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David Whiteside, Douglas N. Martini, Ronald F. Zernicke and Grant C. Goulet

Purpose:

With a view to informing in-game decision making as it relates to strategy and pitcher health, this study examined changes in pitching-performance characteristics across 9 innings of Major League Baseball (MLB) games.

Methods:

129 starting MLB pitchers met the inclusion criteria for this study. Pitch type, speed, ball movement, release location, and strike-zone data—collected using the MLB’s ball-tracking system, PITCHf/x—were obtained for 1,514,304 pitches thrown from 2008 to 2014.

Results:

Compared with the 1st inning, the proportion of hard pitches thrown decreased significantly until the 7th inning, while the proportions of breaking and off-speed pitches increased. Significant decreases in pitch speed, increases in vertical movement, and decreases in release height emerged no later than the 5th inning, and the largest differences in all variables were generally recorded between the 1st inning and the late innings (7–9). Pitchers were most effective during the 2nd inning and significantly worse in innings 4 and 6.

Conclusion:

These data revealed that several aspects of a starting pitcher’s pitching characteristics exhibited changes from baseline as early as the 2nd or 3rd inning of an MLB game, but this pattern did not reflect the changes in his effectiveness. Therefore, these alterations do not appear to provide reasonable justification for relieving a starting pitcher, although future work must address their relevance to injury. From an offensive standpoint, batters in the MLB should anticipate significantly more hard pitches during the early innings but more breaking and off-speed pitches, with decreasing speed, as the game progresses.

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Arnel L. Aguinaldo, Janet Buttermore and Henry Chambers

High rotational torques during baseball pitching are believed to be linked to most overuse injuries at the shoulder. This study investigated the effects of trunk rotation on shoulder rotational torques during pitching. A total of 38 pitchers from the professional, college, high school, and youth ranks were recruited for motion analysis. Professional pitchers demonstrated the least amount of rotational torque (p = .001) among skeletally mature players, while exhibiting the ability to rotate their trunks significantly later in the pitching cycle, as compared to other groups (p = .01). It was concluded that the timing of their rotation was optimized as to allow the throwing shoulder to move with decreased joint loading by conserving the momentum generated by the trunk. These results suggest that a specific pattern in throwing can be utilized to increase the efficiency of the pitch, which would allow a player to improve performance with decreased risk of overuse injury.

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Kamiel Reid and Christine Dallaire

( Foucault, 1977 , 1982 ). Drawing on this theoretical framework, we focus on the concepts of discourse, subject and power to examine the ways in which the women described their experiences on the soccer pitch. That is, we explore social (discursive) practices and actions ( Foucault, 1977 ) that constitute

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Adam Jones, Richard Page, Chris Brogden, Ben Langley and Matt Greig

-tibia. Methods Design The study was a repeated-measures design. To increase the ecological validity of our study, all analyses were conducted on regulation soccer pitches. Three experimental trials were completed in a randomized order, dictated by playing surface: natural turf (Grass), second-generation “astro

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Jeffery J. Summers, Winston D. Byblow, Don F. Bysouth-Young and Andras Semjen

Seven right-handed participants performed bimanual circling movements in either a symmetrical or an asymmetrical coordination mode. Movements were paced with an auditory metronome at predetermined frequencies corresponding to transition frequency, where asymmetrical patterns became unstable, or at two-thirds transition frequency, where both symmetrical and asymmetrical patterns were stable. The pacing tones were presented in either a high (1000 Hz) or low (500 Hz) pitch, and the percentage of high-pitched tones during a 20 s trial varied between 0% and 70%. Participants were instructed to count the number of high-pitched pacing tones that occurred during a trial of bimanual circling. Overall, the symmetrical pattern was more stable than the asymmetrical pattern at both frequencies. Errors on the tone-counting task were significantly higher during asymmetrical circling than symmetrical circling but only at the transition movement frequency. The results suggest that cognitive processes play a role in maintaining coordination patterns within regions of instability.

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Matt Greig and Benjamin Child

to reduce injury risk. Methods Design The study was a repeated-measures design. To increase the ecological validity of our study, all analyses were conducted on a regulation cricket pitch with participants tested in a single session. The number of approach strides in each delivery and the location of

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Paola Rodriguez-Giustiniani, Ian Rollo, Oliver C. Witard and Stuart D. R. Galloway

stretches, and 20-m sprints), before completing the 90-min SMS protocol ( Russell et al., 2011 ) followed by a high-intensity (90% VO 2 max) running test to exhaustion. All testing sessions were performed on an indoor artificial grass pitch. Experimental Trials Experimental trials were scheduled to start in

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Fang Zhang and Nandini Deshpande

Fifteen young (20–30 years old) and 15 older (>65 years old) healthy participants were recruited to investigate age-related differences in head and trunk control under suboptimal vestibular conditions (galvanic vestibular stimulation, or GVS) and vision conditions during normal and narrow-based walking. Head-roll velocity decreased in the blurred-vision condition and marginally increased with GVS in older but not in young participants. Head pitch increased, whereas head-roll velocity decreased in narrow-base walking. Trunk pitch, trunk-pitch velocity, and gait speed increased with GVS, whereas trunk-pitch velocity and gait speed decreased in narrow-base walking. Marginally increased head-roll velocity in the older participants possibly suggests decreased integrative ability of the central nervous system in elderly people. The changes in head control during narrow-base walking may be an attempt to simplify the interpretation of the vestibular signal and increase otolith sensitivity. The complexity of controlling the trunk in the mediolateral direction was suggested by different strategies used for trunk control in different conditions.

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Mont Hubbard and LeRoy W. Alaways

Changes in the rules for construction of the men's javelin have dramatically altered the pitching moment profile as a function of angle of attack. Thus the optimal release conditions are different for the new javelin. Optimal release conditions are presented for nominal release velocities in the range 20 < vn < 35 m/s. Although the optimal release angle remains roughly constant near 30° over this speed range, the optimal angle of attack and pitching angular velocity change substantially with speed. The main effects of the rule change have been (a) to decrease the achievable range at a nominal velocity vn = 30 m/s by about 10% by making it impossible to take advantage of the javelin's potentially large aerodynamic lift forces, and (b) to make the flight much less sensitive to initial conditions.

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Rob Gray

Although it is commonly believed that focusing too much attention on the injured body area impairs recovery in sports, this has not been directly assessed. The present study investigated attentional focus following sports injury. Experienced baseball position players recovering from knee surgery (Expt 1) and baseball pitchers recovering from elbow surgery (Expt 2) performed simulated batting and pitching respectively. They also performed three different secondary tasks: leg angle judgments, arm angle judgments, and judgments about the ball leaving their bat/hand. Injured athletes were compared with expert and novice control groups. Performance on the secondary tasks indicated that the injured batters had an internal focus of attention localized on the area of the injury resulting in significantly poorer batting performance as compared with the expert controls. Injured pitchers had a diffuse, internal attentional focus similar to that of novices resulting in poorer pitching performance as compared with the expert controls.