ground reaction forces. This study demonstrates the importance of ground reaction force development in pitching, with stride leg forces being strongly predictive of ball velocity. Further research is needed to further clarify the role of ground reaction forces in pitching and to develop training programs designed to improve upper extremity mechanics and pitching performance through effective force development.
Brucker, Jason; Sahu, Novneet; Sandella, Bradley
Upper extremity stress fractures, which are relatively rare, have become increasingly common, with olecranon stress injuries representing a subset primarily affecting throwing athletes. Olecranon stress fractures have been classified to fit specific radiographic patterns, with most of these injuries typified by a fracture line. Only a handful of olecranon stress injury cases report magnetic resonance imaging findings of osseous edema within the olecranon, as in our case of a 17-year-old competitive overhand baseball pitcher with elbow pain. The patient was treated conservatively and had resolution of pain after 6 weeks of rest, followed by a 6-week throwing progression with full return to pitching. PMID:26137175
Hoffman, James K.; Protzman, Nicole M.; Malhotra, Amit D.
Tears of the ulnar collateral ligament (UCL) of the elbow are common injuries in overhead athletes. Although surgical reconstruction of the UCL has improved outcomes, not all athletes return to their previous level of competition and when this goal is achieved, the time required averages one to two years. Therefore, additional techniques are needed to further improve return to play and the rate of return to play in overhead athletes. A construct comprising a dermal allograft, platelet rich plasma (PRP), and mesenchymal stem cells (MSCs) has been shown to successfully improve healing in the rotator cuff. Given the promising provisional findings, we postulated that this construct could also improve healing if applied to the UCL. Therefore, the purpose of the present report was to examine the feasibility of utilizing a dermal allograft, PRP, and MSC construct to augment UCL reconstruction in a professional baseball pitcher. No complications were encountered. Although limited to minimal follow-up, the patient has demonstrated excellent progress and has returned to activity. PMID:26240769
Bradbury, John C; Forman, Sean L
Although the belief that overuse can harm pitchers is widespread, there exists little evidence to show that the number of pitches thrown and the days of rest affect future performance and injury among adults. The purpose of this study is to quantify the effects of pitches thrown and the days of rest on pitcher performance. We examined performances of major-league baseball starting pitchers from 1988 to 2009 using fractional polynomial multiple regression to estimate the immediate and cumulative impact of pitches thrown and the days of rest on performance, while controlling for other factors that likely affect pitcher effectiveness. Estimates indicate each pitch thrown in the preceding game increased earned run average (ERA) by 0.007 in the following game. Each pitch averaged in the preceding 5 and 10 games increased the ERA by 0.014 and 0.022, respectively. Older pitchers were more sensitive to cumulative pitching loads than younger pitchers were, but they were less affected by pitches thrown in the preceding game. Rest days were weakly associated with performance. In summary, we found that there is a negative relationship between past pitches thrown and future performance that is virtually linear. The impact of the cumulative pitching load is larger than the impact of a single game. Rest days do not appear to have a large impact on performance. This study supports the popular notion that high pitching loads can dampen future performance; however, because the effect is small, pitch-count benchmarks have limited use for maintaining performance and possibly preventing injury.
Smith, Ryan; Lombardo, Daniel J.; Petersen-Fitts, Graysen R.; Frank, Charles; Tenbrunsel, Troy; Curtis, Gannon; Whaley, James; Sabesan, Vani J.
Background: The published return-to-play (RTP) rates for Major League Baseball (MLB) pitchers who have undergone surgical repair of superior labrum anterior-posterior (SLAP) tears vary widely and are generally accepted to be lower in the subset of competitive throwers. The efficacy of surgical treatment for MLB players is largely unknown. Purpose: To examine the RTP rate and performance of MLB pitchers who have undergone SLAP tear repair between 2003 and 2010. Study Design: Descriptive epidemiological study. Methods: A retrospective review of MLB pitchers undergoing SLAP repair was performed using the MLB disabled list. Data collected included the following player statistics: earned run average (ERA), walks plus hits per inning pitched (WHIP), and innings pitched (IP). The mean values for performance variables both before and after surgery were compared. A definition of return to prior performance (RTPP) was established as an ERA within 2.00 and WHIP within 0.500 of preoperative values. Results: Twenty-four MLB players met inclusion criteria, of which 62.5% were able to RTP at the MLB level after SLAP repair surgery. Of those able to RTP, 86.7% were able to RTPP. However, the overall rate of RTPP, including those unable to RTP, was 54.2%. Mean performance analysis of the RTP group revealed a statistically significant decrease in IP for MLB pitchers throwing a mean 101.8 innings before injury and 65.53 innings after injury (P = .004). Conclusion: Of those pitchers able to RTP, chances of a full recovery were good (86.7%). Our results indicate the need for future research aimed at proper surgical selection of who will return to play, as they will likely achieve full recovery. We believe this information can help surgeons advise high-level overhead-throwing athletes about expected outcomes for surgical treatment of SLAP tears. PMID:28203588
Hurd, Wendy J.; Jazayeri, Reza; Mohr, Karen; Limpisvasti, Orr; ElAttrache, Neal S.; Kaufman, Kenton R.
Background: Medial elbow injuries are common among baseball pitchers. Easily accessed methods to assess medial elbow stress may be useful in identifying individuals with increased injury risk. Hypothesis: Pitch velocity (PV) is positively associated with higher medial elbow adduction moments. Study Design: Cohort study; Level of evidence, 2. Methods: Participants included 26 uninjured high school pitchers, 15 to 18 years in age. Three-dimensional data and PV were collected as athletes threw 10 fastballs for strikes to a regulation-distance target. Variables of interest were the normalized peak internal elbow adduction moment and peak PV. Linear regression was performed to evaluate the influence of PV on the adduction moment. Results: For the group, mean PV was 71 mph (range, 58-81 mph), and the adduction moment was 0.558 Nm/Ht × mass (range, 0.378-0.723). PV was positively associated with the adduction moment (P < 0.01, R2= 0.373). Conclusions: Talented young pitchers may be more susceptible to elbow injuries as a consequence of a biomechanical coupling between PV and upper extremity joint moments. Clinical Relevance: PV may be measured easily and serve as an indicator of medial elbow stress. PMID:23016114
Lynch, Thomas Sean; Frangiamore, Salvatore; Vaughn, Michael Derek; Soloff, Lonnie; Schickendantz, Mark S.
Objectives: Ulnar collateral injuries (UCL) of the elbow are prevalent among professional baseball pitchers. The decision on initial operative versus nonoperative management of these injuries remains subjective in many cases, with reported success rates with nonoperative management ranging from 42 to 93% in professional throwing athletes. No studies to date have identified objective characteristics specific to success or failure of nonoperative intervention. The purpose of this study was to identify radiologic predictors for success or failure in nonoperative management of ulnar collateral ligament injuries in professional pitchers. Methods: A retrospective review of pitchers sustaining UCL injuries between 2006 and 2015 from one professional baseball organization (one major league team and all minor league teams included) was performed. UCL injuries were identified in 38 players based on clinical and radiographic findings. Six players underwent initial surgical intervention without attempted nonoperative intervention and were excluded from analysis. This left 32 (84%) professional pitchers who underwent an initial trail of nonoperative treatment for partial UCL tears. Success was defined as return to same level of play (RTSP) or higher for >1 year. Failure was defined as recurrent pain or weakness requiring surgical intervention after a minimum of 3 months’ rest when attempting a return to throw rehabilitation program. MRI findings were classified as high or low grade sprains, proximal or distal location of injury, and with or without the presence of concomitant chronic findings. Results: Of the 32 patients who underwent nonoperative management, 10 (36%) failed and required subsequent ligament reconstruction. Between the success and failure groups, there was no significant difference seen in total shoulder arc of motion (P=.7776), shoulder internal rotation deficit (P=.3846) or loss in elbow extension (P=.0644) at the time of injury. When comparing MRI findings
Hurd, Wendy J.; Kaplan, Kevin M.; ElAttrache, Neal S.; Jobe, Frank W.; Morrey, Bernard F.; Kaufman, Kenton R.
Context: The magnitude of motion that is normal for the throwing shoulder in uninjured baseball pitchers has not been established. Chronologic factors contributing to adaptations in motion present in the thrower's shoulder also have not been established. Objectives: To develop a normative profile of glenohumeral rotation motion in uninjured high school baseball pitchers and to evaluate the effect of chronologic characteristics on the development of adaptations in shoulder rotation motion. Design: Cohort study. Setting: Baseball playing field. Patients or Other Participants: A total of 210 uninjured male high school baseball pitchers (age = 16±1.1 years, height = 1.8 + 0.1 m, mass = 77.5±11.2 kg, pitching experience = 6±2.3 years). Intervention(s): Using standard goniometric techniques, we measured passive rotational glenohumeral range of motion bilaterally with participants in the supine position. Main Outcome Measure(s): Paired t tests were performed to identify differences in motion between limbs for the group. Analysis of variance and post hoc Tukey tests were conducted to identify differences in motion by age. Linear regressions were performed to determine the influence of chronologic factors on limb motion. Results: Rotation motion characteristics for the population were established. We found no difference between sides for external rotation (ER) at 0° of abduction (t209 = 0.658, P = .51), but we found side-to-side differences in ER (t209 = −13.012, P<.001) and internal rotation (t209 = 15.304, P<.001) at 90° of abduction. Age at the time of testing was a significant negative predictor of ER motion for the dominant shoulder (R2 = 0.019, P = .049) because less ER motion occurred at the dominant shoulder with advancing age. We found no differences in rotation motion in the dominant shoulder across ages (F4,205 range, 0.451–1.730, P>.05). Conclusions: This range-of-motion profile might be used to assist with the interpretation of normal and atypical
Dines, Joshua S; Jones, Kristofer; Maher, Patrick; Altchek, David
Clinical outcomes of surgical management of full-thickness rotator cuff tears in professional baseball players have been uniformly poor. We conducted a study to investigate return-to-play data and functional performance using a novel arthroscopic repair technique. We hypothesized that arthroscopic rotator cuff repair would result in a high rate of return to professional pitching and favorable functional outcomes. We identified 6 consecutive Major League Baseball (MLB) pitchers who underwent surgical repair of full-thickness rotator cuff injuries using the lateralized footprint repair technique. At most recent follow-up, patients were evaluated to determine their ability to return to athletic activity. Functional outcomes were also assessed using player performance statistics. By mean follow-up of 66.7 months (range, 23.2-94.6 months), 5 (83%) of the 6 pitchers had returned to their preinjury level of competition for at least 1 full season. Despite the high rate of return to MLB play, few pitchers resumed pitching productivity at their preoperative level; mean number of innings pitched decreased from 1806.5 to 183.7. A slight performance reduction was also found in a comparison of preoperative and postoperative pitching statistics. Of note, the return rate was higher for players over age 30 years than for those under 30 years. Overhead athletes require a delicate balance of shoulder mobility and stability to meet functional demands. Anatomical adaptations at the glenohumeral joint should be considered when performing rotator cuff repair in these patients in order to preserve peak functional performance. This novel repair technique affords a high rate of return to MLB play, though elite overhead throwers should be counseled that pitching productivity might decrease after surgery.
Tanaka, Hiroshi; Hayashi, Toyohiko; Inui, Hiroaki; Ninomiya, Hiroki; Muto, Tomoyuki; Nobuhara, Katsuya
Objectives: Shoulder and elbow pain in youth baseball pitchers is a well-recognized phenomenon. Common problems in pitching mechanics that can lead to injury begin with stride foot contact. The purpose of this study was to address the relationships between the combinations of shoulder, elbow and trunk orientation at the instant of stride foot contact and elbow joint loads in youth baseball pitchers. Methods: A total of 143 Japanese male youth baseball pitchers participated in this study after providing written informed consents approved by the hospital’s institutional review board. The procedures to be performed were also explained to their parent(s) or legal guardian(s). Each participant was not currently injured or recovering from an injury at time of testing. For data collection of baseball pitching, a set of 14-mm spherical reflective markers was placed on the skin overlying 34 anatomical landmarks determined. Subsequently, a motion capture three-dimensional automatic digitizing system was used to collect 500-Hz from 7 charge-coupled-device synchronized cameras was set up around the regulation pitching mound in an indoor laboratory. After performing a preparation routine of stretching and warm-up pitching, each player pitch to 5 fastball pitches off the pitching mound to a catcher at the regulation distance of 16 m for youth pitchers. The best pitch thrown for a strike was chosen for kinematic and kinetic analysis. The local coordinate systems were used to calculate 3-dimesional rotation at the trunk, shoulder and elbow using the typical Eulerian sequence. Afterward, the standard inverse dynamic equation was used to estimate resultant joint forces and torques at throwing shoulder and elbow. In order to normalize data between subjects, forces and torques were expressed as percent using body weight and height. A multiple regression analysis was carried out to assess the combined effects of shoulder (external rotation, abduction and horizontal adduction), elbow
Domes, Christopher M; Petering, Ryan C; Chesnutt, James C; Mirarchi, Adam
Little leaguer's elbow and Little leaguer's shoulder are overuse pathologies seen in overhead-throwing athletes. No instance of simultaneously occurring pathologies has been published. A 15-year-old baseball pitcher and football quarterback developed pain in his throwing shoulder and elbow during spring baseball, which partially resolved with several months of rest. During fall football practice, he felt a pop and pain over his medial throwing elbow. Five days after the initial injury, medial elbow tenderness, mild swelling, and decreased range of motion were noted. Radiographs revealed a Salter I avulsion fracture of the medial humeral epicondyle (Little leaguer's elbow) and a periosteal reaction along the lateral aspect of the humeral metadiaphysis with slight widening (Little leaguer's shoulder). Surgical fixation of the medial epicondyle fracture and nonoperative treatment of the shoulder pathology were performed. Two-year follow-up radiographs showed a healed medial epicondylar fracture and resolution of the periosteal reaction of the humeral metadiaphysis. The patient returned to full activity and was starting quarterback for his football team. Biomechanical forces specific to overhead-throwing activities are associated with the development of Little leaguer's elbow and shoulder. Treatments of both pathologies remain controversial, with either initial operative vs nonoperative care. In this patient, a good outcome was achieved with surgical fixation of the elbow fracture and conservative management of the shoulder pathology. Educating coaches and parents on proper throwing technique and pitching limits should be the first step in reducing the occurrence of either pathology in this population.
Milewski, Matthew D; Õunpuu, Sylvia; Solomito, Matthew; Westwell, Melany; Nissen, Carl W
Documentation of the lower extremity motion patterns of adolescent pitchers is an important part of understanding the pitching motion and the implication of lower extremity technique on upper extremity loads, injury and performance. The purpose of this study was to take the initial step in this process by documenting the biomechanics of the lower extremities during the pitching cycle in adolescent pitchers and to compare these findings with the published data for older pitchers. Three-dimensional motion analysis using a comprehensive lower extremity model was used to evaluate the fast ball pitch technique in adolescent pitchers. Thirty-two pitchers with a mean age of 12.4 years (range 10.5-14.7 years) and at least 2 years of experience were included in this study. The pitchers showed a mean of 49 ± 12° of knee flexion of the lead leg at foot contact. They tended to maintain this position through ball release, and then extended their knee during the follow through phase (ball release to maximal internal glenohumeral rotation). The lead leg hip rapidly progressed into adduction and flexion during the arm cocking phase with a range of motion of 40 ± 10° adduction and 30 ± 13° flexion. The lead hip mean peak adduction velocity was 434 ± 83°/s and flexion velocity was 456 ± 156°/s. Simultaneously, the trailing leg hip rapidly extended approaching to a mean peak extension of -8 ± 5° at 39% of the pitch cycle, which is close to passive range of motion constraints. Peak hip abduction of the trailing leg at foot contact was -31 ± 12°, which also approached passive range of motion constraints. Differences and similarities were also noted between the adolescent lower extremity kinematics and adult pitchers; however, a more comprehensive analysis using similar methods is needed for a complete comparison.
Oliver, Gretchen D; Keeley, David W
The purpose of this study was to examine the activation patterns of the gluteal muscle group and their relationship to pelvis and torso kinematics throughout the high-school pitching motion. A single group, repeated-measures design was used to collect gluteus maximus and gluteus medius muscle activity through surface electromyography for the preferred and nonpreferred sides during the various phases of the pitching motion. In addition, data describing the kinematics of the pelvis and torso were collected at foot contact, maximum shoulder external rotation, ball release, and maximum shoulder internal rotation. For all pitchers, preferred gluteus maximus activity was observed to be in excess of 100% of their maximum voluntary isometric contraction throughout the stride and arm-cocking phases of the pitching motion. The observed means for the preferred gluteus medius, nonpreferred gluteus maximus, and nonpreferred gluteus medius, although different in magnitude, were similar in pattern. From the conclusion of the stride phase, through the conclusion of the arm-cocking phase, muscle activity increased for all pitchers. In examining the relationship between the rate of axial pelvis rotation and gluteal activity, several significant relationships were observed. In contrast, no significant relationships were observed with gluteal activity parameters and the rate of axial torso rotation. However, because the pitching motion progresses sequentially from the pelvis to the torso, variability in pelvis rotation may be directly related to variability in torso rotation. The findings from this study indicate that during the baseball pitch, there is a need for greater control of gluteal activation throughout the pitching motion.
Warren, Courtney D; Szymanski, David J; Landers, Merrill R
Baseball pitching has been described as an anaerobic activity from a bioenergetics standpoint with short bouts of recovery. Depending on the physical conditioning and muscle fiber composition of the pitcher as well as the number of pitches thrown per inning and per game, there is the possibility of pitchers fatiguing during a game, which could lead to a decrease in pitching performance. Therefore, the purpose of this study was to evaluate the effects of 3 recovery protocols: passive recovery, active recovery (AR), and electrical muscle stimulation (EMS) on range of motion (ROM), heart rate (HR), rating of perceived exertion (RPE), and blood lactate concentration in baseball pitchers during a simulated game. Twenty-one Division I intercollegiate baseball pitchers (age = 20.4 ± 1.4 years; height = 185.9 ± 8.4 cm; weight = 86.5 ± 8.9 kg; percent body fat = 11.2 ± 2.6) volunteered to pitch 3 simulated 5-inning games, with a maximum of 70 fastballs thrown per game while wearing an HR monitor. Range of motion was measured pre, post, and 24 hours postpitching for shoulder internal and external rotation at 90° and elbow flexion and extension. Heart rate was recorded after each pitch and after every 30 seconds of the 6-minute recovery period. Rating of perceived exertion was recorded after the last pitch of each inning and after completing each 6-minute recovery period. Immediately after throwing the last pitch of each inning, postpitching blood lactate concentration (PPLa-) was measured. At the end of the 6-minute recovery period, before the next inning started, postrecovery blood lactate concentration (PRLa-) was measured. Pitchers were instructed to throw each pitch at or above 95% of their best-pitched fastball. This was enforced to ensure that each pitcher was throwing close to maximal effort for all 3 simulated games. All data presented represent group mean values. Results revealed that the method of recovery protocol did not significantly influence ROM (p > 0
Chen, Hsiu-Hui; Liu, Chiang; Yang, Wen-Wen
This study compared the whole-body movement coordination of pitching among 72 baseball players of various ages and velocity levels. Participants were classified as senior, junior, and little according to their age, with each group comprising 24 players. The velocity levels of the high-velocity (the top eight) and low-velocity (the lowest eight) groups were classified according to their pitching velocity. During pitching, the coordinates of 15 markers attached to the major joints of the whole-body movement system were collected for analysis. Sixteen kinematic parameters were calculated to compare the groups and velocity levels. Principal component analysis (PCA) was conducted to quantify the coordination pattern of pitching movement. The results were as follows: (1) five position and two velocity parameters significantly differed among the age groups, and two position and one velocity parameters significantly differed between the high- and low-velocity groups. (2) The coordination patterns of pitching movement could be described using three components, of which the eigenvalues and contents varied according to age and velocity level. In conclusion, the senior and junior players showed greater elbow angular velocity, whereas the little players exhibited a wider shoulder angle only at the beginning of pitching. The players with high velocity exhibited higher trunk and shoulder rotation velocity. The variations among groups found using PCA and kinematics parameter analyses were consistent.
Shannon, John, Ed.
This student newsletter issue speaks to the subject of baseball. The first article, on who rules baseball, discusses the problems that the developing sport had with gambling, and the struggle between the owners and gangsters for control of the game. The article describes the scandal involving the Chicago White Sox in the 1919 World Series and the…
Robb, Andrew; Sajko, Sandy
This report documents retrospectively a case of Posterior Interosseous Neuropathy (PIN) occurring in an elite baseball pitcher experiencing a deep ache in the radial aspect of the forearm and altered sensation in the dorsum of the hand on the throwing arm during his pitching motion. The initial clinical goal was to control for inflammation to the nerve and muscle with active rest, microcurrent therapy, low-level laser therapy, and cessation of throwing. Minimizing mechanosensitivity at the common extensor region of the right elbow and PIN, was achieved by employing the use of myofascial release and augmented soft tissue mobilization techniques. Neurodynamic mobilization technique was also administered to improve neural function. Implementation of a sport specific protocol for the purposes of maintaining throwing mechanics and overall conditioning was utilized. Successful resolution of symptomatology and return to pre-injury status was achieved in 5 weeks. A review of literature and an evidence-based discussion for the differential diagnoses, clinical examination, diagnosis, management and rehabilitation of PIN is presented.
Yang, Wen-Wen; Liu, Ya-Chen; Lu, Lee-Chang; Chang, Hsiao-Yun; Chou, Paul Pei-Hsi; Liu, Chiang
Compared with regulation-weight baseballs, lightweight baseballs generate lower torque on the shoulder and elbow joints without altering the pitching movement and timing. This study investigates the throwing accuracy, throwing velocity, arm swing velocity, and maximum shoulder external rotation (MSER) of adolescent players after 10 weeks of pitching training with appropriate lightweight baseballs. We assigned 24 adolescent players to a lightweight baseball group (group L) and a regulation-weight baseball group (group R) based on their pretraining throwing velocity. Both groups received pitching training 3 times per week for 10 weeks with 4.4- and 5-oz baseballs. The players' throwing accuracy, throwing velocity, arm swing velocity, and MSER were measured from 10 maximum efforts throws using a regulation-weight baseball before and after undergoing the pitching training. The results showed that the players in group L significantly increased their throwing velocity and arm swing velocity (p < 0.05) after 10 weeks of pitching training with the 4.4-oz baseball, whereas group R did not (p > 0.05). Furthermore, the percentage change in the throwing velocity and arm swing velocity of group L was significantly superior to that of group R (p < 0.05). Thus, we concluded that the 10 weeks of pitching training with an appropriate lightweight baseball substantially enhanced the arm swing velocity and throwing velocity of the adolescent baseball players. These findings suggest that using a lightweight baseball, which can reduce the risk of injury without altering pitching patterns, has positive training effects on players in the rapid physical growth and technique development stage.
Kaplan, Kevin M.; ElAttrache, Neal S.; Jobe, Frank W.; Morrey, Bernard F.; Kaufman, Kenton R.; Hurd, Wendy J.
Background There is an assumption that baseball athletes who reside in warm-weather climates experience larger magnitude adaptations in throwing shoulder motion and strength compared with their peers who reside in cold-weather climates. Hypotheses (1) The warm-weather climate (WWC) group would exhibit more pronounced shoulder motion and strength adaptations than the cold-weather climate (CWC) group, and (2) the WWC group would participate in pitching activities for a greater proportion of the year than the CWC group, with the time spent pitching predicting throwing shoulder motion and strength in both groups. Study Design Cross-sectional study; Level of evidence, 3. Methods One hundred uninjured high school pitchers (50 each WWC, CWC) were recruited. Rotational shoulder motion and isometric strength were measured and participants reported the number of months per year they pitched. To identify differences between groups, t tests were performed; linear regression was used to determine the influence of pitching volume on shoulder motion and strength. Results The WWC group pitched more months per year than athletes from the CWC group, with the number of months spent pitching negatively related to internal rotation motion and external rotation strength. The WWC group exhibited greater shoulder range of motion in all planes compared with the CWC group, as well as significantly lower external rotation strength and external/internal rotation strength ratios. There was no difference in internal rotation strength between groups, nor a difference in the magnitude of side-to-side differences for strength or motion measures. Conclusion Athletes who reside in cold- and warm-weather climates exhibit differences in throwing shoulder motion and strength, related in part to the number of months spent participating in pitching activities. The amount of time spent participating in pitching activities and the magnitude of range of motion and strength adaptations in athletes who reside
Iwame, Toshiyuki; Matsuura, Tetsuya; Suzue, Naoto; Sairyo, Koichi
playing baseball, playing period of baseball, number of training hours per week, and history of elbow pain. Data were analyzed by multivariate logistic regression models and presented as odds ratio (OR) and profile likelihood 95% confidence interval (CI) values. Results: The mean age that players were introduced to baseball was 6.6 ±1.1 years; the mean duration of play baseball was 2.7 ±1.1 years; and the proportion of players with elbow pain when throwing was 24.1%. There were 138 (10.8%) pitchers, 114 (8.9%) catchers, 524 (41.2%) infielders, and 499 (39.1%) outfielders. The initial ultrasonographic screening revealed an irregularity of the subchondral bone in 33 players (2.6%). Of the 33 players, all the players agreed to undergo radiography. Of them, 23 players were confirmed OCD. These results showed that cumulative incidence of OCD was 1.8%. Univariate analysis showed that OCD occurrence was significantly associated with age of 11-12 years (p<.01) and more than 3 years of experimental year (p<.01). Beginning age of playing baseball, number of training hours per week, playing position, and history of elbow pain were not significantly associated with OCD. Multivariate analysis showed that age of 11-12 years (OR, 3.96; 95% CI, 1.10-18.97) was risk factors significantly associated with OCD. Experimental year was not significantly associated with OCD occurrence. Conclusion: It is expected that 1.8% of youth baseball players have OCD each year. The age of 11 and 12, increased training hours per week are risk factors for OCD.
Spieth, William R.
Use of a surrogate pitcher in Mite League Baseball increased opportunities for participants to learn the fundamental skills of baseball, since the substitution reduces competitiveness and emphasis on the goal of winning. (MB)
Freeston, Jonathan; Adams, Roger D; Rooney, Kieron
Understanding factors that influence throwing speed and accuracy is critical to performance in baseball. Shoulder proprioception has been implicated in the injury risk of throwing athletes, but no such link has been established with performance outcomes. The purpose of this study was to describe any relationship between shoulder proprioception acuity and throwing speed or accuracy. Twenty healthy elite adolescent male baseball players (age, 19.6 ± 2.6 years), who had represented the state of New South Wales in the past 18 months, were assessed for bilateral active shoulder proprioception (shoulder rotation in 90° of arm abduction moving toward external rotation using the active movement extent discrimination apparatus), maximal throwing speed (MTS, meters per second measured via a radar gun), and accuracy (total error in centimeters determined by video analysis) at 80 and 100% of MTS. Although proprioception in the dominant and nondominant arms was significantly correlated with each other (r = 0.54, p < 0.01), no relationship was found between shoulder proprioception and performance. Shoulder proprioception was not a significant determinant of throwing performance such that high levels of speed and accuracy were achieved without a high degree of proprioception. There is no evidence to suggest therefore that this particular method of shoulder proprioception measurement should be implemented in clinical practice. Consequently, clinicians are encouraged to consider proprioception throughout the entire kinetic chain rather than the shoulder joint in isolation as a determining factor of performance in throwing athletes.
Objective: To present a case of chronic elbow pain as a result of a hidden underlying osteochondral defect. Clinical Features: A 17-year old baseball player presented with chronic lateral elbow pain. Examination revealed swelling of the elbow with signs of possible ligament, muscle, and tendon injury. Diagnosis and Treatment: Although there was apparent soft-tissue injury, the elbow swelling created immediate suspicion of a more serious underlying condition. Examination revealed a swollen and tender elbow, with plain x-ray confirming a subchondral bone disorder (osteochondral defect) of the capitellum. Surgical repair was performed by an orthopedic surgeon using DeNovo NT Natural Tissue Grafts: the implantation of small pieces of juvenile joint cartilage into the affected area, using glue-like fibrin. Rehabilitation of the elbow began immediately following surgery. Summary: Examination and imaging indicated that elbow pain in an adolescent baseball player could be from multiple sources, however, the chronic swelling raised suspicion of a condition requiring immediate and further investigation. PMID:27713578
Cox, David J; Sosine, Jacob; Dallery, Jesse
This study applied the generalized matching equation (GME) to pitch selection in professional baseball. The GME was fitted to the relation between pitch selection and hitter outcomes for five professional baseball pitchers during the 2014 Major League Baseball season. The GME described pitch selection well. Pitch allocation varied across different game contexts such as inning, count, and number of outs in a manner consistent with the GME. Finally, within games, bias decreased for four of the five pitchers and the sensitivity parameter increased for three of the five pitchers. The results extend the generality of the GME to multialternative natural sporting contexts, and demonstrate the influence of context on behavior in natural environments.
Simons, Jeffery P.; Wilson, Jacob M.; Wilson, Gabriel J.; Theall, Stephen
We tested expert baseball pitchers for evidence of especial skills at the regulation pitching distance. Seven college pitchers threw indoors to a target placed at 60.5 feet (18.44 m) and four closer and four further distances away. Accuracy at the regulation distance was significantly better than predicted by regression on the nonregulation…
Higgins, Brendan T; Teixeira, Rafael P; Johnson, Alan R; Carrino, John A; McFarland, Edward G
A healthy 16-year-old female baseball player was referred by her pediatrician for evaluation of pain in her right, dominant shoulder. The pain had begun insidiously 4 weeks previously after several sessions of batting practice and had worsened until she could not participate in baseball, even with low doses of ibuprofen. She was not participating in any other sports or weight lifting and had had no previous incidents of shoulder pain, but she did have a history of being able to voluntarily subluxate the right shoulder since she was a child. Her voluntary shoulder subluxation and reduction did not reproduce or worsen her pain. Results from her physical examination and radiographs were normal. Magnetic resonance imaging showed edema in the subscapularis muscle consistent with acute muscle strain. She was treated with 6 weeks of rest, ice, and anti-inflammatory medication as needed. She returned to baseball and hitting during the following 6 weeks with no limitations.
Martens, Rainer; And Others
Younger children often have problems playing baseball using adult rules because pitchers lack ability to throw consistently and batters have trouble hitting erratically thrown balls. A modification of adult rules allowed the team coach to pitch to batters. More offensive and defensive activity occurred in the nontraditional games than in…
Rice, Stephen G; Congeni, Joseph A
Baseball and softball are among the most popular and safest sports in which children and adolescents participate. Nevertheless, traumatic and overuse injuries occur regularly, including occasional catastrophic injury and even death. Safety of the athlete is a constant focus of attention among those responsible for modifying rules. Understanding the stresses placed on the arm, especially while pitching, led to the institution of rules controlling the quantity of pitches thrown in youth baseball and established rest periods between pitching assignments. Similarly, field maintenance and awareness of environmental conditions as well as equipment maintenance and creative prevention strategies are critically important in minimizing the risk of injury. This statement serves as a basis for encouraging safe participation in baseball and softball. This statement has been endorsed by the Canadian Paediatric Society.
Levin, Eugene M.
Student access to programmable calculators and computer terminals, coupled with a familiarity with baseball, provides opportunities to enhance their understanding of the binomial distribution and other aspects of analysis. (MP)
This study reports the average and SD of professional baseball players' cardiorespiratory endurance, maximum oxygen consumption, oxygen consumption during anaerobic threshold, maximum oxygen consumption of anaerobic threshold %, maximum heart rate, and heart rate of anaerobic threshold. We also report the comparison between pitchers and fielders. Considering the total number of results, percentile was used and results were classified into 5 grades. One professional baseball players' organization with more than 14 years of experience participated in this study. First, we observed that the average pitchers' V[Combining Dot Above]O2max was 53.64 ml·kg·min, whereas the average fielders' was 52.30 ml·kg·min. These values were lower than other sports players. Second, in case of the V[Combining Dot Above]O2AT, pitchers showed 39.35 ml·kg·min and fielders showed 39.96 ml·kg·min. %V[Combining Dot Above]O2AT showed a significant difference of 71.13% between pitchers and fielders-pitchers, whereas fielders showed 73.89% (p < 0.01). Third, maximal heart rates were measured at 188.69 b·min (pitchers) and 187.79 b·min (fielders). These were lower than college baseball players and higher than other sports players. In conclusion, both professional baseball pitchers and fielders should be aware of the necessity of systematic cardiorespiratory endurance data analysis. Moreover, baseball teams, athletic trainers, and coaches should also be aware of the importance of cardiorespiratory endurance.
Harris, Joshua D.; Frank, Jonathan M.; Jordan, Mark A.; Bush-Joseph, Charles A.; Romeo, Anthony A.; Gupta, Anil K.; Abrams, Geoffrey D.; McCormick, Frank M.; Bach, Bernard R.
Context: The ability to return to elite pitching, performance, and clinical outcomes of shoulder surgery in elite baseball pitchers are not definitively established. Objective: To determine (1) the rate of return to sport (RTS) in elite pitchers following shoulder surgery, (2) postoperative clinical outcomes upon RTS, and (3) performance upon RTS and to compare RTS rates in different types of shoulder surgery. Data Sources: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and checklist, Medline, SciVerse Scopus, SportDiscus, and Cochrane Central Register of Controlled Trials were searched. Study Selection: Levels I-IV evidence were eligible for inclusion if performance-based (eg, RTS) and/or clinical outcome–based reporting of outcomes were reported following surgical treatment of shoulder pathology in elite pitchers (major or minor league or collegiate). Data Extraction: Subject, shoulder, and pre- and postoperative performance-based variables of interest were extracted. All shoulder surgery types were potentially inclusive (eg, open, arthroscopic, rotator cuff, labrum, biceps, acromioclavicular joint, fracture). Study methodological quality was analyzed using the Modified Coleman Methodology Score (MCMS). Results: Six studies were analyzed (287 elite male pitchers [mean age, 27 years] who underwent shoulder surgery, with 99% on the dominant, throwing shoulder). MCMS was 38 (poor). Most pitchers were professional, with a mean career length of 6.58 years and postoperative clinical follow-up of 3.62 years. In 5 of 6 studies, multiple diagnoses were addressed concomitantly at surgery. Rate of RTS was 68% at mean 12 months following surgery. Twenty-two percent of Major League Baseball (MLB) pitchers never RTS in MLB. Overall performance did improve following surgery; however, this did not improve to pre-injury levels. Conclusion: In this systematic review, the rate of return to elite baseball pitching following surgery was
Takeuchi, Takayuki; Inomata, Kimihiro
The goal was to examine the differences in visual search strategies between expert and nonexpert baseball batters during the preparatory phase of a pitcher's pitching and accuracy and timing of swing judgments during the ball's trajectory. 14 members of a college team (Expert group), and graduate and college students (Nonexpert group), were asked to observe 10 pitches thrown by a pitcher and respond by pushing a button attached to a bat when they thought the bat should be swung to meet the ball (swing judgment). Their eye movements, accuracy, and the timing of the swing judgment were measured. The Expert group shifted their point of observation from the proximal part of the body such as the head, chest, or trunk of the pitcher to the pitching arm and the release point before the pitcher released a ball, while the gaze point of the Nonexpert group visually focused on the head and the face. The accuracy in swing judgments of the Expert group was significantly higher, and the timing of their swing judgments was significantly earlier. Expert baseball batters used visual search strategies to gaze at specific cues (the pitching arm of the pitcher) and were more accurate and relatively quicker at decision making than Nonexpert batters.
Cheshin, Arik; Heerdink, Marc W.; Kossakowski, Jolanda J.; Van Kleef, Gerben A.
Sports games are inherently emotional situations, but surprisingly little is known about the social consequences of these emotions. We examined the interpersonal effects of emotional expressions in professional baseball. Specifically, we investigated whether pitchers’ facial displays influence how pitches are assessed and responded to. Using footage from the Major League Baseball World Series finals, we isolated incidents where the pitcher’s face was visible before a pitch. A pre-study indicated that participants consistently perceived anger, happiness, and worry in pitchers’ facial displays. An independent sample then predicted pitch characteristics and batter responses based on the same perceived emotional displays. Participants expected pitchers perceived as happy to throw more accurate balls, pitchers perceived as angry to throw faster and more difficult balls, and pitchers perceived as worried to throw slower and less accurate balls. Batters were expected to approach (swing) when faced with a pitcher perceived as happy and to avoid (no swing) when faced with a pitcher perceived as worried. Whereas previous research focused on using emotional expressions as information regarding past and current situations, our work suggests that people also use perceived emotional expressions to predict future behavior. Our results attest to the impact perceived emotional expressions can have on professional sports. PMID:26909062
Fleisig, Glenn S; Laughlin, Walter A; Aune, Kyle T; Cain, E Lyle; Dugas, Jeffrey R; Andrews, James R
Controversy continues whether curveballs are stressful for young baseball pitchers. Furthermore, it is unproven whether professional baseball pitchers have fewer kinematic differences between fastballs and off-speed pitches than lower level pitchers. Kinematic and kinetic data were measured for 111 healthy baseball pitchers (26 youth, 21 high school, 20 collegiate, 26 minor league, and 18 major league level) throwing fastballs, curveballs, and change-ups in an indoor biomechanics laboratory with a high-speed, automated digitising system. Differences between pitch types and between competition levels were analysed with repeated measures ANOVA. Shoulder and elbow kinetics were greater in fastballs than in change-ups, while curveball kinetics were not different from the other two types of pitches. Kinematic angles at the instant of ball release varied between pitch types, while kinematic angles at the instant of lead foot contact varied between competition levels. There were no significant interactions between pitch type and competition level, meaning that kinetic and kinematic differences between pitch types did not vary by competition level. Like previous investigations, this study did not support the theory that curveballs are relatively more stressful for young pitchers. Although pitchers desire consistent kinematics, there were differences between pitch types, independent of competition level.
Larrick, Richard P; Timmerman, Thomas A; Carton, Andrew M; Abrevaya, Jason
In this study, we analyzed data from 57,293 Major League Baseball games to test whether high temperatures interact with provocation to increase the likelihood that batters will be hit by a pitch. Controlling for a number of other variables, we conducted analyses showing that the probability of a pitcher hitting a batter increases sharply at high temperatures when more of the pitcher's teammates have been hit by the opposing team earlier in the game. We suggest that high temperatures increase retaliation by increasing hostile attributions when teammates are hit by a pitch and by lowering inhibitions against retaliation.
Werner, S L; Fleisig, G S; Dillman, C J; Andrews, J R
By understanding pitching biomechanics, therapists can develop better preventive and rehabilitative programs for pitchers. The purpose of this study was to quantify and explain the joint motions, loads, and muscle activity that occur at the elbow during baseball pitching. Seven healthy, adult pitchers were examined with synchronized high-speed video digitization and surface electromyography. Elbow extension before ball release corresponded with a decrease in biceps activity and an increase in triceps activity. A varus torque of 120 Nm, acting to resist valgus stress, occurred near the time of maximum shoulder external rotation. Previous cadaveric research showed that the ulnar collateral ligament by itself cannot withstand a valgus load of this magnitude. Triceps, wrist flexorpronator, and anconeus activity during peak valgus stress suggests that these muscles may act as dynamic stabilizers to assist the ulnar collateral ligament in preventing valgus extension overload.
Miyazaki, Alberto Naoki; Fregoneze, Marcelo; Santos, Pedro Doneux; da Silva, Luciana Andrade; do Val Sella, Guilherme; Junior, Adriano Fernando Mendes; Soares, André Lopes; Aihara, Leandro Jun; Checchia, Sérgio Luiz
Objective: To assess the relationship between shoulder mobility and strength and the presence of pain among baseball players. Methods: Between April and July 2009, 55 baseball players were assessed by the Shoulder and Elbow Group of the School of Medical Sciences, Santa Casa de Misericórdia, São Paulo. They were all males, aged between 15 and 33 years (mean of 21); they attended an average of three training sessions per week and had been doing this sport for a mean of 10 years. Results: 14 of the 55 players evaluated were pitchers, and 20 reported pain during the pitching motion. The mean values for lateral and medial rotation and range of motion (ROM) in the dominant shoulder were, respectively, 110 °, 61 ° and 171 °, with a statistically significant difference in relation to the non-dominant limb. Pitchers had greater gains in lateral rotation and deficits in medial rotation than did non-pitchers. Pain presented a statistically significant correlation with diminished ROM, greater length of time playing the sport and situations of “shoulder at risk”. Conclusions: Statistically significant differences in dominant shoulder mobility were found, with increased lateral rotation, diminished medial rotation and smaller ROM, in relation to the contralateral limb. There was a statistically significant relationship between the pitcher's position and greater gain in lateral rotation and diminished medial rotation. There were statistically significant correlations between pain and diminished ROM, greater length of time playing the sport and situations of “shoulder at risk”. There was a statistical tendency suggesting that players with diminished medial rotation of the dominant shoulder presented a relationship with pain. PMID:27028320
Li, Xinning; Zhou, Hanbing; Williams, Phillip; Steele, John J.; Nguyen, Joseph; Jäger, Marcus; Coleman, Struan
The aim of this descriptive epidemiology study was to evaluate the injury incidence, pattern and type as a function of position in one professional baseball organization for one complete season. The study was carried out in a major academic center. Participants were all major/minor league baseball players playing for one professional organization. The disabled/injury list of one single professional baseball organization (major and minor league players) was reviewed for all of the injuries and the number of total days missed secondary to each injury. All injuries were categorized into major anatomic zones that included: shoulder, elbow, wrist/hand, back, abdomen/groin, hip, knee, and ankle/foot. The data was further stratified based on the injury type and the number of days missed due to that particular injury and a statistical analysis was performed. In pitchers, elbow injuries (n=12) resulted in 466 days missed. In catchers, wrist injuries (n=4) resulted in 89 days missed. In position players, abdominal/groin injuries (n=16) resulted in 318 days missed and shoulder injuries (n=9) resulted in 527 days missed. Overall, 134 players were injured and a total of 3209 days were missed. Pitchers had 27 times and 34 times the rate of days missed due to elbow injuries compared to position players and all players, respectively. Abdominal and groin injuries caused the pitchers to have 5.6 times and 6.4 times the rate of days missed than the position and all players, respectively. Both elbow and abdominal/groin injuries are the most disabling injury pattern seen in pitchers. Among the position players, shoulder injuries resulted in the most days missed and knee injuries resulted in the highest rate of days missed in both pitchers and catchers. PMID:23705061
Stone, Austin V.; Mannava, Sandeep; Patel, Anita; Marquez-Lara, Alejandro; Freehill, Michael T.
Background: Despite widespread use of long-toss throwing in baseball as a component of arm conditioning, interval throwing programs, and rehabilitation, long-toss distance and throwing mechanics remain controversial. Purpose: To ascertain the perceived definition of long-toss throwing through a survey of professional pitchers, pitching coaches (PCs), and certified athletic trainers (ATCs) associated with Major League Baseball. Study Design: Descriptive epidemiology study. Methods: Pitchers, PCs, and ATCs associated with 5 Major League Baseball organizations completed an anonymous survey that collected demographic data, personal use of long-toss throwing, and their perception of the distance and throwing mechanics that comprised long-toss. Results: A total of 321 surveys were completed by 271 pitchers, 19 PCs, and 31 ATCs. For all respondents, the mean distance considered as long-toss was 175 ft (95% CI, 170-181 ft). Respondents categorized the throwing mechanics of long-toss, with 36% reporting throwing “on a line” and 70% reporting long-toss as “not on a line.” Of those throwing “on a line,” 28% reported using crow-hop footwork while 60% used crow-hop footwork when throwing “not on a line.” Interpretation of long-toss distance significantly varied by position: pitchers, 177 ft (95% CI, 171-183 ft); PCs, 177 ft (95% CI, 155-200 ft); and ATCs, 157 ft (95% CI, 144-169 ft) (P = .048). When asked when long-toss throwing is used, pitchers reported using it more frequently in preseason (P = .007), during the season (P = .015), and in the off-season (P = .002) compared with that by ATCs. Functional goals for long-toss throwing demonstrated that pitchers and PCs use long-toss for shoulder stretching more frequently than ATCs (P < .001 and P = .026, respectively). ATCs used long-toss more than pitchers for interval throwing programs (P < .001). Conclusion: The definition varies for long-toss throwing distance and throwing mechanics. Pitchers and PCs believe
Fleisig, Glenn; Chu, Yungchien; Weber, Adam; Andrews, James
The aim of this study was to compare within-individual variability in baseball pitching among various levels of competition. It was hypothesized that variability decreases as level of competition increases. Five fastballs were analysed for 93 healthy male baseball pitchers (20 youth, 19 high school, 20 college, 20 Minor League, and 14 Major League level pitchers). Eleven kinematic, four temporal, and six kinetic parameters were quantified with a 240-Hz automated digitizing system. Three multiple analyses of variance were used to compare individual standard deviations for kinematic, temporal, and kinetic parameters among the five competition levels. There was a significant overall difference in kinematics and in six of the eleven kinematic parameters analysed: foot placement, knee flexion, pelvis angular velocity, elbow flexion, shoulder external rotation, and trunk forward tilt. Individual standard deviations tended to be greatest for youth pitchers, and decreased for higher levels of competition. Thus pitchers who advanced to higher levels exhibited less variability in their motions. Differences in temporal variation were non-significant; thus variability in pitching coordination was not improved at higher levels. Differences in kinetic variation were non-significant, implying no particular skill level has increased risk of injury due to variation in joint kinetics.
Hamilton, C D; Glousman, R E; Jobe, F W; Brault, J; Pink, M; Perry, J
The medical collateral ligament is a common site of injury in baseball pitchers, causing substantial morbidity and loss of pitching time. Twenty-six skilled baseball pitchers with medial collateral ligament insufficiency were studied before surgery with high-speed cinematography and fine-wire electromyography of eight muscles around the elbow. Data from the pitchers with injured elbows were compared with data obtained from uninjured pitchers. The flexor carpi radialis muscle in the pitchers with medial collateral ligament deficiencies revealed significantly decreased firing during the acceleration and deceleration phase of the fastball when compared with that of the pitchers with normal elbows, and the flexor carpi radialis muscle was significantly depressed during the early cocking and deceleration phases. The extensor muscles revealed slightly increased activity in the injured elbows; however, this was not statistically significant. Although the muscles of the flexor pronator group (especially the flexor carpi ulnaris muscle and the flexor digitorum superficialis muscles) are anatomically positioned to provide dynamic stability of the elbow, they did not demonstrate increased electrical activity in pitchers with medial collateral ligament deficiencies. This finding suggests that the muscles on the medial side of the elbow do not supplant the role of the medial collateral ligament during the fastball pitch.
Erickson, Brandon J; Bach Jr, Bernard R; Bush-Joseph, Charles A; Verma, Nikhil N; Romeo, Anthony A
The ulnar collateral ligament (UCL) is a vital structure to the overhead athlete, especially the baseball pitcher. For reasons not completely understood, UCL injuries have become increasingly more common in major league baseball (MLB) pitchers over the past 10 years. UCL reconstruction (UCLR) is the current gold standard of treatment for these injuries in MLB pitchers who wish to return to sport (RTS) at a high level and who have failed a course of non-operative treatment. Results following UCLR in MLB pitchers have been encouraging, with multiple RTS rates now cited at greater than 80%. Unfortunately, with the rising number of UCLR, there has also been a spike in the number of revision UCLR in MLB pitchers. Similar to primary UCLR, the etiology of the increase in revision UCLR, aside from an increase in the number of pitchers who have undergone a primary UCLR, remains elusive. The current literature has attempted to address several questions including those surrounding surgical technique (method of exposure, graft choice, management of the ulnar nerve, concomitant elbow arthroscopy, etc.), post-operative rehabilitation strategies, and timing of RTS following UCLR. While some questions have been answered, many remain unknown. The literature surrounding UCLR in MLB pitchers will be reviewed, and future directions regarding this injury in these high level athletes will be discussed. PMID:27335810
Müller, Sean; Fadde, Peter J; Harbaugh, Allen G
By manipulating stimulus variation in terms of opponent pitcher actions, this study investigated the capability of expert (n = 30) and near-expert (n = 95) professional baseball batters to adapt anticipation skill when using the video simulation temporal occlusion paradigm. Participants watched in-game footage of two pitchers, one after the other, that was temporally occluded at ball release and various points during ball flight. They were required to make a written prediction of pitch types and locations. Per cent accuracy was calculated for pitch type, for pitch location, and for type and location combined. Results indicated that experts and near-experts could adapt their anticipation to predict above guessing level across both pitchers, but adaptation to the left-handed pitcher was poorer than the right-handed pitcher. Small-to-moderate effect sizes were found in terms of superior adaptation by experts over near-experts at the ball release and early ball flight occlusion conditions. The findings of this study extend theoretical and applied knowledge of expertise in striking sports. Practical application of the instruments and findings are discussed in terms of applied researchers, practitioners and high-performance staff in professional sporting organisations.
Millslagle, Duane G; Hines, Bridget B; Smith, Melissa S
The quiet eye gaze behavior of 4 near-expert and 4 expert baseball umpires who called balls and strikes in simulated pitch-hit situations was assessed with a mobile eye cornea tracker system. Statistical analyses of the umpires' gaze behavior (fixation/pursuit tracking, saccades, and blinks)--onset, duration, offset, and frequency--were performed between and within 4 stages (pitcher's preparation, pitcher's delivery, ball in flight, and umpire call) by umpire's skill level. The results indicated that the quiet eye of expert umpires at onset of the pitcher's release point occurred earlier and was longer in duration than near-expert umpires. Expert expert umpires. The area outside the pitcher's ball release point may be the key environment cue for the behind-the-plate umpire.
Sakai, Shinobu; Oda, Juhachi; Yonemura, Shigeru; Sakamoto, Jiro
In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at speeds upwards of 41.7m/s (150km/hr). If a ball at this speed hits the batter, serious injury can occur. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/ LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fastball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of the injury which can be applied in actual baseball games are also discussed.
