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Stephen J. Page, Wesley Sime and Kelly Nordell

Some athletes perceive competitive anxiety as negative and detrimental to performance while it invigorates and excites others. Since perceptions of anxiety impact motor performance, it is important to develop techniques by which perceptions can be modified. The aims of this study were to determine the efficacy of a single imagery session in: (a) modifying perceptions of anxiety from negative to positive, and (b) reducing precompetitive state anxiety levels. Using a switched replication design, Murray’s (1989) Competitive Anxiety Perception Scale (CAPS) and the Competitive State Anxiety Inventory-2 (CSAI-2) (Martens, Burton, Vealey, Bump, & Smith, 1990) were administered to 40 female intercollegiate swimmers weekly over the course of 5 weeks. Following random exposure to imagery, nonsignificant changes on the scales of the CSAI-2 (cognitive [F{1, 39} = .30, p > .05], somatic [F{1, 39} = 0.72, p > .05], self-confidence [F{1, 39} = 2.93, p > .05]), and significant improvements on the CAPS as positive (F[1, 39] = 19.60, p < .01) were observed. Results suggest that perceptions of anxiety may be modified by imagery, which could aid performance.

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Marshall Magnusen, Andrew Gallucci, Stephen Kelly and Josh Brown

This case is a creative illustration of organizational politics in a National Collegiate Athletics Association (NCAA) sports setting. It includes the exploration of several key concepts: political will, political skill, political perceptions, political behavior, and political influence theory. Upon arriving to his new job at the Division I level, an assistant men’s basketball coach finds himself to be a key piece in a political chess match between the highly successful Head Coach of the men’s basketball team and the Athletic Director (AD). The issue at hand is the hiring of the new assistant coach by the AD without the support of the head coach. The hire is an attempt by the AD to subvert and eventually replace the legendary head coach who, in the eyes of the AD, is long past his prime. Accordingly, the new hire encounters a variety of political scenarios, including strong resistance from the players and coaching staff of the men’s basketball team. This case, with the addition of detailed teaching notes, is designed to highlight salient elements of organizational politics to undergraduate and graduate sport management students, and explain how they can successfully apply this information and more effectively operate in the political sports arena.

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Catherine J. Vladutiu, Kelly R. Evenson and Stephen W. Marshall

Background:

Although physical activity can provide health benefits to pregnant women, population-based research on the circumstances surrounding injuries from physical activity during pregnancy is lacking.

Methods:

Physical activity and subsequent injuries among a cohort of 1469 pregnant women in North Carolina were examined prospectively from the third phase of the Pregnancy, Infection, and Nutrition Study between 2001 and 2005. Chi-square analyses were used to compare distributions of maternal characteristics among women who sustained injuries from physical activity and women who reported no injuries during pregnancy. Injury incidence rates were calculated.

Results:

Few pregnant women (N = 34) reported a physical activity-related injury during pregnancy. The rates of physical activity-related and exercise-related injuries during pregnancy were 3.2 per 1000 physical activity hours and 4.1 per 1000 exercise hours, respectively. The most common types of injuries were bruises or scrapes (55%). Among all injuries, 33% resulted from exercise and 67% resulted from nonexercise physical activities. Sixty-four percent of all injuries were due to falls.

Conclusions:

The incidence of injury from physical activity was low during pregnancy. Women should continue to be encouraged to maintain involvement in physical activity during pregnancy, while being aware of the potential for injury, particularly falls, from these activities.

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Matthew David Cook, Stephen David Myers, John Stephen Michael Kelly and Mark Elisabeth Theodorus Willems

