The purpose of this study was to investigate the relationship of six selected volleyball skill tests to actual volleyball game performance. The six skill test items were administered to 64 subjects, who were all members of a college level introductory volleyball course. Based on the ratings of a panel of experts, subjects were rated during game play as good, average, or poor performers. The stepwise discriminant analysis was used to analyze the relationship between skill tests and game performance. Four of the six skill tests were identified as significantly contributing to group membership. These tests, in order of the magnitude of their standardized discriminant function coefficients were: 1. Brumbach Serve Test, 2. AAHPER Wall Volley test, 3. AAHPERD Wall Spike Test, and 4. AAHPERD Serve Test. It was concluded that a volleyball skill test battery consisting of these four items would objectively measure volleyball playing ability and discriminate between players of various skill levels. The results of this test battery could be used for classification, diagnosis, motivational purposes, and grading.

Anterior cruciate ligament (ACL) ruptures are one of the most common knee ligament injuries suffered by both male and female athletes. These injuries are severe in nature and also have long-term impacts on activities of daily living. Significant research has been conducted utilizing a drop landing task to attempt to better understand the mechanics behind the injury and to help identify at-risk athletes for targeted intervention. However, there have not been any published standards for the height of the drop landing activity, and previous researchers have also raised some concerns about the ability of a drop landing task to replicate the landing mechanics of a sport-specific task. To examine possible differences in performance based on specific landing tasks, the first study compared the landing mechanics of male and female high school athletes in three different landing conditions (drop landing, DL; adjusted height drop landing, AHDL; and a vertical jump task, VJL) (Chapter 3). Thirty-seven (37) athletes completed bilateral landings in the three conditions, and their kinetic and kinematic landing mechanics were compared across conditions. For the male participants, maximum knee flexion during landing was greater in AHDL condition as compared to the DL and VJL conditions. Both male and female participants demonstrated greater hip adduction at impact and overall maximum value in the VJL condition as compared to the two drop landings. As drop landing tasks have been used to identify at-risk athletes, it was important to examine the three different tasks’ ability to predict lower extremity ligamentous injuries, and whether those 3D motion analysis predictors were more precise than a quick clinical symmetry screening tool (Chapter 4). One-hundred-and-sixty-five (165) athletes completed the clinical symmetry screen, and a subgroup of thirty-seven (37) athletes completed the 3D motion analysis. All of these participants were surveyed for lower extremity ligamentous injuries over the course of a season. Due to a small number of reported injuries, none of the injury predictor models based on 3D motion analysis landing mechanics or the clinical symmetry screening tool were able to produce accurate predictor models of injury. Knee abduction moment has been shown to be one of the strongest predictors of ACL injuries, and due to the collection of bilateral kinetics for a previous study (Chapter 3), there was a need to examine differences in KAM between the three different landing tasks (Chapter 5). Ten (10) recreational athletes completed bilateral landings in the three conditions, with foot placement relative to force plates to enable KAM calculation. The participants did not demonstrate any difference in KAM between the three landing conditions; however, a test for constant variance showed that the AHDL resulted in significantly less variance in KAM than DL or VJL. The results of these studies suggest that while easy to standardize, a set height drop landing task does not produce identical landing mechanics to those from an adjusted height drop landing task or a vertical jump task. Further research is needed to create or justify standardized landing tasks for researchers to utilize that produce consistent results that best duplicate the landing mechanics athletes performed during sporting activities. While the landing mechanics demonstrated in the three tasks and the results from the clinical screening were not able to predict injuries, future studies should examine quick clinical screening tools to identify athletes at a high risk of injury.

The purpose of this dissertation is to better understand the role of repeated-sprint ability (RSA) and resulting fatigue in cyclists; how it relates to measures of aerobic power and strength and power performance indices- due to the nature of cycling competitions and the necessity of RSA for success. The first part of this dissertation attempted to elucidate the relationship between RSA and aerobic power and strength/ power measures in competitive cyclists. The purpose was to potentially illustrate the importance of the inclusion of strength and power training in the training regimen of cyclists. The findings showed several statistically significant relationships between variables of RSA and aerobic power or the isometric squat test. The second part of the dissertation examined the effects of fatigue induced from the acute bout of repeat sprint exercise on strength and power measures in three different recovery periods. It is commonplace for cyclists to have several heats in one day of racing. Examining the effects of fatigue on strength measures such as peak force and rate of force development could begin to delineate how an individual experiences fatigue based on their own characteristics, enabling them to design a training program to address these strengths/ weaknesses to optimize performance and decrease fatigue. The results from a repeated measures analysis of variance found no statistically significant effect on PF or RFD. Additional comparisons showed moderate effects of fatigue on RFD throughout the three post-RSE trials. There was also a moderate correlation between the RSE fatigue % decrement score and the isometric RFD fatigue % decrement score. What we may conclude from this dissertation is that fatigue has various causes and can vary with an individuals’ unique physiology and how they respond to performance variables on any specific day can vary. Development of increased strength and subsequent power, or “explosive strength”, may have advantages in competitive cycling. Coupling proper strength and power training with an aerobic training regimen, may greatly benefit the athlete by increasing their peak power output, economy of movement, delaying fatigue, improving anaerobic capacity, and overall enhancing their maximal speed.