Keller, Robert A; Marshall, Nathan E; Mehran, Nima; Moutzouros, Vasilios
Glenohumeral internal rotational deficit and increased glenohumeral external rotation are common findings in baseball pitchers. To the authors' knowledge, no study has focused on the adaptation of glenohumeral internal rotational deficit and increased glenohumeral external rotation in relation to pitching speed. This study evaluated changes in range of motion in the throwing shoulder in high school pitchers to determine whether changes in internal and external rotation directly correlate with pitch velocity. The shoulders of 22 high school varsity pitchers were evaluated. Standard goniometric technique was used to measure passive external and internal glenohumeral range of motion in both arms. Measurements were evaluated for statistically significant differences in range of motion. Demographic features, including height, weight, and age, were assessed. Fifteen consecutive in-game pitch speeds were recorded, and the fastest pitch was used for evaluation. Pitch speeds were correlated to the player's glenohumeral internal rotational deficit, increased glenohumeral external rotation, and physical demographics. Average age was 16.9 years. Average external rotation of the throwing arm was significantly greater than that of the nonthrowing arm (143.00° vs 130.32°, P=.005). Average internal rotation of the throwing arm was significantly less than that of the nonthrowing arm (49.50° vs 65.90°, P=.006). Both shoulders had similar total arc of motion (throwing shoulder, 192.54; nonthrowing shoulder, 196.23; P=.822). Average maximum velocity was 77.7 mph (maximum, 88 mph; minimum, 66 mph). Maximum pitch velocity did not correlate with changes in glenohumeral internal rotational deficit (P=.683) or increased glenohumeral external rotation (P=.241). There was also no evidence of correlation between pitch velocity and player age, height, weight, or dominant hand. The stress of pitching creates adaptations to the throwing shoulder, even in young athletes. There appears to be
Ranganathan, Rajiv; Carlton, Les G
The authors examined 10 expert and 10 novice baseball batters' ability to distinguish between a fastball and a change-up in a virtual environment. They used 2 different response modes: (a) an uncoupled response in which the batters verbally predicted the type of pitch and (b) a coupled response in which the batters swung a baseball bat to try and hit the virtual ball. The authors manipulated visual information from the pitcher and ball in 6 visual conditions. The batters were more accurate in predicting the type of pitch when the response was uncoupled. In coupled responses, experts were better able to use the first 100 ms of ball flight independently of the pitcher's kinematics. In addition, the skilled batters' stepping patterns were related to the pitcher's kinematics, whereas their swing time was related to ball speed. Those findings suggest that specific task requirements determine whether a highly coupled perception-action environment improves anticipatory performance. The authors also highlight the need for research on interceptive actions to be conducted in the performer's natural environment.
Fleisig, G S; Barrentine, S W; Zheng, N; Escamilla, R F; Andrews, J R
Proper biomechanics help baseball pitchers minimize their risk of injury and maximize performance. However previous studies involved adult pitchers only. In this study, 23 youth, 33 high school, 115 college, and 60 professional baseball pitchers were analyzed. Sixteen kinematic (11 position and five velocity), eight kinetic, and six temporal parameters were calculated and compared among the four levels of competition. Only one of the 11 kinematic position parameters showed significant differences among the four levels, while all five velocity parameters showed significant differences. All eight kinetic parameters increased significantly with competition level. None of the six temporal parameters showed significant differences. Since 16 of the 17 position and temporal parameters showed no significant differences, this study supports the philosophy that a child should be taught 'proper' pitching mechanics for use throughout a career. Kinetic differences observed suggest greater injury risk at higher competition levels. Since adult pitchers did not demonstrate different position or temporal patterns than younger pitchers, increases in joint forces and torques were most likely due to increased strength and muscle mass in the higher level athlete. The greater shoulder and elbow angular velocities produced by high-level pitchers were most likely due to the greater torques they generated during the arm cocking and acceleration phases. The combination of more arm angular velocity and a longer arm resulted in greater linear ball velocity for the higher level pitcher. Thus, it appears that the natural progression for successful pitching is to learn proper mechanics as early as possible, and build strength as the body matures.
Prodromo, John; Patel, Nimit; Kumar, Neil; Denehy, Kevin; Tabb, Loni Philip; Tom, James
Background: Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, but little is known about the preoperative pitch type and velocity characteristics of pitchers who go on to undergo UCLR. Hypothesis: Pitchers who required UCLR have thrown a greater percentage of fastballs and have greater pitch velocities compared with age-matched controls in the season before injury. Study Design: Case-control study; Level of evidence, 3. Methods: MLB pitchers active during the 2002 to 2015 seasons were included. The UCLR group consisted of MLB pitchers who received UCLR between 2003 and 2015, utilizing the season before surgery (2002-2014) for analysis. The control group comprised age-matched controls of the same season. Players who pitched less than 20 innings in the season before surgery were excluded. Pitch types were recorded as percentage of total pitches thrown. Pitch velocities were recorded for each pitch type. Pitch type and pitch velocities during preoperative seasons for UCLR pitchers were compared with age-matched controls using univariate and multivariate models. Results: A total of 114 cases that went on to UCLR and 3780 controls were included in the study. Pitchers who went on to UCLR appear to have greater fastball, slider, curveball, changeup, and split-fingered fastball velocities; there were no significant differences in pitch selection between the 2 groups. Conclusion: In the season before surgery, MLB pitchers who underwent UCLR demonstrated greater fastball, slider, curveball, changeup, and split-fingered fastball velocities, with no significant difference in pitch type. PMID:27350954
Saavedra, Serguei; Powers, Scott; McCotter, Trent; Porter, Mason A.; Mucha, Peter J.
We formulate the head-to-head matchups between Major League Baseball pitchers and batters from 1954 to 2008 as a bipartite network of mutually-antagonistic interactions. We consider both the full network and single-season networks, which exhibit structural changes over time. We find interesting structure in the networks and examine their sensitivity to baseball’s rule changes. We then study a biased random walk on the matchup networks as a simple and transparent way to (1) compare the performance of players who competed under different conditions and (2) include information about which particular players a given player has faced. We find that a player’s position in the network does not correlate with his placement in the random walker ranking. However, network position does have a substantial effect on the robustness of ranking placement to changes in head-to-head matchups.
Bahill, A Terry; Baldwin, David G
The right-hand rules show the direction of the spin-induced deflection of baseball pitches: thus, they explain the movement of the fastball, curveball, slider and screwball. The direction of deflection is described by a pair of right-hand rules commonly used in science and engineering. Our new model for the magnitude of the lateral spin-induced deflection of the ball considers the orientation of the axis of rotation of the ball relative to the direction in which the ball is moving. This paper also describes how models based on somatic metaphors might provide variability in a pitcher's repertoire.
Krieger, Joseph R; Kourtev, Peter S
Carnivorous plants of the genus Sarracenia rely on microorganisms in their pitchers to decompose drowned insects. The environment inside pitchers is considered to be aerobic; however, there might be zones, such as at the bottom of the pitcher, where anaerobic conditions develop. Samples of the sediment at the bottom of Sarracenia purpurea pitchers were analyzed for the presence of archaea, using PCR and sequencing of the 16S rRNA gene. Archaeal DNA was detected in 20% of sampled pitchers. All sequences were closely related to Methanobrevibacter . Therefore, pitchers may contain anoxic zones inhabited by methanogens.
Bradbury, John Charles
Baseball players exhibit a pattern of improvement and decline in performance; however, differing lengths of careers and changes in rules and characteristics of the game complicate assessments of age-related effects on performance. This study attempts to isolate the impact of age on several player skills while controlling for relevant outside factors using longitudinal data from 86 seasons of Major League Baseball. The results indicate that players age in different skills in accord with studies of ageing in other athletic contests. For overall performance, multiple-regression estimates indicate that hitters and pitchers peak around the age of 29 - later than previous estimates. Athletic skills such as hitting and running peak earlier than skills that rely heavily on experience and knowledge, such as issuing and drawing walks.
McGinnis, Ryan S.; Perkins, Noel C.
Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher's hand. While radar guns and video-based motion capture (mocap) resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU) that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball's velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.
Axe, Michael; Hurd, Wendy; Snyder-Mackler, Lynn
Context: Baseball throwing injuries are common. Emphasis on injury prevention and rehabilitation is made in an attempt to keep athletes on the field of competition. Interval throwing programs are an integral part of training, conditioning, and returning an injured baseball player to the game. Evidence Acquisition: Development of data-driven programs was based on the number, type, distance, and intensity of throws during games, across the spectrum of ages and positions for baseball athletes at all levels of play. Statistical analysis by age, position, and level of play determined the need for separate throwing programs. Means, the high range, game rules, and practical considerations were used to develop each data-based interval throwing program. Results: Data-based age and level-of-play interval throwing programs for pitchers, catchers, infielders, and outfielders have been developed, tested, and implemented for more than 10 years. Progression is based on type and location of injury, symptoms in response to throwing, and preinjury performance profile. Although the throwing programs are highly structured, there is ample opportunity to modify them to meet the needs of individual athletes. Conclusion: Data-based interval throwing programs for baseball athletes are an integral training and conditioning element for both injured and uninjured athletes who are preparing for sports participation. Medical team members should equip themselves with an understanding of how to use the programs for safe training, conditioning, and return to play. PMID:23015866
Escamilla, Rafael F; Ionno, Michele; deMahy, M Scott; Fleisig, Glenn S; Wilk, Kevin E; Yamashiro, Kyle; Mikla, Tony; Paulos, Lonnie; Andrews, James R
Throwing velocity is an important baseball performance variable for baseball pitchers, because greater throwing velocity results in less time for hitters to make a decision to swing. Throwing velocity is also an important baseball performance variable for position players, because greater throwing velocity results in decreased time for a runner to advance to the next base. This study compared the effects of 3 baseball-specific 6-week training programs on maximum throwing velocity. Sixty-eight high school baseball players 14-17 years of age were randomly and equally divided into 3 training groups and a nontraining control group. The 3 training groups were the Throwers Ten (TT), Keiser Pneumatic (KP), and Plyometric (PLY). Each training group trained 3 d·wk(-1) for 6 weeks, which comprised approximately 5-10 minutes for warm-up, 45 minutes of resistance training, and 5-10 for cool-down. Throwing velocity was assessed before (pretest) and just after (posttest) the 6-week training program for all the subjects. A 2-factor repeated measures analysis of variance with post hoc paired t-tests was used to assess throwing velocity differences (p < 0.05). Compared with pretest throwing velocity values, posttest throwing velocity values were significantly greater in the TT group (1.7% increase), the KP group (1.2% increase), and the PLY group (2.0% increase) but not significantly different in the control group. These results demonstrate that all 3 training programs were effective in increasing throwing velocity in high school baseball players, but the results of this study did not demonstrate that 1 resistance training program was more effective than another resistance training program in increasing throwing velocity.
Woodfin, Samantha, Ed.
This is the third issue of the magazine to focus on baseball in Panola County (Texas). The issue salutes the Carthage High School baseball program during two periods of its history. The first period was the early 1940's under Coach E. B. Morrison, whose teams were State Finalists in 1941 and 1942. The second period covered is the era of Coach…
GRABER, RALPH S.
BASEBALL FICTION HAS MOVED FROM THE JUVENILE STORIES OF THE TURN OF THE CENTURY TO ADULT FICTION IN WHICH THE GAME IS EXAMINED FOR THE LIGHT IT SHEDS ON THE PARADOXES OF AMERICAN LIFE. EARLY BASEBALL FICTION WAS DIRECTED TOWARD THE DIME-NOVEL AUDIENCE, BUT AFTER WORLD WAR I, SUCH WRITERS AS HEYWOOD BROUN AND RING LARDNER AIMED FOR ADULT READERS…
Whiteside, David; Martini, Douglas N; Zernicke, Ronald F; Goulet, Grant C
Whiteside, D, Martini, DN, Zernicke, RF, and Goulet, GC. Ball speed and release consistency predict pitching success in Major League Baseball. J Strength Cond Res XX(X): 000-000, 2015-This study aimed to quantify how ball flight kinematics (i.e., ball speed and movement), release location, and variations therein relate to pitching success in Major League Baseball (MLB). One hundred ninety starting MLB pitchers met the inclusion criteria for this study. Ball trajectory information was collected for 76,000 pitches and inserted into a forward stepwise multiple regression model, which examined how (a) pitch selection, (b) ball speed, (c) ball movement (horizontal and lateral), (d) release location (horizontal and lateral), (e) variation in pitch speed, (f) variation in ball movement, and (g) variation in release location related to pitching success (as measured by fielding independent pitching-FIP). Pitch speed, release location variability, variation in pitch speed, and horizontal release location were significant predictors of FIP and, collectively, accounted for 24% of the variance in FIP. These findings suggest that (a) maximizing ball speed, (b) refining a consistent spatial release location, and (c) using varied pitch speeds should be primary foci for the pitching coach. However, between-pitcher variations underline how training interventions should be administered at the individual level, with consideration given to the pitcher's injury history. Finally, despite offering significant predictors of success, these three factors explained only 22% of the variance in FIP and should not be considered the only, or preeminent, indicators of a pitcher's effectiveness. Evidently, traditional pitching metrics only partly account for a pitcher's effectiveness, and future research is necessary to uncover the remaining contributors to success.
NASA is known for rocket science and airplanes, but for baseball? NASA researchers like to solve down-to-Earth problems like how far will a batted ball travel or what makes a curve ball curve? Aero...
George Eli Bennett was born in Claryville, NY, in the Catskill Mountains, in 1885 . His parents both died by the time he was 11, leaving him the need to work while going to school, but he excelled in school and sports. He played semipro baseball at the age of 16. After high school he work in various jobs in the Midwest before he could afford to attend the University of Maryland Medical School, from which he graduated in 1908. At the age of 25 in 1910, he joined the staff at the Johns Hopkins Hospital, where he remained until his resignation in 1947. Dr. Bennett was one of a few men who served as President of both the American Orthopaedic Association and the American Academy of Orthopaedic Surgeons. While Dr. Bennett made many contributions to orthopaedic surgery, including children’s and nonoperative orthopaedics, he was best known for his work in sports medicine (undoubtedly related to his being a gifted athlete). His fame extended well beyond the orthopaedic community, for he treated many famous athletes. Sports Illustrated recognized him upon his death in an article entitled, “Mender of Immortals” . His intimate knowledge of sports undoubtedly contributed to his sage judgments. At an emotional dinner in 1958 many famous athletes sometimes tearfully paid tribute to Dr. Bennett. Joe Garagiola commented on the occasion, “After listening to that all-star team of players Dr. Bennett has mended, I’m sorry I didn’t break my leg” . Among Dr. Bennett’s many publications, including those related to sports, we have chosen one  of two articles [1,2] he wrote on elbow and shoulder problems in baseball players. He described the now well-known degenerative changes and periarticular calcific deposits that occur in the elbows and shoulders of pitchers. Some of these, he suggested, were not symptomatic and he advised against treatment. Dr. Bennett commented, however, “Since professional athletes are human beings, not supermen, general health often
Sonne, Michael W L; Keir, Peter J
Major League Baseball (MLB) has proposed rule changes to speed up baseball games. Reducing the time between pitches may impair recovery from fatigue. Fatigue is a known precursor to injury and may jeopardise joint stability. This study examined how fatigue accumulated during baseball games and how different pace of play initiatives may influence fatigue. Pitcher data were retrieved from a public database. A predictive model of muscle fatigue estimated muscle fatigue in 8 arm muscles. A self-selected pace (22.7 s), 12 s pace (Rule 8.04 from the MLB) and a 20 s rest (a pitch clock examined in the 2014 Arizona Fall League (AFL)) were examined. Significantly more muscle fatigue existed in both the AFL and Rule 8.04 conditions, when compared to the self-selected pace condition (5.01 ± 1.73%, 3.95 ± 1.20% and 3.70 ± 1.10% MVC force lost, respectively). Elevated levels of muscle fatigue are predicted in the flexor-pronator mass, which is responsible for providing elbow stability. Reduced effectiveness of the flexor-pronator mass may reduce the active contributions to joint rotational stiffness, increasing strain on the ulnar collateral ligament (UCL) and possibly increasing injury risk.
Jinji, Tsutomu; Sakurai, Shinji
In this study, we aimed to determine the direction of the spin axis and the spin rate of pitched baseballs and to estimate the associated aerodynamic forces. In addition, the effects of the spin axis direction and spin rate on the trajectory of a pitched baseball were evaluated. The trajectories of baseballs pitched by both a pitcher and a pitching machine were recorded using four synchronized video cameras (60 Hz) and were analyzed using direct linear transform (DLT) procedures. A polynomial function using the least squares method was used to derive the time-displacement relationship of the ball coordinates during flight for each pitch. The baseball was filmed immediately after ball release using a high-speed video camera (250 Hz), and the direction of the spin axis and the spin rate (omega) were calculated based on the positional changes of the marks on the ball. The lift coefficient was correlated closely with omegasinalpha (r = 0.860), where alpha is the angle between the spin axis and the pitching direction. The term omegasinalpha represents the vertical component of the velocity vector. The lift force, which is a result of the Magnus effect occurring because of the rotation of the ball, acts perpendicularly to the axis of rotation. The Magnus effect was found to be greatest when the angular and translational velocity vectors were perpendicular to each other, and the break of the pitched baseball became smaller as the angle between these vectors approached 0 degrees. Balls delivered from a pitching machine broke more than actual pitcher's balls. It is necessary to consider the differences when we use pitching machines in batting practice.
Nicholls, Rochelle; Fleisig, Glenn; Elliott, Bruce; Lyman, Stephen; Osinski, Edmund
Baseball pitching must be performed with correct technique if injuries are to be avoided and performance maximized. High-speed video analysis is accepted as the most accurate and objective method for evaluation of baseball pitching mechanics. The aim of this research was to develop an equivalent qualitative analysis method for use with standard video equipment. A qualitative analysis protocol (QAP) was developed for 24 kinematic variables identified as important to pitching performance. Twenty male baseball pitchers were videotaped using 60 Hz camcorders, and their technique evaluated using the QAP, by two independent raters. Each pitcher was also assessed using a 6-camera 200 Hz Motion Analysis system (MAS). Four QAP variables (22%) showed significant similarity with MAS results. Inter-rater reliability showed agreement on 33% of QAP variables. It was concluded that a complete and accurate profile of an athlete's pitching mechanics cannot be made using the QAP in its current form, but it is possible such simple forms of biomechanical analysis could yield accurate results before 3-D methods become obligatory.
Petersen, Alexander M.; Jung, Woo-Sung; Stanley, H. Eugene
Statistical analysis is a major aspect of baseball, from player averages to historical benchmarks and records. Much of baseball fanfare is based around players exceeding the norm, some in a single game and others over a long career. Career statistics serve as a metric for classifying players and establishing their historical legacy. However, the concept of records and benchmarks assumes that the level of competition in baseball is stationary in time. Here we show that power law probability density functions, a hallmark of many complex systems that are driven by competition, govern career longevity in baseball. We also find similar power laws in the density functions of all major performance metrics for pitchers and batters. The use of performance-enhancing drugs has a dark history, emerging as a problem for both amateur and professional sports. We find statistical evidence consistent with performance-enhancing drugs in the analysis of home runs hit by players in the last 25 years. This is corroborated by the findings of the Mitchell Report (2007), a two-year investigation into the use of illegal steroids in Major League Baseball, which recently revealed that over 5 percent of Major League Baseball players tested positive for performance-enhancing drugs in an anonymous 2003 survey.
Campbell, Brian M; Stodden, David F; Nixon, Megan K
The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.
Ryu, Kwangmin; Kim, Jingu; Ali, Asif; Kim, Woojong; Radlo, Steven J
In baseball, one factor necessary for batters to decide whether to swing or not depends on what type of pitch is thrown. Oftentimes batters will look for their pitch (i.e., waiting for a fastball). In general, when a pitcher has many types of pitches in his arsenal, batters will have greater difficulty deciding upon the pitch thrown. Little research has been investigated the psychophysiology of a batters decision-making processes. Therefore, the primary purpose of this study was to determine how brain activation changes according to an increase in the number of alternatives (NA) available. A total of 15 male college baseball players participated in this study. The stimuli used in this experiment were video clips of a right-handed pitcher throwing fastball, curve, and slider pitches. The task was to press a button after selecting the fastball as the target stimulus from two pitch choices (fastball and curve), and then from three possibilities (fastball, curve, and slider). Functional and anatomic image scanning magnetic resonance imaging (MRI) runs took 4 and 5[Formula: see text]min, respectively. According to our analysis, the right precentral gyrus, left medial frontal gyrus, and right fusiform gyrus were activated when the NA was one. The supplementary motor areas (SMA) and primary motor cortex were activated when there were two alternatives to choose from and the inferior orbitofrontal gyrus was specifically activated with three alternatives. Contrary to our expectations, the NA was not a critical factor influencing the activation of related decision making areas when the NA was compared against one another. These findings highlight that specific brain areas related to decision making were activated as the NA increased.
Wang, Y T; Ford, H T; Ford, H T; Shin, D M
To examine the relationships of pitching performance to maximum external rotation of the shoulder and to time in the acceleration phase, 3 male baseball pitchers were tested using three-dimensional cinematography. Analysis indicated that increasing maximum external rotation of the shoulder at the very beginning of the acceleration phase would help to generate a higher pitching ball velocity since a greater linear and angular displacement could be used to accelerate the throwing forearm. Slowing the wrist action just before ball-release may be a key technique to increasing pitching velocity of the ball.
MacWilliams, B A; Choi, T; Perezous, M K; Chao, E Y; McFarland, E G
Overhand throwing requires contributions from and interaction between all limb segments. Most previous investigations have concentrated on the throwing arm itself, yet poor mechanics at the arm may originate in the lower extremities. Multicomponent ground-reaction forces of both the push-off and landing limbs were measured in six collegiate and one high school level baseball pitchers. Full body kinematics were simultaneously recorded to correlate phases in the pitching cycle with the force data. Pitchers were found to generate shear forces of 0.35 body weight in the direction of the pitch with the push-off leg and to resist forces of 0.72 body weight with the landing leg. Wrist velocity was found to correlate highly with increased leg drive. This study validates the clinical impression that the lower extremity is an important contributor to the throwing motion. Based on this study, strengthening of the lower extremities could be inferred to be important both to enhance performance and to avoid injury.
Fortenbaugh, Dave; Fleisig, Glenn S.; Andrews, James R.
Context: Baseball pitching kinematics, kinetics, ball velocity, and injuries at the shoulder and elbow are related. Evidence Acquisition: PubMed and Sport Discus were searched for original studies published between 1994 and 2008. Relevant references in these studies were retrieved. Inferential studies that tested relationships between kinematics and kinetics were included, as were studies that tested relationships between kinematics and ball velocity. Descriptive studies that simply quantified kinematics and/or kinetics were excluded. Results: Several kinematic parameters at the instant of foot contact were associated with increased upper extremity kinetics: front foot position, front foot orientation, shoulder abduction, and shoulder horizontal adduction. The timing of shoulder external rotation, pelvis rotation, and upper trunk rotation was associated with increased kinetics and decreased ball velocity. Low braking force of the lead leg and a short stride were associated with decreased ball velocity. Decreased maximum shoulder external rotation, shoulder abduction, knee extension, and trunk tilt were also associated with decreased ball velocity. As pitchers develop, kinematic values remain similar, their variability reduces, and kinetic values gradually increase. Slight kinematic variations were seen among pitch types, although the kinetics of fastballs and curveballs were relatively the same; changeup kinetics were the lowest. As pitchers fatigued, kinetic values remained constant, but increases in arm pain were reported. Conclusions: Several kinematic parameters were related to joint kinetics and ball velocity. To enhance performance and reduce injury risk, pitchers need to learn proper fastball mechanics at an early age. A changeup is recommended as a safe secondary pitch to complement the fastball; the curveball can be added after fastball and changeup mechanics are mastered. Avoiding overuse and pitching while fatigued is necessary to minimize the risk of
Shitara, Hitoshi; Yamamoto, Atsushi; Shimoyama, Daisuke; Ichinose, Tsuyoshi; Sasaki, Tsuyoshi; Hamano, Noritaka; Ueno, Akira; Endo, Fumitaka; Oshima, Atsufumi; Sakane, Hideo; Tachibana, Masahiro; Tomomatsu, Yusuke; Tajika, Tsuyoshi; Kobayashi, Tsutomu; Osawa, Toshihisa; Iizuka, Haku; Takagishi, Kenji
We prospectively evaluated the effects of a prevention program on the incidence of shoulder and elbow injuries in high school baseball pitchers. Ninety-two pitchers participated in this study and were taught to perform stretching and strength exercises aimed at improving shoulder external rotation strength in the preseason. The pitchers freely chose to participate in one of four groups [SM-group: performed both exercises, S-group: performed stretching exercise only, M-group: performed strength training only, and N-group: performed neither intervention]. Injury was defined as inability to play for ≥8 days because of shoulder/elbow symptoms. Kaplan-Meier survival curves were generated and hazard ratios (HRs) for injury occurrence were calculated using multivariate Cox regression. Log-rank test was used for between-group comparisons of survival distributions. The injuries occurred in 25, 35, and 57% of participants and median times to injury were 89, 92, and 29.5 days in the S- (n = 32), SM- (n = 46), and N- (n = 14) group, respectively. Nobody chose M-group. HRs were 0.36 and 0.47 for the S- and SM-group, respectively, based on the N-group. The incidence of injury was significantly lower in the S-group than in the N-group (p = 0.04). Daily posterior shoulder stretching may reduce the incidence of the injuries in high school baseball pitchers. PMID:28345616
Baseball research generally acts as a window into the game--a means as it were to understand its underlying order and disorder, its hidden beauty and historic complexity. Less common is the view from the other side of the window in which the patterns of the game are a lens as it were into the outside world, a channel for making sense of a…
The author describes the system outline, features and operations of "Nikkan Sports Realtime Basaball Database" which was developed and operated by Nikkan Sports Shimbun, K. K. The system enables to input numerical data of professional baseball games as they proceed simultaneously, and execute data updating at realtime, just-in-time. Other than serving as supporting tool for prepareing newspapers it is also available for broadcasting media, general users through NTT dial Q2 and others.
Fleisig, Glenn S; Hsu, Wellington K; Fortenbaugh, Dave; Cordover, Andrew; Press, Joel M
The purpose of this study was to quantify trunk axial rotation and angular acceleration in pitching and batting of elite baseball players. Healthy professional baseball pitchers (n = 40) and batters (n = 40) were studied. Reflective markers attached to each athlete were tracked at 240 Hz with an eight-camera automated digitizing system. Trunk axial rotation was computed as the angle between the pelvis and the upper trunk in the transverse plane. Trunk angular acceleration was the second derivative of axial rotation. Maximum trunk axial rotation (55 +/- 6 degrees) and angular acceleration (11,600 +/- 3,100 degrees/s2) in pitching occurred before ball release, approximately at the instant the front foot landed. Maximum trunk axial rotation (46 +/- 9 degrees) and angular acceleration (7,200 +/- 2,800 degrees/s2) in batting occurred in the follow-through after ball contact. Thus, the most demanding instant for the trunk and spine was near front foot contact for pitching and after ball contact for batting.
Armitage, David W
Bacteria are hypothesized to provide a variety of beneficial functions to plants. Many carnivorous pitcher plants, for example, rely on bacteria for digestion of captured prey. This bacterial community may also be responsible for the low surface tensions commonly observed in pitcher plant digestive fluids, which might facilitate prey capture. I tested this hypothesis by comparing the physical properties of natural pitcher fluid from the pitcher plant Darlingtonia californica and cultured 'artificial' pitcher fluids and tested these fluids' prey retention capabilities. I found that cultures of pitcher leaves' bacterial communities had similar physical properties to raw pitcher fluids. These properties facilitated the retention of insects by both fluids and hint at a previously undescribed class of plant-microbe interaction.
Koban, Lori; McNelis, Erin
Fantasy baseball, a game invented in 1980, allows baseball fans to become managers of pretend baseball teams. In most fantasy baseball leagues, participants choose teams consisting of major league players who they believe will do well in five offensive categories (batting average, home runs, runs batted in, stolen bases, and runs scored) or in…
Presents a lesson plan exploring social values and historical periods as it is reflected in the sport of baseball. Suggests that teachers start with an overview of the game's history and rules in the nineteenth century. Includes four sets of quotes relating to baseball and race, capitalism, community, and cultural context. (DK)
Chou, Lee Yiung; Clarke, Charles M; Dykes, Gary A
Nepenthes pitcher plants produce modified jug-shaped leaves to attract, trap and digest insect prey. We used 16S rDNA cloning and sequencing to compare bacterial communities in pitcher fluids of each of three species, namely Nepenthes ampullaria, Nepenthes gracilis and Nepenthes mirabilis, growing in the wild. In contrast to previous greenhouse-based studies, we found that both opened and unopened pitchers harbored bacterial DNA. Pitchers of N. mirabilis had higher bacterial diversity as compared to other Nepenthes species. The composition of the bacterial communities could be different between pitcher types for N. mirabilis (ANOSIM: R = 0.340, p < 0.05). Other Nepenthes species had similar bacterial composition between pitcher types. SIMPER showed that more than 50 % of the bacterial taxa identified from the open pitchers of N. mirabilis were not found in other groups. Our study suggests that bacteria in N. mirabilis are divided into native and nonnative groups.
Yanai, Toshimasa; Matsuo, Akifumi; Maeda, Akira; Nakamoto, Hiroki; Mizutani, Mirai; Kanehisa, Hiroaki; Fukunaga, Tetsuo
We developed a force measurement system in a soil-filled mound for measuring ground reaction forces (GRFs) acting on baseball pitchers and examined the reliability and validity of kinetic and kinematic parameters determined from the GRFs. Three soil-filled trays of dimensions that satisfied the official baseball rules were fixed onto three force platforms. Eight collegiate pitchers wearing baseball shoes with metal cleats were asked to throw 5 fastballs with maximum effort from the mound toward a catcher. The reliability of each parameter was determined for each subject as the coefficient of variation across the 5 pitches. The validity of the measurements was tested by comparing the outcomes either with the true values or the corresponding values computed from a motion capture system. The coefficients of variation in the repeated measurements of the peak forces ranged from 0.00 to 0.17, and were smaller for the pivot foot than the stride foot. The mean absolute errors in the impulses determined over entire duration of pitching motion were 5.3 N·s, 1.9 N·s, and 8.2 N·s for the X-, Y-, and Z-directions, respectively. These results suggest that the present method is reliable and valid for determining selected kinetic and kinematic parameters for analyzing pitching performance.
DeFroda, Steven F.; Kriz, Peter K.; Hall, Amber M.; Zurakowski, David; Fadale, Paul D.
Background: Ulnar collateral ligament (UCL) injury has become increasingly common in Major League Baseball (MLB) players in recent years. Hypothesis: There is a significant difference in preinjury fastball velocity between MLB pitchers with tears and matched controls without UCL injury. Pitchers with injuries are throwing harder and getting injured earlier in their MLB careers. Study Design: Cohort study; Level of evidence, 3. Methods: From 2007 to 2014, a total of 170 documented UCL injuries (156 pitchers, 14 position players) occurred in MLB. Inclusion criteria for this study consisted of any player who tore his UCL in MLB during this time frame. There were 130 regular-season tears (April-September). From this group, 118 players who pitched more than 100 innings prior to tear were matched to subjects with no tear and were compared using a logistic regression analysis. A subgroup of “early tear” players who threw less than 100 career innings (n = 37) was also identified and compared with the larger tear group using a logistic regression analysis. Results: Of the 130 tears that occurred during the regular season, a significantly larger number (62%) occurred in the first 3 months (P = .011). The rate of UCL tears per MLB player (P = .001) was statistically significant. In the group of 118 matched tears, the mean fastball velocity was greater in the tear group (91.7 mph) compared with the control group (91.0 mph; P = .014). Furthermore, relief pitchers made up a greater percentage of the early tear group (<100 innings) compared with the later tear group (P = .011). Sixteen of the 170 UCL tears (9.4%) were recurrent tears, with 5 of 16 experiencing both tear and retear within the past 4 years. Conclusion: There is a statistically significant difference in the mean fastball velocity of pitchers who injure their UCL. Small increases in pitcher fastball velocity are a main contribution to the increased rate of tear in MLB. In addition, there has been an increased
Naito, Kozo; Takagi, Hiroyasu; Yamada, Norimasa; Hashimoto, Shinichi; Maruyama, Takeo
The shoulder internal rotation (IR) and forearm pronation (PR) are important elements for baseball pitching, however, how rapid rotations of IR and PR are produced by muscular torques and inter-segmental forces is not clear. The aim of this study is to clarify how IR and PR angular velocities are maximized, depending on muscular torque and interactive torque effects, and gain a detailed knowledge about inter-segmental interaction within a multi-joint linked chain. The throwing movements of eight collegiate baseball pitchers were recorded by a motion capture system, and induced-acceleration analysis was used to assess the respective contributions of the muscular (MUS) and interactive torques associated with gyroscopic moment (GYR), and Coriolis (COR) and centrifugal forces (CEN) to maximum angular velocities of IR (MIRV) and PR (MPRV). The results showed that the contribution of MUS account for 98.0% of MIRV, while that contribution to MPRV was indicated as negative (-48.1%). It was shown that MPRV depends primarily on the interactive torques associated with GYR and CEN, but the effects of GYR, COR and CEN on MIRV are negligible. In conclusion, rapid PR motion during pitching is created by passive-effect, and is likely a natural movement which arises from 3D throwing movement. Applying the current analysis to IR and PR motions is helpful in providing the implications for improving performance and considering conditioning methods for pitchers.
Wang, Lin-Hwa; Lo, Kuo-Cheng; Jou, I-Ming; Kuo, Li-Chieh; Tai, Ta-Wei; Su, Fong-Chin
This study investigated the contribution of flexor muscles to the forearm through fatigue; therefore, the differences in forearm mechanisms on the pitching motion in fastball were analysed. Fifteen baseball pitchers were included in this study. Ultrasonographical examination of participants' ulnar nerve in the cubital tunnel with the elbow extended and at 45°, 90° and 120° of flexion was carried. A three-dimensional motion analysis system with 14 reflective markers attached on participants was used for motion data collection. The electromyography system was applied over the flexor carpi ulnaris, flexor carpi radialis and extensor carpi radialis muscles of the dominant arm. Flexor carpi ulnaris muscle activity showed a significant difference during the acceleration phase, with a peak value during fastball post-fatigue (P = 0.02). Significant differences in the distance between ulnar nerve and medial condyle on throwing arm and non-throwing arm were observed as the distance increased with the elbow movement from 0° to 120° of flexion (P = 0.01). The significant increase of the flexor carpi ulnaris muscle activity might be responsible for maintaining the stability of the wrist joint. The increased diameter might compress the ulnar nerve and cause several pathological changes. Therefore, fatigue in baseball pitchers still poses a threat to the ulnar nerve because the flexor carpi ulnaris and flexor carpi radialis all originate from the medial side of the elbow, and the swelling tendons after fatigue might be a key point.
Moran, Jonathan A; Chin, Lijin
Three species of Nepenthes pitcher plants from Borneo engage in a mutualistic interaction with mountain tree shrews, the basis of which is the exchange of nutritional resources. The plants produce modified “toilet pitchers” that produce copious amounts of exudates, the latter serving as a food source for tree shrews. The exudates are only accessible to the tree shrews when they position their hindquarters over the pitcher orifice. Tree shrews mark valuable resources with feces and regularly defecate into the pitchers when they visit them to feed. Feces represent a valuable source of nitrogen for these Nepenthes species, but there are many facets of the mutualism that are yet to be investigated. These include, but are not limited to, seasonal variation in exudate production rates by the plants, behavioral ecology of visiting tree shrews and the mechanism by which the plants signal to tree shrews that their pitchers represent a food source. Further research into this extraordinary animal-plant interaction is required to gain a better understanding of the benefits to the participating species. PMID:20861680
Bishop, Stacy H; Herron, Robert L; Ryan, Gregory A; Katica, Charles P; Bishop, Phillip A
The throwing arm of a baseball pitcher is subjected to high stress as a result of the repetitive activity of pitching. Intermittent cryotherapy may facilitate recovery from this repeated high stress, but few researchers have investigated cryotherapy's efficacy in an ecologically valid setting. This study investigated the effects of intermittent cryotherapy on pitching velocity and subjective measures of recovery and exertion in a simulated baseball game. Trained college-aged male baseball pitchers (n = 8) threw 12 pitches (1 pitch every 20 seconds) per inning for 5 total innings during a simulated pitching start. Between each inning, pitchers received shoulder and arm cooling (AC) or, on a separate occasion, no cooling (NC). All sessions took place in a temperate environment (18.3 ± 2.8° C; 49 ± 4% relative humidity). Pitch speeds were averaged for each participant each inning and overall for 5 innings. Perceived exertion (rating of perceived exertion [RPE]) was recorded at the end of each simulated inning. Perceived recovery (perceived recovery scale [PRS]) was recorded after treatment between each inning. Mean pitching velocity for all-innings combined was higher (p = 0.04) for shoulder and elbow cooling (AC) (31.2 ± 2.1 m·s) than for no cooling (NC) (30.6 ± 2.1 m·s). Average pitch speed was significantly higher in the fourth (p = <0.01) and fifth (p = 0.02) innings in AC trial (31.3 ± 2 m·s for both innings) compared with NC trial (30.0 ± 2.22 m·s and 30.4 ± 1.99 m·s, for the fourth and fifth innings, respectively. AC resulted in a significantly lower RPE (p ≤ 0.01) and improved PRS (p ≤ 0.01) compared with NC. Intermittent cryotherapy attenuated velocity loss in baseball pitching, decreased RPE, and facilitated subjective recovery during a 5-inning simulated game.
Higuchi, Takatoshi; Nagami, Tomoyuki; Nakata, Hiroki; Watanabe, Masakazu; Isaka, Tadao; Kanosue, Kazuyuki
The contribution of visual information about a pitched ball to the accuracy of baseball-bat contact may vary depending on the part of trajectory seen. The purpose of the present study was to examine the relationship between hitting accuracy and the segment of the trajectory of the flying ball that can be seen by the batter. Ten college baseball field players participated in the study. The systematic error and standardized variability of ball-bat contact on the bat coordinate system and pitcher-to-catcher direction when hitting a ball launched from a pitching machine were measured with or without visual occlusion and analyzed using analysis of variance. The visual occlusion timing included occlusion from 150 milliseconds (ms) after the ball release (R+150), occlusion from 150 ms before the expected arrival of the launched ball at the home plate (A-150), and a condition with no occlusion (NO). Twelve trials in each condition were performed using two ball speeds (31.9 m·s-1 and 40.3 m·s-1). Visual occlusion did not affect the mean location of ball-bat contact in the bat’s long axis, short axis, and pitcher-to-catcher directions. Although the magnitude of standardized variability was significantly smaller in the bat’s short axis direction than in the bat’s long axis and pitcher-to-catcher directions (p < 0.001), additional visible time from the R+150 condition to the A-150 and NO conditions resulted in a further decrease in standardized variability only in the bat’s short axis direction (p < 0.05). The results suggested that there is directional specificity in the magnitude of standardized variability with different visible time. The present study also confirmed the limitation to visual information is the later part of the ball trajectory for improving hitting accuracy, which is likely due to visuo-motor delay. PMID:26848742
Krieger, Joseph R; Kourtev, Peter S
Pitcher plants have been widely used in ecological studies of food webs; however, their bacterial communities are poorly characterized. Pitchers of Sarracenia purpurea contain several distinct sub-habitats, namely the bottom sediment, the liquid, and the internal pitcher wall. We hypothesized that those three sub-habitats within pitcher plants are inhabited by distinct bacterial populations. We used denaturing gradient gel electrophoresis and 16S rRNA gene sequencing to characterize bacterial populations in pitchers from three bogs. DGGE and sequencing revealed that in any given pitcher, the three sub-habitats contain significantly different bacterial populations. However, there was significant variability between bacterial populations inhabiting the same type of habitat in different pitchers, even at the same site. Therefore, no consistent set of bacterial populations was enriched in any of the three sub-habitats. All sub-habitats appeared to be dominated by alpha- and betaproteobacteria in differing proportions. In addition, sequences from the Bacteroidetes and Firmicutes were obtained from all three sub-habitats. We conclude that container aquatic habitats such as the pitchers of S. purpurea possess a very high bacterial diversity, with many unique bacterial populations enriched in individual pitchers. Within an individual pitcher, populations of certain bacterial families may be enriched in one of the three studied sub-habitats.
Background Observing competitive games such as sports is a pervasive entertainment among humans. The inclination to watch others play may be based on our social-cognitive ability to understand the internal states of others. The mirror neuron system, which is activated when a subject observes the actions of others, as well as when they perform the same action themselves, seems to play a crucial role in this process. Our previous study showed that activity of the mirror neuron system was modulated by the outcome of the subject's favored player during observation of a simple competitive game (rock-paper-scissors). However, whether the mirror neuron system responds similarly in a more complex and naturalistic sports game has not yet been fully investigated. Methodology/Principal Findings In the present study, we measured the activity of motor areas when the subjects, who were amateur baseball field players (non-pitchers), watched short movie clips of scenes in professional baseball games. The subjects were instructed to support either a batter or a pitcher when observing the movie clip. The results showed that activity in the motor area exhibited a strong interaction between the subject's supported side (batter or pitcher) and the outcome (a hit or an out). When the subject supported the batter, motor area activity was significantly higher when the batter made an out than when he made a hit. However, such modulation was not apparent when the subject supported the pitcher. Conclusions/Significance This result indicates that mirror neuron system activity is modulated by the outcome for a particular player in a competitive game even when observing a complex and naturalistic sports game. We suggest that our inclination to watch competitive games is facilitated by this characteristic of the mirror neuron system. PMID:19946372
Tobin, R. G.
In recent years several baseball players have hit a remarkable number of home runs, and there has been speculation that their achievements were enhanced by the use of anabolic steroids. Basic mechanics and physiology, combined with simple but reasonable models, show that steroid use by a player who is already highly skilled could produce such dramatic increases in home run production. Because home runs are relatively rare events on the tail of a batter's range distribution, even modest changes in bat speed can increase the proportion of batted balls that result in home runs by 50-100%. The possible effect of steroid use by pitchers is briefly considered.
Jinji, Tsutomu; Sakurai, Shinji; Hirano, Yuichi
In this study, we wished to investigate the factors that determine the direction of the spin axis of a pitched baseball. Nineteen male baseball pitchers were recruited to pitch fastballs. The pitching motion was recorded with a three-dimensional motion analysis system (1000 Hz), and the orientations of the hand segment in a global coordinate system were calculated using Euler rotation angles. Reflective markers were attached to the ball, and the direction of the spin axis was calculated on the basis of their positional changes. The spin axis directions were significantly correlated with the orientations of the hand just before ball release. The ball is released from the fingertip and rotates on a plane that is formed by the palm and fingers; the spin axis of the ball is parallel to this plane. The lift force of the pitched baseball is largest when the angular and translational velocity vectors are mutually perpendicular. Furthermore, to increase the lift forces for the fastballs, the palm must face home plate.
MüLler, Sean; Lalović, Alex; Dempsey, Alasdair R; Rosalie, Simon M; Harbaugh, Allen G
This pilot study integrated sport expertise and biomechanics methodologies within a baseball batting task. Purpose was to examine differences within a highly skilled group of baseball batters to use visual information to guide weight transfer and bat movements. One batter who played at Major League Baseball (MLB) level was compared to five batters who played at Australian Baseball League (ABL) level in a case-control design. Batters faced pitchers in a simulated competition and attempted to hit pitches, while vision was temporally occluded during ball flight or not occluded. Time of weight transfer (kinetics), as well as bat downswing initiation and duration (kinematics) from the point of ball release, were compared between the MLB batter and ABL batters. Results indicated that the MLB batter coordinated his striking pattern by completing his weight transfer earlier than the ABL batters. His bat downswing was also initiated earlier than some ABL batters, but there was no difference in duration of bat downswing between batters. All batters initiated bat downswing prior to completion of weight transfer. Understanding of motor expertise is furthered using a novel methodology.
Plant insect interactions are usually recognized as a scenario where herbivorous insects feed on a host plant. However, also the opposite situation is known, where plants feed on insects. Carnivorous pitcher plants of the genus Nepenthes as well as other pitcher plants obtain many nutrients from caught insect prey. Special features of the pitcher traps' surface are responsible for attraction and trapping insects. Once caught, the prey is digested in the fluid of the pitchers to release nutrients and make them available for the plant. Nutrients are taken up by special glands localized on the inner surface of the pitchers. These glands also secrete the hydrolyzing enzymes into the digestion fluid. Although this is known for more than 100 years, our knowledge of the pitcher fluid composition is still limited. Only in recent years some enzymes have been purified from the pitcher fluid and their corresponding genes could be identified. Among them, many pathogenesis-related proteins have been identified, most of which exhibiting hydrolytic activities. The role of these proteins as well as the role of secondary metabolites, which have been identified in the pitcher fluid, is discussed in general and in the context of further studies on carnivorous plants that might give answers to basic questions in plant biology.
Ray, Tracy R
Baseball is a very popular and safe sport for children and adolescents. Understanding bone maturation and risk factors for overuse will guide the practitioner to manage these athletes properly. Overuse injury risk can be minimized by limiting pitch counts, ensuring adequate recovery, developing proper mechanics, and allowing for early evaluation and intervention. Rest, albeit difficult for the athlete, is the mainstay of treatment for many of the maladies affecting this age group of throwers. Individualized approaches to treatment for this population are advised. Structural damage that may lead to surgery is rare but may need consideration if there is no response to conservative measures. Several resources are available to educate players, coaches, and parents regarding safe play.
The trajectory of a baseball moving through the air is very different from the one we teach in our introductory classes in which the only force is that due to gravity. In reality, the aerodynamic drag force (which retards the motion) and the Magnus force on a spinning baseball (which causes the ball to curve) play very important roles that are crucial to many of the subtleties of the game. These forces are governed by three phenomenological quantities: the coefficients of drag, lift, and moment, the latter determining the spin decay time constant. In past years, these quantities were studied mainly in wind tunnel experiments, whereby the forces on the baseball are measured directly. More recently, new tools have been developed that focus on measuring accurate baseball trajectories, from which the forces can be inferred. These tools include high-speed motion analysis, video tracking (the so-called PITCHf/x and HITf/x systems), and Doppler radar tracking via the TrackMan system. In this talk, I will discuss how these new tools work, what they are teaching us about baseball aerodynamics, and how they have the potential to revolutionize the analysis of the game itself.
Hill, Jennifer L; Humphries, Brendan; Weidner, Thomas; Newton, Robert U
Few studies have examined fast-pitch softball pitchers and associated injuries. The aim of this study was to investigate injuries occurring to collegiate softball pitchers and associated influential factors. A web-based survey of 181 Division I (n = 45), II (n = 30), and III (n = 54) collegiate softball pitchers was conducted. The survey involved self-reported data from the previous year that addressed (a) demographic information, (b) pitching and game data, (c) training program information, and (d) injury reporting. Demographic information, pitching and game data, and training program information were not statistically significant (p < 0.05) in relation to injury. Descriptive statistics were used to report totals and percentages of pitchers surveyed. Among 131 reported injuries, 36 were acute, 92 chronic/overuse, and 3 unspecified. Of the total injuries, 80 were directly from pitching, with 33 shoulder-related and 16 related to the lower back. Among injured pitchers, 109 took nonsteroidal anti-inflammatory drugs, 140 used modalities, 11 received surgeries, and 95 saw additional specialists. Pitchers are at a risk for injury, with 72.8% of surveyed pitchers being injured during the 2001-02 year.
Alaways, Leroy Ward
In this dissertation the aerodynamic force and initial conditions of pitched baseballs are estimated from high-speed video data. Fifteen parameters are estimated including the lift coefficient, drag coefficient and the angular velocity vector using a parameter estimation technique that minimizes the residual error between measured and estimated trajectories of markers on the ball's surface and the center of mass of pitched baseballs. Studies are carried out using trajectory data acquired from human pitchers and, in a more controlled environment, with a pitching machine. In all 58 pitch trajectories from human pitchers and 20 pitching machine pitches with spin information are analyzed. In the pitching machine trials four markers on the ball are tracked over the first 4 ft (1.22 m) and the center of mass of the ball is tracked over the last 13 ft (3.96 m) of flight. The estimated lift coefficients are compared to previous measured lift coefficients of Sikorsky (Alaways & Lightfoot, 1998) and Watts & Ferrer (1987) and show that significant differences exists in the lift coefficients of two- and four-seam curve balls at lower values of spin parameter, S. As S increased the two- and four-seam lift coefficients merge becoming statistically insignificant. The estimated drag coefficients are compared to drag coefficients of smooth spheres and golf-balls and show that these data sets bound the drag-coefficient of the baseball. Finally, it is shown that asymmetries of the ball associated with the knuckleball can influence the trajectory of the more common curve and fastball.
Crotin, Ryan L; Bhan, Shivam; Ramsey, Dan K
Motion analyses of lower body mechanics offer new schemas to address injury prevention strategies among baseball pitchers, where the influence of stride length remains unknown. This study examined the temporal effect of stride length at constituent pitching events and phases. Nineteen competitive pitchers (15 collegiate, 4 high school) were randomly assigned to pitch two simulated, 80-pitch games at ±25% of their desired stride length. An integrated, three-dimensional motion capture system recorded each pitch. Paired t-tests were used to determine whether differences between stride conditions at respective events and within phases were significantly different. The results demonstrate the shorter strides mediated earlier onset of stride foot contact, reduced time in single support whereas double support intervals increased (p<.001). The opposite was observed with the longer strides. However, the acceleration phase, which comprises the highest throwing arm kinematics and kinetics, remained unchanged. The interaction between stride length, stride foot contact onsets, and time in single support is inferentially evidenced. The equivalent acceleration phases suggest stride length alone influenced time in single and double support by altering the onset of stride foot contact, which perhaps affects the mechanics in preparing the throwing arm for maximal external shoulder rotation.
Oyama, Sakiko; Sosa, Araceli; Campbell, Rebekah; Correa, Alexandra
Video recordings are used to quantitatively analyze pitchers' techniques. However, reliability and validity of such analysis is unknown. The purpose of the study was to investigate the reliability and validity of joint and segment angles identified during a pitching motion using video analysis. Thirty high school baseball pitchers participated. The pitching motion was captured using 2 high-speed video cameras and a motion capture system. Two raters reviewed the videos to digitize the body segments to calculate 2-dimensional angles. The corresponding 3-dimensional angles were calculated from the motion capture data. Intrarater reliability, interrater reliability, and validity of the 2-dimensional angles were determined. The intrarater and interrater reliability of the 2-dimensional angles were high for most variables. The trunk contralateral flexion at maximum external rotation was the only variable with high validity. Trunk contralateral flexion at ball release, trunk forward flexion at foot contact and ball release, shoulder elevation angle at foot contact, and maximum shoulder external rotation had moderate validity. Two-dimensional angles at the shoulder, elbow, and trunk could be measured with high reliability. However, the angles are not necessarily anatomically correct, and thus use of quantitative video analysis should be limited to angles that can be measured with good validity.
Muto, Tomoyuki; Ninomiya, Hiroki; Inui, Hiroaki; Komai, Masahiko; Nobuhara, Katsuya
In 2013, a 16-year-old baseball pitcher visited Nobuhara Hospital complaining of shoulder pain and limited range of motion in his throwing shoulder. High signal intensity in the rotator interval (RI) area (ball sign), injured subscapularis tendon, and damage to both the superior and middle glenohumeral ligaments were identified using magnetic resonance imaging (MRI). Repair of the RI lesion and partially damaged subscapularis tendon was performed in this pitcher. During surgery, an opened RI and dropping of the subscapularis tendon were observed. The RI was closed in a 90° externally rotated and abducted position. To reconfirm the exact repaired state of the patient, arthroscopic examination was performed from behind. However, suture points were not visible in the >30° externally rotated position, which indicates that the RI could not be correctly repaired with the arthroscopic procedure. One year after surgery, the patient obtained full function of the shoulder and returned to play at a national convention. Surgical repair of the RI lesion should be performed in exactly the correct position of the upper extremity. PMID:26618017
Fukushima, Kenji; Fujita, Hironori; Yamaguchi, Takahiro; Kawaguchi, Masayoshi; Tsukaya, Hirokazu; Hasebe, Mitsuyasu
Complex morphology is an evolutionary outcome of phenotypic diversification. In some carnivorous plants, the ancestral planar leaf has been modified to form a pitcher shape. However, how leaf development was altered during evolution remains unknown. Here we show that the pitcher leaves of Sarracenia purpurea develop through cell division patterns of adaxial tissues that are distinct from those in bifacial and peltate leaves, subsequent to standard expression of adaxial and abaxial marker genes. Differences in the orientation of cell divisions in the adaxial domain cause bifacial growth in the distal region and adaxial ridge protrusion in the middle region. These different growth patterns establish pitcher morphology. A computer simulation suggests that the cell division plane is critical for the pitcher morphogenesis. Our results imply that tissue-specific changes in the orientation of cell division underlie the development of a morphologically complex leaf.