Impaired glucose tolerance was shown to be present 48 hr following muscle-damaging eccentric exercise. We examined the acute effect of concentric and muscle-damaging eccentric exercise, matched for intensity, on the responses to a 2-hr 75-g oral glucose tolerance test (OGTT). Ten men (27 ± 9 years, 178 ± 7 cm, 75 ± 11 kg, VO2max: 52.3 ± 7.3 ml·kg-1·min-1) underwent three OGTTs after an overnight 12 hr fast: rest (control), 40-min (5 × 8-min with 2-min interbout rest) of concentric (level running, 0%, CON) or eccentric exercise (downhill running, –12%, ECC). Running intensity was matched at 60% of maximal metabolic equivalent. Maximal isometric force of m. quadriceps femoris of both legs was measured before and after the running protocols. Downhill running speed was higher (level: 9.7 ± 2.1, downhill: 13.8 ± 3.2 km·hr-1, p < .01). Running protocols had similar VO2max (p = .59), heart rates (p = .20) and respiratory exchange ratio values (p = .74) indicating matched intensity and metabolic demands. Downhill running resulted in higher isometric force deficits (level: 3.0 ± 6.7, downhill: 17.1 ± 7.3%, p < .01). During OGTTs, area-under-the-curve for plasma glucose (control: 724 ± 97, CON: 710 ± 77, ECC: 726 ± 72 mmol·L-1·120 min, p = .86) and insulin (control: 24995 ± 11229, CON: 23319 ± 10417, ECC: 21842 ± 10171 pmol·L-1·120 min, p = .48), peak glucose (control: 8.1 ± 1.3, CON: 7.7 ± 1.2, ECC: 7.7 ± 1.1 mmol·L-1, p = .63) and peak insulin levels (control: 361 ± 188, CON: 322 ± 179, ECC: 299 ± 152 pmol·L-1, p = .30) were similar. It was concluded that glucose tolerance and the insulin response to an OGTT were not changed immediately by muscle-damaging eccentric exercise.

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Stephen John Thomas, Charles B. Swanik, Kathleen Swanik and John D. Kelly

Context:

Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal-rotation (IR) motion and concurrent increases in external-rotation (ER) motion. In addition, alterations to scapular upward rotation have been identified in this population.

Objective:

To measure glenohumeral (GH) IR and ER rotation, total range of motion (ROM), and scapular upward rotation throughout the course of a Division I collegiate baseball season.

Design:

Pretest to posttest study.

Setting:

Controlled laboratory setting.

Participants:

Thirty-one collegiate baseball players with no current shoulder or elbow injury completed this study.

Intervention:

Participants were measured for all dependent variables at preseason and postseason.

Main Outcome Measures:

GH IR and ER were measured supine with the scapula stabilized. Total GH ROM was calculated as the sum of IR and ER measures. Scapular upward rotation was tested at rest, 60°, 90°, and 120° of GH abduction in the scapular plane.

Results:

Overall, the dominant arm had significantly less GH IR and significantly more ER than the nondominant arm. The total motion on the dominant arm was significantly less than on the nondominant arm. No significant differences were observed from preseason to postseason for IR, ER, or total motion. Dominant-arm scapular upward rotation significantly decreased at 60°, 90°, and 120° of abduction from preseason to postseason.

Conclusion:

Collegiate baseball players presented with significant GH-motion differences (decreases in IR and increases in ER) in their dominant arm compared with their nondominant arm. There was also significantly less total motion on the dominant arm. After 12 wk of competitive Division I collegiate baseball, there were significant decreases in upward rotation over the season.

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Stephen J. Thomas, Kathleen A. Swanik, Charles “Buz” Swanik, Kellie C. Huxel and John D. Kelly IV

Context:

Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal rotation (IR) and concurrent increases in external rotation (ER). In addition, alterations to scapular position have been identified in this population, but the chronology of these adaptations is uncertain.

Objectives:

To determine whether there is a change in range of motion and scapular position after a single baseball season.

Design:

Prospective cohort.

Setting:

High school.

Participants:

19 high school baseball players (age 16.6 ± 0.8 y, mass 78.6 ± 12.0 kg, height 180.3 ± 6.2 cm).

Interventions:

Subjects were measured for all dependent variables at preseason and postseason.

Main Outcome Measures:

Participants were measured for glenohumeral (GH) IR and ER with the scapula stabilized. Total GH range of motion was calculated as the sum of IR and ER. Scapular upward rotation was measured at 0°, 60°, 90°, and 120° of GH abduction in the scapular plane, and scapular protraction, at 0°, hands on hips, and 90° of GH abduction.

Results:

Overall, the dominant arm had significantly less GH IR (11.4°, P = .005) and significantly more ER (4.7°, P = .001) than the nondominant arm. Total motion in the dominant arm was significantly less than in the nondominant arm (6.7°, P = .001). Scapular upward rotation in the dominant arm significantly increased at 0° (2.4°, P = .002) and significantly decreased at 90° (3.2°, P = .001) and 120° (3.2°, P < .001) of abduction from preseason to postseason. Scapular protraction in the nondominant arm significantly decreased at 45° (0.32 cm, P = .017) and 90° (0.33 cm, P = .006) from preseason to postseason.