Branched-chain amino acid (BCAA) supplementation may improve recovery from competitive endurance training by reducing symptoms of central and peripheral fatigue. The purpose of this dissertation was to provide evidence for the use of BCAAs as a training nutrition strategy in order to improve recovery from training and further drive adaptive processes to training by increasing readiness to train. Collegiate distance runners undergoing intense competitive endurance training were monitored for symptoms of muscular soreness and psychological stress through a rated soreness chart and the Daily Analysis of Life Demands for Athletes Survey (DALDA) while taking either a BCAA supplement or a placebo. When on the BCAA supplement, athletes reported significantly fewer symptoms of psychological stress and reduced muscular soreness. These results point to the importance of nutrient bioavailability, specifically BCAAs, on recovery parameters when undergoing intensive training. This concept was also demonstrated in a case study on a trained distance runner who underwent intensive training for an ultra-endurance marathon. Running kinematics were assessed using Kinovea open-sourced software (Version 0.8.15) during a series of constant-paced endurance runs while on the BCAA supplement or a placebo. We observed a reduction in vertical oscillation when the runner was on the BCAA supplement, indicating improved muscle recovery and therefore efficiency of movement. Improving recovery by reducing global central and peripheral fatigue symptoms may increase readiness to train and further promote desired training adaptations.

The case study highlights the evaluation of one campus recreation center in terms of its inclusive design and operation on the basis of physical disability inclusion. Because of the plethora of barriers in campus recreation centers, those with physical disabilities are limited in their recreation choices and do not take part in recreation as their able-bodied counterparts. This study measures, observers, and evaluates one campus recreation center to determine its level of inclusiveness for those with physical disabilities. The AIMFREE survey was conducted along with observations and extensive interviews with staff that run the campus recreation center and those with physical disabilities that have attended the recreation facility. Results from six interviews, a focus group, the AIMFREE survey, and observations have yielded four main themes. The environment lacks inclusivity that results from financial, attitudinal, and social barriers. Attitudinal barriers to inclusivity occur at three main levels: administration, the staff and users of the facility. As a result, the recreation center is also not socially constructed for inclusivity. The goal of this research is to create change in the studied setting. As a result of investigating inclusivity at one recreation center, several areas of improvement emerged and can be used to implement change at campus recreation centers alike.

The purpose of this dissertation was to explore the physical and technical demands of the women’s college soccer game through a case study approach. With advancements in technology, motion analysis has become commonplace in most professional environments. However, the literature on amateur soccer is quite scarce and warrants more attention. The aims of this dissertation were: 1) to describe the physical demands of each position for a women’s college soccer player as they relate to total distance covered, efforts, and distance covered in high-speed velocity bands, 2) explore the variation in physical performance during a competitive season, and 3) compare the physical and technical performance of college soccer players to see if there are correlates in performance between variables. Eleven female collegiate soccer players from a single National Collegiate Athletic Association (NCAA) institution were tracked with Global Position System devices during a competitive season. Physical variables and technical variables were analyzed to gain further insight into the specific events that occur during a women’s college soccer match. Significant differences exist between positions for total distance covered during a match, with the forward and central defensive midfielder position covering the greatest distance during a match on average. The central defender position covered a significantly less amount of distance during a match than the other five positional subcategories. Outside players (forward, outside midfielder, and fullback) covered the greatest distance at high-speed velocity bands and perform the highest volume of high-speed efforts. The only significantly different technical variable found was the pass completion percentage of the central defensive midfielder compared with other positions. The current investigation highlights the unique characteristics of female collegiate soccer players when separated and analyzed by the positional subcategories. With uniqueness present in a once thought to be homogenous population the demand for individualized training protocols becomes paramount to increase chance of optimal performance while simultaneously decreasing risk of injury.

Objective: To explore currently accepted return-to-play tests and a jumps protocol in a single subject design following anterior cruciate ligament reconstruction. Background: The subject sustained 2 ruptures of the ACL in the left knee in a 12-month period. Both events were noncontact injuries occurring on the landing phase of a jump. A physical exam and magnetic resonance imaging were performed for both injuries by multiple orthopedic surgeons in the United States (1st rupture) and in Brazil (1st & 2nd rupture) to diagnose the injury. Treatment: Following the initial injury the subject attended 2 rehabilitation sessions per week for 16 weeks with an outpatient physical therapy clinic in the US. After the second surgery the athlete returned to the US and received treatment 6 days per week for 8 months with the University sports medicine staff. Return-to-play testing: Along with the hop test and an isokinetic knee flexion/extension test as a general protocol to determine the return-to-play, a jumps protocol to assess bilateral asymmetry and performance was also used. The symmetry index score (SI) was used to evaluate the magnitude of asymmetry. Conclusions: Following ACL reconstruction, objective data from the Hop Test, Isokinetic Test and Jumps Protocol can assist the healthcare provider in determining return-to-play status.