Fukushima, Kenji; Fujita, Hironori; Yamaguchi, Takahiro; Kawaguchi, Masayoshi; Tsukaya, Hirokazu; Hasebe, Mitsuyasu
Complex morphology is an evolutionary outcome of phenotypic diversification. In some carnivorous plants, the ancestral planar leaf has been modified to form a pitcher shape. However, how leaf development was altered during evolution remains unknown. Here we show that the pitcher leaves of Sarracenia purpurea develop through cell division patterns of adaxial tissues that are distinct from those in bifacial and peltate leaves, subsequent to standard expression of adaxial and abaxial marker genes. Differences in the orientation of cell divisions in the adaxial domain cause bifacial growth in the distal region and adaxial ridge protrusion in the middle region. These different growth patterns establish pitcher morphology. A computer simulation suggests that the cell division plane is critical for the pitcher morphogenesis. Our results imply that tissue-specific changes in the orientation of cell division underlie the development of a morphologically complex leaf. PMID:25774486
Rottloff, Sandy; Miguel, Sissi; Biteau, Flore; Nisse, Estelle; Hammann, Philippe; Kuhn, Lauriane; Chicher, Johana; Bazile, Vincent; Gaume, Laurence; Mignard, Benoit; Hehn, Alain; Bourgaud, Frédéric
Background and Aims Carnivorous plants have developed strategies to enable growth in nutrient-poor soils. For the genus Nepenthes, this strategy represents producing pitcher-modified leaves that can trap and digest various prey. These pitchers produce a digestive fluid composed of proteins, including hydrolytic enzymes. The focus of this study was on the identification of these proteins. Methods In order to better characterize and have an overview of these proteins, digestive fluid was sampled from pitchers at different stages of maturity from five species of Nepenthes (N. mirabilis, N. alata, N. sanguinea, N. bicalcarata and N. albomarginata) that vary in their ecological niches and grew under different conditions. Three complementary approaches based on transcriptomic resources, mass spectrometry and in silico analysis were used. Key Results This study permitted the identification of 29 proteins excreted in the pitchers. Twenty of these proteins were never reported in Nepenthes previously and included serine carboxypeptidases, α- and β-galactosidases, lipid transfer proteins and esterases/lipases. These 20 proteins display sequence signals allowing their secretion into the pitcher fluid. Conclusions Nepenthes pitcher plants have evolved an arsenal of enzymes to digest prey caught in their traps. The panel of new proteins identified in this study provides new insights into the digestive process of these carnivorous plants. PMID:26912512
Chou, Lee Yiung; Dykes, Gary A; Wilson, Robyn F; Clarke, Charles M
Nepenthes pitcher plants are colonized by a variety of specialized arthropods. As Aedes mosquitoes are container breeders, Nepenthes pitchers are a potential candidate oviposition site for vector species, such as Aedes aegypti (L.) and Aedes albopictus (Skuse). However, Aedes spp. are not commonly encountered in Nepenthes pitchers, and the environment inside the pitchers of some species is lethal to them. One exception is Nepenthes ampullaria Jack, whose pitchers are known to be colonized by Ae. albopictus on very rare occasions. Given that Ae. albopictus larvae can survive in N. ampullaria pitcher fluids, we sought to determine why pitcher colonization is rare, testing the hypothesis that gravid Aedes mosquitoes are deterred from ovipositing into container habitats that have similar characteristics to N. ampullaria pitchers. Using plastic ovitraps of different sizes, colors, and with different types of fluids (based on the characteristics of N. ampullaria pitchers), we compared oviposition rates by Aedes mosquitoes in urban and rural areas within the geographical range of N. ampullaria near Kuala Lumpur, Malaysia. Ovitraps that were black and large (>250-ml capacity) accumulated significantly more eggs than ovitraps that were smaller, or green in color. In terms of size and color, small, green ovitraps are analogous to N. ampullaria pitchers, indicating that these pitchers are not particularly attractive to gravid Ae. albopictus. Although Aedes spp. are capable of colonizing N. ampullaria pitchers, the pitchers are relatively unattractive to gravid females and do not represent a significant habitat for larvae of dengue vectors at present.
Bryant, D. D.; Greenfield, R.; Martin, E.
Between July 1987 and December 1990 in Washington, DC, 116 patients sustained 146 fractures and seven dislocations due to an assault with a baseball bat. The ulna was the most common site of trauma (61 fractures), followed by the hand (27 injuries) and the radius (14 injuries). Forty-two of the 146 fractures were significantly displaced and required open reduction and internal fixation to restore satisfactory alignment. Twenty-nine of the 146 fractures were open fractures. Treatment protocol for open fractures consisted of irrigation and debridement, antibiotic therapy, and bone stabilization with either internal or external fixation, or casting. Recognition of the severity of the soft tissue and bone damage is important in the management of musculoskeletal trauma secondary to the baseball bat. Images Figure 1 Figure 2 Figure 3 PMID:1460683
Dawson, W J; Pullos, N
We conducted an epidemiological and etiological study of softball injuries to the hand in order to inform emergency medicine personnel of the high frequency and causative factors of these injuries. Injuries to the hand and fingers from baseball and softball comprised 2.2% of emergency department visits during this study. Most frequent injuries were: 1) sprain and sprain-fracture of the proximal IP joint (31.6%); and 2) the so-called "mallet" or "baseball finger" injury to the distal joint (18.9%). The 16-inch softball was the cause of more than two-thirds of all these injuries, most of which occurred in patients between the ages of 11 and 30. Treatment recommendations are beyond the scope of this article.
Buffi, James H.; Werner, Katie; Kepple, Tom; Murray, Wendy M.
Baseball pitching imposes a dangerous valgus load on the elbow that puts the joint at severe risk for injury. The goal of this study was to develop a musculoskeletal modeling approach to enable evaluation of muscle-tendon contributions to mitigating elbow injury risk in pitching. We implemented a forward dynamic simulation framework that used a scaled biomechanical model to reproduce a pitching motion recorded from a high school pitcher. The medial elbow muscles generated substantial, protective, varus elbow moments in our simulations. For our subject, the triceps generated large varus moments at the time of peak valgus loading; varus moments generated by the flexor digitorum superficialis were larger, but occurred later in the motion. Increasing muscle-tendon force output, either by augmenting parameters associated with strength and power or by increasing activation levels, decreased the load on the ulnar collateral ligament. Published methods have not previously quantified the biomechanics of elbow muscles during pitching. This simulation study represents a critical advancement in the study of baseball pitching and highlights the utility of simulation techniques in the study of this difficult problem. PMID:25281409
Buffi, James H; Werner, Katie; Kepple, Tom; Murray, Wendy M
Baseball pitching imposes a dangerous valgus load on the elbow that puts the joint at severe risk for injury. The goal of this study was to develop a musculoskeletal modeling approach to enable evaluation of muscle-tendon contributions to mitigating elbow injury risk in pitching. We implemented a forward dynamic simulation framework that used a scaled biomechanical model to reproduce a pitching motion recorded from a high school pitcher. The medial elbow muscles generated substantial, protective, varus elbow moments in our simulations. For our subject, the triceps generated large varus moments at the time of peak valgus loading; varus moments generated by the flexor digitorum superficialis were larger, but occurred later in the motion. Increasing muscle-tendon force output, either by augmenting parameters associated with strength and power or by increasing activation levels, decreased the load on the ulnar collateral ligament. Published methods have not previously quantified the biomechanics of elbow muscles during pitching. This simulation study represents a critical advancement in the study of baseball pitching and highlights the utility of simulation techniques in the study of this difficult problem.
Bauer, Ulrike; Di Giusto, Bruno; Skepper, Jeremy; Grafe, T Ulmar; Federle, Walter
Carnivorous pitcher plants capture prey with modified leaves (pitchers), using diverse mechanisms such as 'insect aquaplaning' on the wet pitcher rim, slippery wax crystals on the inner pitcher wall, and viscoelastic retentive fluids. Here we describe a new trapping mechanism for Nepenthes gracilis which has evolved a unique, semi-slippery wax crystal surface on the underside of the pitcher lid and utilises the impact of rain drops to 'flick' insects into the trap. Depending on the experimental conditions (simulated 'rain', wet after 'rain', or dry), insects were captured mainly by the lid, the peristome, or the inner pitcher wall, respectively. The application of an anti-slip coating to the lower lid surface reduced prey capture in the field. Compared to sympatric N. rafflesiana, N. gracilis pitchers secreted more nectar under the lid and less on the peristome, thereby directing prey mainly towards the lid. The direct contribution to prey capture represents a novel function of the pitcher lid.
Williams, Emyr W.; Romar, Jan-Erik; Hartman, Michael
Both British and Finnish baseball are easy to introduce, as the specific skills involved in both sports are identical to those used in traditional baseball. If students have the skills to play traditional baseball, they have the skills to play British and Finnish baseball as well. After a brief overview of the unique rules and strategies of these…
Three bilingual booklets are presented listing technical terms for golf and baseball. The golf terms are in French-English and Spanish-English lists; the baseball terms are in French-English. The French terms are taken from French-Canadian newspapers, books, and periodicals, while the Spanish terms are taken from Mexican newspapers, books, and…
Oliver, Gretchen D; Plummer, Hillary A; Washington, Jessie; Weimar, Wendi H; Brambeck, Allison
The purpose of this study was to examine the effects of game exposure on pitchers and catchers' hip and glenohumeral range of motion (ROM), isometric strength, and vertical jump performance and power. Five college female softball pitchers (174.24 ± 7.53 cm; 82.10 ± 11.27 kg; 20 ± 1.82 years) and four catchers (165.10 ± 9.04 kg; 68.61 ± 3.87 cm; 20 ± 1.41 years) participated. Hip and glenohumeral rotational ROM; hip and glenohumeral rotational isometric strength; hip abduction and adduction strength; and vertical jump height were assessed pre and post-game exposure. The catchers displayed significantly greater throwing side hip IR ROM (Mean Difference = +6.88°, p=0.03) post-game exposure, while the pitchers exhibited less IR (Mean Difference = -2.02%, p = .013) and ER (Mean Difference = -1.95%, p = .026) strength in the non-throwing side hip pre versus post-game exposure. The performance demands of pitchers and catchers vary greatly, causing position specific decreases/increases in various tests following game performance. Pitchers exhibited significant decreases in non-throwing side hip IR and ER strength. In catchers, throwing side hip IR range of motion significantly increased following game exposure. Further evaluation of ROM, strength, and power is necessary as it is unknown how these changes following a game affect sports performance or risk of injury.
Carnivorous pitcher plants of the genus Nepenthes capture prey with a pitfall trap that relies on a micro-structured, slippery surface. The upper pitcher rim (peristome) is fully wettable and causes insects to slip by aquaplaning on a thin water film. The high wettability of the peristome is probably achieved by a combination of hydrophilic surface chemistry, surface roughness and the presence of hygroscopic nectar. Insect foot attachment could be prevented by the delayed drainage of the thin water film between the adhesive pad and the surface. Drainage should be faster for insects with a hairy adhesive system; however, they slip equally on the wet peristome. Therefore the stability of the water film against dewetting appears to be the key factor for aquaplaning. New experimental techniques may help to clarify the detailed function of the pitcher plant peristome and to explore its potential for biomimetic applications. PMID:20009546
Pavlovič, Andrej; Masarovičová, Elena; Hudák, Ján
Background and Aims Pitcher plants Nepenthes alata and N. mirabilis are carnivorous species with leaves composed of a photosynthetic part (lamina) and a pitcher trap. This characteristic permitted direct physiological and anatomical comparison between these two distinct parts of the leaves to determine those features involved in the ‘carnivorous syndrome’, which include low net photosynthetic assimilation rate (AN) and low photosynthetic nitrogen use efficiency (PNUE). Methods Photosynthetic rate (AN) and respiration rate (Rd) were measured gasometrically, chlorophyll concentration was determined spectrophotometrically and nitrogen concentration was determined using a CHN elemental analyser in lamina and trap separately. Anatomy of N. alata was observed using light, fluorescence and transmission electron microscopy. AN, foliar nitrogen and chlorophyll concentration were also compared with values for other carnivorous plant species (genera Sarracenia, Drosera) that combine both autotrophic and carnivorous functions into the same physical organ. Key Results It was found that the AN in Nepenthes lamina was low and PNUE was only slightly higher or similar in comparison with other carnivorous plants. It was not observed that the pitcher had a higher Rd than the lamina, but AN in the pitcher was significantly lower than in the lamina. Nepenthes possesses a cluster of characters that could result in reduced photosynthesis in the pitcher and be responsible for carnivorous function of the leaf: replacement of chlorophyll-containing cells with digestive glands, low chlorophyll and nitrogen concentration, compact mesophyll with a small portion of intercellular spaces, absence of palisade parenchyma and low stomatal density. Conclusion Low photosynthetic capacity, nitrogen efficiency, chlorophyll and nitrogen concentration of Nepenthes pitchers was found, together with a set of features that characterized the carnivorous syndrome. Dual use of leaves for photosynthesis and
Bauer, Ulrike; Grafe, T Ulmar; Federle, Walter
Nepenthes pitchers are specialized leaves that function as insect traps. Several pitcher components may contribute to trapping, including the pitcher fluid, slippery wax crystals and downward-pointing epidermal cells on the inner pitcher wall, and the wetness-dependent pitcher rim (peristome), but the relative importance of these traits is unclear. Mechanisms of prey capture and retention in the field were investigated by quantifying the effect of 'knock-out' manipulations of individual pitcher structures, and by testing the ability of pitcher fluids and water to retain insects. Two forms of Nepenthes rafflesiana Jack ('elongate' and 'typical') with contrasting combinations of pitcher traits were compared. Wax crystals on the inner pitcher wall were found to be the most important trapping structure in the elongate form, whereas the typical form relied primarily on the peristome. The pitcher fluids of both forms, differing markedly in the degree of viscoelasticity, retained significantly more ants than water. The present results show that pitcher plants utilize several mechanisms for prey capture and retention, varying in efficiency and relative importance between forms. It is proposed that these differences represent alternative prey capture strategies that may provide a mechanism to reduce competition and facilitate species co-existence in nutrient-limited habitats.
Pinthong, Krit; Chaveerach, Arunrat; Tanee, Tawatchai; Sudmoon, Runglawan; Mokkamul, Piya
Nepenthes gracilis Korth. is a member of carnivorous plants in family Nepenthaceae. The plants have beautiful and economically important pitchers. It is interesting to study the protein(s) correlated with the pitcher. Crude proteins were extracted from leaf, leaf with developing pitcher and developed pitcher of the same plant and analyzed by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Two protein bands with molecular weights of 42.7 and 38 kDa were obtained from young leaf and leaf with developing pitcher, respectively. The 42.7 kDa protein was identified as phosphoglycerate kinase (PGK) by Liquid Chromatography Mass Spectrometry (LC-MS/MS), but the 38 kDa band is an unknown protein. Both proteins were differentially expressed in each developing stage of the pitcher, thus may be powerful candidates play role in development pathway of leaf and pitcher.
Moran, Jonathan A; Hawkins, Barbara J; Gowen, Brent E; Robbins, Samantha L
Nepenthes pitcher plant species differ in their prey capture strategies, prey capture rates, and pitcher longevity. In this study, it is investigated whether or not interspecific differences in nutrient sequestration strategy are reflected in the physiology and microstructure of the pitchers themselves. Using a non-invasive technique (MIFE), ion fluxes in pitchers of Nepenthes ampullaria Jack, Nepenthes bicalcarata Hook.f., and Nepenthes rafflesiana Jack were measured. Scanning electron microscopy was also used to characterize the distribution of glandular and other structures on the inner pitcher walls. The results demonstrate that nutrient sequestration strategy is indeed mirrored in pitcher physiology and microstructure. Species producing long-lived pitchers with low prey capture rates (N. ampullaria, N. bicalcarata) showed lower rates of NH(4)(+) uptake than N. rafflesiana, a species producing short-lived pitchers with high capture rates. Crucially, species dependent upon aquatic commensals (N. ampullaria, N. bicalcarata) actively manipulated H(+) fluxes to maintain less acid pitcher fluid than found in 'typical' species; in addition, these species lacked the lunate cells and epicuticular waxes characteristic of 'typical' insectivorous congeners. An unexpected finding was that ion fluxes occurred in the wax-covered, non-glandular zones in N. rafflesiana. The only candidates for active transport of aqueous ions in these zones appear to be the epidermal cells lying beneath the lunate cells, as these are the only sites not visibly coated with epicuticular waxes.
Morphological correlates of necromass accumulation in the traps of an Eastern tropical pitcher plant, Nepenthes ampullaria Jack, and observations on the pitcher infauna and its reconstitution following experimental removal.
Cresswell, James E
I studied the trap morphology, necromass accumulation rates and pitcher infauna of an eastern tropical pitcher plant, Nepenthes ampullaria, that grew in `kerangas' heath forest in the Sungei Ingei Conservation Area, Brunei. I surveyed 164 pitchers distributed among 35 plants and extracted the necromass and larval infauna from the pitchers and then resampled the pitcher contents after 14 days. Plants varied significantly in the morphology of their pitchers, in their rate of necromass accumulation per pitcher and in the abundance and composition of the pitcher infaunas. On average, pitchers accumulated 11.5 mg dry weight over 14 days, but larger pitchers accumulated more necromass than smaller ones. Pitcher morphology explained 45% of the variation in necromass accumulation among plants. On average, pitchers initially contained 26.3 individual larval inquilines. Collectively, the larval infauna was composed of nine taxa of dipteran larvae and infrequent anuran tadpoles. These ten taxa were never found together in a single pitcher and the mean species richness per pitcher was 4.0. Of the six taxa that could be assessed, all except Toxorhynchites spp. had a contagious distribution among the pitchers. Pitcher morphology and necromass accumulation explained only 15% of the variation in inquiline abundance among plants. I found little evidence for the existence of density-dependent interactions between inquiline species: a partial correlation analysis detected only one statistically significant pairwise relationship between the abundances of inquiline taxa, which was a positive association. Fourteen days after being emptied, pitchers contained an average of 9.6 inquilines. There was no evidence that the species composition of the infauna recolonising each pitcher was related to that of its pre-removal infauna.
Chan, Xin-Yue; Hong, Kar-Wai; Yin, Wai-Fong; Chan, Kok-Gan
Tropical carnivorous plant, Nepenthes, locally known as "monkey cup", utilises its pitcher as a passive trap to capture insects. It then secretes enzymes into the pitcher fluid to digest the insects for nutrients acquisition. However, little is known about the microbiota and their activity in its pitcher fluid. Eighteen bacteria phyla were detected from the metagenome study in the Nepenthes pitcher fluid. Proteobacteria, Bacteroidetes and Actinobacteria are the dominant phyla in the Nepenthes pitcher fluid. We also performed culturomics approach by isolating 18 bacteria from the Nepenthes pitcher fluid. Most of the bacterial isolates possess chitinolytic, proteolytic, amylolytic, and cellulolytic and xylanolytic activities. Fifteen putative chitinase genes were identified from the whole genome analysis on the genomes of the 18 bacteria isolated from Nepenthes pitcher fluid and expressed for chitinase assay. Of these, six clones possessed chitinase activity. In conclusion, our metagenome result shows that the Nepenthes pitcher fluid contains vast bacterial diversity and the culturomic studies confirmed the presence of biocatalytic bacteria within the Nepenthes pitcher juice which may act in symbiosis for the turn over of insects trapped in the Nepenthes pitcher fluid.
Chan, Xin-Yue; Hong, Kar-Wai; Yin, Wai-Fong; Chan, Kok-Gan
Tropical carnivorous plant, Nepenthes, locally known as “monkey cup”, utilises its pitcher as a passive trap to capture insects. It then secretes enzymes into the pitcher fluid to digest the insects for nutrients acquisition. However, little is known about the microbiota and their activity in its pitcher fluid. Eighteen bacteria phyla were detected from the metagenome study in the Nepenthes pitcher fluid. Proteobacteria, Bacteroidetes and Actinobacteria are the dominant phyla in the Nepenthes pitcher fluid. We also performed culturomics approach by isolating 18 bacteria from the Nepenthes pitcher fluid. Most of the bacterial isolates possess chitinolytic, proteolytic, amylolytic, and cellulolytic and xylanolytic activities. Fifteen putative chitinase genes were identified from the whole genome analysis on the genomes of the 18 bacteria isolated from Nepenthes pitcher fluid and expressed for chitinase assay. Of these, six clones possessed chitinase activity. In conclusion, our metagenome result shows that the Nepenthes pitcher fluid contains vast bacterial diversity and the culturomic studies confirmed the presence of biocatalytic bacteria within the Nepenthes pitcher juice which may act in symbiosis for the turn over of insects trapped in the Nepenthes pitcher fluid. PMID:26817720
Maintaining that baseball presents a view of American society in microcosm, this article reviews the Cold War history of American baseball, showing how the statements and concerns of the players and managers reflected popular values of that era. (JDH)
Abbott, Matthew J.; Battaglia, Loretta L.
Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change. PMID:25874369
Abbott, Matthew J; Battaglia, Loretta L
Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change.
Moran, Jonathan A; Clarke, Charles; Gowen, Brent E
Nepenthes pitcher plants deploy tube-shaped pitchers to catch invertebrate prey; those of Nepenthes aristolochioides possess an unusual translucent dome. The hypothesis was tested that N. aristolochioides pitchers operate as light traps, by quantifying prey capture under three shade treatments. Flies are red-blind, with visual sensitivity maxima in the UV, blue, and green wavebands. Red celluloid filters were used to reduce the transmission of these wavebands into the interior of the pitchers. Those that were shaded at the rear showed a 3-fold reduction in Drosophila caught, relative to either unshaded control pitchers, or pitchers that were shaded at the front. Thus, light transmitted through the translucent dome is a fundamental component of N. aristolochioides' trapping mechanism.
Cooper, B. Lee; Walker, Donald E.
Argues that using popular recordings that feature baseball imagery is an innovative way to introduce students to the pluralistic nature of U.S. life. Outlines a variety of themes that use baseball history to develop concepts about social change, cultural values, and individual achievement. Lists audio recordings that have baseball themes. (DB)
From little league players to professional athletes, baseball has become a sport that is not only fun to play and watch, but also a sport driven by innovation and technology. One particular piece of baseball equipment that has undergone many changes is the baseball bat. Prior to the early 1970s, wooden bats were the only choice available. Today,…
Baseball and softball bats are sold according to length in inches and weight in ounces. Much to the consternation of players buying new bats, however, not all bats that weigh the same swing the same. The reason for this has to do with moment of inertia of the bat about a pivot point on the handle, or what the sporting goods industry refers to as swing weight.2-3 A number of recent field studies4-7 have confirmed that the speed with which a player can swing a baseball or softball bat depends more on the bat's moment of inertia than on its mass. In this paper we investigate the moment of inertia (swing weight) of a variety of baseball and softball bats.
Meyer, Edmund R.; Bohn, John L.
We investigate whether storing baseballs in a controlled humidity environment significantly affects their aerodynamic properties. We measure the change in diameter and weight of baseballs as a function of relative humidity in which the balls are stored. The trajectories of pitched and batted baseballs are modeled to assess the difference between those stored at 30% relative humidity versus 50% relative humidity. We find that a drier baseball will curve slightly more than a humidified one for a given pitch velocity and rotation rate. We also find that aerodynamics alone would add 2ft to the distance a wetter baseball ball is hit. This increased distance is compensated by a 6ft reduction in the batted distance due to the change in the coefficient of restitution of the ball. We discuss consequences of these results for baseball played at Coors Field in Denver, where baseballs have been stored in a humidor at 50% relative humidity since 2002.
Scharmann, Mathias; Thornham, Daniel G; Grafe, T Ulmar; Federle, Walter
Many plants combat herbivore and pathogen attack indirectly by attracting predators of their herbivores. Here we describe a novel type of insect-plant interaction where a carnivorous plant uses such an indirect defence to prevent nutrient loss to kleptoparasites. The ant Camponotus schmitzi is an obligate inhabitant of the carnivorous pitcher plant Nepenthes bicalcarata in Borneo. It has recently been suggested that this ant-plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N. bicalcarata host plant leaves naturally have an elevated (15)N/(14)N stable isotope abundance ratio (δ(15)N) when colonised by C. schmitzi. This indicates that a higher proportion of the plants' nitrogen is insect-derived when C. schmitzi ants are present (ca. 100%, vs. 77% in uncolonised plants) and that more nitrogen is available to them. We demonstrated direct flux of nutrients from the ants to the host plant in a (15)N pulse-chase experiment. As C. schmitzi ants only feed on nectar and pitcher contents of their host, the elevated foliar δ(15)N cannot be explained by classic ant-feeding (myrmecotrophy) but must originate from a higher efficiency of the pitcher traps. We discovered that C. schmitzi ants not only increase the pitchers' capture efficiency by keeping the pitchers' trapping surfaces clean, but they also reduce nutrient loss from the pitchers by predating dipteran pitcher inhabitants (infauna). Consequently, nutrients the pitchers would have otherwise lost via emerging flies become available as ant colony waste. The plants' prey is therefore conserved by the ants. The interaction between C. schmitzi, N. bicalcarata and dipteran pitcher infauna represents a new type of mutualism where animals mitigate the damage by nutrient thieves to a plant.
Gaume, Laurence; Bazile, Vincent; Huguin, Maïlis; Bonhomme, Vincent
Nepenthes pitcher plants display interspecific diversity in pitcher form and diets. This species-rich genus might be a conspicuous candidate for an adaptive radiation. However, the pitcher traits of different species have never been quantified in a comparative study, nor have their possible adaptations to the resources they exploit been tested. In this study, we compare the pitcher features and prey composition of the seven Nepenthes taxa that grow in the heath forest of Brunei (Borneo) and investigate whether these species display different trapping syndromes that target different prey. The Nepenthes species are shown to display species-specific combinations of pitcher shapes, volumes, rewards, attraction and capture traits, and different degrees of ontogenetic pitcher dimorphism. The prey spectra also differ among plant species and between ontogenetic morphotypes in their combinations of ants, flying insects, termites, and noninsect guilds. According to a discriminant analysis, the Nepenthes species collected at the same site differ significantly in prey abundance and composition at the level of order, showing niche segregation but with varying degrees of niche overlap according to pairwise species comparisons. Weakly carnivorous species are first characterized by an absence of attractive traits. Generalist carnivorous species have a sweet odor, a wide pitcher aperture, and an acidic pitcher fluid. Guild specializations are explained by different combinations of morpho-functional traits. Ant captures increase with extrafloral nectar, fluid acidity, and slippery waxy walls. Termite captures increase with narrowness of pitchers, presence of a rim of edible trichomes, and symbiotic association with ants. The abundance of flying insects is primarily correlated with pitcher conicity, pitcher aperture diameter, and odor presence. Such species-specific syndromes favoring resource partitioning may result from local character displacement by competition and/or previous
Scahill, Edward M.
Advocates using baseball statistics to illustrate the advantages of specialization in production. Using Babe Ruth's record as an analogy, suggests a methodology for determining a player's comparative advantage as a teaching illustration. Includes the team's statistical profile in five tables to explain comparative advantage and profit maximizing.…
Whiteside, D; McGinnis, R S; Deneweth, J M; Zernicke, R F; Goulet, G C
The purpose of this study was to quantify ball flight kinematics (ball speed, spin rate, spin axis orientation, seam orientation) and release location variability in the four most common pitch types in baseball and relate them to in-season pitching performance. Nine NCAA Division I pitchers threw four pitching variations (fastball, changeup, curveball, and slider) while a radar gun measured ball speed and a 600-Hz video camera recorded the ball trajectory. Marks on the ball were digitized to measure ball flight kinematics and release location. Ball speed was highest in the fastball, though spin rate was similar in the fastball and breaking pitches. Two distinct spin axis orientations were noted: one characterizing the fastball and changeup, and another, the curveball and slider. The horizontal release location was significantly more variable than the vertical release location. In-season pitching success was not correlated to any of the measured variables. These findings are instructive for inferring appropriate hand mechanics and spin types in each of the four pitches. Coaches should also be aware that ball flight kinematics might not directly relate to pitching success at the collegiate level. Therefore, talent identification and pitching evaluations should encompass other (e.g., cognitive, psychological, and physiological) factors.
Nagami, Tomoyuki; Higuchi, Takatoshi; Nakata, Hiroki; Yanai, Toshimasa; Kanosue, Kazuyuki
Although the lift force (F(L)) on a spinning baseball has been analyzed in previous studies, no study has analyzed such forces over a wide variety of spins. The purpose of this study was to describe the relationship between F(L) and spin for different types of pitches thrown by collegiate pitchers. Four high-speed video cameras were used to record flight trajectory and spin for 7 types of pitches. A total of 75 pitches were analyzed. The linear kinematics of the ball was determined at 0.008-s intervals during the flight, and the resultant fluid force acting on the ball was calculated with an inverse dynamics approach. The initial angular velocity of the ball was determined using a custom-made apparatus. Equations were derived to estimate the F(L) using the effective spin parameter (ESp), which is a spin parameter calculated using a component of angular velocity of the ball with the exception of the gyro-component. The results indicate that F(L) could be accurately explained from ESp and also that seam orientation (4-seam or 2-seam) did not produce a uniform effect on estimating F(L) from ESp.
An, Chung-Il; Takekawa, Shoji; Okazawa, Atsushi; Fukusaki, Ei-Ichiro; Kobayashi, Akio
Carnivorous plants acquire substantial amounts of nitrogen from insects. The tropical carnivorous plant Nepenthes produces trapping organs called pitchers at the tips of tendrils elongated from leaf ends. Acidic fluid is secreted at the bottoms of the pitchers. The pitcher fluid includes several hydrolytic enzymes, and some, such as aspartic proteinase, are thought to be involved in nitrogen acquisition from insect proteins. To understand the nitrogen-acquisition process, it is essential to identify the protein-degradation products in the pitcher fluid. To gain insight into protein degradation in pitcher fluid, we used the oxidized B-chain of bovine insulin as a model substrate, and its degradation by the pitcher fluid of N. alata was investigated using liquid chromatography-mass spectrometry (LC-MS). LC-MS analysis of the degradation products revealed that the oxidized B-chain of bovine insulin was initially cleaved at aromatic amino acids such as phenylalanine and tyrosine. These cleavage sites are similar to those of aspartic proteinases from other plants and animals. The presence of a series of peptide fragments as degradation products suggests that exopeptidase(s) is also present in the pitcher fluid. Amino acid analysis and peptide fragment analysis of the degradation products demonstrated that three amino acids plus small peptides were released from the oxidized B-chain of bovine insulin, suggesting that insect proteins are readily degraded to small peptides and amino acids in the pitcher fluid of N. alata.
Lam, Weng Ngai; Chong, Kwek Yan; Anand, Ganesh S; Tan, Hugh Tiang Wah
The fluid-containing traps of Nepenthes carnivorous pitcher plants (Nepenthaceae) are often inhabited by organisms known as inquilines. Dipteran larvae are key components of such communities and are thought to facilitate pitcher nitrogen sequestration by converting prey protein into inorganic nitrogen, although this has never been demonstrated in Nepenthes Pitcher fluids are also inhabited by microbes, although the relationship(s) between these and the plant is still unclear. In this study, we examined the hypothesis of digestive mutualism between N. gracilis pitchers and both dipteran larvae and fluid microbes. Using dipteran larvae, prey and fluid volumes mimicking in situ pitcher conditions, we conducted in vitro experiments and measured changes in available fluid nitrogen in response to dipteran larvae and microbe presence. We showed that the presence of dipteran larvae resulted in significantly higher and faster releases of ammonium and soluble protein into fluids in artificial pitchers, and that the presence of fluid microbes did likewise for ammonium. We showed also that niche segregation occurs between phorid and culicid larvae, with the former fragmenting prey carcasses and the latter suppressing fluid microbe levels. These results clarify the relationships between several key pitcher-dwelling organisms, and show that pitcher communities facilitate nutrient sequestration in their host.
Peterson, Celeste N; Day, Stephanie; Wolfe, Benjamin E; Ellison, Aaron M; Kolter, Roberto; Pringle, Anne
The community of organisms inhabiting the water-filled leaves of the carnivorous pitcher-plant Sarracenia purpurea includes arthropods, protozoa and bacteria, and serves as a model system for studies of food web dynamics. Despite the wealth of data collected by ecologists and zoologists on this food web, very little is known about the bacterial assemblage in this microecosystem. We used terminal restriction fragment length polymorphism (T-RFLP) analysis to quantify bacterial diversity within the pitchers as a function of pitcher size, pH of the pitcher fluid and the presence of the keystone predator in this food web, larvae of the pitcher-plant mosquito Wyeomyia smithii. Results were analysed at two spatial scales: within a single bog and across three isolated bogs. Pitchers were sterile before they opened and composition of the bacterial assemblage was more variable between different bogs than within bogs. Measures of bacterial richness and diversity were greater in the presence of W. smithii and increased with increasing pitcher size. Our results suggest that fundamental ecological concepts derived from macroscopic food webs can also be used to predict the bacterial assemblages in pitcher plants.
Castaneda, Lupe; Sherrill, Claudine
Describes how two disability sports programs, Little League Baseball's Challenger Division and TOPSoccer (The Outreach Program for Soccer), are being implemented in Arlington, Texas. Both programs are intended to include children and youth with physical or mental disabilities and to increase family involvement. Summarized are game rules, outcomes…
Blue Jeans Baseball, for eight- to twelve-year old children, is based on the concept that everyone plays. No coaches are allowed; everyone bats once per inning; defensive players rotate positions. These and other rules reduce the emphasis on competition and increase the emphasis on skill development. (MJB)
Eisner, Milton P.
Uses conic sections, trigonometric functions, and polar coordinates to solve the problem of determining the shape of a baseball outfield fence, given the distances along the foul lines and to straightaway center field. Graphing programs and calculators are utilized to plot different solutions. (MDH)
Edwards, R. A. R.
This article begins by examining the historical and social factors that led to 1901 being the "deafest" year in major league baseball history with four deaf players. In particular, the author discusses the career of William Ellsworth "Dummy" Hoy, a deaf man from Ohio who became the most celebrated deaf player in history and…
This pamphlet is an alphabetical English-Spanish listing of more than three hundred words, phrases, and sentences related to the game of baseball as it is reported in Mexico City, in border towns, and in Spanish language newspapers in the United States. At the end of this dictionary are listed the major league teams of the United States and Canada…
Kagan, David; Nathan, Alan M.
Baseball's flirtation with technology began in 2005 when PITCHf/x® by Sportvision started to be installed in major league ballparks. Every stadium had the system operational by 2007. Since then, the trajectories of over six million pitches have been measured to within about half an inch using three 60-Hz video cameras to track the position of the ball.
Hatano, Naoya; Hamada, Tatsuro
The genus Nepenthes comprises carnivorous plants that digest insects in pitcher fluid to supplement their nitrogen uptake. In a recent study, two acid proteinases (nepenthesins I and II) were purified from the pitcher fluid. However, no other enzymes involved in prey digestion have been identified, although several enzyme activities have been reported. To identify all the proteins involved, we performed a proteomic analysis of Nepenthes pitcher fluid. The secreted proteins in pitcher fluid were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and several protein bands were detected by silver staining. The proteins were identified by in-gel tryptic digestion, de novo peptide sequencing, and homology searches against public databases. The proteins included homologues of beta-D-xylosidase, beta-1,3-glucanase, chitinase, and thaumatin-like protein, most of which are designated "pathogenesis-related proteins". These proteins presumably inhibit bacterial growth in the pitcher fluid to ensure sufficient nutrients for Nepenthes growth.
Grafe, T Ulmar; Schöner, Caroline R; Kerth, Gerald; Junaidi, Anissa; Schöner, Michael G
Mutualistic relationships between vertebrates and plants apart from the pollen and seed-dispersal syndromes are rare. At first view, carnivorous pitcher plants of the genus Nepenthes seem to be highly unlikely candidates for mutualistic interactions with animals, as they form dimorphic terrestrial and aerial pitchers that trap arthropods and small vertebrates. Surprisingly, however, the aerial pitchers of Nepenthes rafflesiana variety elongata are poor insect traps, with low amounts of insect-attractive volatile compounds and low amounts of digestive fluid. Here, we show that N. rafflesiana elongata gains an estimated 33.8 per cent of the total foliar nitrogen from the faeces of Hardwicke's woolly bats (Kerivoula hardwickii hardwickii) that exclusively roost in its aerial pitchers. This is the first case in which the faeces-trapping syndrome has been documented in a pitcher plant that attracts bats and only the second case of a mutualistic association between a carnivorous plant and a mammal to date.
Grafe, T. Ulmar; Schöner, Caroline R.; Kerth, Gerald; Junaidi, Anissa; Schöner, Michael G.
Mutualistic relationships between vertebrates and plants apart from the pollen and seed-dispersal syndromes are rare. At first view, carnivorous pitcher plants of the genus Nepenthes seem to be highly unlikely candidates for mutualistic interactions with animals, as they form dimorphic terrestrial and aerial pitchers that trap arthropods and small vertebrates. Surprisingly, however, the aerial pitchers of Nepenthes rafflesiana variety elongata are poor insect traps, with low amounts of insect-attractive volatile compounds and low amounts of digestive fluid. Here, we show that N. rafflesiana elongata gains an estimated 33.8 per cent of the total foliar nitrogen from the faeces of Hardwicke's woolly bats (Kerivoula hardwickii hardwickii) that exclusively roost in its aerial pitchers. This is the first case in which the faeces-trapping syndrome has been documented in a pitcher plant that attracts bats and only the second case of a mutualistic association between a carnivorous plant and a mammal to date. PMID:21270023
Scharmann, Mathias; Thornham, Daniel G.; Grafe, T. Ulmar; Federle, Walter
Many plants combat herbivore and pathogen attack indirectly by attracting predators of their herbivores. Here we describe a novel type of insect–plant interaction where a carnivorous plant uses such an indirect defence to prevent nutrient loss to kleptoparasites. The ant Camponotus schmitzi is an obligate inhabitant of the carnivorous pitcher plant Nepenthes bicalcarata in Borneo. It has recently been suggested that this ant–plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N. bicalcarata host plant leaves naturally have an elevated 15N/14N stable isotope abundance ratio (δ15N) when colonised by C. schmitzi. This indicates that a higher proportion of the plants’ nitrogen is insect-derived when C. schmitzi ants are present (ca. 100%, vs. 77% in uncolonised plants) and that more nitrogen is available to them. We demonstrated direct flux of nutrients from the ants to the host plant in a 15N pulse-chase experiment. As C. schmitzi ants only feed on nectar and pitcher contents of their host, the elevated foliar δ15N cannot be explained by classic ant-feeding (myrmecotrophy) but must originate from a higher efficiency of the pitcher traps. We discovered that C. schmitzi ants not only increase the pitchers' capture efficiency by keeping the pitchers’ trapping surfaces clean, but they also reduce nutrient loss from the pitchers by predating dipteran pitcher inhabitants (infauna). Consequently, nutrients the pitchers would have otherwise lost via emerging flies become available as ant colony waste. The plants’ prey is therefore conserved by the ants. The interaction between C. schmitzi, N. bicalcarata and dipteran pitcher infauna represents a new type of mutualism where animals mitigate the damage by nutrient thieves to a plant. PMID:23717446
Gaume, Laurence; Forterre, Yoel
We study the rheology of the digestive fluid secreted by the carnivorous pitcher plants Nepenthes rafflesiana and its role in the mechanism of insects trapping. Using a combination of physical measurements (surface tension, wetting properties, extensional and shear rheometry), insects bioessays and high-speed video, we show that the digestive fluid of Nepenthes rafflesiana is a highly viscoelastic fluid and that this property is crucial for the retention of insect in its trap. Trapping efficiency is shown to remain strong even when the fluid is highly diluted by water, as long as the elastic relaxation time of the fluid is higher than the typical time scale of insect movements (large Deborah numbers).
McPherson, Sue; MacMahon, Clare
Our understanding of the role of tactical knowledge in baseball batting preparation is scarce, thereby limiting training guidelines. We examined the verbal reports of baseball players and nonplayers when told to view different edited video sequences of a half-inning of baseball competition under different task conditions: to prepare to bat (problem solve); recall as much information as possible (intentional recall); or prepare to bat, with an unexpected recall (incidental recall). Separate mixed-model ANOVAs (Expertise x Instruction conditions) on verbal report measures indicated that nonplayers used general strategies for recalling baseball events and lacked the tactical skills to use such information for their upcoming times at bat. In contrast, players used baseball-specific strategies to encode and retrieve pertinent game events from long-term memory (LTM) to develop tactics for their upcoming times at bat and to recall as much information as possible. Recommendations for training tactical skills are presented as some players exhibited deficiencies in the LTM structures that mediate batting decisions.
Koopman, Margaret M; Fuselier, Danielle M; Hird, Sarah; Carstens, Bryan C
The ability of American carnivorous pitcher plants (Sarracenia) to digest insect prey is facilitated by microbial associations. Knowledge of the details surrounding this interaction has been limited by our capability to characterize bacterial diversity in this system. To describe microbial diversity within and between pitchers of one species, Sarracenia alata, and to explore how these communities change over time as pitchers accumulate and digest insect prey, we collected and analyzed environmental sequence tag (454 pyrosequencing) and genomic fingerprint (automated ribosomal intergenic spacer analysis and terminal restriction fragment length polymorphism) data. Microbial richness associated with pitcher plant fluid is high; more than 1,000 unique phylogroups were identified across at least seven phyla and 50 families. We documented an increase in bacterial diversity and abundance with time and observed repeated changes in bacterial community composition. Pitchers from different plants harbored significantly more similar bacterial communities at a given time point than communities coming from the same genetic host over time. The microbial communities in pitcher plant fluid also differ significantly from those present in the surrounding soil. These findings indicate that the bacteria associated with pitcher plant leaves are far from random assemblages and represent an important step toward understanding this unique plant-microbe interaction.
Takeuchi, Yayoi; Chaffron, Samuel; Salcher, Michaela M; Shimizu-Inatsugi, Rie; Kobayashi, Masaki J; Diway, Bibian; von Mering, Christian; Pernthaler, Jakob; Shimizu, Kentaro K
Pitchers are modified leaves used by carnivorous plants for trapping prey. Their fluids contain digestive enzymes from the plant and they harbor abundant microbes. In this study, the diversity of bacterial communities was assessed in Nepenthes pitcher fluids and the composition of the bacterial community was compared to that in other environments, including the phyllosphere of Arabidopsis, animal guts and another pitcher plant, Sarracenia. Diversity was measured by 454 pyrosequencing of 16S rRNA gene amplicons. A total of 232,823 sequences were obtained after chimera and singleton removal that clustered into 3260 distinct operational taxonomic units (OTUs) (3% dissimilarity), which were taxonomically distributed over 17 phyla, 25 classes, 45 orders, 100 families, and 195 genera. Pyrosequencing and fluorescence in situ hybridization yielded similar estimates of community composition. Most pitchers contained high proportions of unique OTUs, and only 22 OTUs (<0.6%) were shared by ≥14/16 samples, suggesting a unique bacterial assemblage in each pitcher at the OTU level. Diversity analysis at the class level revealed that the bacterial communities of both opened and unopened pitchers were most similar to that of Sarracenia and to that in the phyllosphere. Therefore, the bacterial community in pitchers may be formed by environmental filtering and/or by phyllosphere bacteria.
Jeong, Hyang Min; Kim, Sang-Woo; Choi, Younguk; Kim, Aaram J.; Eun, Jonghyoun; Kim, Beom Jun
We study the so-called traveling tournament problem (TTP) to find an optimal tournament schedule. Differently from the original TTP, in which the total travel distance of all the participants is the objective function to minimize, we instead seek to maximize the fairness of the round robin tournament schedule of the Korean Baseball League. The standard deviation of the travel distances of teams is defined as the energy function, and the Metropolis Monte-Carlo method combined with the simulated annealing technique is applied to find the ground-state configuration. The resulting tournament schedule is found to satisfy all the constraint rules set by the Korean Baseball Organization, but with drastically increased fairness in traveling distances.
Jones, Marshall B
Home advantage is smaller in baseball than in other major professional sports for men, specifically football, basketball, or soccer. This paper advances an explanation. It begins by reviewing the main observations to support the view that there is little or no home advantage in individual sports. It then presents the case that home advantage originates in impaired teamwork among the away players. The need for teamwork and the extent of it vary from sport to sport. To the extent that a sport requires little teamwork it is more like an individual sport, and the home team would be expected to enjoy only a small advantage. Interactions among players on the same side (teamwork) are much less common in baseball than in the other sports considered.
Saint Onge, Jarron M.; Rogers, Richard G.; Krueger, Patrick M.
Objective We examine the importance of anthropometric and performance measures, and age, period, and cohort effects in explaining life expectancies among major league baseball (MLB) players over the past century. Methods We use discrete time hazard models to calculate life tables with covariates with data from Total Baseball, a rich source of information on all players who played in the major league. Results Compared to 20-year-old U.S. males, MLB players can expect almost five additional years of life. Height, weight, handedness, and player ratings are unassociated with the risk of death in this population of highly active and successful adults. Career length is inversely associated with the risk of death, likely because those who play longer gain additional incomes, physical fitness, and training. Conclusions Our results indicate improvements in life expectancies with time for all age groups and indicate possible improvements in longevity in the general U.S. population. PMID:19756205
Reeves, W K
The fungus Smittium culisetae is a trichomycete that develops in the hindguts of larval aquatic Diptera. This is the first report of S. culisetae from the pitcher plant mosquito, Wyeomyia smithii. Larvae of the mosquito were collected from the purple pitcher plant, Sarracenia purpurea, from a bog in Jackson County, North Carolina. The lowest proportions of colonized larvae occurred in December, January and July. The greatest proportions of colonized larvae occurred in October and March. The distribution of colonized larvae among pitchers did not differ significantly from a random distribution.
Crepeau, Richard C.
The history of sports is closely tied to the larger history of the society in which they are played. Baseball in the United States in the 1920's and l930's assumed a major role in spreading the ideals of fair play, sportsmanship, and democracy to the Far East, with tours by amateur athletes and professionals such as Lou Gehrig and Babe Ruth. Even…
Paulino, Franklin E; Villacis, Diego C; Ahmad, Christopher S
Repetitive throwing, such as in baseball pitching, applies massive stress on the elbow. This can often lead to a predictable constellation of elbow injuries, such as valgus extension overload syndrome (VEO). The following review of VEO provides an understanding of relevant anatomy, explanation of pathomechanics, key aspects to clinical evaluation, effective treatment options, and indications for surgery. In addition, we provide the senior author's (CSA) preferred arthroscopic technique for cases of VEO refractory to conservative management.
Baseball and softball bats are sold according to length in inches and weight in ounces. Much to the consternation of players buying new bats, however, not all bats that weigh the same swing the same. The reason for this has to do with moment of inertia of the bat about a pivot point on the handle, or what the sporting goods industry refers to as…
Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan
Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries. PMID:26793294
Sire, C.; Redner, S.
Can one understand the statistics of wins and losses of baseball teams? Are their consecutive-game winning and losing streaks self-reinforcing or can they be described statistically? We apply the Bradley-Terry model, which incorporates the heterogeneity of team strengths in a minimalist way, to answer these questions. Excellent agreement is found between the predictions of the Bradley-Terry model and the rank dependence of the average number team wins and losses in major-league baseball over the past century when the distribution of team strengths is taken to be uniformly distributed over a finite range. Using this uniform strength distribution, we also find very good agreement between model predictions and the observed distribution of consecutive-game team winning and losing streaks over the last half-century; however, the agreement is less good for the previous half-century. The behavior of the last half-century supports the hypothesis that long streaks are primarily statistical in origin with little self-reinforcing component. The data further show that the past half-century of baseball has been more competitive than the preceding half-century.
This study used signal detection theory to conceptualize the problem a baseball batter faces when deciding whether or not to swing at a pitch. It examined the launch angle (LA) criteria used by expert (college players) and less experienced (recreational league players) batters using a baseball batting simulation. This study showed that, although…
Levine, Martin G.
A bilingual baseball dictionary was designed for intermediate and advanced level students of Spanish or English who want to read about baseball games in the newspapers or follow the coverage on the radio or television. The dictionary includes enough vocabulary to help the fan enjoy the game from the perspective of another language and culture. The…
Beginning in 1897, American Indians endured their own integration experience in professional baseball. The experience was propelled by government boarding schools, which used baseball as a tool for assimilation and for prestige and profit. But the players on boarding-school teams often found in the sport their own means of cultural resistance and…
Surendra, Nanda C.; Denton, James W.
Baseball's "Moneyball" theory states that the baseball market undervalues some attributes (and players with these attributes) that are key contributors to wins while overvaluing other attributes. Teams who correctly evaluate attributes that contribute to wins have higher winning percentages with relatively low payrolls. We applied the Moneyball…
The bilingual glossary, in both English-to-Spanish and Spanish-to-English, defines words and phrases related to the game of baseball as it is reported by Spanish-language newspapers and magazines in Mexico and the United States. A list of U.S. and Mexican baseball league teams is appended. (MSE)
Mills, Brett D.
This paper reviews the literature on women's baseball prior to the establishment of the All-American Girls Professional Baseball League by P. K. Wrigley in 1943. Around the turn of the century, women had fewer opportunities for participation in sports and long standing stereotypes permeated the thoughts and ideals of society with respect to women…
Vernon, John, Ed.
Discusses the history of baseball cards and their use in the classroom as historical documents. Includes five exercises which deal with trading cards and the game itself. Provides a blown-up version of a 1950's Minnie Minoso baseball card to be used with one of the exercises. (GEA)
Lund, Robin J.; Heefner, Dan
Former baseball star Jim Lefebvre (1983) claimed that hitting a baseball may be the most talked about but least understood skill in all of sports. Historically, hitting instruction has been based on intuitive thinking by "hitting gurus," rather than on scientific fact, which has contributed to this lack of understanding (DeRenne, Stellar, &…
Yen, K L; Metzl, J D
The sport of baseball is played by millions of children across America and around the world. Although generally considered a safe activity, it is estimated that there are over 100,000 acute baseball injuries yearly in the 5- to 14-year age range in the United States, many of which present to the emergency department. Acute injuries often involve ball impact to the face and hands; baseball is the leading cause of sport-related eye injury. Ball impact particularly to the chest results in a small but steady number of fatalities each year, many of which are widely publicized events. In addition to acute injury, many young baseball players are affected by chronic and acute conditions of the elbow. In this article, we review the history, epidemiology, and common injury patterns that are specific to baseball. Case reports are included, as well as a section on the physical examination of the elbow.