Conclusion:

These data suggest that scapular adaptations may be acquired over a relatively short period (12 wk) in a competitive baseball season. Competitive high school baseball players also presented with significant GH motion differences between their dominant and nondominant arms. Total motion was also significantly less in the dominant arm than in the nondominant arm.

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Stephen J. Kelly, Aron J. Murphy, Mark L. Watsford, Damien Austin and Michael Rennie

Purpose:

To investigate the validity and reliability of accelerometry of the SPI-ProX II dual data logger (GPSports, Canberra, Australia).

Methods:

Controlled laboratory assessments determined the accuracy and reproducibility of raw accelerometer data. Intra- and interdevice reliability assessed the ability of the SPI-ProX II accelerometers to repeatedly measure peak gravitational accelerations (g) during impact-based testing. Static and dynamic validity testing assessed the accuracy of SPI-ProX II accelerometers against a criterion-referenced accelerometer. Dynamic validity was assessed over a range of frequencies from 5 to 15 Hz.

Results:

Intradevice reliability found no differences (P < .05) between 4 SPI-ProX II accelerometers, with a low coefficient of variation (1.87–2.21%). SPI-ProX II accelerometers demonstrated small to medium effect-size (ES) differences (0.10–0.44) between groups and excellent interdevice reliability, with no difference found between units (F = 0.826, P = .484). Validity testing revealed significant differences between devices (P = .001), with high percentage differences (27.5–30.5%) and a large ES (>3.44).

Conclusions:

SPI-ProX II accelerometers demonstrated excellent intra- and interaccelerometer reliability. However, static and dynamic validity were poor, and caution is recommended when measuring the absolute magnitude of acceleration, particularly for high-frequency movements. Regular assessment of individual devices is advised, particularly for mechanical damage and signal-drift errors. It is recommended that guidelines be provided by the manufacturer on measuring shifts in the base accelerometer signal, including time frames for assessing accelerometer axis, magnitude of errors, and calibration of accelerometers from a stable reference point.

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Kathleen A. Swanik, Stephen J. Thomas, Aaron H. Struminger, Kellie C. Huxel Bliven, John D. Kelly and Charles B. Swanik

Context:

Plyometric training is credited with providing benefits in performance and dynamic restraint. However, limited prospective data exist quantifying kinematic adaptations such as amortization time, glenohumeral rotation, and scapulothoracic position, which may underlie the efficacy of plyometric training for upper-extremity rehabilitation or performance enhancement.

Objective:

To measure upper-extremity kinematics and plyometric phase times before and after an 8-wk upper-extremity strength- and plyometric-training program.

Design:

Randomized pretest–posttest design.

Setting:

Research laboratory.

Participants:

40 recreationally active men (plyometric group, age 20.43 ± 1.40 y, height 180.00 ± 8.80 cm, weight 73.07 ± 7.21 kg; strength group, age 21.95 ± 3.40 y, height 173.98 ± 11.91 cm, weight 74.79 ± 13.55 kg).

Intervention:

Participants were randomly assigned to either a strength-training group or a strength- and plyometric-training group. Each participant performed the assigned training for 8 wk.

Main Outcome Measures:

Dynamic and static glenohumeral and scapular-rotation measurements were taken before and after the training programs. Dynamic measurement of scapular rotation and time spent in each plyometric phase (concentric, eccentric, and amortization) during a ball-toss exercise were recorded while the subjects were fitted with an electromagnetic tracking system. Static measures included scapular upward rotation at 3 different glenohumeral-abduction angles, glenohumeral internal rotation, and glenohumeral external rotation.

Results:

Posttesting showed that both groups significantly decreased the time spent in the amortization, concentric, and eccentric phases of a ball-toss exercise (P < .01). Both groups also exhibited significantly decreased static external rotation and increased dynamic scapular upward rotation after the training period (P < .01). The only difference between the training protocols was that the plyometric-training group exhibited an increase in internal rotation that was not present in the strength-training group (P < .01).

Conclusion:

These findings support the use of both upper-extremity plyometrics and strength training for reducing commonly identified upper-extremity-injury risk factors and improving upper-extremity performance.