The purposes of this dissertation were to examine bilateral asymmetry as a factor of postactivation potentiation, examine and compare the acute effects of ballistic and non-ballistic concentric-only half-squats on squat jump performance, and compare the potentiation and temporal profiles of strong and weak subjects following potentiation protocols that included ballistic and non-ballistic concentric-only half-squats. The following are major findings of the dissertation. Squat jump performance may be acutely enhanced following ballistic concentriconly half-squats; however the changes in performance do not appear to be related to bilateral symmetry. Ballistic concentric-only half-squats acutely improve various squat jump performance variables at various time intervals; however the changes in performance are not related to the bilateral symmetry of the subject. Ballistic concentric-only half-squats produced superior acute potentiation effects with regard to jump height, peak power, and allometricallyscaled peak power as compared to non-ballistic concentric-only half-squats and a control protocol. Stronger subjects potentiated earlier and to a greater extent as compared to their weaker counterparts. This dissertation indicates that bilateral symmetry may not be considered as an underlying factor affecting postactivation potentiation. However, it is suggested that future research should continue to investigate the factors that are associated with postactivation potentiation. The findings of this dissertation also demonstrate the importance of how an individual performs a concentric-only squatting motion. By training with ballistic movements, a greater training stimulus may be achieved as compared to training with non-ballistic movements. While this dissertation discussed the acute potentiation differences between ballistic and nonballistic concentric-only half-squats, longitudinal research is needed to determine if different training effects result from each training method. This dissertation also supports that notion that stronger individuals may benefit more with regard to potentiation effects. In order to optimize performance and realize the greatest potentiation effects, it is recommended that greater levels of relative strength should be sought. It is suggested that further research is needed on the longitudinal differences in the potentiation effects an individual can realize based on their strength levels.

The purpose of this dissertation was to investigate the influence of lower body strength characteristics on change of direction (COD) performance in NCAA Division I soccer athletes. Specifically, this dissertation served to examine: 1) whether the lower body strength and power were related to COD performance, 2) whether stronger athletes had superior COD performance than weaker athletes, 3) whether the force production asymmetry and strength dominant (SD) associated with COD performance, and 4) weather sex differences existed in kinetic variables during the stand phase of cutting. The major findings of this dissertation include: 1) strength and power characteristics were moderately to strongly related to COD performance. Furthermore, soccer athletes’ straight-line sprinting times were significantly related to COD performance outcomes. 2) Stronger athletes demonstrated the tendency to perform superiorly in modified 505 COD test when compared to weaker athletes. 3) Athletes who had more lower body force production asymmetry were more likely to perform asymmetrically during a COD test. However, the SD and the magnitude of asymmetry were not limiting factors for athletes’ COD performance.4) Male athletes demonstrated statistically significantly less COD total time, longer ground contact time (GCT), and better ability to apply forces and impulses while performing cutting. Based on the results, vertical forces and impulses during both the braking and propulsive phases of cutting ranged from 2.51 to 3.14 times larger than horizontal direction. In summary, stronger and more powerful soccer athletes were able to perform in a superior manner for both the COD tasks and straight-line sprinting. This may be due to the ability to produce high force and power during the critical time periods. Although force production asymmetry during related to the asymmetrical performance during COD tasks, the SD and the magnitude of asymmetry did not limit the COD performance. Finally, statistical differences existed between sexes in kinetic variables during cutting may be due to the different approaches to apply force in this task. Moreover, the ability to generate higher force and impulse in the vertical direction could affect COD performance.

In an attempt to demonstrate the interconnecting nature of the pillars of sport (Hacker, 2000) this thesis explores the relationship between physical, psychological and technical variables. Five National Collegiate Athletic Association (NCAA) Division I Women’s Soccer players were analyzed in four conference matches. The athlete's rate of perceived exertion (RPE) values were correlated to pass completion percentages (PC%) to investigate the potential effect that psychological satisfaction or dissatisfaction of technical performance has on perceived exertion ratings. PlayerLoadTM (PL) values, gathered through the utilization of a Catapult Minimax S4 GPS device (miniMax-10 Hz, Catapult Innovations, Melbourne, Australia), were used as a measure of actual workload in order to determine the accuracy of perceived exertion ratings. Results exhibited a trivial correlation (r = 0.028) and large variability (R2 = 0.00077) between RPE and PC% in comparison to PL and PC% (r = 0.50; R2 = 0.2502). The results indicate that an athlete's PC% does not correspond to how physically demanding they perceived a match to be. However, it is possible that performance variables may influence the RPE ratings a player provides.