Nakata, Hiroki; Nagami, Tomoyuki; Higuchi, Takatoshi; Sakamoto, Kiwako; Kanosue, Kazuyuki
The present study investigated the relationship of performance variables and anthropometric measurements on baseball ability in 164 youth baseball players (age: 6.4-15.7 years). To evaluate their baseball performance, ball speeds in pitching and batting were recorded and kinetic energies of the pitched and hit balls were calculated. To record anthropometric and physical fitness characteristics, height and weight were measured and a battery of physical fitness tests covering standing long jump, side steps, sit-ups, 10-m sprint, trunk flexion, back strength, and grip strengths of both hands were conducted. The results of a multiple regression analysis revealed several significant predictors: age, body mass index (BMI), standing long jump, 10-m sprint, and grip strength for pitched ball kinetic energy and age, BMI, standing long jump, and back strength for hit ball kinetic energy. This study provides scientific evidence that relates certain specific physical performance tests and body characteristics with high achievement in the actual performance of pitching and batting. Youth players, their parents, coaches, and trainers would benefit by addressing these characteristics when planning training programs to improve the baseball performance of youth players.
Clarke, Charles M.; Bauer, Ulrike; Lee, Ch'ien C.; Tuen, Andrew A.; Rembold, Katja; Moran, Jonathan A.
Nepenthes pitcher plants are typically carnivorous, producing pitchers with varying combinations of epicuticular wax crystals, viscoelastic fluids and slippery peristomes to trap arthropod prey, especially ants. However, ant densities are low in tropical montane habitats, thereby limiting the potential benefits of the carnivorous syndrome. Nepenthes lowii, a montane species from Borneo, produces two types of pitchers that differ greatly in form and function. Pitchers produced by immature plants conform to the ‘typical’ Nepenthes pattern, catching arthropod prey. However, pitchers produced by mature N. lowii plants lack the features associated with carnivory and are instead visited by tree shrews, which defaecate into them after feeding on exudates that accumulate on the pitcher lid. We tested the hypothesis that tree shrew faeces represent a significant nitrogen (N) source for N. lowii, finding that it accounts for between 57 and 100 per cent of foliar N in mature N. lowii plants. Thus, N. lowii employs a diversified N sequestration strategy, gaining access to a N source that is not available to sympatric congeners. The interaction between N. lowii and tree shrews appears to be a mutualism based on the exchange of food sources that are scarce in their montane habitat. PMID:19515656
Clarke, Charles M; Bauer, Ulrike; Lee, Ch'ien C; Tuen, Andrew A; Rembold, Katja; Moran, Jonathan A
Nepenthes pitcher plants are typically carnivorous, producing pitchers with varying combinations of epicuticular wax crystals, viscoelastic fluids and slippery peristomes to trap arthropod prey, especially ants. However, ant densities are low in tropical montane habitats, thereby limiting the potential benefits of the carnivorous syndrome. Nepenthes lowii, a montane species from Borneo, produces two types of pitchers that differ greatly in form and function. Pitchers produced by immature plants conform to the 'typical' Nepenthes pattern, catching arthropod prey. However, pitchers produced by mature N. lowii plants lack the features associated with carnivory and are instead visited by tree shrews, which defaecate into them after feeding on exudates that accumulate on the pitcher lid. We tested the hypothesis that tree shrew faeces represent a significant nitrogen (N) source for N. lowii, finding that it accounts for between 57 and 100 per cent of foliar N in mature N. lowii plants. Thus, N. lowii employs a diversified N sequestration strategy, gaining access to a N source that is not available to sympatric congeners. The interaction between N. lowii and tree shrews appears to be a mutualism based on the exchange of food sources that are scarce in their montane habitat.
Bauer, Ulrike; Bohn, Holger F; Federle, Walter
The leaves of Nepenthes pitcher plants are specialized pitfall traps which capture and digest arthropod prey. In many species, insects become trapped by ‘aquaplaning’ on the wet pitcher rim (peristome). Here we investigate the ecological implications of this capture mechanism in Nepenthes rafflesiana var. typica. We combine meteorological data and continuous field measurements of peristome wetness using electrical conductance with experimental assessments of the pitchers' capture efficiency. Our results demonstrate that pitchers can be highly effective traps with capture rates as high as 80% but completely ineffective at other times. These dramatic changes are due to the wetting condition of the peristome. Variation of peristome wetness and capture efficiency was perfectly synchronous, and caused by rain, condensation and nectar secreted from peristome nectaries. The presence of nectar on the peristome increased surface wetness mainly indirectly by its hygroscopic properties. Experiments confirmed that pitchers with removed peristome nectaries remained generally drier and captured prey less efficiently than untreated controls. This role of nectar in prey capture represents a novel function of plant nectar. We propose that the intermittent and unpredictable activation of Nepenthes pitcher traps facilitates ant recruitment and constitutes a strategy to maximize prey capture. PMID:18048280
Didham, Raphael K.; Hopper, Stephen D.
Carnivorous plants allocate more resources to carnivorous structures under nutrient-limited conditions, and relative investment can also be influenced by animals (infauna) that live in association with these plants and feed on their prey. We investigated these effects within a population of the pitcher plant Cephalotus follicularis containing varying densities of larvae of the fly Badisis ambulans. For plants with a relatively high proportion of adult pitchers, increasing larval density was associated with lower relative leaf allocation to new pitcher buds. For plants with relatively few adult pitchers, however, there was greater relative leaf allocation to pitcher buds with increasing larval density. In a field experiment, there was no significant effect of experimental larval presence or absence on the change in carbon-to-nitrogen (C/N) ratio of plants. Although the direction of the correlation between B. ambulans larvae and relative investment in carnivorous and non-carnivorous structures depends on the relative number of mature structures, whether the larvae enhance or reduce nutrient stress under different conditions remains unclear. The change in C/N was, however, less variable for pitchers that contained larvae, suggesting a stabilizing effect. Eighteen of 52 experimental pitchers were damaged by an unknown species, causing the pitcher fluid to drain. These pitchers were significantly more likely to survive if they contained larvae. These results suggest that the relationship between infauna and host varies with the initial resource status and environmental context of the host plant. PMID:28018659
Lymbery, Samuel J; Didham, Raphael K; Hopper, Stephen D; Simmons, Leigh W
Carnivorous plants allocate more resources to carnivorous structures under nutrient-limited conditions, and relative investment can also be influenced by animals (infauna) that live in association with these plants and feed on their prey. We investigated these effects within a population of the pitcher plant Cephalotus follicularis containing varying densities of larvae of the fly Badisis ambulans. For plants with a relatively high proportion of adult pitchers, increasing larval density was associated with lower relative leaf allocation to new pitcher buds. For plants with relatively few adult pitchers, however, there was greater relative leaf allocation to pitcher buds with increasing larval density. In a field experiment, there was no significant effect of experimental larval presence or absence on the change in carbon-to-nitrogen (C/N) ratio of plants. Although the direction of the correlation between B. ambulans larvae and relative investment in carnivorous and non-carnivorous structures depends on the relative number of mature structures, whether the larvae enhance or reduce nutrient stress under different conditions remains unclear. The change in C/N was, however, less variable for pitchers that contained larvae, suggesting a stabilizing effect. Eighteen of 52 experimental pitchers were damaged by an unknown species, causing the pitcher fluid to drain. These pitchers were significantly more likely to survive if they contained larvae. These results suggest that the relationship between infauna and host varies with the initial resource status and environmental context of the host plant.
Freeston, Jonathan; Rooney, Kieron
Throwing speed and accuracy are both critical to sports performance but cannot be optimized simultaneously. This speed-accuracy trade-off (SATO) is evident across a number of throwing groups but remains poorly understood. The goal was to describe the SATO in baseball and cricket players and determine the speed that optimizes accuracy. 20 grade-level baseball and cricket players performed 10 throws at 80% and 100% of maximal throwing speed (MTS) toward a cricket stump. Baseball players then performed a further 10 throws at 70%, 80%, 90%, and 100% of MTS toward a circular target. Baseball players threw faster with greater accuracy than cricket players at both speeds. Both groups demonstrated a significant SATO as vertical error increased with increases in speed; the trade-off was worse for cricketers than baseball players. Accuracy was optimized at 70% of MTS for baseballers. Throwing athletes should decrease speed when accuracy is critical. Cricket players could adopt baseball-training practices to improve throwing performance.
Pinkowsky, Gregory J.; Roberts, John; Allred, Jeff; Pujalte, George G.; Gallo, Robert A.
Thenar pain can represent a significant morbidity for a baseball player who relies on manual dexterity for gripping a bat and precise and accurate throws. While osseous, ligamentous, and neurovascular pathologies are commonly considered, musculotendinous injuries are often neglected in the differential diagnosis of thenar pain. We present a case of adductor pollicis longus strain as a cause of acute thenar pain in a baseball player. Adductor pollicis longus strains should be considered in any baseball player sustaining a hyperabduction force to the thumb. PMID:24459545
Schulze, W; Frommer, W B; Ward, J M
Insect capture and digestion contribute substantially to the nitrogen budget of carnivorous plants. In Nepenthes, insect-derived nitrogenous compounds are imported from the pitcher fluid and transported throughout the plant via the vascular tissue to support growth. Import and distribution of nutrients may require transmembrane nitrogen transporters. Representatives of three classes of genes encoding transporters for the nitrogenous compounds ammonium, amino acids and peptides were identified in Nepenthes pitchers. The expression at the cellular level of an ammonium transporter gene, three amino acid transporter genes, and one peptide transporter gene were investigated in the insect trapping organs of Nepenthes. Expression of the ammonium transporter gene NaAMT1 was detected in the head cells of digestive glands in the lower part of the pitcher where NaAMT1 may function in ammonium uptake from the pitcher fluid. One amino acid transporter gene, NaAAP1, was expressed in bundle sheath cells surrounding the vascular tissue. To understand the locations where transmembrane transport could be required within the pitcher, symplasmic and apoplasmic continuity was probed using fluorescent dyes. Symplasmic connections were not found between cortical cells and vascular bundles. Therefore, the amino acid transporter encoded by NaAAP1 may be involved in transport of amino acids into the vascular tissue. In contrast, expression of the peptide transporter gene NaNTR1 was detected in phloem cells of the vascular tissue within pitchers. NaNTR1 may function in the export of nitrogen from the pitcher by loading peptides into the phloem.
Giusto, Bruno Di; Grosbois, Vladimir; Fargeas, Elodie; Marshall, David J; Gaume, Laurence
Mechanisms that improve prey richness in carnivorous plants may involve three crucial phases of trapping:attraction, capture and retention. Nepenthes rafflesiana var. typica is an insectivorous pitcher plant that is widespread in northern Borneo. It exhibits ontogenetic pitcher dimorphism with the upper pitchers trapping more flying prey than the lower pitchers. While this difference in prey composition has been ascribed to differences in attraction,the contribution of capture and retention has been overlooked. This study focused on distinguishing between the prey trapping mechanisms, and assessing their relative contribution to prey diversity. Arthropod richness and diversity of both visitors and prey in the two types of pitchers were analysed to quantify the relative contribution of attraction to prey trapping. Rate of insect visits to the different pitcher parts and the presence or absence of a sweet fragrance was recorded to clarify the origin and mechanism of attraction. The mechanism of retention was studied by insect bioassays and measurements of fluid viscosity. Nepenthes rafflesiana was found to trap a broader prey spectrum than that previously described for any Nepenthes species,with the upper pitchers attracting and trapping a greater quantity and diversity of prey items than the lower pitchers. Capture efficiency was low compared with attraction or retention efficiency. Fragrance of the peristome,or nectar rim,accounted mainly for the observed non-specific, better prey attraction by the upper pitchers, while the retentive properties of the viscous fluid in these upper pitchers arguably explains the species richness of their flying prey. The pitchers of N. rafflesiana are therefore more than simple pitfall traps and the digestive fluid plays an important yet unsuspected role in the ecological success of the species.
Oliver, Gretchen; Weimar, Wendi
Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players. Twenty-five youth baseball players (age 11.3 + 1.0 years; body height 152.4 + 9.0 cm; body mass 47.5 + 11.3 kg), with no history of injury, participated in the study. Scapular kinematics at the events of maximum humeral external rotation (MER) and maximum humeral internal rotation (MIR) during the pitching motion were assessed three-dimensionally while pitching fastballs for strikes. Results revealed that at the event of MER, the scapula was in a position of retraction, upward rotation and a posterior tilt. While at the event of MIR, the scapula was protracted, upward rotated and tilted anteriorly. PMID:26839605
The sports world is in an uproar over performance-enhancing drugs. In the United States steroids in baseball have received the most attention, in part because the purported effects are much more dramatic than in any other sport. From 1995-2003 a few players hit home runs at rates 20-50% higher than the best sluggers of the preceding century. Could steroids really increase home-run performance that much? I will describe a model that combines estimates of the physiological effects of steroids, known baseball physics, and reasonable models of batting effectiveness for highly skilled hitters. A 10% increase in muscle mass, which can reasonably be expected from steroid use, increases the speed of a batted ball by 3%. Because home runs are relatively rare events on the tail of a batter's range distribution, even this modest change in ball speed can increase the proportion of batted balls that result in home runs by 30 -- 70%, enough to account for the record-shattering performances of the recent past. I will also describe some of the attention -- both welcome and not -- that comes to the unsuspecting physicist who wades into such emotionally troubled waters.
Oliver, Gretchen; Weimar, Wendi
Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players. Twenty-five youth baseball players (age 11.3 + 1.0 years; body height 152.4 + 9.0 cm; body mass 47.5 + 11.3 kg), with no history of injury, participated in the study. Scapular kinematics at the events of maximum humeral external rotation (MER) and maximum humeral internal rotation (MIR) during the pitching motion were assessed three-dimensionally while pitching fastballs for strikes. Results revealed that at the event of MER, the scapula was in a position of retraction, upward rotation and a posterior tilt. While at the event of MIR, the scapula was protracted, upward rotated and tilted anteriorly.
2. Missile Alert Facility, south side, view from baseball bleachers. Lyon - Whiteman Air Force Base, Oscar O-1 Minuteman Missile Alert Facility, Southeast corner of Twelfth & Vendenberg Avenues, Knob Noster, Johnson County, MO
Nakamura, Takao; Kusuhara, Toshimasa; Yamamoto, Yoshitake
The extroversion or hyperextension of elbow joint cause disorders of elbow joint in throwing a baseball. A method, which is easy handling and to measure motion objectively, can be useful for evaluation of throwing motion. We investigated a possibility of motion discrimination of throwing a baseball using electrical impedance method. The parameters of frequency characteristics (Cole-Cole arc) of forearm electrical impedance were measured during four types of throwing a baseball. Multiple discriminant analysis was used and the independent variables were change ratios of 11 parameters of forearm electrical impedance. As results of 120 data with four types of throwing motion in three subjects, hitting ratio was very high and 95.8%. We can expect to discriminate throwing a baseball using multiple discriminant analysis of impedance parameters.
Chin, Lijin; Moran, Jonathan A; Clarke, Charles
*Three Bornean pitcher plant species, Nepenthes lowii, N. rajah and N. macrophylla, produce modified pitchers that 'capture' tree shrew faeces for nutritional benefit. Tree shrews (Tupaia montana) feed on exudates produced by glands on the inner surfaces of the pitcher lids and defecate into the pitchers. *Here, we tested the hypothesis that pitcher geometry in these species is related to tree shrew body size by comparing the pitcher characteristics with those of five other 'typical' (arthropod-trapping) Nepenthes species. *We found that only pitchers with large orifices and lids that are concave, elongated and oriented approximately at right angles to the orifice capture faeces. The distance from the tree shrews' food source (that is, the lid nectar glands) to the front of the pitcher orifice precisely matches the head plus body length of T. montana in the faeces-trapping species, and is a function of orifice size and the angle of lid reflexion. *Substantial changes to nutrient acquisition strategies in carnivorous plants may occur through simple modifications to trap geometry. This extraordinary plant-animal interaction adds to a growing body of evidence that Nepenthes represents a candidate model for adaptive radiation with regard to nitrogen sequestration strategies.
Beyer, Jeffrey A; Rowson, Steven; Duma, Stefan M
Some reports have shown that head injuries in baseball may comprise up to 18.5% of all competitive sports-related head injuries. The objective of this study was to evaluate the response of catcher and umpire masks to impacts at these different regions to discover the impact conditions that represent the greatest risk of injury. A series of 10 events in which a catcher or umpire in Major League Baseball, who experienced a foul ball to the mask that resulted in a concussion, were analyzed through video and data on pitch characteristics. It was found that the impacts were distributed across the face, and the median plate speed was approximately 38 m/s (84 mph). To determine the relative severity of each identified impact location, an instrumented Hybrid III head outfitted with a catcher or umpire mask was impacted with baseballs. Testing at 27 and 38 m/s (60 and 84 mph) suggested that impacts to the center-eyebrow and chin locations were the most severe. Peak linear and rotational accelerations were found to be lower than the suggested injury thresholds. While impacts to a mask result in head accelerations which are near or below levels commonly associated with the lower limits for head injury, the exact injury mechanism is unclear, as concussions are still experienced by the mask wearers.
Adlassnig, Wolfram; Steinhauser, Georg; Peroutka, Marianne; Musilek, Andreas; Sterba, Johannes H; Lichtscheidl, Irene K; Bichler, Max
Carnivorous plants use animals as fertiliser substitutes which allow them to survive on nutrient deficient soils. Most research concentrated on the uptake of the prey's nitrogen and phosphorus; only little is known on the utilisation of other elements. We studied the uptake of three essential nutrients, potassium, iron and manganese, in three species of carnivorous pitcher plants (Cephalotus follicularis LaBilladiere, Sarracenia purpureaL., Heliamphora nutans Bentham). Using relatively short-lived and gamma-emitting radiotracers, we significantly improved the sensitivity compared to conventional protocols and gained the following results. We demonstrated the uptake of trace elements like iron and manganese. In addition, we found direct evidence for the uptake of potassium into the pitcher tissue. Potassium and manganese were absorbed to virtually 100% if offered in physiological concentrations or below in Cephalotus. Analysis of pitcher fluid collected in the natural habitat showed that uptake was performed here as efficiently as in the laboratory. The absorption of nutrients is an active process depending on living glandular cells in the pitcher epidermis and can be inhibited by azide. Unphysiologically high amounts of nutrients were taken up for a short time, but after a few hours the absorbing cells were damaged, and uptake stopped. Absorption rates of pitcher leaves from plants under controlled conditions varied highly, indicating that each trap is functionally independent. The comparison of minerals in typical prey with the plants' tissues showed that a complete coverage of the plants' needs by prey capture is improbable.
Clarke, Charles; Moran, Jonathan A; Chin, Lijin
Three species of Nepenthes pitcher plants from Borneo engage in a mutualistic interaction with mountain tree shrews, the basis of which is the exchange of nutritional resources. The plants produce modified "toilet pitchers" that produce copious amounts of exudates, the latter serving as a food source for tree shrews. The exudates are only accessible to the tree shrews when they position their hindquarters over the pitcher orifice. Tree shrews mark valuable resources with faeces and regularly defecate into the pitchers when they visit them to feed. Faeces represent a valuable source of nitrogen for these Nepenthes species, but there are many facets of the mutualism that are yet to be investigated. These include, but are not limited to, seasonal variation in exudate production rates by the plants, behavioral ecology of visiting tree shrews, and the mechanism by which the plants signal to tree shrews that their pitchers represent a food source. Further research into this extraordinary animal-plant interaction is required to gain a better understanding of the benefits to the participating species.
Alaways, L W; Hubbard, M
The aim of this study was to develop a new method for the determination of lift on spinning baseballs. Inertial trajectories of (a) ball surface markers during the first metre of flight and (b) the centre of mass trajectory near home-plate were measured in a pitch using high-speed video. A theoretical model was developed, incorporating aerodynamic Magnus-Robins lift, drag and cross forces, which predicts the centre of mass and marker trajectories. Parameters including initial conditions and aerodynamic coefficients were estimated iteratively by minimizing the error between predicted and measured trajectories. We compare the resulting lift coefficients and spin parameter values with those of previous studies. Lift on four-seam pitches can be as much as three times that of two-seam pitches, although this disparity is reduced for spin parameters greater than 0.4.
Bauer, Ulrike; Clemente, C J; Renner, T; Federle, W
Carnivorous plants of the genus Nepenthes have evolved a striking diversity of pitcher traps that rely on specialized slippery surfaces for prey capture. With a comparative study of trap morphology, we show that Nepenthes pitcher plants have evolved specific adaptations for the use of either one of two distinct trapping mechanisms: slippery wax crystals on the inner pitcher wall and 'insect aquaplaning' on the wet upper rim (peristome). Species without wax crystals had wider peristomes with a longer inward slope. Ancestral state reconstructions identified wax crystal layers and narrow, symmetrical peristomes as ancestral, indicating that wax crystals have been reduced or lost multiple times independently. Our results complement recent reports of nutrient source specializations in Nepenthes and suggest that these specializations may have driven speciation and rapid diversification in this genus.
Bauer, Ulrike; Scharmann, Mathias; Skepper, Jeremy; Federle, Walter
Trichomes are a common feature of plants and perform important and diverse functions. Here, we show that the inward-pointing hairs on the inner wall of insect-trapping Heliamphora nutans pitchers are highly wettable, causing water droplets to spread rapidly across the surface. Wetting strongly enhanced the slipperiness and increased the capture rate for ants from 29 to 88 per cent. Force measurements and tarsal ablation experiments revealed that wetting affected the insects' adhesive pads but not the claws, similar to the 'aquaplaning' mechanism of (unrelated) Asian Nepenthes pitcher plants. The inward-pointing trichomes provided much higher traction when insects were pulled outwards. The wetness-dependent capture mechanisms of H. nutans and Nepenthes pitchers present a striking case of functional convergence, whereas the use of wettable trichomes constitutes a previously unknown mechanism to make plant surfaces slippery.
Rasic, Gordana; Keyghobadi, Nusha
We investigated the pattern of spatial genetic structure and the extent of gene flow in the pitcher plant flesh fly Fletcherimyia fletcheri, the largest member of the inquiline community of the purple pitcher plant Sarracenia purpurea. Using microsatellite loci, we tested the theoretical predictions of different hypothesized population models (patchy population, metapopulation, or isolated populations) among 11 bogs in Algonquin Provincial Park (Canada). Our results revealed that the pitcher plant flesh fly exhibits a mixture of patchy and metapopulation characteristics. There is significant differentiation among bogs and limited gene flow at larger spatial scales, but local populations do not experience frequent local extinctions/recolonizations. Our findings suggest a strong dispersal ability and stable population sizes in F. fletcheri, providing novel insights into the ecology of this member of a unique ecological microcosm.
Moran, Jonathan A; Clarke, Charles M
Nepenthes is the largest genus of pitcher plants, with its centre of diversity in SE Asia. The plants grow in substrates that are deficient in N and offset this deficiency by trapping animal prey, primarily arthropods. Recent research has provided new insights into the function of the pitchers, particularly with regard to prey tapping and retention. Species examined to date use combinations of wettable peristomes, wax layers and viscoelastic fluid to trap and retain prey. In many respects, this has redefined our understanding of the functioning of Nepenthes pitchers. In addition, recent research has shown that several Nepenthes species target specific groups of prey animals, or are even evolving away from a strictly carnivorous mode of operation. Future research into nutrient sequestration strategies and mechanisms of prey attraction would no doubt further enhance our knowledge of the ecology of this remarkable genus.
Wight, Jeff; Richards, James; Hall, Susan
Efficient, sequential timing is essential for upper level pitching. Interestingly, pitchers vary considerably in timing related elements of pitching style including pelvis rotation, arm cocking, stride leg behaviour, and pitch delivery time. The purpose of this study was to determine whether relationships exist among these elements by examining the overall style of pitchers exhibiting different pelvis rotation patterns. Pitching styles were defined by pelvis orientation at the instant of stride foot contact. Pitchers demonstrating a pelvis orientation greater than 30 degrees were designated as 'early rotators', while pitchers demonstrating a pelvis orientation less than 30 degrees were designated as 'late rotators'. Kinematic and temporal differences were associated with the two styles. During the arm cocking phase, early rotators showed significantly greater shoulder external rotation at the instant of stride foot contact, earlier occurrence of maximum pelvis rotation angular velocity, and shorter time taken to complete the phase. However, by the instant of maximum shoulder external rotation, early and late rotators appeared remarkably similar as no significant difference occurred in pelvis and arm orientations. Therefore, it appears that early and late rotators used different methods to achieve similar results, including throwing velocity. Significant differences in throwing arm kinetics were also found for 10 of the 11 measures in the study. As the pelvis assumed a more open position at stride foot contact, maximum kinetic values were found to both decrease in magnitude and occur at an earlier time within the pitch.
Provides discussion questions, activity suggestions and sample quotes to provoke further examination of the Cold War era values evidenced in the baseball subculture (see SO 515 377, "Baseball and the Cold War: An Examination of Values). (JDH)
Rogers, Willie L; Cruse-Sanders, Jennifer M; Determann, Ron; Malmberg, Russell L
Sarracenia species (pitcher plants) are carnivorous plants which obtain a portion of their nutrients from insects captured in the pitchers. Sarracenia species naturally hybridize with each other, and hybrid swarms have been identified. A number of the taxa within the genus are considered endangered. In order to facilitate evolutionary, ecological and conservation genetic analyses within the genus, we developed 25 microsatellite loci which show variability either within species or between species. Three S. purpurea populations were examined with 10 primer sets which showed within population variability.
Rasic, Gordana; Maxwell, Sheri A; Keyghobadi, Nusha
As a component of the inquiline community of the purple pitcher plant (Sarracenia purpurea), the pitcher plant midge Metriocneus knabi has been the subject of various ecological studies. However, very little is known about its characteristics beyond the larval stage, in particular the dispersal ability of adults. This study presents new molecular tools developed for testing of evolutionary and ecological questions in natural populations of this species. We describe a set of 12 microsatellite loci specific to M. knabi that are sufficiently polymorphic to provide insight into population genetic structure and dispersal patterns.
Pappas, A M; Zawacki, R M; Sullivan, T J
Fifteen professional major league pitchers were filmed with high speed cinematography. One hundred forty-seven pitches were analyzed using an electromagnetic digitizer and a microcomputer. Three phases of throwing were studied: cocking, acceleration, and follow-through. The cocking phase is the period of time between the initiation of the windup and the moment at which the shoulder is in maximum external rotation. This phase occurs in approximately 1500 ms, and the shoulder is brought into an extreme position of external rotation. The acceleration phase and the initial stages of the follow-through phase produce extraordinary demands on the shoulder and elbow. The acceleration phase begins with the throwing shoulder in the position of maximum external rotation and terminates with ball release. This phase occurs in approximately 50 ms, and peak angular velocities averaging 6,180 deg/sec for shoulder internal rotation and 4,595 deg/sec for elbow extension were measured. The follow-through phase begins at ball release and continues until the motion of throwing has ceased. This phase occurs in approximately 350 ms.
Nathan, Alan M.; Smith, Lloyd V.; Faber, Warren L.; Russell, Daniel A.
Three questions of relevance to Major League Baseball are investigated from a physics perspective. Can a baseball be hit farther with a corked bat? Is there evidence that the baseball is more lively today than in earlier years? Can storing baseballs in a temperature- or humidity-controlled environment significantly affect home run production? These questions are subjected to a physics analysis, including an experiment and an interpretation of the data. The answers to the three questions are no, no, and yes, respectively.
French, Karen E.; Spurgeon, John H.; Nevett, Michael E.
The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight…
... United States Mint United States Mint Kids' Baseball Coin Design Challenge ACTION: Notification of the Opening of the United States Mint Kids' Baseball Coin Design Challenge on April 11, 2013. SUMMARY: The United States Mint announces the opening of a national kids' baseball coin design challenge on April...
Walker, Donald E.; Cooper, B. Lee
Illustrates the use of baseball cards as cultural artifacts and how to make sociological inferences and historical generalizations from them. Focuses on Black players and the issue of racial integration in major league baseball. Includes chronologies of racial integration on teams and inductions of Black players into the Baseball Hall of Fame. (NL)
Bjarkman, Peter C.
Reviews the participation of various ethnic groups in baseball, and suggests that librarians and teachers can explore the richness and diversity of the American immigrant experience through the growing world of baseball nonfiction. The high-interest material of baseball literature portrays the vibrant and evolving American society. (SLD)
Hatano, Naoya; Hamada, Tatsuro
The Nepenthes species are carnivorous plants that have evolved a specialized leaf organ, the 'pitcher', to attract, capture, and digest insects. The digested insects provide nutrients for growth, allowing these plants to grow even in poor soil. Several proteins have been identified in the pitcher fluid, including aspartic proteases (nepenthesin I and II) and pathogenesis-related (PR) proteins (β-1,3-glucanase, class IV chitinase, and thaumatin-like protein). In this study, we collected and concentrated pitcher fluid to identify minor proteins. In addition, we tried to identify the protein secreted in response to trapping the insect. To make a similar situation in which the insect falls into the pitcher, chitin which was a major component of the insect exoskeleton was added to the fluid in the pitcher. Three PR proteins, class III peroxidase (Prx), β-1,3-glucanase, and class III chitinase, were newly identified. Prx was induced after the addition of chitin to the pitcher fluid. Proteins in the pitcher fluid of the carnivorous plant Nepenthes alata probably have two roles in nutrient supply: digestion of prey and the antibacterial effect. These results suggest that the system for digesting prey has evolved from the defense system against pathogens in the carnivorous plant Nepenthes.
Kang, Kyoung Doo; Hannon, James C.; Hall, Morgan S.; Choi, Jae Won
Objective In this five-year cohort study, we hypothesize that factors of temperament and character in professional baseball players predict the speed of obtaining success and the quality of success as well as anxiety control. Methods Participants included 120 male rookie players from the Korea Baseball Organization (KBO) and 107 male non-players with no history of playing baseball. The personality/characters and state/trait anxieties of participants were assessed with the Temperament and Character Inventory (TCI) and Spielberg's State-Trait Anxiety Inventory-Y (STAI-Y). Over the duration of five years, all the players were subsequently classified into either a success group (major leaguers) or a non-success group (non-major leaguers), depending on their status in the professional baseball league in Korea. Results The players in the group of starters had higher novelty seeking (NS) scores than those of non-starters. The reward dependence (RD) scores of the success group were higher than those of the non-success group. The state anxiety scores in the starter group were negatively correlated with NS scores. The state and trait anxieties in the non-success group were positively correlated with RD scores. Conclusion The results of this study suggest that predictive temperamental factors for success in baseball players include traits of novelty seeking and reward dependence. PMID:26508956
Lee, Linda; Zhang, Ye; Ozar, Brittany; Sensen, Christoph W; Schriemer, David C
Plants belonging to the genus Nepenthes are carnivorous, using specialized pitfall traps called "pitchers" that attract, capture, and digest insects as a primary source of nutrients. We have used RNA sequencing to generate a cDNA library from the Nepenthes pitchers and applied it to mass spectrometry-based identification of the enzymes secreted into the pitcher fluid using a nonspecific digestion strategy superior to trypsin in this application. This first complete catalog of the pitcher fluid subproteome includes enzymes across a variety of functional classes. The most abundant proteins present in the secreted fluid are proteases, nucleases, peroxidases, chitinases, a phosphatase, and a glucanase. Nitrogen recovery involves a particularly rich complement of proteases. In addition to the two expected aspartic proteases, we discovered three novel nepenthensins, two prolyl endopeptidases that we name neprosins, and a putative serine carboxypeptidase. Additional proteins identified are relevant to pathogen-defense and secretion mechanisms. The full complement of acid-stable enzymes discovered in this study suggests that carnivory in the genus Nepenthes can be sustained by plant-based mechanisms alone and does not absolutely require bacterial symbiosis.
Scholz, I; Bückins, M; Dolge, L; Erlinghagen, T; Weth, A; Hischen, F; Mayer, J; Hoffmann, S; Riederer, M; Riedel, M; Baumgartner, W
Pitcher plants of the genus Nepenthes efficiently trap and retain insect prey in highly specialized leaves. Besides a slippery peristome which inhibits adhesion of insects they employ epicuticular wax crystals on the inner walls of the conductive zone of the pitchers to hamper insect attachment by adhesive devices. It has been proposed that the detachment of individual crystals and the resulting contamination of adhesive organs is responsible for capturing insects. However, our results provide evidence in favour of a different mechanism, mainly based on the stability and the roughness of the waxy surface. First, we were unable to detect a large quantity of crystal fragments on the pads of insects detached from mature pitcher surfaces of Nepenthes alata. Second, investigation of the pitcher surface by focused ion beam treatment showed that the wax crystals form a compact 3D structure. Third, atomic force microscopy of the platelet-shaped crystals revealed that the crystals are mechanically stable, rendering crystal detachment by insect pads unlikely. Fourth, the surface profile parameters of the wax layer showed striking similarities to those of polishing paper with low grain size. By measuring friction forces of insects on this artificial surface we demonstrate that microscopic roughness alone is sufficient to minimize insect attachment. A theoretical model shows that surface roughness within a certain length scale will prevent adhesion by being too rough for adhesive pads but not rough enough for claws.
Satler, Jordan D; Zellmer, Amanda J; Carstens, Bryan C
Understanding if the members of an ecological community have co-diversified is a central concern of evolutionary biology, as co-diversification suggests prolonged association and possible coevolution. By sampling associated species from an ecosystem, researchers can better understand how abiotic and biotic factors influence diversification in a region. In particular, studies of co-distributed species that interact ecologically can allow us to disentangle the effect of how historical processes have helped shape community level structure and interactions. Here we investigate the Sarracenia alata pitcher plant system, an ecological community where many species from disparate taxonomic groups live inside the fluid-filled pitcher leaves. Direct sequencing of the eukaryotes present in the pitcher plant fluid enables us to better understand how a host plant can shape and contribute to the genetic structure of its associated inquilines, and to ask whether genetic variation in the taxa are structured in a similar manner to the host plant. We used 454 amplicon-based metagenomics to demonstrate that the pattern of genetic diversity in many, but not all, of the eukaryotic community is similar to that of S. alata, providing evidence that associated eukaryotes share an evolutionary history with the host pitcher plant. Our work provides further evidence that a host plant can influence the evolution of its associated commensals.
Satler, Jordan D.; Zellmer, Amanda J.
Understanding if the members of an ecological community have co-diversified is a central concern of evolutionary biology, as co-diversification suggests prolonged association and possible coevolution. By sampling associated species from an ecosystem, researchers can better understand how abiotic and biotic factors influence diversification in a region. In particular, studies of co-distributed species that interact ecologically can allow us to disentangle the effect of how historical processes have helped shape community level structure and interactions. Here we investigate the Sarracenia alata pitcher plant system, an ecological community where many species from disparate taxonomic groups live inside the fluid-filled pitcher leaves. Direct sequencing of the eukaryotes present in the pitcher plant fluid enables us to better understand how a host plant can shape and contribute to the genetic structure of its associated inquilines, and to ask whether genetic variation in the taxa are structured in a similar manner to the host plant. We used 454 amplicon-based metagenomics to demonstrate that the pattern of genetic diversity in many, but not all, of the eukaryotic community is similar to that of S. alata, providing evidence that associated eukaryotes share an evolutionary history with the host pitcher plant. Our work provides further evidence that a host plant can influence the evolution of its associated commensals. PMID:26788436
Baseball aerodynamics is governed by three phenomenological quantities: the coefficients of drag, lift, and moment, the latter determining the spin decay time constant. In past years, these quantities were studied mainly in wind tunnel experiments, whereby the forces on the baseball are measured directly. More recently, new tools are being used that focus on measuring accurate baseball trajectories, from which the forces can be inferred. These tools include high-speed motion analysis, video tracking of pitched baseballs (the PITCHf/x system), and Doppler radar tracking. In this contribution, I will discuss what these new tools are teaching us about baseball aerodynamics.
Wilson, Jacob M; Miller, Abraham L; Szymanski, David J; Duncan, Nevine M; Andersen, Jody C; Alcantara, Zane G; Morrison, Timothy J; Bergman, Christopher J
It is common among competitive baseball players to swing bats while in the batter's box in an attempt to improve their batting performance. Players use bats of different weights during this time, and only a few studies have evaluated the optimal bat weight to increase performance. Previous studies have not investigated the optimal rest period after a warm-up with bats of varying weights. Therefore, we tested the peak bat velocity of 16 National Collegiate Athletic Association Division II intercollegiate baseball players at 1, 2, 4, and 8 minutes, after warming up with bats of 5 different weights. Measured variables were peak bat velocity at peak acceleration (PVPA), peak bat velocity of the swing (PV), peak bat acceleration (PA), and time to reach peak acceleration (TPA) using a chronograph, which measured the batting velocity in real time every 10 milliseconds throughout the swing. A repeated measure analysis of variance was run to assess group, time, and group by time interactions. If any main effects were found, a Tukey post hoc was employed to locate differences. There were significant (p ≤ 0.05) time effects for PVPA, PV, and PA but not for TPA. The PVPA, PV, and PA all increased over time, peaking from 4 to 8 minutes. There were no significant differences in any of the variables among the 5 bat weights used in the warm-up (p > 0.05). However, there were significant differences in PVPA, PV, and PA after 2, 4, and 8 minutes of rest compared with the preexperimental warm-up and 1-minute post-warm-up. From a practical standpoint, batters should warm up early and quickly in the batter's box to maximize the amount of recovery time before they swing at the plate. In addition, batters may want to take their time getting ready at the plate or take some pitches while at-bat in an attempt to maximize performance. Alternatively, the data imply that pitchers should throw their fastest pitch near the beginning of the at-bat to correspond with the potentially slower bat
This study examined whether the home advantage varies for open-air, domed, or retractable-roof baseball stadia, and whether having the roof open or closed affects the home advantage in retractable-roof baseball stadia. Data from Major League Baseball (MLB) games played between 2001 and 2009 were analyzed for whether or not the presence of a home-advantage was dependent on the type of home stadium used. Home advantage was robust for all three types of stadia. A significant effect of stadium type on home advantage was found, with a greater home advantage for teams playing home games in domed stadia relative to open-air stadia, replicating a previous study. There was a greater home advantage for teams playing home games in domed stadia relative to retractable-roof stadia. No other differences in the home advantage were found; results are discussed in terms of familiarity with the facility.
Guo, Mindy Ming-Huey; Chuech, Leonard Shun-Jen; Yang, Cheng-Hsu; Wu, Chiung-Jen; Guo, Gary Bih-Fang
Popliteal artery occlusion is a rare vascular complication in athletes and has not been previously documented in baseball players. A 21-year-old male baseball player presented with a 10-month history of progressive claudication because of repeated trauma-induced popliteal artery occlusion from frequently practicing stealing bases by sliding down onto his right leg. He was found to have a transient deficiency in both protein C and protein S. The patient underwent percutaneous transluminal recanalization angioplasty followed by anticoagulation therapy, with good results. This case illustrates the importance of awareness of this potential complication in baseball athletes, work-up for a hypercoagulable state and the feasibility of angioplasty therapy in the management of ischemic limbs after trauma.
Adlassnig, Wolfram; Peroutka, Marianne; Lendl, Thomas
Background Carnivorous pitcher plants (CPPs) use cone-shaped leaves to trap animals for nutrient supply but are not able to kill all intruders of their traps. Numerous species, ranging from bacteria to vertrebrates, survive and propagate in the otherwise deadly traps. This paper reviews the literature on phytotelmata of CPPs. Pitcher Fluid as a Habitat The volumes of pitchers range from 0·2 mL to 1·5 L. In Nepenthes and Cephalotus, the fluid is secreted by the trap; the other genera collect rain water. The fluid is usually acidic, rich in O2 and contains digestive enzymes. In some taxa, toxins or detergents are found, or the fluid is extremely viscous. In Heliamphora or Sarracenia, the fluid differs little from pure water. Inquiline Diversity Pitcher inquilines comprise bacteria, protozoa, algae, fungi, rotifers, crustaceans, arachnids, insects and amphibia. The dominant groups are protists and Dipteran larvae. The various species of CPPs host different sets of inquilines. Sarracenia purpurea hosts up to 165 species of inquilines, followed by Nepenthes ampullaria with 59 species, compared with only three species from Brocchinia reducta. Reasons for these differences include size, the life span of the pitcher as well as its fluid. Mutualistic Activities Inquilines closely interact with their host. Some live as parasites, but the vast majority are mutualists. Beneficial activities include secretion of enzymes, feeding on the plant's prey and successive excretion of inorganic nutrients, mechanical break up of the prey, removal of excessive prey and assimilation of atmospheric N2. Conclusions There is strong evidence that CPPs influence their phytotelm. Two strategies can be distinguished: (1) Nepenthes and Cephalotus produce acidic, toxic or digestive fluids and host a limited diversity of inquilines. (2) Genera without efficient enzymes such as Sarracenia or Heliamphora host diverse organisms and depend to a large extent on their symbionts for prey utilization
Warden, Stuart J; Bogenschutz, Elizabeth D; Smith, Heather D; Gutierrez, Anthony R
Athletes participating in unilateral dominant sports are useful models for investigating skeletal responses to mechanical loading as they provide controlled evidence in the absence of completing a randomized controlled trial. Throwing athletes may be an additional model for this purpose as they overload their dominant upper extremity enabling the contralateral side to act as an internal control and load the bones of the upper extremity purely via the generation of internal (i.e. muscular) forces without superposition of externally applied loads (i.e. impact with an external object). The aim of this study was to investigate upper extremity bone adaptation in throwing athletes and explore factors that predict this adaptation. Two cohorts were recruited-male baseball players (throwers; n=15) and matched controls (controls; n=15). Each subject was assessed for shoulder range and strength, and upper extremity bone mass, structure and estimated strength. Throwers had substantially greater skeletal differences between their dominant and nondominant upper extremities than controls, indicating that throwing induces greater adaptation than induced by habitual loading of the dominant upper extremity. Bone adaptation in throwers was localized to the humerus, with the midshaft humerus in the dominant upper extremity of throwers having enhanced bone mass, structure and estimated strength. The largest effect was for estimated strength of the midshaft humerus which had 30% greater polar moment of inertia (I(P)) in throwers and suggests adaptation to resist torsional loads. The skeletal effect of throwing at the midshaft humerus was influenced by playing position with pitchers and catchers displaying greater dominant-to-nondominant differences than fielders, and was predicted by years throwing and dominant-to-nondominant difference in upper arm lean cross-sectional area. The latter two variables explained 67% of the variance in dominant-to-nondominant differences in I
Robb, Andrew; Sajko, Sandy
This report documents retrospectively a case of Posterior Interosseous Neuropathy (PIN) occurring in an elite baseball pitcher experiencing a deep ache in the radial aspect of the forearm and altered sensation in the dorsum of the hand on the throwing arm during his pitching motion. The initial clinical goal was to control for inflammation to the nerve and muscle with active rest, microcurrent therapy, low-level laser therapy, and cessation of throwing. Minimizing mechanosensitivity at the common extensor region of the right elbow and PIN, was achieved by employing the use of myofascial release and augmented soft tissue mobilization techniques. Neurodynamic mobilization technique was also administered to improve neural function. Implementation of a sport specific protocol for the purposes of maintaining throwing mechanics and overall conditioning was utilized. Successful resolution of symptomatology and return to pre-injury status was achieved in 5 weeks. A review of literature and an evidence-based discussion for the differential diagnoses, clinical examination, diagnosis, management and rehabilitation of PIN is presented. PMID:20037695
Rottloff, Sandy; Stieber, Regina; Maischak, Heiko; Turini, Florian G; Heubl, Günther; Mithöfer, Axel
Carnivory in plants is an adaptation strategy to nutrient-poor environments and soils. Carnivorous plants obtain some additional mineral nutrients by trapping and digesting prey; the genus Nepenthes is helped by its specialized pitcher traps. To make the nutrients available, the caught prey needs to be digested, a process that requires the concerted activity of several hydrolytic enzymes. To identify and investigate the various enzymes involved in this process, fluid from Nepenthes traps has been analysed in detail. In this study, a novel type of Nepenthes endochitinase was identified in the digestion fluid of closed pitchers. The encoding endochitinase genes have been cloned from eight different Nepenthes species. Among these, the deduced amino acid sequence similarity was at least 94.9%. The corresponding cDNA from N. rafflesiana was heterologously expressed, and the purified protein, NrChit1, was biochemically characterized. The enzyme, classified as a class III acid endochitinase belonging to family 18 of the glycoside hydrolases, is secreted into the pitcher fluid very probably due to the presence of an N-terminal signal peptide. Transcriptome analyses using real-time PCR indicated that the presence of prey in the pitcher up-regulates the endochitinase gene not only in the glands, which are responsible for enzyme secretion, but at an even higher level, in the glands' surrounding tissue. These results suggest that in the pitchers' tissues, the endochitinase as well as other proteins from the pitcher fluid might fulfil a different, primary function as pathogenesis-related proteins.
Sota, Teiji; Mogi, Motoyoshi
Two mosquito species of the subgenus Stegomyia (genus Aedes) (Diptera: Culicidae) on the islands of Palau and Yap (Aedes dybasi Bohart and Aedes maehleri Bohart) are adapted to aquatic habitats occupied by Nepenthes pitcher plants. To reveal the origin of these pitcher plant mosquitoes, we attempted a molecular phylogenetic analysis with 11 Stegomyia species by using sequence data from mitochondrial cytochrome oxidase subunit I and 16SrRNA genes as well as the nuclear 28SrRNA gene. Ae. dybasi, a pitcher plant specialist, was sister to Aedes palauensis Bohart within the scutellaris group from the same islands. Ae. maehleri, an opportunistic pitcher plant mosquito, was in a distinct lineage related to the scutellaris group. The adaptation to pitcher plants could have occurred independently in these two species, and recent differentiation of the pitcher plant mosquito Ae. dybasi from the nonpitcher plant mosquito Ae. palauensis was suggested by a relatively small sequence divergence between these species. We also discuss the implications of this analysis for the phylogeny of some other Stegomyia species.
Schulze, W; Schulze, E D; Pate, J S; Gillison, A N
This study investigated the nitrogen (N) acquisition from soil and insect capture during the growth of three species of pitcher plants, Nepenthes mirabilis, Cephalotus follicularis and Darlingtonia californica. (15)N/(14)N natural abundance ratios (δ(15)N) of plants and pitchers of different age, non-carnivorous reference plants, and insect prey were used to estimate proportional contributions of insects to the N content of leaves and whole plants. Young Nepenthes leaves (phyllodes) carrying closed pitchers comprised major sinks for N and developed mainly from insect N captured elsewhere on the plant. Their δ(15)N values of up to 7.2‰ were higher than the average δ(15)N value of captured insects (mean δ(15)N value = 5.3‰). In leaves carrying old pitchers that are acting as a N source, the δ(15)N decreased to 3.0‰ indicating either an increasing contribution of soil N to those plant parts which in fact captured the insects or N gain from N2 fixation by microorganisms which may exist in old pitchers. The δ(15)N value of N in water collected from old pitchers was 1.2‰ and contained free amino acids. The fraction of insect N in young and old pitchers and their associated leaves decreased from 1.0 to 0.3 mg g(-1). This fraction decreased further with the size of the investigated tiller. Nepenthes contained on average 61.5 ± 7.6% (mean ± SD, range 50-71%) insect N based on the N content of a whole tiller. In the absence of suitable non-carnivorous reference plants for Cephalotus, δ(15)N values were assessed across a developmental sequence from young plants lacking pitchers to large adults with up to 38 pitchers. The data indicated dependence on soil N until 4 pitchers had opened. Beyond that stage, plant size increased with the number of catching pitchers but the fraction of soil N remained high. Large Cephalotus plants were estimated to derive 26 ± 5.9% (mean ± SD of the three largest plants; range: 19-30%) of the N from insects
Kagan, David; Nathan, Alan M.
The classic experiment to measure the drag coefficient involves dropping coffee filters. Wouldn't it be more fun to try something different? In fact, an experiment on the drag force is conducted nearly 4000 times a day during the baseball season and you have free access to this PITCHf/x data!2
Ball, Carolyn; And Others
A model and method for developing a valid and reliable paper-and-pencil test for evaluating the technical knowledge of baseball coaches in the National Coaching Certification Program (NCCP) in Canada are discussed. Development of a general theoretical and operational model for the evaluation of NCCP coaches in all sports are also studied. The…
Bennett, G; Maneval, M
Chelladurai and Saleh's Leadership Scale for Sports was administered to 52 elite Dixie Youth baseball coaches. Analyses indicated that subjects scored high in positive feedback, training and instruction, and social support, moderate in democratic behavior, and low in autocratic behavior. These results seem to support the validity of using the scale to compare coaching behavior.
Barrett, David D.; Burton, Allen W.
Examined the form of 3,684 throws made by 100 collegiate baseball players in relation to position, distance, and active and inactive situations. Videotapes of all throws for 94 half innings showed that interrater reliability of task, environment, and performance measures were all acceptable to excellent, indicating that qualitative aspects of…
Jarosik, Kris Maldre; Sweeney, Jenny McMillen
In this article, the authors demonstrate how a series of National Archives documents related to professional baseball players and the military draft can launch a lesson on the American home front during World War I, as the 100th anniversary approaches.
View of baseball back stop on sports field at intersection of South Twenty-Sixth Street and Foothill Avenue. Buildings No. 36, 37, 38, and 35, from to right. Foothill Avenue at center rear. Looking east-northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA
Sullivan, Suzanne, Comp.
This annotated bibliography lists works by several sports historians and essayists, as well as sociologists and sports journalists who address the question, "Why baseball?", and examine the reasons for our national love of the game, the myths, and the legends. Annotations have been excerpted from summaries and reviews in the "Book Review Digest."…
Kalist, David E.; Peng, Yingwei
The authors used duration analysis to examine the longevity of Major League Baseball players. Using data on players who were born between 1945 and 1964, the authors found that the hazard rate of death for players who only attended high school was almost 2.0 times higher than those players who attended a 4-year university, evidence that the…
Suspenski, Thomas J.
Cryotherapy (the use of ice and exercise to rehabilitate athletic injuries) can be an effective method of treating baseball injuries. It is generally agreed that ice is appropriate for the first 24 to 48 hours, but there is disagreement over its use beyond 72 hours. Some physicians and trainers support the use of heat with either exercise or rest,…
Kagan, David; Nathan, Alan M.
The classic experiment to measure the drag coefficient involves dropping coffee filters. Wouldn't it be more fun to try something different? In fact, an experiment on the drag force is conducted nearly 4000 times a day during the baseball season and you have free access to this PITCHf/x data!
Fidler, Merrie A.
This presentation provides an historical sketch of the All-American Girls' Baseball League (AAGBBL). The League was created in 1942 as the All-American Girls' Softball League, by Philip K. Wrigley. He initiated the League as a non-profit organization governed by a board of three trustees. Mr. Wrigley's basic motivation for creating the AAGSBL was…
Gerstman, Victoria; Raue, Brian
In a study inspired by the famous humidor of the Colorado Rockies of Major League Baseball, we have measured the effects of temperature and humidity on the elasticity of official Major League baseballs. The elasticity, e, also referred to as the coefficient of restitution (COR), of the baseballs was determined by dropping the balls from a fixed height onto a concrete floor and determining the speed of the ball after the initial impact. Corrections for air drag were made to the measured COR. Measurements were done for baseballs stored under a wide variety of conditions that included storage in the freezer compartment of a household refrigerator, storage in an 80^rcC oven with varying humidity conditions, and storage in a crude humidor. The balls were tested over a period of several hours after removal to nominal conditions. Our results show a linear increase of the COR with increasing temperature, as well as a nearly linear decrease in the COR as water mass is increased. Using the results of our measurements, we have determined the effects of temperature and humidity on batted-ball speeds and flight distances at the Rockies' home field.
Windsor Univ. (Ontario). Faculty of Physical and Health Education.
Results are reported of a research effort designed to provide a comprehensive profile of the characteristics of members of the Canadian National Baseball Team. The subjects of the study were candidates for the team. The control group consisted of top level amateur baseball players from Windsor. Four examinations were made: 1) physiological tests…
Although Japanese schools are generally considered to be one of the most gender-equitable social institutions in Japan, they play an important role in helping to reproduce and naturalize the notion of sex-based separate spheres, through endorsing the maintenance of such separate spheres in extracurricular sports clubs, such as baseball, where…
Collins, Christy L; McKenzie, Lara B; Roberts, Kristin J; Fields, Sarah K; Comstock, R Dawn
Although mouthguards are effective, inexpensive, easy to use, and readily available, this form of protective equipment has been underutilized. "Impulsive delay discounting" (an index of impulsive behavior) among high school athletes may help explain their decision making regarding use of protective equipment such as mouthguards. We investigated the relationship between high school baseball, softball, and basketball players' mouthguard use, impulsive delay discounting, and the precaution adoption process model (a behavior change theory). A convenience sample of boys' and girls' basketball and baseball/softball players at 21 high schools in the Greater Columbus, Ohio, metro area completed a self-administered survey that captured their demographic information, knowledge, attitudes, and beliefs regarding mouthguard use, impulsive delay discounting, and precaution adoption process model stage. We surveyed a total of 1636 students (55.9 % male, 43.8 % female, 0.3 % unknown). Only 12.3 % reported using a mouthguard either every time or sometimes during practice or competition. The primary reasons reported for not wearing mouthguards were they were not required to (65.3 %) and that the athletes could not breathe or talk while wearing one (61.5 %). These reasons were consistent across sex and sport. Most athletes reported that their coaches (87.3 %) and parents (64.5 %) had never talked to them about wearing a mouthguard. Lower precaution adoption process model stage was significantly associated with higher impulsivity (p < 0.001) and higher delayed discounting (p = 0.016) after adjusting for school, sport, and sex. Voluntary mouthguard use among high school athletes playing basketball and baseball/softball remains low despite the risk of dental injury in these sports. Effective, evidence-based, targeted, and tailored interventions to improve adolescent athletes' use of mouthguards to prevent sports-related dental injuries should be based on the specific
Wasser, Joseph G; Zaremski, Jason L; Herman, Daniel C; Vincent, Heather K
The prevalence of low back pain (LBP) among active baseball players ranges between 3 and 15%. The execution of baseball-specific manoeuvres, such as pitching or batting, may be related to the onset of LBP. These baseball motions are complex and require appropriate activation of the core musculature to produce a well-timed motion with forces minimized at the extremities. The spine, core and back musculature are involved with acceleration and deceleration of rotational motions. This narrative review synopsizes the available evidence of the prevalence of and mechanical factors underlying LBP in the baseball population. Possible mechanical mechanisms linking baseball play to LBP include aberrant motion, improper timing, high lumbar stress due to mechanical loading and lumbopelvic strength deficits. Potential clinical implications relating to these possible mechanical mechanisms will also be highlighted. The state of the evidence suggests that there are deficits in understanding the role of baseball motion and playing history in the development of spine conditions.
Blinde, Elaine M; McCallister, Sarah G
This study explored the extent and type of men and women's relationship to baseball at the end of the 20th century. Unobtrusive observations of the behaviors and comments of visitors to the National Baseball Hall of Fame and Museum in Cooperstown, New York, were undertaken during a 7-day period to explore how men and women related to baseball. The "doing of gender" by visitors was observed in several areas: (a) historical and personal connection to baseball, (b) ability to experience a bond with others through baseball, and (c) approach to touring the Hall of Fame and Museum. Women generally were seen as outsiders and peripheral to baseball and often connected to the sport in a manner different from men.
Bohn, Holger Florian; Thornham, Daniel George; Federle, Walter
Camponotus schmitzi ants live in symbiosis with the Bornean pitcher plant Nepenthes bicalcarata. Unique among ants, the workers regularly dive and swim in the pitcher's digestive fluid to forage for food. High-speed motion analysis revealed that C. schmitzi ants swim at the surface with all legs submerged, with an alternating tripod pattern. Compared to running, swimming involves lower stepping frequencies and larger phase delays within the legs of each tripod. Swimming ants move front and middle legs faster and keep them more extended during the power stroke than during the return stroke. Thrust estimates calculated from three-dimensional leg kinematics using a blade-element approach confirmed that forward propulsion is mainly achieved by the front and middle legs. The hind legs move much less, suggesting that they mainly serve for steering. Experiments with tethered C. schmitzi ants showed that characteristic swimming movements can be triggered by submersion in water. This reaction was absent in another Camponotus species investigated. Our study demonstrates how insects can use the same locomotory system and similar gait patterns for moving on land and in water. We discuss insect adaptations for aquatic/amphibious lifestyles and the special adaptations of C. schmitzi to living on an insect-trapping pitcher plant.
Pavlovič, Andrej; Slováková, Ludmila; Šantrůček, Jiří
The pitcher plant Nepenthes ampullaria has an unusual growth pattern, which differs markedly from other species in the carnivorous genus Nepenthes. Its pitchers have a reflexed lid and sit above the soil surface in a tighly packed 'carpet'. They contain a significant amount of plant-derived materials, suggesting that this species is partially herbivorous. We tested the hypothesis that the plant benefits from leaf litter utilization by increased photosynthetic efficiency sensu stricto cost/benefit model. Stable nitrogen isotope abundance indicated that N. ampullaria derived around 41.7 ± 5.5% of lamina and 54.8 ± 7.0% of pitcher nitrogen from leaf litter. The concentrations of nitrogen and assimilation pigments, and the rate of net photosynthesis (A(N)), increased in the lamina as a result of feeding, but did not increase in the trap. However, maximal (F(v) /F(m)) and effective photochemical quantum yield of photosystem II (Φ(PSII)) were unaffected. Our data indicate that N. ampullaria benefits from leaf litter utilization and our study provides the first experimental evidence that the unique nitrogen sequestration strategy of N. ampullaria provides benefits in term of photosynthesis and growth.
Gotelli, Nicholas J; Smith, Aidan M; Ellison, Aaron M; Ballif, Bryan A
The array of biomolecules generated by a functioning ecosystem represents both a potential resource for sustainable harvest and a potential indicator of ecosystem health and function. The cupped leaves of the carnivorous pitcher plant, Sarracenia purpurea, harbor a dynamic food web of aquatic invertebrates in a fully functional miniature ecosystem. The energetic base of this food web consists of insect prey, which is shredded by aquatic invertebrates and decomposed by microbes. Biomolecules and metabolites produced by this food web are actively exchanged with the photosynthesizing plant. In this report, we provide the first proteomic characterization of the sacrophagid fly (Fletcherimyia fletcheri), the pitcher plant mosquito (Wyeomyia smithii), and the pitcher-plant midge (Metriocnemus knabi). These three arthropods act as predators, filter feeders, and shredders at distinct trophic levels within the S. purpurea food web. More than 50 proteins from each species were identified, ten of which were predominantly or uniquely found in one species. Furthermore, 19 peptides unique to one of the three species were identified using an assembled database of 100 metazoan myosin heavy chain orthologs. These molecular signatures may be useful in species monitoring within heterogeneous ecosystem biomass and may also serve as indicators of ecosystem state.
Chia, Tet Fatt; Aung, Hnin Hnin; Osipov, Anatoly N; Goh, Ngoh Khang; Chia, Lian Sai
A study of the involvement of free oxygen radicals in trapping and digestion of insects by carnivorous plants was the main goal of the present investigation. We showed that the generation of oxygen free radicals by pitcher fluid of Nepenthes is the first step of the digestion process, as seen by EPR spin trapping assay and gel-electrophoresis. The EPR spectrum of N. gracilis fluid in the presence of DMPO spin trap showed the superposition of the hydroxyl radical spin adduct signal and of the ascorbyl radical signal. Catalase addition decreased the generation of hydroxyl radicals showing that hydroxyl radicals are generated from hydrogen peroxide, which can be derived from superoxide radicals. Gel-electrophoresis data showed that myosin, an abundant protein component of insects, can be rapidly broken down by free radicals and protease inhibitors do not inhibit this process. Addition of myoglobin to the pitcher plant fluid decreased the concentration of detectable radicals. Based on these observations, we conclude that oxygen free radicals produced by the pitcher plant aid in the digestion of the insect prey.
Tanabe, S; Nakahira, J; Bando, E; Yamaguchi, H; Miyamoto, H; Yamamoto, A
We have reported three cases of fatigue fracture of the ulna in male pitchers of fast-pitch softball. To elucidate the etiology of injury, we first selected three healthy male and three healthy female pitchers from a well-trained college team and analyzed their forearm movement by high-speed cinematography. This showed slight flexion of the elbow joints during wind-up motion, dorsal flexion of the hand joints upon releasing the ball, and extreme pronation of the forearms during the follow-through. We then took 8 mm CT scanning sections of the forearms. Using these images, we investigated shapes and areas of cross-sections of the ulna and its cortical and cancellous bones from the elbow to the hand joints. Our results reveal that the shapes of the sections are significantly different from circles at around the center of the ulna, and the cross-sectional areas are smaller in the middle one-third of the ulna than in other parts. These observations imply that fatigue fractures of the ulna in pitchers of fast-pitch softball must be torsionally induced, tending to occur at the middle one-third of the bone.
Greenwood, Melinda; Clarke, Charles; Lee, Ch'ien C; Gunsalam, Ansou; Clarke, Rohan H
The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers) that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids.Although the basis of this resource mutualism has been elucidated, many aspects are yet to be investigated. We sought to provide insights into the value of the mutualism to each participant. During initial observations we discovered that the summit rat, R. baluensis, also feeds on sugary exudates of N. rajah pitchers and defecates into them, and that this behavior appears to be habitual. The scope of the study was therefore expanded to assess to what degree N. rajah interacts with the small mammal community.We found that both T. montana and R. baluensis are engaged in a mutualistic interaction with N. rajah. T .montana visit pitchers more frequently than R. baluensis, but daily scat deposition rates within pitchers do not differ, suggesting that the mutualistic relationships are of a similar strength. This study is the first to demonstrate that a mutualism exists between a carnivorous plant species and multiple members of a small mammal community. Further, the newly discovered mutualism between R. baluensis and N. rajah represents only the second ever example of a multidirectional resource-based mutualism between a mammal and a carnivorous plant.
Kagan, David; Atkinson, David
The only published scientific data on the effect of humidity on baseballs known to the authors is contained in Robert Adair's book The Physics of Baseball: "long flies hit with balls stored under conditions of extreme humidity could be expected to fall as much as 30 feet short of the distance expected for normal balls." In this paper we report on our measurements of the coefficient of restitution of baseballs as a function of the humidity at which they have been stored.
Post, Andrew; Karton, Clara; Blaine Hoshizaki, T; Gilchrist, Michael D; Bailes, Julian
The purpose of this research was to examine how four different types of baseball helmets perform for baseball impacts when performance was measured using variables associated with concussion. A helmeted Hybrid III headform was impacted by a baseball, and linear and rotational acceleration as well as maximum principal strain were measured for each impact condition. The method was successful in distinguishing differences in design characteristics between the baseball helmets. The results indicated that there is a high risk of concussive injury from being hit by a ball regardless of helmet worn.
Solomito, Matthew J.; Garibay, Erin J.; Õunpuu, Sylvia; Tate, Janet P.; Nissen, Carl W.
Background: There are a number of studies showing that fastball pitches place greater loads on the shoulder and elbow than the curveball; however, the results of these studies are inconsistent, especially in collegiate-level pitchers. There is also discussion that sliders may produce substantially greater loads than other breaking pitches, but there is little scientific evidence to support this claim. Hypothesis: The curveball and slider/cutter produce greater moments on the shoulder and elbow compared with the fastball and change-up. Study Design: Descriptive laboratory study. Methods: Thirty-six collegiate pitchers were evaluated using motion analysis techniques. All subjects pitched a fastball and a change-up, 29 pitched a curveball, and 20 pitched a slider/cutter. Kinematic data were collected, and kinetic (joint moment) data were computed using standard protocols. A random-intercept, mixed-model regression analysis was used to assess differences in joint moments between pitch types. Results: The greatest glenohumeral and elbow moments were found when pitchers were pitching the fastball (mean ± standard deviation: 80.8 ± 15.5 and 79.2 ± 16.9 N·m, respectively) and the lowest when pitching the change-up (73.2 ± 14.5 and 71.6 ± 15.0 N·m, respectively). The moments produced by the slider/cutter and curveball were similar (74.9 ± 16.4 and 75.6 ± 15.5 N·m at the elbow, respectively) and significantly lower than the moments produced by the fastball (P < .0001). Results also indicate that the change-up produced the lowest joint moments compared with other pitch types. Conclusion: This study shows that the fastball and not the curveball or slider/cutter produced the greatest moments on the college pitcher’s glenohumeral and elbow joints, as previously believed. The study also shows that the change-up may be the safest of the 4 pitch types analyzed. Clinical Relevance: There is a long-held belief that throwing breaking pitches, specifically the slider and
Bauer, Ulrike; Federle, Walter; Seidel, Hannes; Grafe, T Ulmar; Ioannou, Christos C
Carnivorous Nepenthes pitcher plants capture arthropods with specialized slippery surfaces. The key trapping surface, the pitcher rim (peristome), is highly slippery when wetted by rain, nectar or condensation, but not when dry. As natural selection should favour adaptations that maximize prey intake, the evolution of temporarily inactive traps seems paradoxical. Here, we show that intermittent trap deactivation promotes 'batch captures' of ants. Prey surveys revealed that N. rafflesiana pitchers sporadically capture large numbers of ants from the same species. Continuous experimental wetting of the peristome increased the number of non-recruiting prey, but decreased the number of captured ants and shifted their trapping mode from batch to individual capture events. Ant recruitment was also lower to continuously wetted pitchers. Our experimental data fit a simple model that predicts that intermittent, wetness-based trap activation should allow safe access for 'scout' ants under dry conditions, thereby promoting recruitment and ultimately higher prey numbers. The peristome trapping mechanism may therefore represent an adaptation for capturing ants. The relatively rare batch capture events may particularly benefit larger plants with many pitchers. This explains why young plants of many Nepenthes species additionally employ wetness-independent, waxy trapping surfaces.
Bauer, Ulrike; Federle, Walter; Seidel, Hannes; Grafe, T. Ulmar; Ioannou, Christos C.
Carnivorous Nepenthes pitcher plants capture arthropods with specialized slippery surfaces. The key trapping surface, the pitcher rim (peristome), is highly slippery when wetted by rain, nectar or condensation, but not when dry. As natural selection should favour adaptations that maximize prey intake, the evolution of temporarily inactive traps seems paradoxical. Here, we show that intermittent trap deactivation promotes ‘batch captures' of ants. Prey surveys revealed that N. rafflesiana pitchers sporadically capture large numbers of ants from the same species. Continuous experimental wetting of the peristome increased the number of non-recruiting prey, but decreased the number of captured ants and shifted their trapping mode from batch to individual capture events. Ant recruitment was also lower to continuously wetted pitchers. Our experimental data fit a simple model that predicts that intermittent, wetness-based trap activation should allow safe access for ‘scout’ ants under dry conditions, thereby promoting recruitment and ultimately higher prey numbers. The peristome trapping mechanism may therefore represent an adaptation for capturing ants. The relatively rare batch capture events may particularly benefit larger plants with many pitchers. This explains why young plants of many Nepenthes species additionally employ wetness-independent, waxy trapping surfaces. PMID:25589604
Schöner, Caroline R; Schöner, Michael G; Kerth, Gerald; Grafe, T Ulmar
Interspecific relationships such as mutualism and parasitism are major drivers of biodiversity. Because such interactions often comprise more than two species, ecological studies increasingly focus on complex multispecies systems. However, the spatial heterogeneity of multi-species interactions is often poorly understood. Here, we investigate the unusual interaction of a bat (Kerivoula hardwickii hardwickii) and two pitcher plant species (Nepenthes hemsleyana and N. bicalcarata) whose pitchers serve as roost for bats. Nepenthes hemsleyana offers roosts of higher quality, indicated by a more stable microclimate compared to N. bicalcarata but occurs at lower abundance and is less common than the latter. Whereas N. hemsleyana benefits from the roosting bats by gaining nitrogen from their feces, the bats' interaction with N. bicalcarata seems to be commensal or even parasitic. Bats stayed longer in roosts of higher quality provided by N. hemsleyana and preferred them to pitchers of N. bicalcarata in a disturbance experiment. Moreover, bats roosting only in pitchers of N. hemsleyana had a higher body condition and were less infested with parasites compared to bats roosting in pitchers of N. bicalcarata. Our study shows how the local supply of roosts with different qualities affects the behavior and status of their inhabitants and-as a consequence-how the demand of the inhabitants can influence evolutionary adaptations of the roost providing species.
Hennessy, Dwight A; Schwartz, Stephen
Parents from two baseball leagues completed questionnaires regarding their likelihood of engaging in various aggressive behaviors (yelling, swearing, shoving, fighting, humiliating) toward targets at youth baseball games (other spectators, umpires, coaches, other players, their child). Overall, the likelihood of all forms of aggression was very low, particularly physical aggression and swearing. Hierarchical entry stepwise regressions were calculated to determine predictors of yelling and humiliating using demographics, trait aggression, anger, hostility, and vengeance as predictors. Parents with greater hostility reported a greater likelihood of humiliating a child's teammate, while those with elevated trait anger reported a greater likelihood of yelling at other spectators. Finally, parents with a more vengeful attitude reported a greater likelihood of humiliating umpires.
Farhadian, Joshua A; Tlougan, Brook E; Adams, Brian B; Leventhal, Jonathan S; Sanchez, Miguel R
Each year in the United States over 80 million people participate in bat-and-ball sports, for example baseball and softball. Cricket, the world's second most popular sport, is enjoyed by hundreds of millions of participants in such countries as India, Pakistan, Australia, New Zealand, Bangladesh, South Africa, West Indies, Sri Lanka, United Kingdom, and Zimbabwe. Although any player can develop skin disease as a result of participation in these bat-and-ball sports, competitive team athletes are especially prone to skin problems related to infection, trauma, allergy, solar exposure, and other causes. These diseases can produce symptoms that hinder individual athletic performance and participation. In this review, we discuss the diagnosis and best-practice management of skin diseases that can develop as a result of participation in baseball, softball, and cricket.
A baseball batting simulation was used to investigate the information used to hit a baseball. Measures of spatial and temporal swing accuracy were used to test whether batters (a) use speed to estimate pitch height, (b) initiate a constant swing duration at a fixed time to contact, (c) are influenced by the history of previous pitches and pitch count, and (d) use rotation direction. Batters were experienced college players. Pitch speed variance led to predictable spatial errors, and spatial accuracy was worse than temporal accuracy. Swing duration was generally variable. The history of the previous 3 pitches and the pitch count had significant effects on accuracy, and performance improved when rotation cues were added. There were significant effects of expertise on hitting strategy.
Huber, Michael; Glen, Andrew
Three sets of rare baseball events--pitching a no-hit game, hitting for the cycle, and turning a triple play--offer excellent examples of events whose occurrence may be modeled as Poisson processes. That is, the time of occurrence of one of these events doesn't affect when we see the next occurrence of such. We modeled occurrences of these three…
Miyazaki, Alberto Naoki; Fregoneze, Marcelo; Santos, Pedro Doneux; da Silva, Luciana Andrade; do Val Sella, Guilherme; Ishioka, Fábio Eduardo; Rosa, João Roberto Polydoro; Estelles, José Renato Depari; Checchia, Sérgio Luiz
Objective: The objective of this study was to evaluate the rehabilitation results among baseball players who presented pain and medial rotation deficit in their shoulders. Methods: Out of 55 baseball players assessed between April and June 2009, it was observed that 20 presented pain at some instant during throwing movements. They were advised to undergo a rehabilitation program with exercises to stretch the posterior capsule and reinforce the muscles of the scapular belt, especially the lateral rotators. Eighteen patients followed the advice, while two were lost from the follow-up. The parameters evaluated were: pain, range of motion, strength before the program and strength after the end of the program. Results: Comparing the initial and final assessments, we observed mean increases as follows: 10° of elevation (p = 0.001); three vertebral levels of medial rotation (p < 0.001); 20° of medial rotation at 90° abduction (p < 0.001); and 26° of range of motion (p < 0.001). Regarding strength, elevation force increased by 3 kgf (p = 0.002) and lateral rotation force increased by 1 kgf (p = 0.020). Out of the 18 baseball players studied, the pain level improved in 16, while two continued to present pain and underwent magnetic resonance imaging, which showed lesions for surgical treatment. Conclusion: The rehabilitation program conducted among the baseball players was effective and enabled increases in medial rotation, elevation, range of motion and strength of elevation and lateral rotation, consequently producing pain improvements in most of the players. PMID:27042626
Nakamoto, Hiroki; Mori, Shiro
The purpose of this study was to examine whether the baseball players' shorter Go/Nogo reaction time (RT) was influenced by stimulus-response compatibility (SRC) effects. To accomplish this purpose, we examined RTs and event-related potential components in three Go/Nogo tasks, manipulating stimulus-response relations. The participants were nine college baseball players (Baseball) and nine college non-baseball players (Control). Task conditions were the following: spatial condition with baseball batting-specific S-R mapping (Spatial-BB) demands response execution or inhibition corresponding to spatial stimulus location. This condition was similar to the stimulus-response relations in baseball batting. The other two tasks demand their response based on the stimulus location or colors. These tasks did not have any baseball-specific stimulus-response relations. As a result of RTs, baseball players revealed shorter RTs in Spatial-BB than other tasks, but the control group showed similar RTs among three tasks. In Go trials, as for the interval between stimulus and lateralized readiness potential (LRP) onset which is the duration to the end of response selection, baseball players had shorter than control in Spatial-BB, whereas P300 latency and the interval between LRP and response did not show any difference between groups or among tasks. In Nogo trials, the augmented P300 amplitude of baseball players at frontal (Fz) was observed in Spatial-BB. The P300 amplitude in Nogo trials is often interpreted as the strength of inhibition. These results indicated that the facilitation of RTs in baseball players is likely due to a faster response selection and stronger inhibition caused by SRC effects in relation to specific S-R mapping.
Nathan, Alan M.
Measurements are presented of the Magnus force on a spinning baseball. The experiment utilizes a pitching machine to project the baseball horizontally, a high-speed motion analysis system to determine the initial velocity and angular velocity and to track the trajectory over 5m of flight, and a ruler to measure the total distance traversed. Speeds in the range v =50-110mph and spin rates ω (topspin or backspin) in the range 1500-4500rpm were utilized, corresponding to Reynolds numbers of Re =(1.1-2.4)×105 and spin factors S ≡Rω/v in the range 0.090-0.595. Least-squares fits were used to extract the initial parameters of the trajectory and to determine the lift coefficients. Comparison is made with previous measurements and parametrizations, and implications for the effect of spin on the flight of a baseball are discussed. The lift coefficient CL is found not to depend strongly on v at fixed values of S.
... United States Mint National Baseball Hall of Fame Commemorative Coin Program Design Competition ACTION: Notification of the Opening of the National Baseball Hall of Fame Commemorative Coin Program Design Competition... competition that will culminate in the Secretary of the Treasury's selection of the image for the...
Regoli, Robert M.; Hewitt, John D.; Munoz, Robert, Jr.; Regoli, Adam M.
While on the surface baseball cards may appear to be a mundane object of child's play, they are precious tools for examining U.S. society. Baseball cards not only hold a wealth of information regarding the players they feature they also reveal much about the state of society at the time of their production and the individuals who collect them. In…
Barney, Robert Knight
During its century and a half history, baseball has been given continued impetus by the development of new technologies in communication--the telegraph, the sports page, the radio and television. Perhaps the most important in the initial spread of baseball throughout America was the railroad. The completion of the Union Pacific Railroad in 1869…
... Promotion, San Francisco, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast... Bay off San Francisco, CA in support of the San Francisco Giants Baseball Game Promotion. This safety... Giants will sponsor the San Francisco Giants Baseball Game Promotion on July 16, 2010, on the...
Abel, Ernest L.; Kruger, Michael L.
The authors compared the longevity of all baseball players alive at the time of their induction into the Baseball Hall of Fame with age-matched controls who were likewise alive at the time of the Hall of Famer's induction, and also matched them for career length, player position, and body-mass index, to assess if fame in sports is associated with…
E. Abel and M. Kruger (2005) reported that the median life expectancy of Major League Baseball players after election to the Baseball Hall of Fame is 5 years shorter than that of players of the same age who are not elected to the Hall of Fame. This conclusion is surprising because there is no compelling explanation for such a dramatic reduction in…
Butterworth, Michael L.
Baseball has enjoyed its status as the "national pastime" in part because it has been associated with democracy. To the extent that baseball, as an institution of civil religion, fosters pluralism and inclusion, it can indeed be viewed in democratic terms. In recent years, the advent of conservative Christian events called "Faith Nights" threatens…
Eaves, Ted; Strack, Robert W.
In spite of policy bans and recommendations against spit tobacco (ST) use, baseball athletes have demonstrated ST prevalence rates ranging from 34% to 50% in high school, 42% in the National Collegiate Athletic Association (NCAA), and 50% in the professional ranks. To evaluate enforcement of ST bans, high school baseball coaches in North Carolina…
Auer, Richard E.; Knapp, Michael P.
The modern era of professional baseball playoffs began in 1903, when the champions of the American League and the National League played the first World Series. Except for one year, 1904, this playoff system was maintained until 1969. Beginning in 1969, each of the two leagues in Major League Baseball (MLB) was divided into two divisions to…
Mueller, Frederick O.; Marshall, Stephen W.; Kirby, Daniel P.
Examined injury patterns in Little League baseball players over time, using insurance data from 17,221,210 players. Ball-related injuries were the most common. Batters had the greatest number of such injuries. One-quarter of the injuries were considered severe, and 13 players died. Though youth baseball appears to be very safe, there are areas…
Percoco, James A.
Presents a lesson plan using original documents of the wartime correspondence between President Franklin Roosevelt and baseball commissioner Kenesaw Landis. Explores the status of baseball during World War II to determine the importance of sports in U.S. culture. Includes background information and copies of the correspondence. (DK)
Zingg, Paul J.
Using baseball as its focus, this article demonstrates the importance of sport in helping students understand certain central themes of United States history. Provides a brief history of baseball and reviews scholarly works on its influence in United States culture. (JDH)
Towers, Wayne M.
During the 1920s professional baseball emerged as both a mass sport and a mass media-reported sport. This emergence was accompanied by evolution and change in both radio broadcasting and newspaper sports writing. Live coverage of sporting events, particularly baseball's World Series, provided a part of radio's growth process that affected the…
Ellison, Aaron M; Gotelli, Nicholas J
Atmospheric transport and deposition of nutrients, especially nitrogen, is a global environmental problem with well-documented consequences for ecosystem dynamics. However, monitoring nitrogen deposition is relatively expensive, monitoring stations are widely spaced, and estimates and predicted impacts of nitrogen deposition are currently derived from spatial modeling and interpolation of limited data. Ombrotrophic ("rain-fed") bogs are nutrient-poor ecosystems that are especially sensitive to increasing nutrient input, and carnivorous plants, which are characteristic of these widespread ecosystem types, may be especially sensitive indicators of N deposition. Botanical carnivory is thought to have evolved in nutrient-poor and well-lit habitats such as bogs because the marginal benefits accruing from carnivory exceed the marginal photosynthetic costs associated with the maintenance of carnivorous organs. However, the production of carnivorous organs can be a phenotypically plastic trait. The northern pitcher plant, Sarracenia purpurea, produces leaves specialized for prey capture and nutrient uptake (pitchers) and leaves that are more efficient at photosynthesis (phyllodia). We hypothesized that relative allocation to these two types of leaves reflects ambient nitrogen availability. We manipulated nutrient availability to plants with leaf enrichment and whole-plot fertilization experiments. Increased nitrogen, but not phosphorus, reduced production of pitchers relative to phyllodia; this result provided empirical support for the cost-benefit model of the evolution of botanical carnivory. Because this phenotypic shift in leaf production occurs in ecological time, our results suggest that S. purpurea could be a reliable and inexpensive biological indicator of nitrogen deposition rates. This suggestion is supported by field observations across a geographic gradient of nitrogen deposition.
Moran, Jonathan A.; Gray, Laura K.; Clarke, Charles; Chin, Lijin
Background and Aims Nepenthes (Nepenthaceae, approx. 120 species) are carnivorous pitcher plants with a centre of diversity comprising the Philippines, Borneo, Sumatra and Sulawesi. Nepenthes pitchers use three main mechanisms for capturing prey: epicuticular waxes inside the pitcher; a wettable peristome (a collar-shaped structure around the opening); and viscoelastic fluid. Previous studies have provided evidence suggesting that the first mechanism may be more suited to seasonal climates, whereas the latter two might be more suited to perhumid environments. In this study, this idea was tested using climate envelope modelling. Methods A total of 94 species, comprising 1978 populations, were grouped by prey capture mechanism (large peristome, small peristome, waxy, waxless, viscoelastic, non-viscoelastic, ‘wet’ syndrome and ‘dry’ syndrome). Nineteen bioclimatic variables were used to model habitat suitability at approx. 1 km resolution for each group, using Maxent, a presence-only species distribution modelling program. Key Results Prey capture groups putatively associated with perhumid conditions (large peristome, waxless, viscoelastic and ‘wet’ syndrome) had more restricted areas of probable habitat suitability than those associated putatively with less humid conditions (small peristome, waxy, non-viscoelastic and‘dry’ syndrome). Overall, the viscoelastic group showed the most restricted area of modelled suitable habitat. Conclusions The current study is the first to demonstrate that the prey capture mechanism in a carnivorous plant is constrained by climate. Nepenthes species employing peristome-based and viscoelastic fluid-based capture are largely restricted to perhumid regions; in contrast, the wax-based mechanism allows successful capture in both perhumid and more seasonal areas. Possible reasons for the maintenance of peristome-based and viscoelastic fluid-based capture mechanisms in Nepenthes are discussed in relation to the costs and
Bazile, Vincent; Le Moguédec, Gilles; Marshall, David J.; Gaume, Laurence
Background and Aims Nepenthes pitcher plants have evolved modified leaves with slippery surfaces and enzymatic fluids that trap and digest prey, faeces and/or plant detritus. Although the fluid’s contribution to insect capture is recognized, the physico-chemical properties involved remain underexplored and may vary among species, influencing their diet type. This study investigates the contributions of acidity and viscoelasticity in the fluid’s capture efficiency of two ant and two fly species in four Nepenthes species with different nutrition strategies. Methods Four Nepenthes species were studied, namely N. rafflesiana, N. gracilis, N. hemsleyana and N. ampullaria. Fluid was collected from pitchers of varying ages from plants growing in the field and immediately transferred to glass vials, and individual ants (tribe Campotini, Fomicinae) and flies (Calliphora vomitoria and Drosophila melanogaster) were dropped in and observed for 5 min. Water-filled vials were used as controls. Survival and lifetime data were analysed using models applied to right-censored observations. Additional laboratory experiments were carried out in which C. vomitoria flies were immersed in pH-controlled aqueous solutions and observed for 5 min. Key Results Pitcher fluid differed among Nepenthes species as regards insect retention capacity and time-to-kill, with differences observed between prey types. Only the fluids of the reputedly insectivorous species were very acidic and/or viscoelastic and retained significantly more insects than the water controls. Viscoelastic fluids were fatal to flies and were able to trap the broadest diversity of insects. Younger viscoelastic fluids showed a better retention ability than older fluids, although with less rapid killing ability, suggesting that a chemical action follows a mechanical one. Insect retention increased exponentially with fluid viscoelasticity, and this happened more abruptly and at a lower threshold for flies compared with
Lestariningsih, Nanik; Setyaningsih, Denik
Pitcher plants (Nepenthes sp.) is a plant with unique shape either of shades of colors, pouch shape and its capability in catching insects. Pitcher plant (Nepenthes sp.) is one of the plants that protected under Law Number. 5 of 1990 about Conservation of Biological Resources and Ecosystem and Government Regulation Number 7/1999 about Preservation of Plants and Animals. Sebangau National Park is one of representative of peat swamp ecosystem and one of some types of pitcher plants (Nepenthes sp.) habitat. This study aimed to determine the types and diversity levels of pitcher plants (Nepenthes sp.) and the trapped insects inside in Sebangau National and to determine the differences of diversity levels of pitcher plants (Nepenthes sp.) and the trapped insects inside in the opened and closed forest in Sebangau National Park. The research type was conducted descriptive qualitative research. The method used survey method with purpossive sampling technique.The result of the study the number of pitcher plants (Nepenthes sp.) obtained in opened forest were three types consist of Nepenthes mirabilis, Nepenthes rafflesiana and Nepenthes gracilis with two types insects trapped inside those were Diptera ordo and Hymenoptera ordo. While the number of pitcher plants (Nepenthes sp.) obtained in closed forest as many as two types consist of Nepenthes ampullaria and Nepenthes rafflesiana with two type insects trapped inside those were Diptera ordo and Hymenoptera ordo. The results of the analysis calculation pitcher plants (Nepenthes sp.) species diversity index in opened and closed forest showed lower category. The diversity in row were 1 and 0,45 with H’ criteria ≤ 1 low diversity. The results of the study of insects trapped inside of pitcher plants (Nepenthes sp.) obtained in opened and closed forest showed low category. The diversity in a row were 0,63 and 0,52 with the criteria of H’ ≤ 1 low diversity.
Bott, Terry; Meyer, Gretchen A; Young, Erica B
* Plasticity of leaf nutrient content and morphology, and macronutrient limitation were examined in the northern pitcher plant, Sarracenia purpurea subsp. purpurea, in relation to soil nutrient availability in an open, neutral pH fen and a shady, acidic ombrotrophic bog, over 2 yr following reciprocal transplantation of S. purpurea between the wetlands. * In both wetlands, plants were limited by nitrogen (N) but not phosphorus (P) (N content < 2% DW(-1), N : P < 14) but photosynthetic quantum yields were high (F(V)/F(M) > 0.79). Despite carnivory, leaf N content correlated with dissolved N availability to plant roots (leaf N vs , r(2) = 0.344, P < 0.0001); carnivorous N acquisition did not apparently overcome N limitation. * Following transplantation, N content and leaf morphological traits changed in new leaves to become more similar to plants in the new environment, reflecting wetland nutrient availability. Changes in leaf morphology were faster when plants were transplanted from fen to bog than from bog to fen, possibly reflecting a more stressful environment in the bog. * Morphological plasticity observed in response to changes in nutrient supply to the roots in natural habitats complements previous observations of morphological changes with experimental nutrient addition to pitchers.
Biesmeijer, Jacobus C.; Giurfa, Martin; Koedam, Dirk; Potts, Simon G.; Joel, Daniel M.; Dafni, Amots
Several recent hypotheses, including sensory drive and sensory exploitation, suggest that receiver biases may drive selection of biological signals in the context of sexual selection. Here we suggest that a similar mechanism may have led to convergence of patterns in flowers, stingless bee nest entrances, and pitchers of insectivorous plants. A survey of these non-related visual stimuli shows that they share features such as stripes, dark centre, and peripheral dots. Next, we experimentally show that in stingless bees the close-up approach to a flower is guided by dark centre preference. Moreover, in the approach towards their nest entrance, they have a spontaneous preference for entrance patterns containing a dark centre and disrupted ornamentation. Together with existing empirical evidence on the honeybee's and other insects’ orientation to flowers, this suggests that the signal receivers of the natural patterns we examined, mainly Hymenoptera, have spontaneous preferences for radiating stripes, dark centres, and peripheral dots. These receiver biases may have evolved in other behavioural contexts in the ancestors of Hymenoptera, but our findings suggest that they have triggered the convergent evolution of visual stimuli in floral guides, stingless bee nest entrances, and insectivorous pitchers.
Bohn, Holger F; Federle, Walter
Pitcher plants of the genus Nepenthes have highly specialized leaves adapted to attract, capture, retain, and digest arthropod prey. Several mechanisms have been proposed for the capture of insects, ranging from slippery epicuticular wax crystals to downward-pointing lunate cells and alkaloid secretions that anesthetize insects. Here we report that perhaps the most important capture mechanism has thus far remained overlooked. It is based on special surface properties of the pitcher rim (peristome) and insect "aquaplaning." The peristome is characterized by a regular microstructure with radial ridges of smooth overlapping epidermal cells, which form a series of steps toward the pitcher inside. This surface is completely wettable by nectar secreted at the inner margin of the peristome and by rain water, so that homogenous liquid films cover the surface under humid weather conditions. Only when wet, the peristome surface is slippery for insects, so that most ant visitors become trapped. By measuring friction forces of weaver ants (Oecophylla smaragdina) on the peristome surface of Nepenthes bicalcarata, we demonstrate that the two factors preventing insect attachment to the peristome, i.e., water lubrication and anisotropic surface topography, are effective against different attachment structures of the insect tarsus. Peristome water films disrupt attachment only for the soft adhesive pads but not for the claws, whereas surface topography leads to anisotropic friction only for the claws but not for the adhesive pads. Experiments on Nepenthes alata show that the trapping mechanism of the peristome is also essential in Nepenthes species with waxy inner pitcher walls.
Chang, Edward S; Bishop, Meghan E; Baker, Dylan; West, Robin V
Baseball injuries from throwing and hitting generally occur as a consequence of the repetitive and high-energy motions inherent to the sport. Biomechanical studies have contributed to understanding the pathomechanics leading to injury and to the development of rehabilitation programs. Interval-based throwing and hitting programs are designed to return an athlete to competition through a gradual progression of sport-specific exercises. Proper warm-up and strict adherence to the program allows the athlete to return as quickly and safely as possible.
Camp, Christopher L; Conti, Matthew S; Sgroi, Terrance; Cammisa, Frank P; Dines, Joshua S
In recent years, increased attention has been paid to injuries occurring in Major League Baseball (MLB) players. Although most of the current orthopedic literature regarding baseball injuries pertains to the shoulder and elbow, lumbar spine injuries are another common reason for time out of play. Back and core injuries may represent as many as 12% of all injuries that result in time out of play from MLB. This high rate of injury is likely related to the critical role that the spine plays in every major baseball-related movement. Linking the upper extremities to the hips and lower extremities, a healthy, strong, and stable spine and core is a prerequisite for performance in all levels of baseball. It has been well documented that baseball players with poor spinal control and stabilization are at increased risk for future injury. Common etiologies of lumbar injuries include stress fractures, muscle injury, annular tears with or without disc herniation, facet joint pain, sacroiliac joint pain, and stenosis. This review discusses the epidemiology of spinal injuries in baseball. Special attention is paid to the role of the spine in baseball-related activities, common injuries, tips for making the correct diagnosis, treatment options, outcomes, rehabilitation, and injury prevention.
Szymanski, David J; Beiser, Erik J; Bassett, Kylie E; Till, Megan E; Medlin, Greg L; Beam, Jason R; DeRenne, Coop
A variety of warm-up devices are available to baseball players to use before their game at-bat. Past baseball research evaluating warm-up devices indicates that implements that are ±12% of standard game bat weight produce the greatest bat velocities for high school and intercollegiate players. The purpose of this study was to examine the effect of various warm-up devices on bat velocity (BV) of intercollegiate baseball players. Twenty-two Division I intercollegiate baseball players (age = 20.0 ± 1.5 years, height = 182.6 ± 8.3 cm, body mass = 91.4 ± 11.4 kg, lean body mass = 78.8 ± 8.9 kg, % body fat = 13.6 ± 3.8) participated in a warm-up with 1 of 10 weighted devices on separate days. Each of the 10 testing sessions consisted of a standardized warm-up, 3 dry swings as hard as possible with the assigned warm-up device, 2 comfortable dry swings with a standard game baseball bat followed by 3 game swings (20-second rest between swings) while hitting a baseball off of a batting tee with the same standard game baseball bat. Results indicated that there were no statistically significant differences in BV after using any of the 10 warm-up devices. For male intercollegiate baseball players, results indicate that warm-up devices varying from 623.7 to 2,721.5 g (22-96 oz.) did not change mean BV of a standard game baseball bat, suggesting that intercollegiate players can use any of the 10 warm-up devices in the on-deck circle and maintain their BV. Therefore, personal preference as to which warm-up implement to use in the on-deck circle is advised.
Pasque, Charles B; Pearson, Clark; Margo, Bradley; Ethel, Robert
We present a case report of a college baseball player who sustained a blunt-trauma, distal-third ulna fracture from a thrown ball with delayed presentation of ulnar nerve palsy. Even after his ulna fracture had healed, the nerve injury made it difficult for the athlete to control a baseball while throwing, resulting in a delayed return to full baseball activity for 3 to 4 months. He had almost complete nerve recovery by 6 months after his injury and complete nerve recovery by 1 year after his injury.
Primm, Eric; Piquero, Nicole Leeper; Piquero, Alex R; Regoli, Robert M
A growing body of literature in a variety of disciplines has appeared over the last 20 years examining customer racial bias in the secondary sports card market; however, consensus on the matter has yet to emerge. In this article, we explore the more subtle ways that a player's race/ethnicity may affect the value of his sports card including a player's skin tone (light- to dark-skinned). Data were obtained for 383 black, Latino, and white baseball players who had received at least one vote for induction into Major League Baseball's Hall of Fame including their career performance statistics, rookie card price, card availability, Hall of Fame status, and skin tone. Findings indicate that card availability is the primary determinant of card value while a player's skin tone has no direct effect. Subsequent analysis demonstrates that a player's race (white/non-white) rather than skin tone did have an effect as it interacts with Hall of Fame status to influence his rookie card price.
Whitman, Richard L; Byers, Stacey E; Shively, Dawn A; Ferguson, Donna M; Byappanahalli, Muruleedhara
Sarracenia purpurea L., a carnivorous bog plant (also known as the pitcher plant), represents an excellent model of a well-defined, self-contained ecosystem; the individual pitchers of the plant serve as a microhabitat for a variety of micro- and macro-organisms. Previously, fecal indicator bacteria (Escherichia coli and enterococci) were shown as incidental contaminants in pitcher fluid; however, whether their occurrence in pitcher fluid is incidental or common has not been established. The purpose of this study was to investigate the occurrence, distribution, and growth potential of E. coli and enterococci in pitcher plant fluid from a protected bog in northwest Indiana. Escherichia coli and enterococci were recovered in pitcher fluids (n=43 plants), with mean densities (log CFU mL-1) of 1.28+/-0.23 and 1.97+/-0.27, respectively. In vitro experiments showed that E. coli growth in fluid not containing insects or indigenous organisms was directly proportional to the fluid concentration (growth was 10-fold in 24 h in 100% fluid); however, in the presence of other indigenous organisms, E. coli and enterococci were only sustained for 5 days at 26 degrees C. Pulsed-field gel electrophoresis (PFGE) analysis showed that the plant Enterococcus faecalis isolates were genetically distinct from the human isolates; identical PFGE patterns were observed among plant isolates that fell into one of six clonal groups. These findings suggest that (i) E. coli and enterococci occurrence in pitcher plants is rather common in the bog studied, although their originating source is unclear, and (ii) the pitcher fluid contains adequate nutrients, especially carbon and energy sources, to promote the growth of indicator bacteria; however, under natural conditions, the biotic factors (e.g., competition for nutrients) may restrict their growth.
Whitman, Richard L.; Byers, Stacey E.; Shively, Dawn A.; Ferguson, Donna M.; Byappanahalli, Muruleedhara N.
Sarracenia purpurea L., a carnivorous bog plant (also known as the pitcher plant), represents an excellent model of a well-defined, self-contained ecosystem; the individual pitchers of the plant serve as a microhabitat for a variety of micro- and macro-organisms. Previously, fecal indicator bacteria (Escherichia coli and enterococci) were shown as incidental contaminants in pitcher fluid; however, whether their occurrence in pitcher fluid is incidental or common has not been established. The purpose of this study was to investigate the occurrence, distribution, and growth potential of E. coli and enterococci in pitcher plant fluid from a protected bog in northwest Indiana. Escherichia coli and enterococci were recovered in pitcher fluids (n = 43 plants), with mean densities (log CFU mL-1) of 1.28 ± 0.23 and 1.97 ± 0.27, respectively. In vitro experiments showed that E. coli growth in fluid not containing insects or indigenous organisms was directly proportional to the fluid concentration (growth was 10-fold in 24 h in 100% fluid); however, in the presence of other indigenous organisms, E. coli and enterococci were only sustained for 5 days at 26 Â°C. Pulsed-field gel electrophoresis (PFGE) analysis showed that the plant Enterococcus faecalis isolates were genetically distinct from the human isolates; identical PFGE patterns were observed among plant isolates that fell into one of six clonal groups. These findings suggest that (i) E. coli and enterococci occurrence in pitcher plants is rather common in the bog studied, although their originating source is unclear, and (ii) the pitcher fluid contains adequate nutrients, especially carbon and energy sources, to promote the growth of indicator bacteria; however, under natural conditions, the biotic factors (e.g., competition for nutrients) may restrict their growth.
Higuchi, Hiroshi; Kiura, Toshiro
In the game of baseball, the knuckleball—so-called because the baseball is gripped with the knuckles in a certain position—is pitched in a way that introduces nearly no rotation, resulting in erratic flight paths which confuse batters. The “knuckleball” effect is believed to be caused by asymmetric flow separation over the baseball, but little is known about its flow physics. In the experiment described in this paper, the flow near the seams of the baseball is visualized thoroughly and the velocity vector fields near the surface and in the wake are obtained with Digital Particle Image Velocimetry. Depending on its position, the seam is found to trigger the boundary layer transition thus delaying the separation, or to cause separation itself. Three-dimensional wake patterns associated with specific ball orientations are identified and related to the force variations on the ball.
Brewster, Ryan; Bi, Wenya Linda; Smith, Timothy R; Gormley, William B; Dunn, Ian F; Laws, Edward R
Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society.
Miller, Thomas E; Moran, Emma R; terHorst, Casey P
Classic niche theory predicts that competing species will evolve to use different resources and interact less, whereas recent niche-converge ideas predict that species evolve to use similar resources and interact more. Most data supporting niche evolution are based on observations of contemporary niche use, whereas experimental support is quite sparse. We followed the evolution of four species of Protozoa during succession in the water-filled leaves of the pitcher plant, Sarracenia purpurea, and found that evolution in multispecies systems follows a surprising pattern. Over several hundred generations, weak competitors evolved to be stronger, while strong competitors evolved to become weaker, which does not conform to expectations of either niche divergence or convergence. Evolution in this system appears to occur in response to characteristics of a suite of several competitors in the community, rather than pairwise interactions. Ecologists may need to rethink the roles of competition and evolution in structuring communities.
In the past, both magnetospheric substorms and solar flares have almost exclusively been discussed in terms of explosive magnetic reconnection. Such a model may conceptually be illustrated by the so-called 'tippy-bucket model', which causes sudden unloading processes, namely a sudden (catastrophic, stochastic, and unpredictable) conversion of stored magnetic energy. However, recent observations indicate that magnetospheric substorms can be understood as a result of a directly driven process which can conceptually be illustrated by the 'pitcher model' in which the output rate varies in harmony with the input rate. It is also possible that solar flare phenomena are directly driven by a photospheric dynamo. Thus, explosive magnetic reconnection may simply be an unworkable hypothesis and may not be a puzzle to be solved as the primary energy supply process for magnetospheric substorms and solar flares.
Bauer, Ulrike; Paulin, Marion; Robert, Daniel; Sutton, Gregory P
Plants use rapid movements to disperse seed, spores, or pollen and catch animal prey. Most rapid-release mechanisms only work once and, if repeatable, regaining the prerelease state is a slow and costly process. We present an encompassing mechanism for a rapid, repeatable, passive-dynamic motion used by a carnivorous pitcher plant to catch prey. Nepenthes gracilis uses the impact of rain drops to catapult insects from the underside of the canopy-like pitcher lid into the fluid-filled trap below. High-speed video and laser vibrometry revealed that the lid acts as a torsional spring system, driven by rain drops. During the initial downstroke, the tip of the lid reached peak velocities similar to fast animal motions and an order of magnitude faster than the snap traps of Venus flytraps and catapulting tentacles of the sundew Drosera glanduligera. In contrast to these active movements, the N. gracilis lid oscillation requires neither mechanical preloading nor metabolic energy, and its repeatability is only limited by the intensity and duration of rainfall. The underside of the lid is coated with friction-reducing wax crystals, making insects more vulnerable to perturbations. We show that the trapping success of N. gracilis relies on the combination of material stiffness adapted for momentum transfer and the antiadhesive properties of the wax crystal surface. The impact-driven oscillation of the N. gracilis lid represents a new kind of rapid plant movement with adaptive function. Our findings establish the existence of a continuum between active and passive trapping mechanisms in carnivorous plants.
Bauer, Ulrike; Paulin, Marion; Robert, Daniel; Sutton, Gregory P.
Plants use rapid movements to disperse seed, spores, or pollen and catch animal prey. Most rapid-release mechanisms only work once and, if repeatable, regaining the prerelease state is a slow and costly process. We present an encompassing mechanism for a rapid, repeatable, passive-dynamic motion used by a carnivorous pitcher plant to catch prey. Nepenthes gracilis uses the impact of rain drops to catapult insects from the underside of the canopy-like pitcher lid into the fluid-filled trap below. High-speed video and laser vibrometry revealed that the lid acts as a torsional spring system, driven by rain drops. During the initial downstroke, the tip of the lid reached peak velocities similar to fast animal motions and an order of magnitude faster than the snap traps of Venus flytraps and catapulting tentacles of the sundew Drosera glanduligera. In contrast to these active movements, the N. gracilis lid oscillation requires neither mechanical preloading nor metabolic energy, and its repeatability is only limited by the intensity and duration of rainfall. The underside of the lid is coated with friction-reducing wax crystals, making insects more vulnerable to perturbations. We show that the trapping success of N. gracilis relies on the combination of material stiffness adapted for momentum transfer and the antiadhesive properties of the wax crystal surface. The impact-driven oscillation of the N. gracilis lid represents a new kind of rapid plant movement with adaptive function. Our findings establish the existence of a continuum between active and passive trapping mechanisms in carnivorous plants. PMID:26438874
Fadde, Peter J
The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn't get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters' box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures, the cooperating team
Fadde, Peter J.
The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn't get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters' box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures, the cooperating team
In 1907 baseball's promoters decreed that Civil War hero Abner Doubleday created the game in the village of Cooperstown, New York, in 1839. Baseball thus acquired a distinctly rural American origin and a romantic pastoral appeal. Skeptics have since presented irrefutable evidence that America's pastime was neither born in the United States nor was a product of rural life. But in their zeal to debunk the myth of baseball's rural beginnings, historians have fallen prey to what Annales School founder Marc Bloch famously called the "idol of origins," and all but neglected the very real phenomenon of rural baseball itself. The claim that baseball has always been "a city game for city men" does not stand up to empirical scrutiny anymore than the Doubleday myth itself, as this address demonstrates with three case studies -- Cooperstown in the 1830s, Davisville, California, in the 1880s, and Milroy, Minnesota, in the 1950s. Baseball may have been a source of rural nostalgia for city people, but it was the sport of choice for farmers and a powerful cultural agent.
Wiley, Jennifer; George, Tim; Rayner, Keith
Two experiments investigated the effects of domain knowledge on the resolution of ambiguous words with dominant meanings related to baseball. When placed in a sentence context that strongly biased toward the non-baseball meaning (positive evidence), or excluded the baseball meaning (negative evidence), baseball experts had more difficulty than non-experts resolving the ambiguity. Sentence contexts containing positive evidence supported earlier resolution than did the negative evidence condition for both experts and non-experts. These experiments extend prior findings, and can be seen as support for the reordered access model of lexical access, where both prior knowledge and discourse context influence the availability of word meanings.
Zachazewski, James; Silvers, Holly J.; Li, Bernard; Snyder-Mackler, Lynn; Insler, Stephanie; Ahmad, Christopher S.; Mandelbaum, Bert R.
Objectives: The purpose of this study is to test the efficacy of a hamstring injury prevention program designed to address the high incidence of acute and chronic hamstring injuries and re-injuries that occur in the sport of professional baseball. Methods: This was a prospective cluster cohort study assessing the efficacy of an injury prevention intervention designed to address hamstring injury in rookie and professional baseball players participating in Minor and Major League Baseball (N = 213). Each athlete was asked to participate and consented (Johns Hopkins Internal Review Board, Baltimore, Maryland). Those athletes who agreed to participate completed a questionnaire detailing their hamstring injury history. The hamstring injury prevention program was disseminated to each medical staff (team physician, certified athletic trainer and strength and conditioning coach) and they were instructed on how to implement the program. Weekly individual compliance with the program and injury data was collected. At the end of the season, the data were analyzed for program compliance and hamstring (HS) injury rates (both acute and reoccurrence) compared to the control data in the MLB HITS database. All data were stripped of individual and team identifiers prior to analysis. Results: For the major and minor league intervention study, one Major and Minor League organization served as the intervention (INT) team, which encompassed Rookie League, Fall Ball, Class A, AA, AAA and major league rosters (6 total teams). A total of 213 athletes consented to participate: Minor League: N = 173 players and Majors League: N = 40. Weekly compliance, injury incidence and time loss due to injury was compared to the HITS database (age, skill matched control group). The average weighted utilization of the injury prevention program was 25.30 utilizations for the uninjured group compared to 13.53 in the injured group (p=0.09). In the majors, there were 2 HS injuries in the INT vs. 79 in the CON
Lage, Marcos; Ono, Jorge Piazentin; Cervone, Daniel; Chiang, Justin; Dietrich, Carlos; Silva, Claudio T
Major League Baseball (MLB) has a long history of providing detailed, high-quality data, leading to a tremendous surge in sports analytics research in recent years. In 2015, MLB.com released the StatCast spatiotemporal data-tracking system, which has been used in approximately 2,500 games since its inception to capture player and ball locations as well as semantically meaningful game events. This article presents a visualization and analytics infrastructure to help query and facilitate the analysis of this new tracking data. The goal is to go beyond descriptive statistics of individual plays, allowing analysts to study diverse collections of games and game events. The proposed system enables the exploration of the data using a simple querying interface and a set of flexible interactive visualization tools.
Nakata, Hiroki; Sakamoto, Kiwako
The present study investigated the existence of the relative age effect, a biased distribution of birth dates, in Japanese professional baseball players born from 1911 to 1980. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. Thus, athletes were divided into four groups based on their month of birth; quarters Q1 (April-June), Q2 (July-September), Q3 (October-December), and Q4 (January-March of the following year). There were statistically biased distributions of birth dates among players born in the 1940s and subsequent decades (medium effects), and similar (but small) relative age effects were observed among players born in the 1910s, 1920s, and 1930s. The magnitude of the relative age effect changed with time, and socio-cultural factors such as international competition and media coverage may have contributed greatly to this effect.
Ernster, V L; Grady, D G; Greene, J C; Walsh, M; Robertson, P; Daniels, T E; Benowitz, N; Siegel, D; Gerbert, B; Hauck, W W
The effects of smokeless tobacco (ST) use were studied in 1109 members of major and minor league professional baseball teams during spring training in 1988. The prevalence of current ST use was 39%. The median age at initiation among users was 18 years, and the median duration of use was 5 years. Among users, 75% cited a snuff brand as their usual ST product. Oral leukoplakia was present in 46% (196/423) of current-week ST users and 1.4% (7/493) of nonusers (odds ratio, 60; 95% confidence interval, 28 to 130). Prevalence of oral leukoplakia among ST users increased with hours used per day and decreased with time lapsed since last use, and was higher in snuff users than in chewing tobacco users. Of the subjects with oral leukoplakia who underwent punch biopsy, 91 had benign hyperkeratosis and one had mild dysplasia. Overall prevalence of dental caries, gingivitis, and plaque did not differ between ST users and nonusers. In analyses confined to facial surfaces of mandibular incisor teeth, where ST is most commonly used, there were significant increases among users in both gingival recession and attachment loss. Users of ST did not differ from nonusers in blood pressure, pulse, total or high-density lipoprotein cholesterol level, or white blood cell count, but among users high-density lipoprotein cholesterol levels were inversely associated with serum cotinine levels. The major health effects of ST use among professional baseball players are oral leukoplakia and localized periodontal disease. The study population was young, physically fit, and characterized by relatively moderate short-term ST use.
Stephens, Jessica D; Santos, Scott R; Folkerts, Debbie R
Pitcher plant bogs, or carnivorous plant wetlands, have experienced extensive habitat loss and fragmentation throughout the southeastern United States Coastal Plain, resulting in an estimated reduction to <3% of their former range. This situation has lead to increased management attention of these habitats and their carnivorous plant species. However, conservation priorities focus primarily on the plants since little information currently exists on other community members, such as their endemic arthropod biota. Here, we investigated the population structure of one of these, the obligate pitcher plant moth Exyra semicrocea (Lepidoptera: Noctuidae), using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. Examination of 221 individuals from 11 populations across eight southeastern US states identified 51 unique haplotypes. These haplotypes belonged to one of two divergent (∼1.9-3.0%) lineages separated by the Mississippi alluvial plain. Populations of the West Gulf Coastal Plain exhibited significant genetic structure, contrasting with similarly distanced populations east of the Mississippi alluvial plain. In the eastern portion of the Coastal Plain, an apparent transition zone exists between two regionally distinct population groups, with a well-established genetic discontinuity for other organisms coinciding with this zone. The structure of E. semicrocea appears to have been influenced by patchy pitcher plant bog habitats in the West Gulf Coastal Plain as well as impacts of Pleistocene interglacials on the Apalachicola-Chattahoochee-Flint River Basin. These findings, along with potential extirpation of E. semicrocea at four visited, but isolated, sites highlight the need to consider other endemic or associated community members when managing and restoring pitcher plant bog habitats.
Stephens, Jessica D.; Santos, Scott R.; Folkerts, Debbie R.
Pitcher plant bogs, or carnivorous plant wetlands, have experienced extensive habitat loss and fragmentation throughout the southeastern United States Coastal Plain, resulting in an estimated reduction to <3% of their former range. This situation has lead to increased management attention of these habitats and their carnivorous plant species. However, conservation priorities focus primarily on the plants since little information currently exists on other community members, such as their endemic arthropod biota. Here, we investigated the population structure of one of these, the obligate pitcher plant moth Exyra semicrocea (Lepidoptera: Noctuidae), using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. Examination of 221 individuals from 11 populations across eight southeastern US states identified 51 unique haplotypes. These haplotypes belonged to one of two divergent (∼1.9–3.0%) lineages separated by the Mississippi alluvial plain. Populations of the West Gulf Coastal Plain exhibited significant genetic structure, contrasting with similarly distanced populations east of the Mississippi alluvial plain. In the eastern portion of the Coastal Plain, an apparent transition zone exists between two regionally distinct population groups, with a well-established genetic discontinuity for other organisms coinciding with this zone. The structure of E. semicrocea appears to have been influenced by patchy pitcher plant bog habitats in the West Gulf Coastal Plain as well as impacts of Pleistocene interglacials on the Apalachicola-Chattahoochee-Flint River Basin. These findings, along with potential extirpation of E. semicrocea at four visited, but isolated, sites highlight the need to consider other endemic or associated community members when managing and restoring pitcher plant bog habitats. PMID:21829473
Kurata, Kaoruko; Jaffré, Tanguy; Setoguchi, Hiroaki
Among the many species that grow in New Caledonia, the pitcher plant Nepenthes vieillardii (Nepenthaceae) has a high degree of morphological variation. In this study, we present the patterns of genetic differentiation of pitcher plant populations based on chloroplast DNA haplotype analysis using the sequences of five spacers. We analyzed 294 samples from 16 populations covering the entire range of the species, using 4660 bp of sequence. Our analysis identified 17 haplotypes, including one that is widely distributed across the islands, as well as regional and private haplotypes. The greatest haplotype diversity was detected on the eastern coast of the largest island and included several private haplotypes, while haplotype diversity was low in the southern plains region. The parsimony network analysis of the 17 haplotypes suggested that the genetic divergence is the result of long-term isolation of individual populations. Results from a spatial analysis of molecular variance and a cluster analysis suggest that the plants once covered the entire serpentine area of New Caledonia and that subsequent regional fragmentation resulted in the isolation of each population and significantly restricted seed flow. This isolation may have been an important factor in the development of the morphological and genetic variation among pitcher plants in New Caledonia.
Ishikawa, Hideki; Hori, Shingo; Aikawa, Naoki
The Meiji Jingu Baseball Stadium attracts a large number of spectators in the Tokyo metropolitan area. To clarify the demand for medical care at a public ballpark, we analyzed following two types of medical records maintained at the stadium: (1) "Report of Aid": a record of patients visiting the first-aid station in 2003 season and (2) "Report of Accidents": a record of patients referred to clinics/hospitals between 1996 and 2003 season. (1) In 2003, approximately 1,582,000 spectators watched 67 professional baseball games (60 night games). Of the 247 spectators received medical care at the first-aid station (3.7 persons per game, 1/6,405 spectators), 128 (51.8%) had trauma and 109 (44.1%) had illness. The incidence of trauma was relatively higher before the start and near the end of the night games. The risk of becoming sick/wounded per spectator or the number of the sick/wounded per game differed depending on the participating sports teams. (2) Ninety-three spectators referred to clinics/hospitals during the 8-year period from 1996 to 2003, of which 57 were transferred by ambulance. Direct ball injury accounted for 65 (69.9%) cases of trauma, followed by stumbling/falls (18 cases, 19.4%). Twenty patients were diagnosed to have fractures at the clinics/hospitals. Intrinsic cardiopulmonary arrest occurred in one spectator. Trauma due to direct ball injury accounted for the largest number of wounded patients referred to clinics/hospitals. Treatment to patients at the first-aid station in the stadium may optimize the frequency of hospital visits. Records of medical care are effective to analyze the demand for medical preparedness.
Walsh, M.; Ellison, J.; Hilton, J.; Chesney, M.; Ernster, V.
OBJECTIVE—To describe the prevalence, patterns, and correlates of spit (smokeless) tobacco (ST) use in a sample of high school baseball athletes in California. DESIGN—This cross sectional study was a survey of 1226 baseball athletes attending 39 California high schools that were randomly selected from a list of all publicly supported high schools with baseball teams. At a baseball team meeting, athletes who agreed to participate and had parental consent completed the study questionnaire. To enhance the accuracy of self reported ST use status, a saliva sample was collected from each subject. The questionnaires and saliva samples were coded and salivary cotinine assay was performed on a random subsample of 5% of non-users who also were non-smokers. Biochemical assay indicated that 2% tested positive for cotinine inconsistent with self reported ST non-use. RESULTS—Overall, 46% had ever used ST and 15% were current users. Odds ratios and 95% confidence intervals (CI) suggested that, among high school baseball athletes, age, living in a rural area, being white, smoking cigarettes, drinking alcohol, not knowing about the adverse effects of ST, perceiving little personal risk associated with ST use, and believing that friends, role models, teammates, and same age baseball athletes in general used ST, increased the likelihood of being an ST user. CONCLUSION—The findings indicate that considerable experimentation with ST products occurs among high school baseball athletes in California, and many are current users. ST interventions targeting this population are needed to stop the transition from experimental ST use to tobacco dependence. Correlates of ST use for consideration in future intervention studies are identified. Keywords: chewing tobacco; spit tobacco; snuff; smokeless tobacco PMID:10841589
Hill, Stephen E.; Schvaneveldt, Shane J.
This article presents an educational exercise in which statistical process control charts are constructed and used to identify the Steroids Era in American professional baseball. During this period (roughly 1993 until the present), numerous baseball players were alleged or proven to have used banned, performance-enhancing drugs. Also observed…
Bjarkman, Peter C.
Continues the discussion of the contributions of racial and ethnic minorities to baseball history, focusing on African Americans, Hispanic Americans, and Jews. Nonfiction and fiction works dealing with minority groups in baseball are briefly reviewed for their portrayal of the American experience. (SLD)
Havens, Kayri; Jolls, Claudia L.; Marik, Julie E.; Vitt, Pati; McEachern, A. Kathryn; Kind, Darcy
Larinus planus Frabicius (Curculionidae), is a seed-eating weevil that was inadvertently introduced into the US and was subsequently distributed in the US and Canada for the control of noxious thistle species of rangelands. It has been detected recently in the federally threatened Pitcher's thistle (Cirsium pitcheri). We assayed weevil damage in a natural population of Pitcher's thistle at Whitefish Dunes State Park, Door County, WI and quantified the impact on fecundity. We then estimated the impact of this introduced weevil and other emerging threats on two natural, uninvaded populations of Pitcher's thistle for which we have long-term demographic data for 16 yr (Wilderness State Park, Emmet County, MI) and 23 yr (Miller High Dunes, Indiana Dunes National Lakeshore, Porter County, IN). We used transition matrices to determine growth rates and project the potential effects of weevil damage, inbreeding, goldfinch predation, and vegetative succession on Pitcher's thistle population viability. Based on our models, weevil seed predation reduced population growth rate by 10–12%, but this reduction was enough to reduce time to extinction from 24 yr to 13 yr and 8 yr to 5 yr in the MI and IN population, respectively. This impact is particularly severe, given most populations of Pitcher's thistle throughout its range hover near or below replacement. This is the first report of unanticipated ecological impacts from a biocontrol agent on natural populations of Cirsium pitcheri.
It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses. Key pointsBiomechanical analyses including kinematic and kinetic analyses allow for estimation of pitching performance and potential for injury.Some difficulties both theoretic and practical exist for the implementation and interpretation of such analyses.Commonly held opinions of baseball pitching authorities are largely held to concur with biomechanical analyses.Recommendations can be made regarding appropriate pitching and throwing technique in light of these investigations. PMID:24149219
Sasada, Manami; Nakamoto, Hiroki; Ikudome, Sachi; Unenaka, Satoshi; Mori, Shiro
In order to test the theoretical idea that experts rely more on the dorsal stream than the ventral stream during interceptive action for the interception of a moving target, the present study investigates the perception of color (dominant in ventral processing) during interceptive action in fast-ball sports. Twelve college baseball players and 12 non-baseball players performed a coincident-timing task with target color changes (from white to red, blue, or white) at various time points (at 100, 200, or 300 ms before target arrival). In this task, participants swung a bat and/or pressed a button in response to the target's arrival at a prespecified location. Participants were then asked to state the final color of the target. Baseball players, but not non-baseball players, were significantly less proficient at identifying color changes during the bat-swing condition relative to the button-press condition, irrespective of the time points of color change. These results are consistent with the idea that baseball players rely more on the dorsal stream during bat swinging for the interception of a moving target than do novices.
It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses. Key pointsBiomechanical analyses including kinematic and kinetic analyses allow for estimation of pitching performance and potential for injury.Some difficulties both theoretic and practical exist for the implementation and interpretation of such analyses.Commonly held opinions of baseball pitching authorities are largely held to concur with biomechanical analyses.Recommendations can be made regarding appropriate pitching and throwing technique in light of these investigations.
Miller, Thomas E; terHorst, Casey P
Succession is a foundation concept in ecology that describes changes in species composition through time, yet many successional patterns have not been thoroughly investigated. We highlight three hypotheses about succession that are often not clearly stated or tested: (1) individual communities become more stable over time, (2) replicate communities become more similar over time, and (3) diversity peaks at mid-succession. Testing general patterns of succession requires estimates of variation in trajectories within and among replicate communities. We followed replicate aquatic communities found within leaves of purple pitcher plants (Sarracenia purpurea) to test these three hypotheses. We found that stability of individual communities initially decreased, but then increased in older communities. Predation was highest in younger leaves but then declined, while competition was likely strongest in older leaves, as resources declined through time. Higher levels of predation and competition corresponded with periods of higher stability. As predicted, heterogeneity among communities decreased with age, suggesting that communities became more similar over time. Changes in diversity depended on trophic level. The diversity of bacteria slightly declined over time, but the diversity of consumers of bacteria increased linearly and strongly throughout succession. We suggest that studies need to focus on the variety of environmental drivers of succession, which are likely to vary through time and across habitats.
Paisie, Taylor K; Miller, Thomas E; Mason, Olivia U
The aquatic communities found within the water filled leaves of the pitcher plant, Sarracenia purpurea, have a simple trophic structure providing an ideal system to study microscale interactions between protozoan predators and their bacterial prey. In this study, replicate communities were maintained with and without the presence of the bactivorous protozoan, Colpoda steinii, to determine the effects of grazing on microbial communities. Changes in microbial (Archaea and Bacteria) community structure were assessed using iTag sequencing of 16S rRNA genes. The microbial communities were similar with and without the protozoan predator, with>1000 species. Of these species, Archaea were negligible, with Bacteria comprising 99.99% of the microbial community. The Proteobacteria and Bacteroidetes were the most dominant phyla. The addition of a protozoan predator did not have a significant effect on microbial evenness nor richness. However, the presence of the protozoan did cause a significant shift in the relative abundances of a number of bacterial species. This suggested that bactivorous protozoan may target specific bacterial species and/or that certain bacterial species have innate mechanisms by which they evade predators. These findings help to elucidate the effect that trophic structure perturbations have on predator prey interactions in microbial systems.
terHorst, Casey P
Ecologists have long recognized the importance of indirect ecological effects on species abundances, coexistence, and diversity. However, the evolutionary consequences of indirect interactions are rarely considered. Here I conduct selection experiments and examine the evolutionary response of Colpoda sp., a ciliated protozoan, to other members of the inquiline community of purple pitcher plants (Sarracenia purpurea). I measured the evolution of six traits in response to (1) predation by mosquito larvae, (2) competition from other ciliated protozoans, and (3) simultaneous predation and competition. The latter treatment incorporated both direct effects and indirect effects due to interactions between predators and competitors. Population growth rate and cell size evolved in response to direct effects of predators and competitors. However, trait values in the multispecies treatment were similar to those in the monoculture treatment, indicating that direct effects were offset by strong indirect effects on the evolution of traits. For most of the traits measured, indirect effects were opposed to, and often stronger than, direct effects. These indirect effects occurred as a result of behavioral changes of the predator in the presence of competitors and as a result of reduced densities of competitors in the presence of predators. Incorporating indirect effects provides a more realistic description of how species evolve in complex natural communities.
Hsu, Chiao-Peng; Lin, Yu-Min; Chen, Po-Yu
Carnivorous pitcher plants of the genus Nepenthes have evolved specialized leaves fulfilling the multi-functions of attracting, capturing, retaining and digesting the prey, mostly arthropods. Different capturing mechanisms have been proposed and discussed in previous works. The most important capture mechanism is the unique super-hydrophilic surface properties of the peristome. The combination of a hierarchical surface structure and nectar secretions results in an exceptional water-lubricated trapping system. Anisotropic and unidirectional wettability is attributed to the ridge-like surface and epidermal folding. The three-dimensional plate-like wax crystals in the hydrophobic waxy zone can further prevent the prey from escaping. The captured prey are then digested in the hydrophilic digestive zone. The hybrid species Nepenthes × Miranda was investigated in this study. The surface morphology and hierarchical microstructure were characterized by scanning electron microscope. Contact angle measurement and wetting efficiency tests were performed to determine the wettability of the peristome under fresh, nectar-free and sucrose-coated conditions with controlled temperature and humidity. The results showed that sucrose-coated peristome surfaces possess the best wetting efficiency. The structure-property-function relationship and the capturing mechanism of Nepenthes were elucidated, which could further lead to the design and synthesis of novel bio-inspired surfaces and potential applications.
Eilenberg, Haviva; Pnini-Cohen, Smadar; Rahamim, Yocheved; Sionov, Edward; Segal, Esther; Carmeli, Shmuel; Zilberstein, Aviah
Nepenthes spp. are carnivorous plants that have developed insect capturing traps, evolved by specific modification of the leaf tips, and are able to utilize insect degradation products as nutritional precursors. A chitin-induced antifungal ability, based on the production and secretion to the trap liquid of droserone and 5-O-methyldroserone, is described here. Such specific secretion uniquely occurred when chitin injection was used as the eliciting agent and probably reflects a certain kind of defence mechanism that has been evolved for protecting the carnivory-based provision of nutritional precursors. The pitcher liquid containing droserone and 5-O-methyldroserone at 3:1 or 4:1 molar ratio, as well as the purified naphthoquinones, exerted an antifungal effect on a wide range of plant and human fungal pathogens. When tested against Candida and Aspergillus spp., the concentrations required for achieving inhibitory and fungicidal effects were significantly lower than those causing cytotoxicity in cells of the human embryonic kidney cell line, 293T. These naturally secreted 1,4-naphthoquinone derivatives, that are assumed to act via semiquinone enhancement of free radical production, may offer a new lead to develop alternative antifungal drugs with reduced selectable pressure for potentially evolved resistance. PMID:20018905
At Reynolds numbers above about 105 the aerodynamic drag force on a sphere drops sharply as the flow begins to become turbulent in the boundary layer. For baseballs, this ``drag crisis'' may occur at speeds which are typical for pitched or batted balls. The effects of the drag reduction on the behavior of both pitched and batted balls is significant, and may explain several features of the game of baseball which previously have been unexplained or attributed to other causes. In particular, the drag reduction may help to explain why pitched fastballs appear to rise, why pitched curve balls appear to drop sharply, and why home run production has increased since the introduction of the alleged ``lively ball.'' Calculations suggest that aerodynamic forces are as important a factor in fastpitch softball as in baseball, and that they are a critical factor in a number of other ball games.
Anecdotal evidence from players and coaches indicates that cognitive processing (e.g., expectations about the upcoming pitch) plays an important role in successful baseball batting, yet this aspect of hitting has not been investigated in detail. The present study provides experimental evidence that prior expectations significantly influence the timing of a baseball swing. A two-state Markov model was used to predict the effects of pitch sequence and pitch count on batting performance. The model is a hitting strategy of switching between expectancy states using a simple set of transition rules. In a simulated batting experiment, the model provided a good fit to the hitting performance of 6 experienced college baseball players, and the estimated model parameters were highly correlated with playing level.
Morohoshi, Tomohiro; Oikawa, Manabu; Sato, Shoko; Kikuchi, Noriko; Kato, Norihiro; Ikeda, Tsukasa
Members of the genus Nepenthes are carnivorous plants that use the pitfall method of insect capture as a supplementary nutritional source. We extracted metagenomic DNA from the microbial community found in the pitcher fluid of Nepenthes and constructed a plasmid-based metagenomic library. An activity-based screening method enabled the isolation of two lipase genes, lip1 and lip2. Both Lip1 and Lip2 belong to a novel family or subfamily of lipases and show lipase activities in acidic conditions, such as those found in pitcher fluid. This study was conducted under the assumption that the secreted Lip1 and Lip2 were capable of enzymatic activity in the acidic pitcher fluid.
Song, Alex; Severini, Thomas; Allada, Ravi
Laboratory studies have demonstrated that circadian clocks align physiology and behavior to 24-h environmental cycles. Examination of athletic performance has been used to discern the functions of these clocks in humans outside of controlled settings. Here, we examined the effects of jet lag, that is, travel that shifts the alignment of 24-h environmental cycles relative to the endogenous circadian clock, on specific performance metrics in Major League Baseball. Accounting for potential differences in home and away performance, travel direction, and team confounding variables, we observed that jet-lag effects were largely evident after eastward travel with very limited effects after westward travel, consistent with the >24-h period length of the human circadian clock. Surprisingly, we found that jet lag impaired major parameters of home-team offensive performance, for example, slugging percentage, but did not similarly affect away-team offensive performance. On the other hand, jet lag impacted both home and away defensive performance. Remarkably, the vast majority of these effects for both home and away teams could be explained by a single measure, home runs allowed. Rather than uniform effects, these results reveal surprisingly specific effects of circadian misalignment on athletic performance under natural conditions.
Song, Alex; Severini, Thomas; Allada, Ravi
Laboratory studies have demonstrated that circadian clocks align physiology and behavior to 24-h environmental cycles. Examination of athletic performance has been used to discern the functions of these clocks in humans outside of controlled settings. Here, we examined the effects of jet lag, that is, travel that shifts the alignment of 24-h environmental cycles relative to the endogenous circadian clock, on specific performance metrics in Major League Baseball. Accounting for potential differences in home and away performance, travel direction, and team confounding variables, we observed that jet-lag effects were largely evident after eastward travel with very limited effects after westward travel, consistent with the >24-h period length of the human circadian clock. Surprisingly, we found that jet lag impaired major parameters of home-team offensive performance, for example, slugging percentage, but did not similarly affect away-team offensive performance. On the other hand, jet lag impacted both home and away defensive performance. Remarkably, the vast majority of these effects for both home and away teams could be explained by a single measure, home runs allowed. Rather than uniform effects, these results reveal surprisingly specific effects of circadian misalignment on athletic performance under natural conditions. PMID:28115724
Takeuchi, Yayoi; Salcher, Michaela M; Ushio, Masayuki; Shimizu-Inatsugi, Rie; Kobayashi, Masaki J; Diway, Bibian; von Mering, Christian; Pernthaler, Jakob; Shimizu, Kentaro K
The genus Nepenthes, a carnivorous plant, has a pitcher to trap insects and digest them in the contained fluid to gain nutrient. A distinctive character of the pitcher fluid is the digestive enzyme activity that may be derived from plants and dwelling microbes. However, little is known about in situ digestive enzymes in the fluid. Here we examined the pitcher fluid from four species of Nepenthes. High bacterial density was observed within the fluids, ranging from 7×10(6) to 2.2×10(8) cells ml(-1). We measured the activity of three common enzymes in the fluid: acid phosphatases, β-D-glucosidases, and β-D-glucosaminidases. All the tested enzymes detected in the liquid of all the pitcher species showed activity that considerably exceeded that observed in aquatic environments such as freshwater, seawater, and sediment. Our results indicate that high enzyme activity within a pitcher could assist in the rapid decomposition of prey to maximize efficient nutrient use. In addition, we filtered the fluid to distinguish between dissolved enzyme activity and particle-bound activity. As a result, filtration treatment significantly decreased the activity in all enzymes, while pH value and Nepenthes species did not affect the enzyme activity. It suggested that enzymes bound to bacteria and other organic particles also would significantly contribute to the total enzyme activity of the fluid. Since organic particles are themselves usually colonized by attached and highly active bacteria, it is possible that microbe-derived enzymes also play an important role in nutrient recycling within the fluid and affect the metabolism of the Nepenthes pitcher plant.
Tran, Phuong M; Dahl, John L
Several fast- to intermediate-growing, acid-fast, scotochromogenic bacteria were isolated from Sarracenia purpurea pitcher waters in Minnesota sphagnum peat bogs. Two strains (DL734T and DL739T) were among these isolates. On the basis of 16S rRNA gene sequences, the phylogenetic positions of both strains is in the genus Mycobacterium with no obvious relation to any characterized type strains of mycobacteria. Phenotypic characterization revealed that neither strain was similar to the type strains of known species of the genus Mycobacterium in the collective properties of growth, pigmentation or fatty acid composition. Strain DL734T grew at temperatures between 28 and 32 °C, was positive for 3-day arylsulfatase production, and was negative for Tween 80 hydrolysis, urease and nitrate reduction. Strain DL739T grew at temperatures between 28 and 37 °C, and was positive for Tween 80 hydrolysis, urea, nitrate reduction and 3-day arylsulfatase production. Both strains were catalase-negative while only DL739T grew with 5 % NaCl. Fatty acid methyl ester profiles were unique for each strain. DL739T showed an ability to survive at 8 °C with little to no cellular replication and is thus considered to be psychrotolerant. Therefore, strains DL734T and DL739T represent two novel species of the genus Mycobacterium with the proposed names Mycobacterium sarraceniae sp. nov. and Mycobacterium helvum sp. nov., respectively. The type strains are DL734T (=JCM 30395T=NCCB 100519T) and DL739T (=JCM 30396T=NCCB 100520T), respectively.
Chin, Lijin; Chung, Arthur YC; Clarke, Charles
Pitcher plants of the genus Nepenthes capture a wide range of arthropod prey for nutritional benefit, using complex combinations of visual and olfactory signals and gravity-driven pitfall trapping mechanisms. In many localities throughout Southeast Asia, several Nepenthes different species occur in mixed populations. Often, the species present at any given location have strongly divergent trap structures and preliminary surveys indicate that different species trap different combinations of arthropod prey, even when growing at the same locality. On this basis, it has been proposed that co-existing Nepenthes species may be engaged in niche segregation with regards to arthropod prey, avoiding direct competition with congeners by deploying traps that have modifications that enable them to target specific prey types. We examined prey capture among 3 multi-species Nepenthes populations in Borneo, finding that co-existing Nepenthes species do capture different combinations of prey, but that significant interspecific variations in arthropod prey combinations can often be detected only at sub-ordinal taxonomic ranks. In all lowland Nepenthes species examined, the dominant prey taxon is Formicidae, but montane Nepenthes trap few (or no) ants and 2 of the 3 species studied have evolved to target alternative sources of nutrition, such as tree shrew feces. Using similarity and null model analyses, we detected evidence for niche segregation with regards to formicid prey among 5 lowland, sympatric Nepenthes species in Sarawak. However, we were unable to determine whether these results provide support for the niche segregation hypothesis, or whether they simply reflect unquantified variation in heterogeneous habitats and/or ant communities in the study sites. These findings are used to propose improvements to the design of field experiments that seek to test hypotheses about targeted prey capture patterns in Nepenthes. PMID:24481246
Dahm, Kevin; Newell, James
Reports on a course at Rowan University, based on the economic design of a baseball stadium, that offers an introduction to multidisciplinary engineering design linked with formal training in technical communication. Addresses four pedagogical goals: (1) developing public speaking skills in a realistic, business setting; (2) giving students…
Spragg, Carolyn; Noble, Larry
Six female intercollegiate varsity softball players and six male intercollegiate varsity baseball players were filmed from overhead while batting a wiffle ball off a batting tee at hip height. Movements of the hips, trunk, upper body segments, and bat were analyzed. Group comparisons indicated that males had higher peak linear and, angular…
Inoue, Takuya; Uematsu, Yuko; Saito, Hideo
Movies can be used to analyze a player's performance and improve his/her skills. In the case of baseball, the pitching is recorded by using a high-speed camera, and the recorded images are used to improve the pitching skills of the players. In this paper, we present a method for estimating of the rotational velocity of a baseball on the basis of movies recorded by high-speed cameras. Unlike in the previous methods, we consider the original seam pattern of the ball seen in the input movie and identify the corresponding image from a database of images by adopting the parametric eigenspace method. These database images are CG Images. The ball's posture can be determined on the basis of the rotational parameters. In the proposed method, the symmetric property of the ball is also taken into consideration, and the time continuity is used to determine the ball's posture. In the experiments, we use the proposed method to estimate the rotational velocity of a baseball on the basis of real movies and movies consisting of CG images of the baseball. The results of both the experiments prove that our method can be used to estimate the ball's rotation accurately.
Bat/ball contact produces visual (the ball leaving the bat), auditory (the "crack" of the bat), and tactile (bat vibration) feedback about the success of the swing. We used a batting simulation to investigate how college baseball players use visual, tactile, and auditory feedback. In Experiment 1, swing accuracy (i.e., the lateral separation…
Hagerman, Frederick C.; And Others
The article describes the development of a comprehensive conditioning and education program to ensure total fitness (including aerobic) in professional baseball players on and off season, noting that standard training keeps them fit in every way except aerobically. The program helped them improve playing performance and develop a healthy…
Growing student interest in sports provides geography teachers with a special opportunity to make connections between it and fundamental concepts in the discipline. This article examines the structure, arrangement, relationships, and distinctions among minor league baseball franchise locations, stadia, and team names, and presents examples of…
Kimiecik, Jay C.
The author uses his father's autobiographical writings about the small-town, baseball experiences of his youth as background for discussing the significant cultural shifts that have dramatically changed the nature of the game from a free-play experience for neighborhood kids to an organized youth-league sport. In contrast to his father's day, the…
Abel, Ernest L.; Kruger, Michael L.
We tested McCann's precocity-longevity hypothesis, which proposes that early career achievement is related to premature death, for Major League baseball players (N = 3,760). Age at debut was the definition for precocity. We controlled for possible artifacts of life expectancy selection, the "healthy worker" effect, player position, and body-mass…
Laliberte, David J.
Far more than just recreation, baseball offers social, cultural, and political insights into history. For teachers, the goals of this article are threefold. First, this narrative is designed to provide the introductory content knowledge needed to develop a colorful lecture, structure a spirited discussion, or create a student project on the topic.…
Hepler, Teri J.; Feltz, Deborah L.
The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and…
Hums, Mary A.; Sutton, William A.
A survey of 152 women administrators in professional baseball indicated that their greatest challenges and least-enjoyable job aspects were mostly gender-related issues: the need to gain respect and credibility, be taken seriously, overcome stereotypes, and deal with sexism and sexual harassment. Nearly half felt their compensation was less than…
Holahan, William L.; Kroncke, Charles O.
For some time now, it has been the posture of major league baseball that taxpayers should bear some or all of the cost of new stadiums. They argue that the community will benefit both economically and psychologically from such an investment. A stadium, they claim, will bring new jobs, increased land values, enhanced tax collections, and perhaps…
For two weeks every June, the College World Series showcases one of the National Collegiate Athletic Association's (NCAA's) most popular sports. More than 300,000 fans flock to picturesque Rosenblatt Stadium, in Omaha, with millions more tuning in on ESPN. Ticket sales, which in recent years topped $9-million, make baseball the NCAA's…
Bell, Benjamin; Zirkel-Rubin, Jessica
Introduces an instructional framework called Virtual Galleries that situates learning within an exhibit development context in which a student assumes the role of a museum curator. Describes the Abner project, a Web-based application for teaching middle- and high-school students about United States history through professional baseball, and…
The ability to inhibit an ongoing action in response to a signal from the environment is important for many perceptual-motor actions. This paper examines a particular example of this behavior: attempting to inhibit or "check" a swing in baseball batting. A model of motor inhibition in batting is proposed. In the model there are three different…
Satler, Jordan D; Carstens, Bryan C
Comparative phylogeographic investigations have identified congruent phylogeographic breaks in co-distributed species in nearly every region of the world. The qualitative assessments of phylogeographic patterns traditionally used to identify such breaks, however, are limited because they rely on identifying monophyletic groups across species and do not account for coalescent stochasticity. Only long-standing phylogeographic breaks are likely to be obvious; many species could have had a concerted response to more recent landscape events, yet possess subtle signs of phylogeographic congruence because ancestral polymorphism has not completely sorted. Here, we introduce Phylogeographic Concordance Factors (PCFs), a novel method for quantifying phylogeographic congruence across species. We apply this method to the Sarracenia alata pitcher plant system, a carnivorous plant with a diverse array of commensal organisms. We explore whether a group of ecologically associated arthropods have co-diversified with the host pitcher plant, and identify if there is a positive correlation between ecological interaction and PCFs. Results demonstrate that multiple arthropods share congruent phylogeographic breaks with S. alata, and provide evidence that the level of ecological association can be used to predict the degree of similarity in the phylogeographic pattern. This study outlines an approach for quantifying phylogeographic congruence, a central concept in biogeographic research.
Siragusa, Alex J; Swenson, Janice E; Casamatta, Dale A
The culturable microbial community within the pitcher fluid of 93 Sarracenia minor carnivorous plants was examined over a 2-year study. Many aspects of the plant/bacterial/insect interaction within the pitcher fluid are minimally understood because the bacterial taxa present in these pitchers have not been identified. Thirteen isolates were characterized by 16S rDNA sequencing and subsequent phylogenetic analysis. The Proteobacteria were the most abundant taxa and included representatives from Serratia, Achromobacter, and Pantoea. The Actinobacteria Micrococcus was also abundant while Bacillus, Lactococcus, Chryseobacterium, and Rhodococcus were infrequently encountered. Several isolates conformed to species identifiers (>98% rDNA gene sequence similarity) including Serratia marcescens (isolates found in 27.5% of pitchers), Achromobacter xylosoxidans (37.6%), Micrococcus luteus (40.9%), Bacillus cereus (isolates found in 10.2%), Bacillus thuringiensis (5.4%), Lactococcus lactis (17.2%), and Rhodococcus equi (2.2%). Species-area curves suggest that sampling efforts were sufficient to recover a representative culturable bacterial community. The bacteria present represent a diverse community probably as a result of introduction by insect vectors, but the ecological significance remains under explored.
Dahm, Diane L; Curriero, Frank C; Camp, Christopher L; Brophy, Robert H; Leo, Tony; Meister, Keith; Paletta, George A; Steubs, John A; Mandelbaum, Bert R; Pollack, Keshia M
Few studies have explored the frequency and impact of lower extremity injuries, such as those to the knee, among professional baseball players. The purpose of this study was to detail the epidemiology of knee injuries in Major League Baseball (MLB) and Minor League Baseball (MiLB) players during the 2011-2014 seasons. It was hypothesized that knee injuries are a common occurrence in these athletes, and represent a significant source of time away from play. The MLB Health and Injury Tracking System database was searched to identify all patients diagnosed with knee injuries during the 2011-2014 seasons. All injuries that occurred during the preseason, regular season, and postseason that resulted in time away from play were included. Injury data analyzed included total number of knee injuries, specific diagnoses, injury mechanisms, locations, player positions, and time lost. Descriptive statistics were conducted and injury rates per athlete-exposures were calculated. During the 2011-2014 seasons, a total of 2171 knee injuries occurred in MLB and MiLB players, representing 6.5% of all injuries in professional baseball. The knee injury rate across both the MLB and MiLB was 1.2 per 1000 athlete-exposures. The mean number of days missed per injury across both leagues was 16.2 with a total of 30,449 days of missed play amongst all athletes over the 4 seasons. Injuries to the knee were the fifth most common cause of missed time in all of baseball, and the fourth most common reason for missed games in the MLB alone. Approximately 12% of all injuries required surgical intervention. The most common mechanism of injury was noncontact (44%), and base runners were injured more frequently than any other position (24%). The infield (30%) and home plate (23%) were the most common locations in which injuries occurred. These data can be utilized for targeted injury prevention initiatives.
Severson, H; Klein, K; Lichtensein, E; Kaufman, N; Orleans, C
Objective: The use of smokeless tobacco (ST) (snuff and chewing tobacco) has long been associated with baseball in the USA. This article reviews six years of survey data from major and minor league baseball players to evaluate trends in tobacco use and quitting patterns over time in order to gain insight into the effects of past interventions and to document continued intervention needs. Method: Surveys were distributed by athletic trainers to major and minor league professional baseball players during spring training session in the six years from 1998 to 2003. The surveys were anonymous and identified only by team, level of league, and other self reported demographic data. Results: ST use among professional baseball players remains much higher than among young males in the general population, and use is most prevalent among white non-Hispanic players. There was a significant decrease in ST use among minor league players from 1998 to 2003, with seven day self reported use declining from 31.7% in 1998 to 24.8% in 2003. No significant year to year changes were observed for major league players. Major league players' self reported past week use rates, estimated at 35.9% in 1998 and at 36% in 2003, were consistently higher than those of minor league players. Self reported prevalence of past month cigarette and cigar smoking was much lower than ST use for both major and minor league players. Conclusions: Six years of survey data confirm a continuing high use of ST among professional baseball players. Results suggest that the effects of the broad spectrum ST control efforts launched over the past decade may have been stronger among minor than major league players. Stronger policy interventions at the major league level and multi-level efforts, including programmes to increase the use of effective quitting aids and assistance, at both levels of play are needed. Future research is needed to further clarify changes in ST practices among professional players and set policy
... teens, biceps tendonitis is usually an overuse injury. Baseball pitchers, swimmers, tennis players, and people who have ... But if you swim or play tennis or baseball, that might not be an option! If your ...
Higuchi, Takatoshi; Nagami, Tomoyuki; Morohoshi, Jun; Nakata, Hiroki; Kanosue, Kazuyuki
The present study investigated bat control of skilled baseball batters during tee batting, faced with an intentional change in target position. Twelve, skilled, male baseball players (M age = 24 yr., SD = 4) participated in the study. Participants were instructed to hit a baseball off a tee 0.8 m from the ground (Hitting condition), and also to deliberately swing just above the ball (Air Swing condition). The task for the participants was to perform, in alternate order, 15 swings at a real baseball on a stationary tee and 15 swings at an imaginary ball that was said to be on top of the real baseball. The participants were instructed to hit the ball toward center field just as they would hit in a game. While most participants could hit the real ball in the sweet area of the bat, only one participant did so in the Air Swing condition. Average distances from the center of the sweet area to ball center at the moment of ball-bat contact in the Air Swing condition (85 mm) were significantly greater than the distance in the Hitting condition (38 mm). The larger error in hitting an imaginary ball in the sweet area could be due to perceptual changes following the batter's altered focus, expectation of a lack of contact, and/or lack of feedback from the swing. It was suggested that baseball batters should be aware of the possible error in hitting accurately when they intentionally shifted the target.
Emerson, Kevin J; Dake, Sabrina J; Bradshaw, William E; Holzapfel, Christina M
For over 70 years, researchers have debated whether the ability to use day length as a cue for the timing of seasonal events (photoperiodism) is related to the endogenous circadian clock that regulates the timing of daily events. Models of photoperiodism include two components: (1) a photoperiodic timer that measures the length of the day, and (2) a photoperiodic counter that elicits the downstream photoperiodic response after a threshold number of days has been counted. Herein, we show that there is no geographical pattern of genetic association between the expression of the circadian clock and the photoperiodic timer or counter. We conclude that the photoperiodic timer and counter have evolved independently of the circadian clock in the pitcher-plant mosquito Wyeomyia smithii and hence, the evolutionary modification of photoperiodism throughout the range of W. smithii has not been causally mediated by a corresponding evolution of the circadian clock.
Fast, Avital; Thomas, Mark A
Dropped head syndrome (DHS) is a well-recognized condition characterized by gradual sagging of the head. At the extreme, the condition may lead to a "chin on chest deformity" where the chin rests on the chest wall and the patient is unable to look straight ahead. Dropped head syndrome tends to develop in patients with severe weakness of the neck extensors. Various neuromuscular disorders and surgical procedures may compromise the stability of the cervical spine and lead to this disorder. The condition may severely compromise the patient's quality of life and result in significant disability. A simple device-the "baseball cap orthosis"-was developed to help patients maintain their head in the upright position. Two patients with DHS who were provided with the baseball cap orthosis are presented.
Goldschmied, Nadav; Harris, Michael; Vira, Damien; Kowalczyk, Jason
The purpose of this investigation was to test whether the performance of the home run hitters in Major League Baseball adhered to predictions of Drive Theory. 24 baseball players who have hit at least 505 home runs were included in the sample. Their performance was assessed around the time in which they reached a significant home run career milestone, operationalized as either 500 or 600 home runs, or surpassing the league's home run record. As predicted, the players were found to require significantly more at-bats to complete the 5 home runs before the milestone, when stress was assumed to be mounting, than the 5 home runs after the milestone. In contrast, those players who reached the personal landmark from 1988 (the suspected commencement of the so-called "Steroid Era") onwards required the same number of at-bats before and after the milestone.
STS-95 Payload Specialist John H. Glenn Jr. (left) greets baseball legend Ted Williams at a reception at the Double Tree Oceanfront Hotel following a parade down State Road A1A in nearby Cocoa Beach. Organizers of the parade included the Cocoa Beach Area Chamber of Commerce, the Brevard County Tourist Development Council, and the cities of Cape Canaveral and Cocoa Beach. The parade is reminiscent of those held after missions during the Mercury Program.
Noguchi, Takanori; Demura, Shinichi; Takahashi, Kenji; Demura, Gou; Mori, Yasunori
We examined the differences in muscle power between the dominant and nondominant upper limbs of 33 healthy, right-handed, university baseball players (mean age, 20.4 ± 1.1 years) with an average baseball experience >11 years. After measuring maximal voluntary contraction (MVC) of hand grip, elbow flexion, and shoulder internal rotation in both upper limbs, the muscle power of each joint was measured at 40%, 50%, and 60% MVC. No significant differences were observed in the main factors affecting MVC and elbow flexion power loads between dominant and nondominant upper limbs. For handgrip power, load factors at 40% MVC in the dominant hand were lower than those at 60% MVC in the same hand and those at 50% and 60% MVC in the nondominant hand. Significant differences were observed in shoulder internal rotation power between dominant and nondominant upper limbs, with the dominant limb having greater power at all loads. Correlations between muscle power of both upper limbs for handgrip and elbow flexion were significant and moderately high at all loads. For shoulder internal rotation power, the degree of correlation was significant and moderately high at 40% MVC but low to moderate at 50% and 60% MVC. Therefore, baseball players have marked lateral dominance in shoulder internal rotation power unlike handgrip and elbow flexion power, although the relationship between shoulder internal rotation muscle powers of both upper limbs becomes lower with increasing load. The dominance of muscle power of each joint varied even in the same upper limb. It is thus beneficial for baseball players to train with even loads on both arms or adopt simultaneous workout of both arms after adjusting for strength differences.
Yamashiro, Koya; Sato, Daisuke; Onishi, Hideaki; Sugawara, Kazuhiro; Nakazawa, Sho; Shimojo, Hirofumi; Akatsuka, Kosuke; Nakata, Hiroki; Maruyama, Atsuo
Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4) in 12 baseball players (baseball group) and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group). The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs) were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT). Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes.
Coleman, Struan H; Mayer, Stephanie W; Tyson, Jared J; Pollack, Keshia M; Curriero, Frank C
Injuries of the hip and groin among professional baseball players can result in a significant number of disabled list days. The epidemiology of these injuries has not been delineated. The purpose of this study is to describe the incidence, mechanism, type, and rehabilitation course of hip and groin injuries among Major League Baseball (MLB) and Minor League Baseball (MiLB) players. The MLB injury database for hip and groin injuries from 2011-2014 was analyzed. Occurrence of injuries was assessed based on level of play, field location, activity during which the injury occurred, mechanism of injury, and days missed. The treatment was recorded as nonoperative or surgical. The subsequent rehabilitation and return to play were recorded. Chi-square tests were used to test the hypothesis of equal proportions between the various categories of hip and groin characteristics. From 2011-2014, 1823 hip and groin injuries occurred among MLB and MiLB players, which accounted for approximately 5% of all injuries. Of these, 1514 (83%) occurred among MiLB players and 309 (17%) among MLB players; 96% of injuries were extra-articular. Among all players, a noncontact mechanism during defensive fielding was the most common activity causing injury (74%), and infielders experienced the most hip and groin injuries (34%). The majority of extra-articular injuries were treated nonoperatively (96.2%), resulting in an average of 12 days missed. Intra-articular pathology more commonly required surgery, and resulted in an average of 123 days missed. Hip and groin injuries can be debilitating and result in a significant number of days missed. Intra-articular pathology and athletic pubalgia were usually treated surgically, while the majority of extra-articular hip injuries were treated successfully with nonoperative modalities. Correct diagnosis and appropriate treatment can lead to a high rate of return to play for professional baseball players with injuries to the hip and groin.
McIntosh, A; Janda, D
Background: Protective helmets in sport are important for reducing the risk of head and facial injury. In cricket and other sports with projectiles, national test standards control the minimum helmet performance. However, there are few field data showing if helmets are effective in reducing head injury. Objectives: (a) To examine the performance of cricket helmets in laboratory tests; (b) to examine performance with regard to test standards, game hazards, and helmet construction; (c) to compare and contrast these findings with baseball and ice hockey helmets. Methods: Impact tests were conducted on a selection of helmet models: five cricket, two baseball, and two ice hockey. Ball to helmet impacts at speeds of 19, 27, 36, and 45 m/s were produced using an air cannon and a Hybrid III dummy headform and neck unit. Free fall drop tests with a rigid headform on to a selection of anvils (flat rigid, flat deformable, and hemispherical rigid) were conducted. Resultant headform acceleration was measured and compared between tests. Results: At the lower speed impacts, all helmets produced a good reduction in headform acceleration, and thus injury risk. At the higher speed impacts, the effectiveness was less. For example, the mean maximum headform accelerations for all cricket helmets at each speed were: 67, 160, 316, and 438 g for 19, 27, 36, and 45 m/s ball speeds respectively. Drop tests on to a hemispherical anvil produced the highest accelerations. The variation in performance increased as the magnitude of the impact energy increased, in both types of testing. Conclusions: The test method used for baseball helmets in which the projectile is fired at the helmet may be superior to helmet drop tests. Cricket helmet performance is satisfactory for low speed impacts, but not for impacts at higher, more realistic, speeds. Baseball and ice hockey helmets offer slightly better relative and absolute performance at the 27 m/s ball and puck impacts. PMID:12893718
Yamashiro, Koya; Sato, Daisuke; Onishi, Hideaki; Sugawara, Kazuhiro; Nakazawa, Sho; Shimojo, Hirofumi; Akatsuka, Kosuke; Nakata, Hiroki; Maruyama, Atsuo
Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4) in 12 baseball players (baseball group) and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group). The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs) were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT). Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes. PMID:26600391
Yamashiro, Koya; Sato, Daisuke; Onishi, Hideaki; Yoshida, Takuya; Horiuchi, Yoko; Nakazawa, Sho; Maruyama, Atsuo
Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in short-latency somatosensory-evoked potentials (SEPs). The aim of this study is to clarify whether specific training in athletes affects the long-latency SEPs related to information processing of stimulation. The long-latency SEPs P100 and N140 were recorded at midline cortical electrode positions (Fz, Cz, and Pz) in response to stimulation of the index finger of the dominant hand in fifteen baseball players (baseball group) and in fifteen athletes in sports such as swimming, track and field events, and soccer (sports group) that do not require fine somatosensory discrimination or motor control of the hand. The long-latency SEPs were measured under a passive condition (no response required) and a reaction time (RT) condition in which subjects were instructed to rapidly push a button in response to stimulus presentation. The peak P100 and peak N140 latencies and RT were significantly shorter in the baseball group than the sports group. Moreover, there were significant positive correlations between RT and both the peak P100 and the peak N140 latencies. Specific athletic training regimens that involve the hand may induce neuroplastic alterations in the cortical hand representation areas playing a vital role in rapid sensory processing and initiation of motor responses.
Whiteley, Rod; Adams, Roger; Ginn, Karen; Nicholson, Leslie
Humeral torsion is thought to be beneficial for throwing. To examine this hypothesis, the throwing and non-throwing arms of 84 Masters baseball players over 35 years of age were measured for humeral torsion, and the highest playing level they achieved and their playing history were recorded. Regression analyses were used to obtain predictors of the highest playing level achieved, throwing arm humeral torsion, and side-to-side difference in humeral torsion. Equations accounting for 36%, 46%, and 12% of the variance respectively were produced. Achieving representative level playing status was associated with the number of seasons played under 16 years of age and having greater throwing arm humeral retrotorsion. Throwing arm humeral retrotorsion was associated with non-throwing arm humeral retrotorsion and an increased number of seasons played before the age of 16 years. A model in which repeated throwing develops an adaptive unilateral bone torsion along with growth in baseball expertise is proposed. Thus dominant arm humeral retrotorsion is a predictor of highest baseball playing level achieved, which in turn is influenced by genetic endowment (as seen in the torsion of the non-throwing arm) and amount of throwing activity, particularly prior to the age of 16.
Bray, Steven R; Obara, Jeff; Kwan, Matt
In baseball and softball, there is a rule that allows the home team to have the last at-bat and thus the final opportunity to win the game. However, in tournament play, this rule is often set aside and, instead, batting order is decided by other means (e.g. tournament rules, the flip of a coin). The purpose of this study was to examine the impact of the batting last rule on game outcome in NCAA men's regional tournament baseball. It was hypothesized that host (i.e. home) teams would win a greater percentage of the games in which they batted last compared with when they batted first. This hypothesis was not supported. Closer examination of the last inning of play showed home teams were no more likely to have won the game during their last bat than visitors playing other visitors. The results suggest that the batting last rule contributes minimally, if at all, to home advantage in NCAA tournament baseball.
Scrutinizes the author's response to a seemingly stereotypical male narrative written by a student fitting the disruptive macho male stereotype. Examines how teachers respond to stereotypical male narratives of conquest and individualist triumph, and whether their responses to such essays are not conditioned by their responses to the authors. (TB)
Miyashita, Koji; Urabe, Yukio; Kobayashi, Hirokazu; Yokoe, Kiyoshi; Koshida, Sentaro; Kawamura, Morio; Ida, Kunio
The objective of the present study was to examine whether the passive range of shoulder external rotation (ER), the maximum shoulder external rotation angle (MER) during throwing, and the ratio of MER to ER are related to the incidence of the elbow injury. A mixed design with one between-factor (a history of the elbow injury) and two within-factors (ER and MER) was used to analyze the difference between baseball players with and without a history of medial elbow pain. Twenty high school baseball players who had experienced the medial elbow pain within the previous month but who were not experiencing the pain on the day of the experiment were recruited (elbow-injured group). Another twenty baseball players who had never experienced the medial elbow pain were also used for testing (control group). MER during throwing, ER, and the ratio of MER to ER were obtained in both of the group. A Mann-Whitney test was used for the group comparison (p < 0.05). The ratio of MER to ER was significantly greater in the elbow-injured group (1.52 ± 0.19) than that in the control group (1.33 ± 0.23) (p = 0.008). On the other hand, there was no statistical significance in MER and ER between two groups. The findings of the study indicate that MER/ER relation could be associated with the incidence of the elbow injury in baseball players. Key pointsIt is accepted that the greatest elbow valgus stress appears at the position of shoulder maximum external rotation (MER) in the acceleration phase of the throwing movement. As a consequence, shoulders with restricted range of motion of external rotation (ER) compensate with a valgus stress on their elbow joints.In this study, we evaluated the relation between MER and ER of shoulder in players with/without elbow injuries.The result of this study demonstrated that the elbow injured group showed significantly greater MER/ER relation than the control group.The current finding suggests that great MER combined with the ROM restriction may be one of
Rasic, Gordana; Keyghobadi, Nusha
The spatial scale at which samples are collected and analysed influences the inferences that can be drawn from landscape genetic studies. We examined genetic structure and its landscape correlates in the pitcher plant midge, Metriocnemus knabi, an inhabitant of the purple pitcher plant, Sarracenia purpurea, across several spatial scales that are naturally delimited by the midge's habitat (leaf, plant, cluster of plants, bog and system of bogs). We analysed 11 microsatellite loci in 710 M. knabi larvae from two systems of bogs in Algonquin Provincial Park (Canada) and tested the hypotheses that variables related to habitat structure are associated with genetic differentiation in this midge. Up to 54% of variation in individual-based genetic distances at several scales was explained by broadscale landscape variables of bog size, pitcher plant density within bogs and connectivity of pitcher plant clusters. Our results indicate that oviposition behaviour of females at fine scales, as inferred from the spatial locations of full-sib larvae, and spatially limited gene flow at broad scales represent the important processes underlying observed genetic patterns in M. knabi. Broadscale landscape features (bog size and plant density) appear to influence oviposition behaviour of midges, which in turn influences the patterns of genetic differentiation observed at both fine and broad scales. Thus, we inferred linkages among genetic patterns, landscape patterns and ecological processes across spatial scales in M. knabi. Our results reinforce the value of exploring such links simultaneously across multiple spatial scales and landscapes when investigating genetic diversity within a species.
Muraskin, Jordan; Sherwin, Jason; Sajda, Paul
Given a decision that requires less than half a second for evaluating the characteristics of the incoming pitch and generating a motor response, hitting a baseball potentially requires unique perception-action coupling to achieve high performance. We designed a rapid perceptual decision-making experiment modeled as a Go/No-Go task yet tailored to reflect a real scenario confronted by a baseball hitter. For groups of experts (Division I baseball players) and novices (non-players), we recorded electroencephalography (EEG) while they performed the task. We analyzed evoked EEG single-trial variability, contingent negative variation (CNV), and pre-stimulus alpha power with respect to the expert vs. novice groups. We found strong evidence for differences in inhibitory processes between the two groups, specifically differential activity in supplementary motor areas (SMA), indicative of enhanced inhibitory control in the expert (baseball player) group. We also found selective activity in the fusiform gyrus (FG) and orbital gyrus in the expert group, suggesting an enhanced perception-action coupling in baseball players that differentiates them from matched controls. In sum, our results show that EEG correlates of decision formation can be used to identify neural markers of high-performance athletes.
Muraskin, Jordan; Sherwin, Jason; Sajda, Paul
Given a decision that requires less than half a second for evaluating the characteristics of the incoming pitch and generating a motor response, hitting a baseball potentially requires unique perception-action coupling to achieve high performance. We designed a rapid perceptual decision making experiment modeled as a Go/No-Go task, yet tailored to reflect a real scenario confronted by a baseball hitter. For groups of experts (Division I baseball players) and novices (non-players) we recorded electroencephalography (EEG) while they performed the task. We analyzed evoked EEG single-trial variability, contingent negative variation (CNV), and pre-stimulus alpha power with respect to the expert vs. novice groups. We found strong evidence for differences in inhibitory processes between the two groups, specifically differential activity in supplementary motor areas (SMA), indicative of enhanced inhibitory control in the expert (baseball player) group. We also found selective activity in the fusiform gyrus (FG) and orbital gyrus in the expert group, suggesting an enhanced perception-action coupling in baseball players that differentiates them from matched controls. In sum, our results show that EEG correlates of decision formation can be used to identify neural markers of high-performance athletes. PMID:26299795
Furushima, Kozo; Itoh, Yoshiyasu; Mitsui, Yasuhiro; Kusano, Hiroshi
Objectives: Many baseball players with UCL injuries have avulsed persistent fragments by throwing disorder in the youth. The presence of fragments results in discontinuity of the medial elbow joint support structures; therefore, a ligament with fragments is considered more fragile than the normal ligament. This study compared three types (fragment, malunion, and normal) of throwing-related UCL injuries and prospectively examined the risk of surgical treatment. Methods: The total subjects were 439 baseball players (age 14-30 years; mean age, 17.5 years) diagnosed with UCL injuries at our hospital between November 2009 and June 2013. At the time of the initial examination, the medial epicondyle was assessed on plain frontal radiographs with the elbow flexed at 45°. Based on this assessment, subjects were divided into three groups: group with persistent fragments (fragment [F] group), group with complete union following avulsion fracture (malunion [M] group), and a group with no history of avulsion fracture (normal [N] group). Each patient’s ability to return to playing baseball was assessed after at least 3 months of systematic rehabilitation. Subjects who failed to comply with rehabilitation, played only recreationally, or with pain in sites other than the elbow were excluded. In this series, 220 cases were left for investigation. The Conway-Jobe scale was used as a standard to assess the return to playing after conservative therapy; subjects with excellent or good ratings were deemed able to return to playing baseball, whereas those with fair or poor ratings were deemed unable to return to playing baseball. The return rates were calculated for the F, M, and N groups respectively. The Magnetic resonance (MR) images consisted of three slices along the long axis of the anterior oblique ligament; these images were used to classify injuries as severe or mild, which were then compared with each other. SPSS 20.0 was used to perform the statistical analysis. Results: A
Development - adolescent; Growth and development - adolescent ... During adolescence, children develop the ability to: Understand abstract ideas. These include grasping higher math concepts, and developing moral ...
Romero, Anthony C; Fulkerson, Eric; Rockman, Caron B; Bosco, Joe; Rosen, Jeffrey
Traumatic STA aneurysm is a rare complication of facial trauma occuring typically in young men. We present the case of a minor league baseball player who developed 2 pseudoaneurysms after being struck by a baseball and review all cases associated with sports activities. Reports associated with sports activities are increasing and may represent an increasing incidence. The team physician should suspect this condition when a player presents with a new temporal mass after facial trauma. Diagnosis is typically made on history and physical examination, but can be confirmed by duplex ultrasound. Definitive treatment is surgical resection of the aneurysm after proximal and distal ligation of the vessel.
Examined extent to which Scottish adolescents (N=40) were influenced by negative images of adolescence present in the culture, investigating self-images by means of Q sort. Eleven factors emerged from analysis, six of which met criterion that distinguishes common factors. Little evidence was found to suggest that adolescents were influenced by…
Workers carefully align a mounting bracket attached to an F/A-18 Hornet aircraft with the top of a pedestal in front of the municipal baseball stadium in the city of Lancaster, California. The Blue-and-white twin-jet aircraft, formerly flown as a safety chase and support aircraft by NASA's Dryden Flight Research Center, Edwards, California, was loaned to the city for display following its recent retirement. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.
An F/A-18 Hornet aircraft formerly flown by NASA's Dryden Flight Research Center, Edwards, California, is sandwiched between two groups of workers as they mount it atop a pedestal at the municipal baseball stadium in the city of Lancaster, California. NASA Dryden had flown the blue-and-white twin-jet as a safety chase and support aircraft for about nine years prior to its recent retirement. The aircraft is now in loan to the city for public display. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.
As news media and city officials watch from the balcony of the city baseball stadium in Lancaster, California, a crane gently positions an F/A-18 Hornet aircraft for mounting on a steel pedestal. The F/A-18 was recently retired by NASA's Dryden Flight Research Center, Edwards, California, after being flown as a safety chase and support aircraft over the past nine years. The aircraft is now mounted nose skyward on the 28-foot-tall pedestal in front of the Lancaster Municipal Stadium, know as 'The Hangar.' The stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.
A large crane gingerly lowers an F/A-18 Hornet aircraft onto a 28-foot-tall pedestal in front of the municipal baseball stadium in the city of Lancaster, California. The blue-and-white F/A-18 was recently loaned to the city by NASA's Dryden Flight Research Center, Edwards, California. NASA Dryden had flown the twin-jet aircraft as a safety chase and support aircraft over the past nine years. The stadium, known as 'The Hangar,' is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.
Ishisaki, Kana; Arai, Sachiko; Hamada, Tatsuro; Honda, Yuji
A class III chitinase belonging to the GH18 family from Nepenthes alata (NaCHIT3) was expressed in Escherichia coli. The enzyme exhibited hydrolytic activity toward colloidal chitin, ethylene glycol chitin, and (GlcNAc)(n) (n=5 and 6). The enzyme hydrolyzed the fourth glycosidic linkage from the non-reducing end of (GlcNAc)(6). The anomeric form of the products indicated it was a retaining enzyme. The colloidal chitin hydrolytic reaction displayed high activity between pH 3.9 and 6.9, but the pH optimum of the (GlcNAc)(6) hydrolytic reaction was 3.9 at 37 °C. The optimal temperature for activity was 65 °C in 50 mM sodium acetate buffer (pH 3.9). The pH optima of NaCHIT3 and NaCHIT1 might be related to their roles in chitin degradation in the pitcher fluid.
Wang, Peng; Zhang, Dun; Lu, Zhou
Marine biofouling, caused by the adhesion of microorganism, is a worldwide problem in marine systems. In this research work, slippery liquid-infused porous surface (SLIPS), inspired by Nepenthes pitcher plant, was constructed over aluminum for marine anti-biofouling application. The as-fabricated SLIPS was characterized with SEM, AFM, and contact angle meter. Its anti-biofouling performance was evaluated with settlement experiment of a typical marine biofouling organism Chlorella vulgaris in both static and dynamic conditions. The effect of solid substrate micro-structure on anti-biofouling property of SLIPS was studied. It was suggested that the micro-structure with low length scale and high degree of regularity should be considered for designing stable SLIPS with exceptional anti-biofouling property. The liquid-like property is proven to be the main contributor for the exceptional anti-biofouling performance of SLIPS in both static and dynamic conditions. The low roughness, which facilitates removing the settled C. vulgaris under shear force, is also a main contributor for the anti-biofouling performance of SLIPS in dynamic condition.
Merz, Clayton; Catchen, Julian M; Hanson-Smith, Victor; Emerson, Kevin J; Bradshaw, William E; Holzapfel, Christina M
Herein we tested the repeatability of phylogenetic inference based on high throughput sequencing by increased taxon sampling using our previously published techniques in the pitcher-plant mosquito, Wyeomyia smithii in North America. We sampled 25 natural populations drawn from different localities nearby 21 previous collection localities and used these new data to construct a second, independent phylogeny, expressly to test the reproducibility of phylogenetic patterns. Comparison of trees between the two data sets based on both maximum parsimony and maximum likelihood with Bayesian posterior probabilities showed close correspondence in the grouping of the most southern populations into clear clades. However, discrepancies emerged, particularly in the middle of W. smithii's current range near the previous maximum extent of the Laurentide Ice Sheet, especially concerning the most recent common ancestor to mountain and northern populations. Combining all 46 populations from both studies into a single maximum parsimony tree and taking into account the post-glacial historical biogeography of associated flora provided an improved picture of W. smithii's range expansion in North America. In a more general sense, we propose that extensive taxon sampling, especially in areas of known geological disruption is key to a comprehensive approach to phylogenetics that leads to biologically meaningful phylogenetic inference.
Merz, Clayton; Catchen, Julian M.; Hanson-Smith, Victor; Emerson, Kevin J.; Bradshaw, William E.; Holzapfel, Christina M.
Herein we tested the repeatability of phylogenetic inference based on high throughput sequencing by increased taxon sampling using our previously published techniques in the pitcher-plant mosquito, Wyeomyia smithii in North America. We sampled 25 natural populations drawn from different localities nearby 21 previous collection localities and used these new data to construct a second, independent phylogeny, expressly to test the reproducibility of phylogenetic patterns. Comparison of trees between the two data sets based on both maximum parsimony and maximum likelihood with Bayesian posterior probabilities showed close correspondence in the grouping of the most southern populations into clear clades. However, discrepancies emerged, particularly in the middle of W. smithii's current range near the previous maximum extent of the Laurentide Ice Sheet, especially concerning the most recent common ancestor to mountain and northern populations. Combining all 46 populations from both studies into a single maximum parsimony tree and taking into account the post-glacial historical biogeography of associated flora provided an improved picture of W. smithii's range expansion in North America. In a more general sense, we propose that extensive taxon sampling, especially in areas of known geological disruption is key to a comprehensive approach to phylogenetics that leads to biologically meaningful phylogenetic inference. PMID:24039746
Zhang, Junping; Wu, Lei; Li, Bucheng; Li, Lingxiao; Seeger, Stefan; Wang, Aiqin
The newly developed Nepenthes pitcher (NP)-inspired slippery surfaces, formed by immobilizing fluoroliquids on lotus leaf (LL)-inspired superoleophobic surfaces, are of great general interest, whereas there are many interesting phenomena and fundamental scientific issues remaining to be unveiled. Here we present our findings of the effects of evaporation of the fluoroliquid, an inevitable process in most cases, -induced transition from NP-inspired to LL-inspired surfaces on the wettability, transparency, and self-cleaning property of the surfaces. The transition is controlled by regulating the evaporation temperature of the model fluoroliquid, Krytox100. The evaporation of Krytox100 has great a influence on the wettability, transparency, and self-cleaning property. An intermediate "sticky" state is observed in the transition process. We believe that our findings in the transition process are helpful in understanding the similarities and differences between the NP-inspired and LL-inspired surfaces and in designing new bioinspired antiwetting surfaces and exploring their potential applications.
Pawlak, Roman; Malinauskas, Brenda; Rivera, David
Objective: To assess factors important to college baseball players regarding intention to eat a healthful diet within the Theory of Planned Behavior. Design: A survey based on the Theory of Planned Behavior was administered during the 2006 summer league season from 5 of the Northern Division teams of the Coastal Plain League. Participants: Male…
The booklet discusses sports adaptations for unilateral and bilateral upper limb amputees. Designs for adapted equipment are illustrated and information on adaptations are described for archery (including an archery release aid and a stationary bow holder); badminton (serving tray); baseball/softball (adaptations for catching, throwing, and…
Gawrysiak, Edward Joseph; Cooper, Joseph N.; Hawkins, Billy
The purpose of this study was to examine the impact of baseball participation on the educational experiences of black student-athletes at two Historically Black Colleges and Universities (HBCUs) in the southeastern United States (US). HBCUs were selected for this study because of the limited amount of research on student-athletes at these…
Bjarkman, Peter C.
Continues a series by presenting a representative list of fiction and nonfiction titles on the topic of baseball and cultural diversity. Sources and novels on African-American, Latin American, and Jewish ballplayers are listed, for a total of 246 references. (SLD)
MacMahon, Clare; Starkes, Janet L
Baseball umpires, players, and control participants with no baseball experience were asked to call balls and strikes for video clips. In a basic judgement task, umpires and players were significantly better at calling pitches than controls. In a direct information task, borderline pitches were presented following clips of definite balls and definite strikes. Participants called target pitches closer to the strike end of the scale when viewed after definite balls than when they followed definite strikes. Similarly, when borderline pitches were shown in different pitch counts, participants called pitches more towards the strike end of the scale when there were three balls in the count (3-0, 3-2). These findings indicate that the standard for evaluation changes based on the context in which stimuli are processed. Moreover, the strength of the contextual factors is illustrated in that the effects were shown in observers with and without experience in the task. Overall, however, umpires had a greater tendency to call strikes, indicating that they may use a norm of "hastening the game".
Oliver, Gretchen Dawn; Weimar, Wendi
Lower to upper extremity sequencing of energy and force is linked by virtue of the scapula. It was the purpose of this study to examine the relationship between passive hip rotational range of motion and scapular kinematics during baseball pitching. Nineteen youth baseball players (11.3 ± 0.6 years; 151.8 ± 8.8 cm; 45.9 ± 10.9 kg) with no history of injury participated. Bilateral hip passive rotational range of motion was measured pre and post pitching a simulated game. Scapular kinematics at the position of shoulder maximum external rotation during the pitching cycle were recorded in the first and last innings of the simulated game. Post simulated game, stance leg hip passive internal rotation revealed significant correlations (r = -0.57, P = 0.01) with scapula anterior/posterior tilt at the pitching event of maximum humeral external rotation. The current study reveals that pitching a simulated game results in alterations throughout the kinetic chain. Specifically, this study strengthens the notion that lumbopelvic-hip complex parameters play a significant role in shoulder motion. With this link identified, it is suggested that clinical focus be directed musculature about the lumbopelvic-hip complex as well as muscles that work to stabilise the scapula during dynamic movement.
Crotin, Ryan L; Forsythe, Charles M; Bhan, Shivam; Karakolis, Thomas
Major League Baseball (MLB) players have not been longitudinally examined for changes in physical size. Height, weight, and body mass indices (BMIs) were examined among offensive league leaders (OLL) and MLB reference cohorts at 1970, 1990, and 2010. Anthropometric values were expected to increase successively, where OLL were expected to be larger at each respective time point. A Mixed Model analysis of variance (p ≤ 0.05) examined anthropometric differences over time within and between groups. Mass and BMI increased over successive years with the largest effect seen between 1990 and 2010 (p < 0.001). A significant height reduction was shown for OLL from 1970 to 1990 (p ≤ 0.05), being the only significant decrease in physical size; yet, leaders were heavier and taller compared with the MLB reference population (p < 0.014). Results show that physical size has evolved in MLB, with the OLL being the largest players shown at each year in succession. Professional baseball scouts may have been influenced by greater offensive prowess shown by larger athletes; yet, increased secular anthropometrics must also be factored in greater heights, weights, BMIs shown over time in MLB. It is possible that greater participation in strength and conditioning programs at an earlier age, advances in sport nutrition, and potential abuse of anabolic drugs are factors perpetuating growth rates at present.
Brown, Bryan A.; Kloser, Matt
This project explores conceptual continuity as a framework for understanding students' native ways of understanding and describing. Conceptual continuity suggests that the relationship between the use of words in one genre and the scientific genre can exist at varying levels of association. This perspective can reveal the varied relationships between ideas explained in everyday or vernacular genres and their association to scientific explanations. We conducted a 2-year study involving 15 high school baseball players' understanding of the physics involved in baseball. First, we conducted a quantitative assessment of their science understanding by administering a test prior to season one (2006) and season two (2007). Second, we examined the types of linguistic resources students used to explain their understanding. Third, we revisited our data by using conceptual continuity to identify similarities between students' conceptual understanding in the informal contexts and their similarities to canonical scientific ideas. The results indicated students' performance on the multiple-choice questions suggested no significant improvement. The qualitative analyses revealed that students were able to accurately explain different components of the idea by using a diversity of scientific and non-scientific genres. These results call attention to the need to reconstruct our vision of science learning to include a more language sensitive approach to teaching and learning.
Pollack, Keshia M; D'Angelo, John; Green, Gary; Conte, Stan; Fealy, Stephen; Marinak, Chris; McFarland, Edward; Curriero, Frank C
In 2010, Major League Baseball and the Major League Baseball Players Association reached an agreement regarding the development and implementation of an electronic medical record system and a new league-wide injury surveillance system. The systems were developed to create a more efficient method to track medical histories of players longitudinally as they move across Major and Minor league affiliates, as well as to identify and monitor injury trends in the sport, identify areas of specific concern, and conduct epidemiologic research to better optimize player health and safety. The resulting injury surveillance system, the Health and Injury Tracking System (HITS), is a robust system that includes all players from the both the Major and Minor Leagues. HITS also allows for data linkage with other player- and game-level data to inform the development of injury prevention policies and programs. In the present article, we document the development and implementation of HITS; describe its utility for epidemiologic research; illustrate the potential analytic strength of the surveillance system and its ability to inform policy change; and note the potential for this new surveillance system to advance the field of sports injury epidemiology.
Chalmers, Peter Nissen; Erickson, Brandon J.; Sgroi, Terrance; Vignona, Peter; Lesniak, Matthew; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.
Objectives: Background: Injuries of the adolescent shoulder and elbow are common in baseball pitchers. Fatigue has been demonstrated to be a risk factor for injury. Purpose: To determine if shoulder and elbow kinematics, pitching velocity, accuracy, and pain change during a simulated full baseball game in adolescent pitchers. Methods: Methods: Adolescent pitchers between the ages of 13-16 were recruited to throw a 90 pitch simulated game. Shoulder range of motion was assessed before and after the game. Velocity and accuracy were measured for every pitch and every 15th pitch was videotaped from two orthogonal views in high definition at 240 Hz. Quantitative and qualitative mechanics were measured from these videos. Perceived fatigue and pain were assessed after each inning using the visual analog scale. Data was statistically analyzed using a repeated-measures analysis of variance. Results: Results: Twenty-eight elite adolescent pitchers were included. These pitchers, on average, were 14.6±0.9 years old (mean ± standard deviation), had been pitching for 6.3±1.7 years, and threw 94±58 pitches per week. Our experimental model functioned as expected in that pitchers became progressively more fatigued and painful and pitched with a lower velocity as pitch number increased (p<0.001, 0.001, and <0.001 respectively). Knee flexion at ball release progressively increased with pitch number (p=0.008). Hip and shoulder separation significantly decreased as pitch number increased, from 90%±40% at pitch 15 to 40%±50% at pitch 90 (p0.271 in all cases, 91% power for elbow flexion at ball release). External rotation and total range of motion in the pitching shoulder significantly increased post-pitching (p=0.007 and 0.047 respectively). Conclusion: Conclusion: As pitchers progress through a simulated game they throw lower velocity pitches and become fatigued and painful. Core and leg musculature becomes fatigued before upper extremity kinematics change. Based upon these
Kneitel, Jamie M
Trade-offs among species' ecological interactions is a pervasive explanation for species coexistence. The traits associated with trade-offs are typically measured to mechanistically explain species coexistence at a single spatial scale. However, species potentially interact at multiple scales and this may be reflected in the traits among coexisting species. I quantified species' ecological traits associated with the trade-offs expected at both local (competitive ability and predator tolerance) and regional (competitive ability and colonization rate) community scales. The most common species (four protozoa and a rotifer) from the middle trophic level of a pitcher plant (Sarracenia purpurea) inquiline community were used to link species traits to previously observed patterns of species diversity and abundance. Traits associated with trade-offs (competitive ability, predator tolerance, and colonization rate) and other ecological traits (size, growth rate, and carrying capacity) were measured for each of the focal species. Traits were correlated with one another with a negative relationship indicative of a trade-off. Protozoan and rotifer species exhibited a negative relationship between competitive ability and predator tolerance, indicative of coexistence at the local community scale. There was no relationship between competitive ability and colonization rate. Size, growth rate, and carrying capacity were correlated with each other and the trade-off traits: Size was related to both competitive ability and predator tolerance, but growth rate and carrying capacity were correlated with predator tolerance. When partial correlations were conducted controlling for size, growth rate and carrying capacity, the trade-offs largely disappeared. These results imply that body size is the trait that provides the basis for ecological interactions and trade-offs. Altogether, this study showed that the examination of species' traits in the context of coexistence at different scales
Lee, Bobby Jean S.; Garrison, J. Craig; Conway, John E.; Pollard, Kalyssa; Aryal, Subhash
Background: Humeral retrotorsion has been investigated in relation to shoulder range of motion (ROM) in healthy baseball players. Currently, there is limited information on the osseous anatomy and development of ulnar collateral ligament (UCL) tears. Purpose: To determine the relationship between humeral retrotorsion and shoulder ROM in baseball players with a UCL tear. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Fifty-four baseball players (mean age, 18.5 ± 2.0 years) with a UCL tear volunteered for this study. Participants were measured bilaterally for shoulder internal (IR) and external rotation (ER) ROM and humeral retrotorsion. Differences between sides (involved to uninvolved) were used to calculate the glenohumeral internal rotation deficit (GIRD), external rotation ROM difference (ERDiff), total rotational motion difference (TRM), and humeral retrotorsion difference (HTDiff). A multivariate regression analysis was performed with GIRD, ERDiff, and TRM regressing on HTDiff. Univariate analysis was performed to further evaluate the effect of the predictors on each outcome separately. To control for the effect of age, weight, duration of symptoms, and years of experience, the variables were included as covariates. An a priori level was set at P < .05. Results: There was a statistically significant relationship between the GIRD, ERDiff, and TRM results compared with HTDiff (P = .003). Independent analysis revealed a statistically significant relationship between GIRD and HTDiff (P = .004) and between ERDiff and HTDiff (P = .003) but no significant relationship between TRM and HTDiff (P = .999). After adjusting for age, weight, duration of symptoms, years of experience, dominant arm, and position, a significant relationship was found between GIRD and HTDiff (P = .05) and between ERDiff and HTDiff (P = .01). No significant relationship was found between TRM and HTDiff (P = .54). Adjusted univariate regression analysis determined that
Borg, John P.; Morrissey, Michael P.
In this work, we characterize the lift and lateral forces on a two-seam versus four-seam knuckleball and measure the viscous shear stress. We believe these measurements to be the first reported for slowly rotating baseballs. Our findings indicate the seam acts to either delay or advance separation depending upon the ball angle; these results are supported with flow visualization. The combined effect produces significant lift and lateral forces that can rapidly change as the ball rotates. Furthermore, we found the shear stress to be asymmetric which can result in significant in-flight torque. Together, asymmetries in force and shear stress produce the complicated flight trajectories that can confound the hapless batter.
Hepler, Teri J; Feltz, Deborah L
The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performzed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and decision accuracy. Path analyses examined the relationships between self-efficacy, residualized past performance, and current performance. The results indicated that self-efficacy was a significant and consistent predictor of decision speed (eight of nine trials), but not decision accuracy (four of nine trials). It was also found that experience does not have a meaningful effect on the relationship between self-efficacy and decision-making performance in sport.
While workers on the ground steady the craft with guy ropes, workers atop a high-lift truck align the mounting plates as an F/A-18 Hornet airplane formerly flown by NASA's Dryden Flight Research Center is mounted on a 28-foot-tall pedestal in front of the municipal baseball stadium in the city of Lancaster, California. The aircraft was loaned to the city for pulbic display after its recent retirement by Dryden, which is located at nearby Edwards, California. The blue-and-white twin-jet aircraft was flown as a safety chase and support aircraft by NASA Dryden for about nine years before being retired. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.
I describe some of the information processing that batters and fielders use to hit and field in baseball. The decision to hit the fast ball must be made using information from the first 15 feet of the ball's travel and the batter might as well not scan the last half of the flight. The procedures an outfielder uses to field a fly ball, adopted instinctively by 9 year old Little Leaguers, follows from mechanisms designed for the tracking of prey by predator and the avoidance of predators by prey. To this we add the utility of the acoustics of the bat-ball collision for balls hit directly at outfielders, and strategies for the avoidance of errors on ground balls to infielders.
Pope, Devin; Simonsohn, Uri
Where do people's reference points come from? We conjectured that round numbers in performance scales act as reference points and that individuals exert effort to perform just above rather than just below such numbers. In Study 1, we found that professional baseball players modify their behavior as the season is about to end, seeking to finish with a batting average just above rather than below .300. In Study 2, we found that high school students are more likely to retake the SAT after obtaining a score just below rather than above a round number. In Study 3, we conducted an experiment employing hypothetical scenarios and found that participants reported a greater desire to exert more effort when their performance was just short of rather than just above a round number.
Recent studies have found little empirical evidence to suggest that National Basketball Association (NBA) and Major League Baseball (MLB) players have hot streaks. This has led some to suggest that hot hands do not exist and that offensive and defensive strategies adjusting to perceived hot hands are suboptimal. We study the MLB's Home Run Derby and the NBA's 3-point Shootout. When there is no defense, extended time between shots has been removed, and shot or swing selection is constant, we find evidence that player performance is nonstationary. Our results are consistent with beliefs long held by players, coaches, and fans, research on the importance of self-efficacy in sports, and studies that support the existence of hot streaks in sports with no or limited defense.
Gorb, Elena; Kastner, Victoria; Peressadko, Andrei; Arzt, Eduard; Gaume, Laurence; Rowe, Nick; Gorb, Stanislav
Carnivorous plants of the genus Nepenthes grow in nutrient-poor habitats and have evolved specialised trapping organs, known as pitchers. These are composed of different surface zones serving the functions of attraction, capture and digestion of insects, which represent a main source of nitrogen. To investigate the role of the glandular digestive zone in the trapping mechanism of the pitcher, structural, mechanical and physico-chemical studies were applied to N. ventrata and combined with insect behavioural experiments. It was found that the glandular surface is microscopically rough since it is regularly structured with multicellular glands situated in epidermal depressions. The presence of downward-directed 'hoods' over the upper part of glands and sloped depressions in the proximal direction of the pitcher causes a marked anisotropy of the surface. The glandular zone surface is composed of relatively stiff material (Young's modulus, 637.19+/-213.44 kPa). It is not homogeneous, in terms of adhesive properties, and contains numerous areas without adhesion as well as adhesive areas differing greatly in tenacity values (range, 1.39-28.24 kPa). The surface is readily wettable with water (contact angle, 31.9-36.0 degrees C) and has a high surface free energy (56.84-61.93 mN m(-1)) with a relatively high polar component (33.09-52.70 mN m(-1)). To examine the effect of the glandular secretion on attachment systems of insects having hairy and smooth adhesive pads, forces generated on different surfaces by Calliphora vicina flies and Pyrrhocoris apterus bugs, respectively, were measured. Flies attached equally well to both fresh and air-dried glandular surfaces whereas bugs generated a significantly lower force on the fresh glandular surface compared with the air-dried one. It is assumed that the contribution of the glandular surface to insect retention, due to its effect on insect attachment, differs depending on insect weight and the type of insect attachment system
Muraskin, Jordan; Dodhia, Sonam; Lieberman, Gregory; Garcia, Javier O; Verstynen, Timothy; Vettel, Jean M; Sherwin, Jason; Sajda, Paul
Post-task resting state dynamics can be viewed as a task-driven state where behavioral performance is improved through endogenous, non-explicit learning. Tasks that have intrinsic value for individuals are hypothesized to produce post-task resting state dynamics that promote learning. We measured simultaneous fMRI/EEG and DTI in Division-1 collegiate baseball players and compared to a group of controls, examining differences in both functional and structural connectivity. Participants performed a surrogate baseball pitch Go/No-Go task before a resting state scan, and we compared post-task resting state connectivity using a seed-based analysis from the supplementary motor area (SMA), an area whose activity discriminated players and controls in our previous results using this task. Although both groups were equally trained on the task, the experts showed differential activity in their post-task resting state consistent with motor learning. Specifically, we found (1) differences in bilateral SMA-L Insula functional connectivity between experts and controls that may reflect group differences in motor learning, (2) differences in BOLD-alpha oscillation correlations between groups suggests variability in modulatory attention in the post-task state, and (3) group differences between BOLD-beta oscillations that may indicate cognitive processing of motor inhibition. Structural connectivity analysis identified group differences in portions of the functionally derived network, suggesting that functional differences may also partially arise from variability in the underlying white matter pathways. Generally, we find that brain dynamics in the post-task resting state differ as a function of subject expertise and potentially result from differences in both functional and structural connectivity. Hum Brain Mapp 37:4454-4471, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
Frantz, Travis L; Ruiz, Matthew D
Debate exists between the benefits and effectiveness of a dynamic warm-up vs. a static warm-up. This study was conducted to compare dynamic and static warm-ups on lower body explosiveness as measured by stationary vertical jump (VJ) and standing long jump (LJ) among collegiate baseball players. Participants (n = 17; age = 19.59 ± 1.37 years) progressed through 3 different warm-ups on weekly testing dates over a 7-week period. After the warm-up routines, participants were measured for VJ height and LJ distance in centimeters. The mean jump heights for VJ were 66.49 ± 8.28 cm for dynamic, 61.42 ± 7.51 cm for static, and 62.72 ± 7.84 cm for the control condition. The mean jump distances for LJ were 231.99 ± 20.69 cm for dynamic, 219.69 ± 20.96 cm for static, and 226.46 ± 20.60 cm for the control. Results indicated that the participants jumped significantly higher in both experimental conditions while under the influence of the dynamic warm-up (VJ-F = 22.08; df = 1.33, 21.345; p < 0.00 and LJ-F = 32.20; df = 2, 32; p < 0.01). Additional LJ analysis determined that individuals jumped significantly further after no warm-up compared to after a static warm-up (-6.78, p < 0.05). Lower body explosiveness is critical in baseball and many other sports as well. The results show that dynamic warm-up increases both VJ height and LJ distance. Specifically, these findings indicate that athletes could gain nearly 2 in. on his or her vertical jump by simply switching from a static warm-up routine to a dynamic routine.
Dodhia, Sonam; Lieberman, Gregory; Garcia, Javier O.; Verstynen, Timothy; Vettel, Jean M.; Sherwin, Jason
Abstract Post‐task resting state dynamics can be viewed as a task‐driven state where behavioral performance is improved through endogenous, non‐explicit learning. Tasks that have intrinsic value for individuals are hypothesized to produce post‐task resting state dynamics that promote learning. We measured simultaneous fMRI/EEG and DTI in Division‐1 collegiate baseball players and compared to a group of controls, examining differences in both functional and structural connectivity. Participants performed a surrogate baseball pitch Go/No‐Go task before a resting state scan, and we compared post‐task resting state connectivity using a seed‐based analysis from the supplementary motor area (SMA), an area whose activity discriminated players and controls in our previous results using this task. Although both groups were equally trained on the task, the experts showed differential activity in their post‐task resting state consistent with motor learning. Specifically, we found (1) differences in bilateral SMA–L Insula functional connectivity between experts and controls that may reflect group differences in motor learning, (2) differences in BOLD‐alpha oscillation correlations between groups suggests variability in modulatory attention in the post‐task state, and (3) group differences between BOLD‐beta oscillations that may indicate cognitive processing of motor inhibition. Structural connectivity analysis identified group differences in portions of the functionally derived network, suggesting that functional differences may also partially arise from variability in the underlying white matter pathways. Generally, we find that brain dynamics in the post‐task resting state differ as a function of subject expertise and potentially result from differences in both functional and structural connectivity. Hum Brain Mapp 37:4454–4471, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27448098
Clark, Joseph F.; Ellis, James K.; Bench, Johnny; Khoury, Jane; Graman, Pat
Purpose Baseball requires an incredible amount of visual acuity and eye-hand coordination, especially for the batters. The learning objective of this work is to observe that traditional vision training as part of injury prevention or conditioning can be added to a team's training schedule to improve some performance parameters such as batting and hitting. Methods All players for the 2010 to 2011 season underwent normal preseason physicals and baseline testing that is standard for the University of Cincinnati Athletics Department. Standard vision training exercises were implemented 6 weeks before the start of the season. Results are reported as compared to the 2009 to 2010 season. Pre season conditioning was followed by a maintenance program during the season of vision training. Results The University of Cincinnati team batting average increased from 0.251 in 2010 to 0.285 in 2011 and the slugging percentage increased by 0.033. The rest of the Big East's slugging percentage fell over that same time frame 0.082. This produces a difference of 0.115 with 95% confidence interval (0.024, 0.206). As with the batting average, the change for University of Cincinnati is significantly different from the rest of the Big East (p = 0.02). Essentially all batting parameters improved by 10% or more. Similar differences were seen when restricting the analysis to games within the Big East conference. Conclusion Vision training can combine traditional and technological methodologies to train the athletes' eyes and improve batting. Vision training as part of conditioning or injury prevention can be applied and may improve batting performance in college baseball players. High performance vision training can be instituted in the pre-season and maintained throughout the season to improve batting parameters. PMID:22276103
Golub, Ivan J; Garcia, Roberto A; Wittig, James C
A 15-year-old boy presented with a mass in his right arm after suffering a minor injury playing baseball. He had been diagnosed with a hematoma. There was no other outstanding medical/surgical history. Magnetic resonance images showed a heterogeneous mass arising from the brachialis muscle that mainly enhanced peripherally with extremely scant internal nodular enhancement. Core needle biopsy cells were positive for CD31 and CD34, markers for atypical endothelial cells, as well as MIB-1 and p53. The final diagnosis was an angiosarcoma of the brachialis muscle. Pediatric angiosarcoma, particularly within deep tissue, is exceedingly rare. Histological and immunohistochemical modalities led to the diagnosis. Magnetic resonance images suggested a mass with a large cystic/hemorrhagic space that could have been misconstrued as a hematoma had there been absolutely no nodular or septal enhancement. The patient underwent neoadjuvant chemotherapy and radiation before undergoing limb-sparing surgery that included resection of the mass with the brachialis muscle and short head of the biceps muscle. Neoadjuvant treatment was deemed successful due to a drastic reduction in the size of the tumor and 95% tumor necrosis. The patient was disease free 2 years postoperatively. There had been no local/systemic recurrences. He was pain free, had normal elbow function, and had returned to playing baseball. It is important to be extremely suspicious when a patient presents with a hemorrhagic, painless, enlarging mass after sustaining minor trauma. A careful and meticulous biopsy must be completed to achieve the correct diagnosis. Magnetic resonance imaging with gadolinium is recommended for evaluation because these masses can be often misinterpreted as hematomas. [Orthopedics. 2016; 39(3):e545-e548.].
Matsuo, Tomoyuki; Jinji, Tsutomu; Hirayama, Daisaku; Nasu, Daiki; Ozaki, Hiroki
This study was conducted to determine whether a supination phase of the forearm exists around ball release (BRL), and, if present, to determine whether this supination is explained by a reaction force or by the body configuration required for this task. A 16-camera motion analysis system with a sampling frequency of 1,000 Hz recorded 20 healthy male semi-professional pitchers pitching from an indoor pitching mound. A short supination phase around BRL was confirmed for all participants in the current study. Correlation analyses revealed that the supination angle at BRL had significant relationships with several measurements of shoulder movement kinematics. Mechanical work analysis of the forearm's longitudinal axis revealed several variations in joint power curve and various patterns of mechanical work among the participants, suggesting that a reaction force originating from accelerating a ball might not be the main cause of supination. The raw data also were down-sampled to a sampling frequency of 250 Hz, to match previous studies and to investigate the discrepancy among previous studies concerning the existence of the supination phase. The experience of participants and methodological differences, such as the definition of BRL and the time-normalisation technique, influenced whether the supination phase was observed.
Pinerola, Jase; Ogle, Karen Craig; Wallmann, Harvey W.
ABSTRACT Background and Purpose Screening for referral, regardless of setting, is the responsibility of all physical therapists. A serious condition that sports physical therapists may encounter is upper extremity (UE) deep venous thrombosis (DVT), which can result in the important and sometimes fatal complication of pulmonary embolism. Case Description A 22 year-old male right-hand dominant collegiate pitcher was referred for physical therapist evaluation and treatment secondary to acute right UE pain and swelling. The athlete described the onset of these symptoms as insidious, denying any form of trauma. The athlete had undergone testing, which included UE Doppler ultrasound of the bilateral UE veins and a computed tomography (CT) scan of the chest without contrast; both of which were deemed negative. He was subsequently diagnosed with thoracic outlet syndrome and referred to the team physical therapist. After examination, the physical therapist hypothesized the athlete was presenting with a possible vascular compromise. Findings leading to this decision were: 1) insidious onset, 2) inability to account for the athlete's pain with ROM, strength, neurological, or provocation testing, 3) significant swelling of the right UE (arm and forearm), 4) increased discomfort with palpation in the supraclavicular region, and 5) history of strenuous UE use. Outcomes The athlete was referred back to the orthopedist. A venogram CT was ordered, which revealed an axillary and subclavian DVT and the presence of venous collaterals. The athlete was referred to a vascular surgeon who performed a right first rib removal. The athlete was able to complete post-operative rehabilitation and successfully return to competitive throwing the following spring. Discussion The delay in the initial diagnosis may have been due to the vague symptomology associated with venous complications and negative findings upon initial diagnostic testing. Conclusion This case report highlights the importance
Nakamoto, Hiroki; Mori, Shiro
The present study examined whether Go/Nogo reaction time (RT) is a relevant index of the sport expertise relating to sport-specific decision-making. 57 male university students, 20 basketball players, 24 baseball players, and 13 sedentary students as a control group, performed a Simple RT task and Go/NoGo RT task which had baseball specific stimulus-response relations. Participants in baseball and basketball differed further in having high, medium, and low experience in the sports. For comparisons across sports, the basketball and the baseball players had significantly shorter reaction times than the nonathletes in both tasks. In contrast, reaction times varied significantly across experience for the baseball players in the Go/NoGo RT task but not for basketball players. These results suggested that Go/NoGo RT could be used as an index of expertise for sport-specific decision-making, if stimulus-response relation in Go/NoGo RT task has a natural relation for a particular sport-domain.
Bishop, Stacy; Szymanski, David J; Ryan, Greg A; Herron, Robert L; Bishop, Phil A
Baseball catchers are exposed to multiple physiological challenges while playing outside during the spring and summer months, many of which deal with recovery and thermoregulation. The purpose of this study was to investigate the effect of intermittent cooling on core temperature, cardiovascular strain, exertion, and recovery during a simulated catching performance in the heat. Six trained college-aged baseball catchers performed in a controlled, hot (35 °C) and humid (25% relative humidity) environment in a counter-balanced, cross-over design. Ice vest cooling (VC) was used as a cooling modality and was compared to a control of no cooling (NC). Rectal temperature (Tre), heart rate (HR), rating of perceived exertion (RPE), and perceived recovery scale (PRS) were recorded before and after each simulated inning. All activity took place in a heat chamber, and each inning consisted of catchers receiving 12 pitches in their position followed by 6 minutes of recovery. Nine total innings were performed, and 27 total innings were performed with each of the two treatments. A significantly smaller mean Tre change was seen in VC when compared to NC (0.58 ± 0.2 °C, 0.98 ± 0.2 °C, p = < 0.01, respectively). RPE was significantly lower and PRS was significantly improved for VC compared to NC (both p ≤ 0.05). Mean recovery HR during VC was significantly lower than NC in the 5th (VC = 84 ± 8 bpm, NC = 90 ± 9 bpm, p = 0.04), 7th (VC = 84 ± 3 bpm, NC = 92 ± 7 bpm, p = 0.02), and 9th (VC = 85 ± 7 bpm, NC = 93 ± 5 bpm, p = 0.01) innings. HR during catching was significantly lower at the end of the VC trials when compared to NC (108 ± 16 bpm versus 120 ± 19 bpm, p = 0.02, respectively). VC decreased heat strain, cardiovascular strain, and RPE while it improved perceived recovery in catchers over a simulated three game series performed in hot conditions.
Hughes, Shawn S; Lyons, Brian C; Mayo, Jerry J
Bat velocity is considered to be an important factor for successful hitting. The relationship between grip strength and bat velocity has not been conclusively established. The purposes of this study were to determine the relationship of grip strength to bat velocity and to ascertain whether the performance of resistance training exercises designed to specifically target the forearms and grip would significantly alter bat velocity. The subjects for this study were 23 male members (mean +/- SD, age = 19.7 +/- 1.3 years, height = 182.5 +/- 5.9 cm, weight = 85.4 +/- 15.5 kg, experience = 14.4 +/- 1.7 years) of a varsity baseball team at a National Collegiate Athletic Association Division II school. The Jamar hand dynamometer was used to test grip strength, and the SETPRO Rookie was used to measure instantaneous bat velocity at the point of contact with the ball. Subjects were randomly divided into an experimental group and a control group. For 6 weeks, both groups participated in their usual baseball practice sessions, but the experimental group also performed extra forearm and grip strengthening exercises, whereas the control group did not. Pretest and posttest correlations between grip strength and bat velocity revealed no significant relationship between grip strength and bat velocity (pretest r = 0.054, p = 0.807; posttest r = 0.315, p = 0.145). A dependent t-test performed on all subjects revealed that a significant (p = 0.001) increase in bat velocity did occur over the course of the study. A covariate analysis, employing pretest bat velocity as the covariate, revealed no significant difference (p = 0.795) in posttest bat velocity scores between the experimental and control groups. Thus, increases in bat velocity occurred, but the differences were similar for both the experimental and control groups. The findings of this study suggest that grip strength and bat velocity are not significantly related, and that the allocation of time and energy for added training
The relative importance of resources (bottom-up forces) and natural enemies (top-down forces) for regulating food web dynamics has been debated, and both forces have been found to be critical for determining food web structure. How the relative importance of top-down and bottom-up forces varies between sites with different abiotic conditions is not well understood. Using the pitcher plant inquiline community as a model system, I examine how the relative importance of top-down and bottom-up effects differs between two disparate sites. Resources (ant carcasses) and top predators (mosquito larvae) were manipulated in two identical 4 × 4 factorial press experiments, conducted at two geographically distant sites (Michigan and Florida) within the range of the purple pitcher plant, Sarracenia purpurea, and the aquatic community that resides in its leaves. Overall, top predators reduced the density of prey populations while additional resources bolstered them, and the relative importance of top-down and bottom-up forces varied between sites and for different trophic levels. Specifically, top-down effects on protozoa were stronger in Florida than in Michigan, while the opposite pattern was found for rotifers. These findings experimentally demonstrate that the strength of predator-prey interactions, even those involving the same species, vary across space. While only two sites are compared in this study, I hypothesize that site differences in temperature, which influences metabolic rate, may be responsible for variation in consumer-resource interactions. These findings warrant further investigation into the specific factors that modify the relative importance of top-down and bottom-up effects.
Quintana, Fernando A.; Müler, Peter; Rosner, Gary L.; Munsell, Mark
We analyze complete sequences of successes (hits, walks, and sacrifices) for a group of players from the American and National Leagues, collected over 4 seasons. The goal is to describe how players’ performances vary from season to season. In particular, we wish to assess and compare the effect of available occasion-specific covariates over seasons. The data are binary sequences for each player and each season. We model dependence in the binary sequence by an autoregressive logistic model. The model includes lagged terms up to a fixed order. For each player and season we introduce a different set of autologistic regression coefficients, i.e., the regression coefficients are random effects that are specific to each season and player. We use a nonparametric approach to define a random effects distribution. The nonparametric model is defined as a mixture with a Dirichlet process prior for the mixing measure. The described model is justified by a representation theorem for order-k exchangeable sequences. Besides the repeated measurements for each season and player, multiple seasons within a given player define an additional level of repeated measurements. We introduce dependence at this level of repeated measurements by relating the season-specific random effects vectors in an autoregressive fashion. We ultimately conclude that while some covariates like the ERA of the opposing pitcher are always relevant, others like an indicator for the game being into the seventh inning may be significant only for certain seasons, and some others, like the score of the game, can safely be ignored. PMID:21909346
Fortenbaugh, Dave; Fleisig, Glenn; Onar-Thomas, Arzu; Asfour, Shihab
Coaches have identified the batter's weight shift as a critical component for promoting proper timing and balance in a baseball swing. Analysing the weight shift through maximum horizontal (Fx) and vertical (Fz) ground reaction forces (GRFs) of professional batters (N = 29; height = 185 +/- 6 cm; mass = 92 +/- 9 kg), the purpose of this study was to compare GRFs among swings against fastballs and changeups. General linear models were used to compare three conditions of interest: successful results against fastballs, successful results against changeups, and unsuccessful results against changeups. Batters had a similar loading mechanism and initial weight transfer from back foot to front foot regardless of pitch type, but peak front foot GRFx and GRFz occurred with significantly different magnitudes and at significantly different times, depending on the pitch type and hit result. Peak front foot GRFs were greater for successful swings against fastballs compared to both successful and unsuccessful swings against changeups. Peak front foot GRFs of unsuccessful swings against changeups occurred, on average, 15-20 ms earlier than successful swings against changeups and 30-35 ms earlier than successful swings against fastballs, quantifying how a changeup can disrupt the coordination of a hitter's weight shift.
Sawicki, Gregory S.; Hubbard, Mont; Stronge, William J.
Improved models for the pitch, batting, and post-impact flight phases of a baseball are used in an optimal control context to find bat swing parameters that produce maximum range. The improved batted flight model incorporates experimental lift and drag profiles (including the drag crisis). An improved model for bat-ball impact includes the dependence of the coefficient of restitution on the approach relative velocity and the dependence of the incoming pitched ball angle on speed. The undercut distance and bat swing angle are chosen to maximize the range of the batted ball. The sensitivity of the maximum range is calculated for all model parameters including bat and ball speed, bat and ball spin, and wind speed. Post-impact conditions are found to be independent of the ball-bat coefficient of friction. The lift is enhanced by backspin produced by undercutting the ball during batting. An optimally hit curve ball will travel farther than an optimally hit fastball or knuckleball due to increased lift during flight.
Sakai, Shinobu; Oda, Juhachi; Yonemura, Shigeru; Kawata, Kengo; Horikawa, Saburo; Yamamoto, Hiroyuki
The most common commercial pitching machines for baseball are the "arm" type and the "two rollers" type. These machines tend to have certain limitations. In particular, it is very difficult to simultaneously change both ball speed and direction. In addition, some types of pitches, such as the curveball or screwball, are not easily achieved. In this study, we will explain the hardware and software design of a new "intelligent" pitching machine which can pitch repeatedly with selectable speed, direction and ball rotation. The machine has three rollers and the motion of each is independently controlled by a hierarchical neural network. If the ball speed, direction and rotation are given as input data to this network, signals for controlling the three rollers are produced as output data. The results of a throw experiment with the machine that we developed are shown, which has the ability to pitch assorted breaking balls with a wide range of speeds, from 19.4 to 44.4 m/s. The machine has a speed error of less than about 3%, and a distance error of about 0.15m (twice the length of a ball's diameter).
Dowling, Brittany; Fleisig, Glenn S
Determining and understanding baseball batting mechanics at various competition levels may help players and coaches identify key kinematics crucial to being a successful hitter. The purpose of this study was to compare batting kinematics across competition levels. Kinematic and temporal data were analysed for 170 male batters (youth n = 33; high school n = 69; college n = 22; professional n = 46) using 3D motion capture (480 Hz). The results showed differences in angular positions between competition levels during the five phases of the swing, with the greatest differences seen between the youth and professional batters. At the instant of ball contact, professional batters held the bat farther away from their body, with greater back shoulder abduction (35°) and less back elbow flexion (78°) compared to youth (27° and 89°, respectively). These differences were associated with greater back elbow extension velocity for professionals (1539°/s) compared to youth (1174°/s). Additionally, higher level batters had higher bat angular and linear velocities compared to the youth batters. As batters progress through their career, they should focus on their back arm by keeping their elbow up and their arm extended in front of them.
Breslin, Carolyn W; Safer, Martin A
We investigated how event valence affected accuracy and vividness of long-term memory for two comparable public events. In 2008, 1,563 fans answered questions about objective details concerning two decisive baseball championship games between the Yankees (2003 winners) and the Red Sox (2004 winners). Both between- and within-groups analyses indicated that fans remembered the game their team won significantly more accurately than the game their team lost. Fans also reported more vividness and more rehearsal for the game their team won. We conclude that individuals rehearse positive events more than comparable negative events, and that this additional rehearsal increases both vividness and accuracy of memories about positive events. Our results differ from those of prior studies involving memories for negative events that may have been unavoidably rehearsed; such rehearsal may have kept those memories from fading. Long-term memory for an event is determined not only by the valence of the event, but also by experiences after the event.
Uchida, Yusuke; Kudoh, Daisuke; Murakami, Akira; Honda, Masaaki; Kitazawa, Shigeru
Dynamic visual acuity (DVA) is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DVA in baseball players and non-athletes using moving Landolt rings in two conditions. In the first experiment, the participants were allowed to move their eyes (free-eye-movement conditions), whereas in the second they were required to fixate on a fixation target (fixation conditions). The athletes displayed significantly better DVA than the non-athletes in the free-eye-movement conditions. However, there was no significant difference between the groups in the fixation conditions. These results suggest that the better DVA of athletes is primarily due to an improved ability to track moving targets with their eyes, rather than to improved perception of moving images on the retina.
Conroy, David E; Wolin, Kathleen Y; Carnethon, Mercedes R
Professional athletes provide high-profile role models of health and human performance. Increased body mass can be adaptive for human performance but also presents a health threat. This paper examines 145 years of data on body mass in 17,918 male professional baseball players in the United States at the time of their professional debut. Both height and weight at debut have increased over time. Controlling for age at debut, players debuting in the current decade were significantly more likely to be overweight or obese than at any time in history. The prevalence of overweight and obesity increased to approximately 70% and 10%, respectively, while normal weight prevalence decreased from approximately 60% to 20% during that time. The causes of these changes over the past 25 years are not clear although they coincide with the steroid era. These trends warrant further attention because of the potential for adverse long-term health consequences in this population and those who perceive them as role models for health and human performance.
Park, Samuel S; Loebenberg, Mark L; Rokito, Andrew S; Zuckerman, Joseph D
The extreme range of motion at the shoulder, the high angular velocities and torques, and the repetitious nature of the pitching motion combine to make the shoulder vulnerable to injury during the baseball pitch. An understanding of the biomechanics that contribute to shoulder injuries during each phase of the pitching motion can facilitate the athlete's diagnosis, treatment, and rehabilitation. Common injuries that occur during the late cocking and acceleration phases of the pitch include anterior instability and impingement, bicipital tendinitis, and subacromial impingement. Nonoperative treatment consisting of an initial period of rest and NSAIDS, followed by physical therapy and a gradual return to activity, is usually successful. When this approach fails, surgical intervention, either arthroscopic or open, may be necessary. Physical therapy and rehabilitation are directed toward restoring the integrity and strength of the dynamic and static stabilizers of the shoulder joint, yet preserving the range of motion necessary for performance. Through rehabilitation, the dedicated athlete can often return to the pitching mound at his previous level of performance.
Park, Samuel S; Loebenberg, Mark L; Rokito, Andrew S; Zuckerman, Joseph D
The extreme range of motion at the shoulder, the high angular velocities and torques, and the repetitious nature of the pitching motion combine to make the shoulder vulnerable to injury during the baseball pitch. An understanding of the biomechanics that contribute to shoulder injuries during each phase of the pitching motion can facilitate the athlete's diagnosis, treatment, and rehabilitation. The athlete's symptoms and signs, as well as radiographic imaging, are key elements in arriving at a diagnosis of shoulder injuries. Nonoperative treatment consisting of an initial period of rest and NSAIDS, followed by physical therapy and a gradual return to activity, is usually successful. When this approach fails, surgical intervention, either arthroscopic or open, may be necessary. Physical therapy and rehabilitation are directed toward restoring the integrity and strength of the dynamic and static stabilizers of the shoulder joint, yet preserving the range of motion necessary for performance. Through rehabilitation, the dedicated athlete can often return to the pitching mound at his previous level of performance.
Fleischman, M.; Kirsch, F.W.; Maginn, J.C.
The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Center (WMAC) at the University of Louisville performed an assessment at a plant manufacturing baseball bats and golf clubs -- approximately 1,500,000 bats/yr and 550,000 golf clubs/yr. To make the bats, wood billets are oven-dried and machined to a standard dimension. After sanding they are branded and finished. The golf clubs are made by finishing and assembling purchased heads and shafts. The team's report detailing findings and recommendations, indicated that the most waste, other than rinse water discharged to the publicly owned treatment works (POTW) and wood turnings which are sold, consists of scrap cardboard and paper from the shop and offices, and that the greatest savings, including new income, could be obtained by segregating the cardboard and paper wastes for sale to a local recycler.
Ohta, Yoichi; Nakamoto, Hiroki; Ishii, Yasumitsu; Ikudome, Sachi; Takahashi, Kyohei; Shima, Norihiro
This study aimed to clarify the activation characteristics of the vastus lateralis muscle in the front leg during timing correction for a sudden decrease in the velocity of a target during baseball swings. Eleven male collegiate baseball players performed coincident timing tasks that comprised constant velocity of 8 m/s (unchanged) and a sudden decrease in velocity from 8 to 4 m/s (decreased velocity). Electromyography (EMG) revealed that the muscle activation was typically monophasic when responding unchanged conditions. The type of muscle activation during swings in response to decreased velocity condition was both monophasic and biphasic. When biphasic activation appeared in response to decreased velocity, the impact time and the time to peak EMG amplitude were significantly prolonged and the timing error was significantly smaller than that of monophasic activation. However, the EMG onset from the target start was consistent both monophasic and biphasic activation in response to conditions of decreased velocity. In addition, batters with small timing errors in response to decreased velocity were more likely to generate biphasic EMG activation. These findings indicated that timing correction for a sudden decrease in the velocity of an oncoming target is achieved by modifying the muscle activation characteristics of the vastus lateralis muscle of front leg from monophasic to biphasic to delay reaching peak muscle activation and thus prolong impact time. Therefore, the present findings suggests that the extent of timing errors in response to decreased velocity is influenced by the ability to correct muscle activation after its initiation rather than by delaying the initiation timing of muscle activation during baseball swings. PMID:25918848
Lehman, Graeme; Drinkwater, Eric J; Behm, David G
Baseball-specific athleticism, potential, and performance have been difficult to predict. Increased muscle strength and power can increase throwing velocity but the majority of research has focused on the upper body. The present study sought to determine if bilateral or unilateral lower-body field testing correlates with throwing velocity. Baseball throwing velocity scores were correlated to the following tests: medicine ball (MB) scoop toss and squat throw, bilateral and unilateral vertical jumps, single and triple broad jumps, hop and stop in both directions, lateral to medial jumps, 10- and 60-yd sprints, and both left and right single-leg 10-yd hop for speed in 42 college baseball players. A multiple regression analysis (forward method), assessing the relationship between shuffle and stretch throwing velocities and lower-body field test results determined that right-handed throwing velocity from the stretch position was most strongly predicted by lateral to medial jump right (LMJR) and body weight (BW; R = 0.322), whereas lateral to medial jump left (LMJL; R = 0.688) predicted left stretch throw. Right-handed shuffle throw was most strongly predicted by LMJR and MB scoop (R = 0.338), whereas LMJL, BW, and LMJR all contributed to left-handed shuffle throw (R = 0.982). Overall, this study found that lateral to medial jumps were consistently correlated with high throwing velocity in each of the throwing techniques, in both left-handed and right-handed throwers. This is the first study to correlate throwing velocity with a unilateral jump in the frontal plane, mimicking the action of the throwing stride.
Dodd, Daniel J; Alvar, Brent A
Complex training is the simultaneous combination of heavy resistance training and plyometrics. The objective of this study was to test the effects of complex training vs. heavy resistance or plyometric interventions alone on various power-specific performance measures. Forty-five male division II junior college baseball players participated in 3 separate 4-week resistance training interventions. Subjects were randomly assigned to one of three groups. In a counterbalanced rotation design, each group participated in complex, heavy resistance, and plyometric training interventions. Each individual was tested in 20-yd (SP20), 40-yd (SP40), 60-yd (SP60), vertical jump, standing broad jump, and T-agility measures pre- and post-4-week training interventions. There was no statistical significant difference (p = 0.11) between groups across all performance measures. Review of each distinct training intervention revealed greater percent improvements in SP20 (0.55; -0.49; -0.12), SP40 (0.26; -0.72; -1.33), SP60 (0.27; 0.15; -0.27), standing broad jump (1.80; 0.67; 1.1), and T-agility (2.33; 1.23; -0.04) with complex training interventions than with the heavy resistance or plyometric training interventions, respectively. Plyometric-only training showed greater percent changes in vertical jump (1.90) than with complex (0.97) or heavy resistance training (0.36). The present results indicate that complex training can provide strength and conditioning professionals equal, if not slightly greater, improvements in muscular power than traditional heavy resistance- and plyometric-only interventions in moderately trained athletes. Complex training can be another valuable method for short-term power and speed improvements in athletes in isolation or in conjunction with other power development methods.
Conte, Stan; Camp, Christopher L; Dines, Joshua S
Since Major League Baseball (MLB) expanded to its current size of 30 teams in 1998, a comprehensive and longitudinal study of injury trends has not been performed. The purpose of this work is to report the epidemiology of injuries in MLB over that time utilizing disabled list (DL) data. Additionally, we sought to determine the financial impact of these injuries for MLB teams. During this analysis, we focused special attention on injuries of the medial ulnar collateral ligament (MUCL) and conducted a comprehensive review of all MUCL reconstructions ever performed on MLB players. Over the study period, there were a total of 8357 DL designations (mean of 464 annually). Players lost a total of 460,432 days (25,186 days annually) due to injury. Both the number of DL assignments and number of DL days increased from year to year (P < .001 and P = .003, respectively). Average length of DL assignments remained steady over time at 55.1 days (P = .647). Although shoulder injuries decreased (P = .023), this was met with a reciprocal increase in elbow injuries (P = .015). The average annual cost of designating players to the DL was $423,267,634 and a total of $7,618,817,407 was spent over the entire 18 seasons. Regarding MUCL injuries, a total of 400 MUCL reconstructions were performed in MLB players between 1974 and 2015, and the mean time to return to MLB competition was 17.1 months. The annual incidence of MUCL reconstructions increased dramatically from year to year (P < .001) and nearly one-third (n = 131, 32.8%) of all procedures performed over the 42-year period occurred in the last 5 years (2011 to 2015). In summary, overall injury rates and DL assignments continue to rise. Although shoulder injuries are declining, this improvement is countered by increasing elbow injuries, and these injuries continue to represent a significant source of lost revenue.
Sherlin, Leslie H; Larson, Noel C; Sherlin, Rebecca M
Neurofeedback may be useful for improving sports performance but few studies have examined this potential. Here we present data of five development players from a major league baseball team. The aims were to evaluate the feasibility of conducting sessions within a professional organization, assess changes in quantitative electroencephalograph (QEEG), NeuroPerformance Profile™, and report qualitative self-report data before and after brain training. The EEG was recorded with 19 electrodes for 20 min of baseline conditions and approximately 21 min of a continuous performance test. The fast Fourier transform analysis provided average cross-spectral matrices for bands delta (1-3.5 Hz), theta (4-7.5 Hz), alpha (8-12 Hz), low beta (13-16 Hz), beta 1 (13-21 Hz), beta 2 (22-32 Hz), and gamma (32-45 Hz) from the pre and post intervention evaluations in the baseline condition of eyes open. The continuous performance test metrics included the errors of omission, errors of commission, response time and response time variability. The 9 scales of the NeuroPerformance Profile™ were examined. The QEEG data, CPT data and NeuroPerformance Profile™ data were all compared between the pre and post 15 sessions of brain training using a within subject paired t test design corrected for multiple comparisons using false discovery rate method. Following brain training, comparative QEEG, CPT and NeuroPerformance Profile™ analyses illustrated significant differences. The QEEG findings of all participants illustrated significant changes within the training parameters but also across other frequency bands and electrode sites. Overall, the positive findings in both objective and subjective measures suggest further inquiry into the utility of brain training for performance enhancement with the specific application of sport is warranted. Particularly QEEG and CPT gains were noted in the areas that correspond to client self-report data demonstrating improvement in attention, decreased
Lin, Hwai-Ting; Ko, Hsing-Tsen; Lee, Kung-Che; Chen, Ying-Cheng; Wang, Dean-Chuan
[Purpose] This study aimed to investigate the effect of shoulder positions and speeds on internal and external rotation torque of college baseball players and age-matched non-players. [Subjects] Twenty first-level collegiate baseball players and 19 college students were recruited. [Methods] A dynamometer system was used to evaluate the shoulder rotation strength in sitting postures. Three testing positions, namely shoulder abduction of 45°, 70°, and 90° in the scapular plane, were combined with three testing speeds at 60°/s, 120°/s, and 210°/s. [Results] The maximum external and internal rotation torques both occurred at shoulder abduction of 70°. However, only external rotation torque was affected by the speed, with the peak value observed at 60°/s. The internal rotation torque of baseball players was larger than that of the control group under all testing conditions, but the external rotation did not show any difference. The ratio of external to internal rotation torque changed with the testing positions and speeds in both groups. The ratio in the control group was greater than that in the player group. [Conclusion] The shoulder position could affect the rotational strength, and the baseball players could strengthen their external rotators for better performance and injury prevention. PMID:26157263
Cross, Tracy L.
In this column, the author uses the analogy of baseball to describe the lives of gifted children as a vehicle to think about similarities and differences. The author states that he has experienced how educators often gloss over the powerful and all-inclusive living conditions of high-ability students from financially impoverished backgrounds. In…
Song, Hong-Sun; Woo, Seung-Seok; So, Wi-Young; Kim, Kwang-Jun; Lee, Joohyung; Kim, Joo-Young
Functional Movement Screen (FMS) is a way to pretest functional movement. This study examined the effects of the FMS training program on the strength and flexibility of 62 elite male high school baseball players (31 in the training group, 31 in the control group). All players who received less than two points on each FMS test item had to join the 16-week, three times weekly FMS training program. To analyze results among the FMS participants, measures including intraclass correlation coefficient (ICC) and repeated measure ANOVA were utilized. The Kappa coefficient was 0.805 when the intraclass correlation coefficient of the three participants was inspected. Strength showed a significant interaction depending on time and group (hand grip strength: P=0.011, bench press and squat both for one-repetition maximum (1RM): P=0.001 and P=0.008, respectively). Back muscle strength did not show a significant difference (P=0.660). Trunk forward flexion showed no interaction depending on time and groups (P=0.983) but trunk extension backward showed significant differences depending on groups (P=0.004) and time (P=0.001). Splits showed a significant difference depending on time and groups (P=0.004). The FMS training program improved the strength and flexibility of elite high school baseball players.
Sulloway, Frank J; Zweigenhaft, Richard L
According to expectations derived from evolutionary theory, younger siblings are more likely than older siblings to participate in high-risk activities. The authors test this hypothesis by conducting a meta-analysis of 24 previous studies involving birth order and participation in dangerous sports. The odds of laterborns engaging in such activities were 1.48 times greater than for firstborns (N = 8,340). The authors also analyze performance data on 700 brothers who played major league baseball. Consistent with their greater expected propensity for risk taking, younger brothers were 10.6 times more likely to attempt the high-risk activity of base stealing and 3.2 times more likely to steal bases successfully (odds ratios). In addition, younger brothers were significantly superior to older brothers in overall batting success, including two measures associated with risk taking. As expected, significant heterogeneity among various performance measures for major league baseball players indicated that older and younger brothers excelled in different aspects of the game.
Fairbrother, Jeffrey T.; Post, Phillip G.; Whalen, Sam J.
The advantages on an external focus of attention have been demonstrated for a variety of sport tasks. The constrained action hypothesis (Wulf et al., 2001) argues that focusing externally on the movement effect results in the use of automated processes for movement control. In contrast, focusing internally in an attempt to control the movements of the body disrupts normally automated processes and degrades performance. Research on experts, however, suggests that they may adopt more complex attentional strategies. The present study provided a unique opportunity to examine expert horseshoe players’ attentional strategies as indicated by their self-reported responses to questions included in a National Horseshoe Pitchers Association (NHPA) player profile questionnaire. Responses submitted by 83 top NHPA players were examined to determine the frequency of references to the use of internal and external focus points and identify categories related to attentional strategies. Results indicated that the large majority of players reported using focus points that are consistent with an external focus of attention and that their thoughts corresponded to one or more categories related to technique, mental focus or concentration, general success, use of external focus cues, and emotional control. The findings are consistent with the view that experts may adopt complex attentional strategies that encompass both an external focus and thoughts about a variety of other performance related factors. PMID:27458419
Fairbrother, Jeffrey T; Post, Phillip G; Whalen, Sam J
The advantages on an external focus of attention have been demonstrated for a variety of sport tasks. The constrained action hypothesis (Wulf et al., 2001) argues that focusing externally on the movement effect results in the use of automated processes for movement control. In contrast, focusing internally in an attempt to control the movements of the body disrupts normally automated processes and degrades performance. Research on experts, however, suggests that they may adopt more complex attentional strategies. The present study provided a unique opportunity to examine expert horseshoe players' attentional strategies as indicated by their self-reported responses to questions included in a National Horseshoe Pitchers Association (NHPA) player profile questionnaire. Responses submitted by 83 top NHPA players were examined to determine the frequency of references to the use of internal and external focus points and identify categories related to attentional strategies. Results indicated that the large majority of players reported using focus points that are consistent with an external focus of attention and that their thoughts corresponded to one or more categories related to technique, mental focus or concentration, general success, use of external focus cues, and emotional control. The findings are consistent with the view that experts may adopt complex attentional strategies that encompass both an external focus and thoughts about a variety of other performance related factors.
Leftwich, Heidi K; Alves, Marcus Vinicius Ortega
Adolescent pregnancy, although on the decline, represents a significant public health concern. Often adolescents present late to prenatal care, either from lack of knowledge, fear of consequences, limited access, stigma, or all of the above. Although multifaceted, there are many risks both to mother and child that are increased in adolescent pregnancy. Many are unintended and are at risk for repeat adolescent pregnancy, especially within the first 2 years. Risks include but are not limited to: low birth weight, preterm delivery, stillbirth, and preeclampsia, as well as feelings of social isolation, delayed or neglected educational goals, and maternal depression.
Gilbert, Andrée; Maheux, Brigitte; Frappier, Jean-Yves; Haley, Nancy
OBJECTIVE To investigate how often family physicians see adolescents with mental health problems and how they manage these problems. DESIGN Mailed survey completed anonymously. SETTING Province of Quebec. PARTICIPANTS All 358 French-speaking family physicians who practise primarily in local community health centres (CLSCs), including physicians working in CLSC youth clinics, and 749 French-speaking practitioners randomly selected from private practice. MAIN OUTCOME MEASURES Frequency with which physicians saw adolescents with mental health problems, such as depression, suicidal thoughts, behavioural disorders, substance abuse, attempted suicide, or suicide, during the last year or since they started practice. RESULTS Response rate was 70%. Most physicians reported having seen adolescents with mental health problems during the last year. About 10% of practitioners not working in youth clinics reported seeing adolescents with these disorders at least weekly. Anxiety was the most frequently seen problem. A greater proportion of physicians working in youth clinics reported often seeing adolescents for all the mental health problems examined in this study. Between 8% and 33% of general practitioners not working in youth clinics said they had not seen any adolescents with depression, behavioural disorders, or substance abuse. More than 80% of physicians had seen adolescents who had attempted suicide, and close to 30% had had adolescent patients who committed suicide. CONCLUSION Family physicians play a role in adolescent mental health care. The prevalence of mental health problems seems higher among adolescents who attend youth clinics. Given the high prevalence of these problems during adolescence, we suggest on the basis of our results that screening for these disorders in primary care could be improved. PMID:17279202
Roedl, Johannes B; Gonzalez, Felix M; Zoga, Adam C; Morrison, William B; Nevalainen, Mika T; Ciccotti, Michael G; Nazarian, Levon N
Purpose To evaluate a combined imaging approach with both ultrasonography (US; conventional US and valgus stress US) and magnetic resonance (MR) arthrography in baseball players with medial elbow pain. Materials and Methods Institutional review board approval was obtained and the requirement for informed consent was waived. The study is compliant with HIPAA. Baseball players with medial elbow pain underwent US in addition to MR arthrography. Findings were assessed with each modality alone and both combined in this retrospective investigation. For the evaluation of ulnar collateral ligament (UCL) tears with stress US, the interval gapping of the medial elbow joint was measured between rest and valgus stress both at the injured and at the uninjured (contralateral) elbow. Surgical or arthroscopic correlation was available as the so-called gold standard. McNemar tests compared the accuracies of the imaging modalities. Results In this study, 144 baseball players had 191 findings of medial elbow pain, including 53 UCL tears. With stress US, joint gapping at the injured elbow greater than 1.0 mm compared with the contralateral elbow yielded a sensitivity, specificity, and accuracy of 96%, 81%, and 87%, respectively, for diagnosing UCL tears. With MR arthrography, the sensitivity, specificity, and accuracy for UCL tears were 81%, 91%, and 88%, respectively, and increased to 96% (P = .013, McNemar test), 99% (P = .023), and 98% (P < .001), respectively, when combined with US to a dual modality MR and US approach. For 31 patients with ulnar neuritis, the sensitivity, specificity, and accuracy increased from 74%, 92%, and 88%, respectively, with MR arthrography alone to 90% (P = .07, McNemar test), 100% (P < .001), and 98% (P < .001) combined with US. For the 59 myotendinous and the 48 osteochondral diagnoses, the sensitivity, specificity, and accuracy with MR arthrography alone were 93%, 93%, and 93%, and 94%, 98%, and 97%, respectively, with no additional diagnostic value
Ippolito, Jacy, Ed.; Steele, Jennifer L., Ed.; Samson, Jennifer F., Ed.
"Adolescent Literacy" initially appeared as a special issue of the "Harvard Educational Review". It explores key issues and debates in the adolescent literacy crisis, the popular use of cognitive strategies, and disciplinary and content-area literacy. Also examined are alternative forms of literacy, afterschool interventions, new instruction…
Foreman, Susan; Seligman, Linda
Discusses legal and developmental aspects of adolescent abuse, as distinguished from child abuse. The role of the school counselor in identifying and counseling abused adolescents and their families is discussed and several forms of intervention and support services are described. (JAC)
Research has suggested that the incidence of loneliness peaks at adolescence and decreases with age. Changes in the determinants of loneliness during adolescence were investigated for grade 8, grade 11, and university students. Subjects (N=410) completed a written questionnaire which included ten items from the UCLA Loneliness Scale, the…
Examines recent empirical evidence to test theories postulated in separate works by G. Stanley Hall and Anna Freud that adolescents must experience psychological turbulence in the transition to adulthood. Concludes that turmoil is no longer a necessary condition of adolescence and that those who do experience it need psychiatric attention.…
Onga, Takafumi; Yamamoto, Tetsuji; Akisue, Toshihiro; Marui, Takashi; Kurosaka, Masahiro
Tendinitis of the long head of the biceps brachii muscle is commonly seen in athletes who do repetitive overhead motions. Common causes of biceps tendinitis include impingement syndrome, subluxation of the biceps tendon, and attrition tendinitis, whereas biceps tendinitis secondary to a bone neoplasm is rare. A case of biceps tendinitis caused by an osteochondroma arising in the left humeral bicipital groove in a 25-year-old male baseball player is reported. The tumor was hook-shaped, originated from the inferomedial portion of the humeral lesser tubercle, and surrounded the biceps tendon. Symptoms of increasing pain and inability to throw resulted from direct irritation of the biceps tendon by the tumor. Total excision of the tumor relieved the symptoms within 3 weeks. To our knowledge, there have been no reported cases in the English-language literature of biceps tendinitis caused by an osteochondroma.
Sherwin, Jason; Muraskin, Jordan; Sajda, Paul
Hitting a baseball is often described as the most difficult thing to do in sports. A key aptitude of a good hitter is the ability to determine which pitch is coming. This rapid decision requires the batter to make a judgment in a fraction of a second based largely on the trajectory and spin of the ball. When does this decision occur relative to the ball's trajectory and is it possible to identify neural correlates that represent how the decision evolves over a split second? Using single-trial analysis of electroencephalography (EEG) we address this question within the context of subjects discriminating three types of pitches (fastball, curveball, slider) based on pitch trajectories. We find clear neural signatures of pitch classification and, using signal detection theory, we identify the times of discrimination on a trial-to-trial basis. Based on these neural signatures we estimate neural discrimination distributions as a function of the distance the ball is from the plate. We find all three pitches yield unique distributions, namely the timing of the discriminating neural signatures relative to the position of the ball in its trajectory. For instance, fastballs are discriminated at the earliest points in their trajectory, relative to the two other pitches, which is consistent with the need for some constant time to generate and execute the motor plan for the swing (or inhibition of the swing). We also find incorrect discrimination of a pitch (errors) yields neural sources in Brodmann Area 10, which has been implicated in prospective memory, recall, and task difficulty. In summary, we show that single-trial analysis of EEG yields informative distributions of the relative point in a baseball's trajectory when the batter makes a decision on which pitch is coming.
... Español Text Size Email Print Share Stages of Adolescence Page Content Article Body Adolescence, these years from puberty to adulthood, may be roughly divided into three stages: early adolescence, generally ages eleven to fourteen; middle adolescence, ages ...
Chin, Lijin; Chung, Arthur Y C; Clarke, Charles
Pitcher plants of the genus Nepenthes capture a wide range of arthropod prey for nutritional benefit, using complex combinations of visual and olfactory signals and gravity-driven pitfall trapping mechanisms. In many localities throughout Southeast Asia, several Nepenthes different species occur in mixed populations. Often, the species present at any given location have strongly divergent trap structures and preliminary surveys indicate that different species trap different combinations of arthropod prey, even when growing at the same locality. On this basis, it has been proposed that co-existing Nepenthes species may be engaged in niche segregation with regards to arthropod prey, avoiding direct competition with congeners by deploying traps that have modifications that enable them to target specific prey types. We examined prey capture among 3 multi-species Nepenthes populations in Borneo, finding that co-existing Nepenthes species do capture different combinations of prey, but that significant interspecific variations in arthropod prey combinations can often be detected only at sub-ordinal taxonomic ranks. In all lowland Nepenthes species examined, the dominant prey taxon is Formicidae, but montane Nepenthes trap few (or no) ants and 2 of the 3 species studied have evolved to target alternative sources of nutrition, such as tree shrew feces. Using similarity and null model analyses, we detected evidence for niche segregation with regards to formicid prey among 5 lowland, sympatric Nepenthes species in Sarawak. However, we were unable to determine whether these results provide support for the niche segregation hypothesis, or whether they simply reflect unquantified variation in heterogeneous habitats and/or ant communities in the study sites. These findings are used to propose improvements to the design of field experiments that seek to test hypotheses about targeted prey capture patterns in Nepenthes.
Cook, Mary N.; Peterson, John; Sheldon, Christopher
Depression in adolescence and adulthood is common, afflicting up to 20 percent of these populations. It represents a significant public health concern and is associated with considerable suffering and functional impairment. Adolescent-onset depression tends to be a particularly malignant and recalcitrant condition, increasing the likelihood of recurrence and chronicity in adulthood. Clinical presentations for various medical and psychiatric conditions, as well as reactions to psychosocial stressors, can mimic or confound the picture of depression in adolescents. Therefore, careful assessment and differential diagnosis is essential. Effective treatments, both pharmacological and psychosocial in nature, exist, and so early detection and intervention is paramount. This article presents an overview of optimal prevention, assessment, and clinical decision-making strategies for managing depression in adolescents. PMID:19855857
Lee, Jinyoung; Song, Hongsun; Kim, Sunghwan; Woo, Seungseok
Objective To investigate the effects of glenohumeral internal rotation deficit (GIRD) on the isokinetic strength, body pain, and the quality of life in male high school baseball players of Korea. Methods Fifty-six male high school baseball players were divided into either group A (GIRD≥20°, n=12) or group B (GIRD<20°, n=44). The range of motion in the shoulder and the isokinetic strength were measured. Questionnaires were administered regarding the body pain location by using the visual analogue scale, and the quality of life was measured by using the SF-36 Form. Results All subjects had increased external rotation range of motion and decreased internal rotation in the throwing shoulder. The incidence of GIRD (≥20°) was 21.43% in the present study. In the isokinetic strength test, a significantly weaker muscular state at an angular velocity of 180°/s was observed in group A, compared to group B. For the comparison of the pain, the frequency of shoulder pain was higher (33.93%) than other body pain, among the study subjects. Conclusion GIRD is one of the main risk factors of glenohumeral joint damage, and it is correlated with reduced isokinetic strength and quality of life. High school baseball players will need appropriate shoulder rehabilitation programs for the improvement in their quality of life and performance. PMID:25932414
Hochi, Yasuyuki; Mizuno, Motoki; Nakayama, Takahiro; Kitamura, Kaoru
The purpose of this study was to examine the effect in the experience of TB among university baseball team from the view point of team-vitalization. We carry out one university baseball team (102 males, 6 female). The average age of the participants was 19.99 years (SD = 1.41). Then, using Check List of Team- Vitalization that was developed by consulting firm in Japan, we examined the degrees of team-vitalization. The answers of this investigation were collected from the participants at fifth times (before intervention of TB, immediately after TB, after three months of TB, before intervention of follow-up training of TB, and immediately after follow-up training of TB). This study for eight months provided the following three conclusions; 1) University baseball team was vitalized through the experience of TB. 2) Team-vitalization was higher than before TB experience, but this effect of the TB did not seem to be permanent. 3) To keep intervention of TB was very important.
Similar photoperiod-related birth seasonalities among professional baseball players and lesbian women with an opposite seasonality among gay men: Maternal melatonin may affect fetal sexual dimorphism.
Based on pre-mid-20th-century data, the same photoperiod-related birth seasonality previously observed in schizophrenia was also recently found in neural-tube defects and in extreme left-handedness among professional baseball players. This led to a hypothesis implicating maternal melatonin and other mediators of sunlight actions capable of affecting 4th-embryonic-week developments including neural-tube closure and left-right differentiation of the brain. Here, new studies of baseball players suggest that the same sunlight actions could also affect testosterone-dependent male-female differentiation in the 4-month-old fetus. Independently of hand-preferences, baseball players (n=6829), and particularly the stronger hitters among them, showed a unique birth seasonality with an excess around early-November and an equally significant deficit 6 months later around early-May. In two smaller studies, north-American and other northern-hemisphere born lesbians showed the same strong-hitter birth seasonality while gay men showed the opposite seasonality. The sexual dimorphism-critical 4th-fetal-month testosterone surge coincides with the summer-solstice in early-November births and the winter-solstice in early-May births. These coincidences are discussed and a "melatonin mechanism" is proposed based on evidence that in seasonal breeders maternal melatonin imparts "photoperiodic history" to the newborn by direct inhibition of fetal testicular testosterone synthesis. The present effects could represent a vestige of this same phenomenon in man.
Grant, L M; Demetriou, E
The consequences of adolescent sexual behavior are an enormous burden both for the adolescent and society. The problem is not that teens are sexually active but rather that they have little preparation and guidance in developing responsible sexual behavior. Developmentally, adolescents reach physical maturity before they are cognitively able to appreciate the consequences of their behavior. A teenager's primary source of information regarding sexuality is his or her peer group, all of whom are experiencing and reinforcing the same behaviors. The family, the major socializer of other behaviors, is not as powerful a force in shaping responsible sexual behavior because of parental discomfort with sex education and sexual discussions. This is the result of a social milieu in which sex is frequently portrayed but rarely linked with responsible behavior or accurate, nonjudgmental information. The pediatric practitioner is in an ideal position to intervene in these dynamics. In the office, the practitioner can provide accurate sexual information to both parents and adolescents, support parental-child communication on sexual issues, and provide appropriate services or referral. In the community, the practitioner can advocate for school-based sex education as well as act as an information resource. Finally, the practitioner can advocate for the health care needs for adolescents on a national level, supporting legislation that provides adolescents with information and access to services necessary to make responsible sexual decisions.
Veliz, Philip Todd; Boyd, Carol J.; McCabe, Sean Esteban
Background The empirical research examining the impact of sports participation on alcohol and other drug use has produced mixed results. Part of this problem may be the result of how different types of sports participation create different experiences that shape certain types of behaviors that either facilitate or deter substance use. Objectives We examined the association between different types of competitive sports participation and substance use among a nationally representative sample of adolescents. Methods Two recent cross-sections from the Monitoring the Future were merged to capture a large subsection of adolescents who participate in either high-contact sports (football, wrestling, hockey and lacrosse), semi-contact sports (baseball, basketball, field hockey and soccer), and non-contact sports (cross-country, gymnastics, swimming, tennis, track, and volleyball). Results Multivariate analyses revealed that adolescents who participated in high-contact sports had higher odds of using substances during the past 30 days and initiating substance use at early ages. Further, adolescents who participated in non-contact sports had lower odds to indicate smoking cigarettes and marijuana during the past 30 days. Conclusions Parents, educators, and policy makers need to consider that some sporting contexts may be a catalyst to engage in risky behaviors like substance use. PMID:25290659
Eugene Coleman, A; Amonette, William E
The purposes of this research were to (a) quantify interval sprint times between Home-Plate and the Foul-Line and the Foul-Line and First-Base, (b) determine if differences exist in interval velocities and acceleration between left- and right-handed batters or between-position groupings, and (c) to quantify determinants of time to First-Base in Major-League Baseball players during actual games. A total of 1,896 sprint times to the Foul-Line (13.7 m) and First-Base (27.4 m) were recorded in 302 baseball players by a single coach, positioned in the dugout with a hand-held stopwatch. Interval velocities and accelerations were computed between Home-Plate and the Foul-Line and the Foul-Line and First-Base; average velocity and acceleration were also determined over the entire 27.4 m. Velocity and acceleration for left-handed batters were greater than for right-handed batters from Home-Plate to the Foul-Line and from Home-Plate to First-Base; however, there were no differences in velocity or acceleration from the Foul-Line to First-Base. Interval velocity was significantly greater for outfielders and infielders compared with that for catchers from Home-Plate to the Foul-Line and from the Home-Plate to First-Base. Outfielders were faster than catchers from the Foul-Line to First-Base; no other between-group differences were evident. Accelerations from Home-Plate to the Foul-Line and from Home-Plate to First-Base were greater for outfielders compared with infielders and catchers. Infielders accelerated at greater rates than did catchers between these intervals. There were no between-position differences in acceleration from the Foul-Line to First-Base. These data indicate that time to First-Base is most affected by acceleration from Home-Plate to the Foul-Line. Coaches should implement strategies that encourage players to sprint maximally over the first 13.7 m to maximize chances of successfully reaching First-Base.
Ng, Wuey Min; Chan, Chee Ken; Takahashi, Norimasa; Kawai, Nobuaki; Teh, Kok Kheng; Saravana, R; Sugaya, Hiroyuki
INTRODUCTION Injuries to the medial structures of the elbow due to overhead throwing games are well documented. However, variations of medial epicondyles are not well described, especially in athletes with fused medial epicondyles. In this study, we evaluated variations in the medial epicondyle of baseball players who were aged 15–17 years and had fused epicondyles. METHODS In this cross-sectional observational study, 155 skeletally mature baseball players with unilateral medial elbow pain and 310 elbow radiographs were reviewed by two independent reviewers. The medial epicondyles were categorised into three groups: normal, elongated or separated. RESULTS Among the 155 patients, 65 (41.9%) had normal epicondyles, 41 (26.5%) had elongated epicondyles and 49 (31.6%) had separated epicondyles. The medial epicondyle was larger on the dominant arm for 125 (80.6%) patients; the mean surface area on the dominant arm was 222.50 ± 45.77 mm2, while that of the non-dominant arm was 189.14 ± 39.56 mm2 (p < 0.01). Among the three categories of medial epicondyles, separated epicondyles had the largest surface area, followed by elongated and normal epicondyles. CONCLUSION Medial epicondyles in adolescent throwing athletes can be categorised into three different groups according to their shape (normal, elongated and separated). We observed a correlation between the shape and the surface area of the medial epicondyle in adolescent throwing athletes, with separated medial epicondyles having the largest surface area. Further studies and follow-up are needed to determine the prognostic value and clinical significance of these morphological variations. PMID:26976222
Huang, Yung-Hsien; Wu, Ting-Yu; Learman, Kenneth E; Tsai, Yung-Shen
Risk factors in throwing factors associated to little league elbow have not been adequately explored. Whether these factors also affect the players' performance is also important to elucidate while modifying throwing pattern to reduce injury. The purpose of this study was to compare the differences in throwing kinematics between youth baseball players with or without a history of medial elbow pain (MEP) and to determine the relationship between their throwing kinematics and ball speed. Fifteen players with previous MEP were matched with 15 healthy players by age, height and weight. Throwing kinematics was recorded by an electromagnetic motion analysis system. A foot switch was used for determining foot off and foot contact. Ball speed was recorded with a sports radar gun. The group with a history of MEP demonstrated less elbow flexion angle at maximum shoulder external rotation and had more lateral trunk tilt at ball release compared to the healthy group. The group with a history of MEP also had faster maximum upper torso rotation velocities, maximum pelvis rotation velocities and ball speeds. Maximum shoulder external rotation angle (r = 0.458, P = 0.011), elbow flexion angle at maximum shoulder external rotation (r = -0.637, P = 0.0003), and maximum upper torso rotation velocity (r = 0.562, P = 0.002) had significant correlation with ball speed. Findings of this study can be treated as elbow injury-related factors that clinicians and coaches can attend to when taking care of youth
Saint Onge, Jarron M; Krueger, Patrick M; Rogers, Richard G
We employ a unique dataset of Major League Baseball (MLB) players - a select, healthy population - to examine trends in height, weight, and body mass in birth cohorts from 1869 to 1983. Over that 115-year time period, U.S. born MLB players have gained, on average, approximately 3 in. (7.6 cm) in height and 27.0 lb (12.2 kg) in weight, which has contributed a 1.6-unit increase in the body mass index. Where comparable data are available, U.S. born MLB players are about 2.0 in. (5.1cm) taller and 20.0 lb (9.1 kg) heavier but substantially less obese than males in the general U.S. population. But both groups exhibit similar height and weight trends; the majority of height and weight gains take place in cohorts that were born prior to World War II, followed by slower gains and occasional declines in height and weight for cohorts born in 1939 and later.
Mair, Scott D; Uhl, Tim L; Robbe, Rudy G; Brindle, Kathleen A
The purpose of this study was to document range-of-motion differences and radiographic changes in the dominant shoulder of skeletally immature throwers and to determine how pain associated with throwing may relate to these changes. Seventy-nine male youth baseball players (aged 8-15 years) completed a questionnaire, a shoulder examination, and a series of radiographs to determine physeal changes and humeral retroversion. Radiographs were reviewed and interpreted by a blinded musculoskeletal radiologist. Measurement of proximal humeral physeal width revealed a significant increase on the dominant side for the entire group, in subjects with a history of symptoms during the current season, and in subjects who had never had symptoms. Visual radiographic changes were commonly found in subjects with a history of pain (16/26 [62%]) as well as in those subjects without symptoms (29/53 [55%]). Subjects had increased external rotation of the dominant arm as compared with the nondominant arm, and this pattern increased in magnitude as the throwers aged. Range-of-motion and radiographic asymmetry of the shoulders is common, is often asymptomatic, and may represent adaptive changes in this population.
... Children and Adolescents Go Back Treating Children and Adolescents Email Print + Share For the most part, the ... tailored, based upon the child's weight. Children and adolescents are moving through a period of physical and ...
Williams-Evans, Shiphrah A; Myers, Joy Sher'ron
The purpose of this document is to provide an overview of the rising occurrences of adolescent violence in the American school systems and how various theories can be used to assist in understanding this phenomenon. The authors have become increasingly interested in this topic, after direct involvement in the summer of 2001. There were a number of students who were attending summer school as a result of consistent out-of-school suspensions for violent acts. The procedure to process through the system with these students was to suspend them, resulting in the student subsequently failing their present grade. The school was located in a community known for its high rate of violence and criminal activity. Various types of adolescent violence exist in our schools. Studies have reported that violent adolescents may come from familial environments that are full of social and interpersonal conflicts (Gray & Foshee, 1999). This paper discusses the development of a research plan to investigate the number and type of adolescent violent occurrences in a southern middle school setting.
Stronski Huwiler, S M; Remafedi, G
Homosexuality has existed in all civilizations, but societal disapproval and cultural taboos have negatively influenced its recognition. A significant percentage of youths identify themselves as homosexual, and even more experience sex with the same sex or are confused about sexual feelings. A unifying etiological theory attributes the expression of sexual orientation to genes that shape the central nervous system's development, organization, and structure via prenatal sex steroids. Environmental factors may influence the expression of genetic potential. Several models of psychosocial development describe initial stages of awareness and confusion about same-sex attractions, followed by acknowledgement of homosexuality, disclosure to others, and eventual integration of sexual identity into a comprehensive sense of self. Stressors related to isolation, stigma, and violence may predispose homosexual adolescents to impaired social, emotional, and physical health, resulting in depression and suicide, school problems, substance abuse, running away eating disorders, risky sexual behavior, and illegal conduct. As with all adolescents, the overall goals in the care of homosexual youth are to promote normal adolescent development, social and emotional well-being, and physical health. A comprehensive, multidisciplinary approach is required to address medical, mental health, and psychosocial issues within the context of the adolescents' community and culture.
The Effects of a Sports Nutrition Education Intervention on Nutritional Status, Sport Nutrition Knowledge, Body Composition, and Performance during Off Season Training in NCAA Division I Baseball Players.
Rossi, Fabrício Eduardo; Landreth, Andrew; Beam, Stacey; Jones, Taylor; Norton, Layne; Cholewa, Jason Michael
This study investigated the effects of a sport nutrition education intervention (SNEI) on dietary intake, knowledge, body composition, and performance in NCAA Division I baseball players. Resistance trained NCAA Division I baseball players (82.4 ± 8.2 kg; 1.83 ± 0.06 m; 13.7 ± 5 % body fat) participated in the study during 12 weeks of off-season training. Fifteen players volunteered for SNEI while 15 players matched for position served as controls (C) for body composition and performance. The nutrition intervention group (NI) received a 90 min SNEI encompassing energy intake (Kcal), carbohydrate (CHO), protein (PRO), fat, food sources, and hydration. Sport nutrition knowledge questionnaires were administered to NI pre and post. Nutritional status was determined by three-day dietary logs administered to NI pre and post. Body composition and performance (5-10-5 shuttle test, vertical jump, broad jump, 1 RM squat) were measured pre and post for C and NI. Knowledge increased in NI. Pro and fat, but not CHO intake increased in NI. FM decreased pre to post in NI (11.5 ± 4.8 vs. 10.5 ± 5.4 kg) but not C (11.3 ± 4.7 vs. 11.9 ± 4.5 kg). FFM increased pre to post with no differences between groups. The 5-10-5 shuttle times decreased significantly more in NI (4.58 ± 0.15 vs. 4.43 ± 0.13 sec) compared to C (4.56 ± 0.18 vs. 4.50 ± 0.16 sec). Jump and squat performance increased pre to post with no differences between groups. Our findings indicate that an off season SNEI is effective at improving sport nutrition knowledge and some, but not all, nutrient intakes and performance measures in Division I baseball players.
Sherwin, Jason; Muraskin, Jordan; Sajda, Paul
Hitting a baseball is often described as the most difficult thing to do in sports. A key aptitude of a good hitter is the ability to determine which pitch is coming. This rapid decision requires the batter to make a judgment in a fraction of a second based largely on the trajectory and spin of the ball. When does this decision occur relative to the ball’s trajectory and is it possible to identify neural correlates that represent how the decision evolves over a split second? Using single-trial analysis of electroencephalography (EEG) we address this question within the context of subjects discriminating three types of pitches (fastball, curveball, slider) based on pitch trajectories. We find clear neural signatures of pitch classification and, using signal detection theory, we identify the times of discrimination on a trial-to-trial basis. Based on these neural signatures we estimate neural discrimination distributions as a function of the distance the ball is from the plate. We find all three pitches yield unique distributions, namely the timing of the discriminating neural signatures relative to the position of the ball in its trajectory. For instance, fastballs are discriminated at the earliest points in their trajectory, relative to the two other pitches, which is consistent with the need for some constant time to generate and execute the motor plan for the swing (or inhibition of the swing). We also find incorrect discrimination of a pitch (errors) yields neural sources in Brodmann Area 10, which has been implicated in prospective memory, recall, and task difficulty. In summary, we show that single-trial analysis of EEG yields informative distributions of the relative point in a baseball’s trajectory when the batter makes a decision on which pitch is coming. PMID:23267311
Braverman, P K; Strasburger, V C
Adolescents are becoming sexually active at younger ages. One half of the adolescents in the United States are sexually active. This article reviews adolescent sexual activity, including rates of sexual activity, sexual practices, gay and lesbian youth, and factors affecting the initiation of sexual activity. In addition, adolescent pregnancy, with possible outcomes and effects on teen parents and their offspring, is discussed.
The Effects of a Sports Nutrition Education Intervention on Nutritional Status, Sport Nutrition Knowledge, Body Composition, and Performance during Off Season Training in NCAA Division I Baseball Players
Rossi, Fabrício Eduardo; Landreth, Andrew; Beam, Stacey; Jones, Taylor; Norton, Layne; Cholewa, Jason Michael
This study investigated the effects of a sport nutrition education intervention (SNEI) on dietary intake, knowledge, body composition, and performance in NCAA Division I baseball players. Resistance trained NCAA Division I baseball players (82.4 ± 8.2 kg; 1.83 ± 0.06 m; 13.7 ± 5 % body fat) participated in the study during 12 weeks of off-season training. Fifteen players volunteered for SNEI while 15 players matched for position served as controls (C) for body composition and performance. The nutrition intervention group (NI) received a 90 min SNEI encompassing energy intake (Kcal), carbohydrate (CHO), protein (PRO), fat, food sources, and hydration. Sport nutrition knowledge questionnaires were administered to NI pre and post. Nutritional status was determined by three-day dietary logs administered to NI pre and post. Body composition and performance (5-10-5 shuttle test, vertical jump, broad jump, 1 RM squat) were measured pre and post for C and NI. Knowledge increased in NI. Pro and fat, but not CHO intake increased in NI. FM decreased pre to post in NI (11.5 ± 4.8 vs. 10.5 ± 5.4 kg) but not C (11.3 ± 4.7 vs. 11.9 ± 4.5 kg). FFM increased pre to post with no differences between groups. The 5-10-5 shuttle times decreased significantly more in NI (4.58 ± 0.15 vs. 4.43 ± 0.13 sec) compared to C (4.56 ± 0.18 vs. 4.50 ± 0.16 sec). Jump and squat performance increased pre to post with no differences between groups. Our findings indicate that an off season SNEI is effective at improving sport nutrition knowledge and some, but not all, nutrient intakes and performance measures in Division I baseball players. Key points Sport nutrition education intervention increased nutritional knowledge and nutritional status. Sport nutrition education intervention reduced body fat percentage, total fat mass, 5-10-5 shuttle times, and trended towards greater increases in lean mass compared to controls. Both groups increased strength and jump ability similarly. PMID:28344452
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