xiii, 89 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Participation in athletics includes an inherent risk of becoming injured that is related to the nature of the games and activities of the players. Current literature reports that approximately seven million high school students participate in sports yearly in the United States and, during the 2005-2006 sport seasons, 1.4 million injuries were reported. Considering this high number of injuries, there is little doubt that definitive research into the determination of factors that might help predict the degree of injury risk associated with sport participation is warranted. Despite common association of variables such as joint laxity, range of motion, strength and balance with injury, these traditional measures have not proven to be reliable predictors of vulnerability. Consequently, attempts have been made to identify practical methods that may better permit identification of individuals who show a high likelihood of injury during athletic competition. This study examined one such system, the Functional Movement Screen (FMS), which utilizes measures of mobility and stability to permit its developers to assert that it can be used to practically and accurately identify vulnerable athletes. Critical data on inter-rater and intra-rater performance were first obtained on a team of athletic trainers to ensure that they could reliably execute the testing methods. Following confirmation of this fact, 112 high school basketball athletes were screened with the FMS and their injuries (non-contact neuromusculoskeletal tissue damage in school-sanctioned basketball) were tracked throughout an entire season. Data analysis to determine if a commonly-used FMS cutoff score of less than 14 out of 21 could identify vulnerable athletes revealed that this value was not significantly related to the likelihood of sustaining an injury. Furthermore, logistic regression revealed that none of the individual predictors (gender, FMS movements, and movement asymmetries) were significant predictors of injury susceptibility. The results indicate that, despite the fact that multiple evaluators and trials can be practically used to evaluate FMS scores in a large group of high school basketball athletes, the test does not appear to be a valid tool in assessing injury risk in this population during an entire season. / Committee in charge: Gary Klug, Chairperson, Human Physiology; Paul van Donkelaar, Member, Human Physiology; Andrew Lovering, Member, Human Physiology; Roland Good, Outside Member, Special Education and Clinical Sciences

xiii, 89 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Participation in athletics includes an inherent risk of becoming injured that is related to the nature of the games and activities of the players. Current literature reports that approximately seven million high school students participate in sports yearly in the United States and, during the 2005-2006 sport seasons, 1.4 million injuries were reported. Considering this high number of injuries, there is little doubt that definitive research into the determination of factors that might help predict the degree of injury risk associated with sport participation is warranted. Despite common association of variables such as joint laxity, range of motion, strength and balance with injury, these traditional measures have not proven to be reliable predictors of vulnerability. Consequently, attempts have been made to identify practical methods that may better permit identification of individuals who show a high likelihood of injury during athletic competition. This study examined one such system, the Functional Movement Screen (FMS), which utilizes measures of mobility and stability to permit its developers to assert that it can be used to practically and accurately identify vulnerable athletes. Critical data on inter-rater and intra-rater performance were first obtained on a team of athletic trainers to ensure that they could reliably execute the testing methods. Following confirmation of this fact, 112 high school basketball athletes were screened with the FMS and their injuries (non-contact neuromusculoskeletal tissue damage in school-sanctioned basketball) were tracked throughout an entire season. Data analysis to determine if a commonly-used FMS cutoff score of less than 14 out of 21 could identify vulnerable athletes revealed that this value was not significantly related to the likelihood of sustaining an injury. Furthermore, logistic regression revealed that none of the individual predictors (gender, FMS movements, and movement asymmetries) were significant predictors of injury susceptibility. The results indicate that, despite the fact that multiple evaluators and trials can be practically used to evaluate FMS scores in a large group of high school basketball athletes, the test does not appear to be a valid tool in assessing injury risk in this population during an entire season. / Committee in charge: Gary Klug, Chairperson, Human Physiology; Paul van Donkelaar, Member, Human Physiology; Andrew Lovering, Member, Human Physiology; Roland Good, Outside Member, Special Education and Clinical Sciences

Syfte I dagsläget finns det forskning som ger underlag till evidens inom stretching och dess effekter på såväl prestation som skadeprevention. Det finns dock få studier som visar vilka uppfattningar löptränare och löpare har angående stretching. Syftet med studien var därför att beskriva vilka uppfattningar löptränare och elitlöpare har om stretching och dess eventuella effekter på såväl prestation som skadeprevention. Metod Undersökningen inkluderade fyra löptränare (män i åldrarna 30-60 år) och fyra elitlöpare (två kvinnliga respektive två manliga i 20-årsåldern) som valdes ut genom ett bekvämlighetsurval. De deltog i en halvstrukturerad intervju med primära frågor samt tilläggsfrågor enligt ett strukturerat intervjuprotokoll skapat av projektledarna. Varje intervju spelades in, transkriberades och analyserades med hjälp av fenomenografisk analysmetod. Resultat Löptränarnas och elitlöparnas uppfattningar om effekter av stretching var positiva angående såväl rörlighetsförmåga som skadeprevention. Deltagarna hade skilda uppfattningar vad gäller effekter på prestation, två löpare menade att stretching ger positiva effekter medan resterande deltagare uppfattade att stretching inte ger någon effekt. Slutsatser Löptränarna och elitlöparna hade överlag en positiv uppfattning om stretching i relation till skadeprevention vilket går helt emot den aktuella evidensen. Deltagarna uppfattade rörlighetsförmågan som viktig för långdistanslöpare vilket inte är bevisat i vetenskapliga studier. Det förelåg skillnader i uppfattningar om positiva effekter på prestationen vilket också indikerar kunskapsluckor angående stretching kopplat till prestationsförmågan. Det finns en tydlig kunskapsbrist inom området stretching trots att tränarna har en hög utbildningsnivå inom träning. / Purpose As of right now there is research that provides a foundation for evidence regarding stretching and its effects on performance as well as injury prevention. There is however few studies showing how running coaches and runners perceive stretching. The purpose of this study was therefore to describe how running coaches and elite runners perceive stretching and its potential effects on performance as well as injury prevention. Method The survey included four running coaches (men in the ages 30-60 years old) and four elite runners (two women and two men in their twenties) selected through a convenience survey. They participated in a semi-structured interview with primary questions and additional questions according to an organized interview protocol created by the project managers. Each interview was recorded, transcribed and analyzed with phenomenografic analyze method. Results The running coaches and the elite runners perceptions about stretching was positive regarding mobility as well as injury prevention. The participants had different perceptions regarding effects on performance, two runners and one coach suggested that stretching provides positive effects while the remaining participants perceived that stretching did not produce any effect. Conclusion The running coaches and the elite runners had an overall positive perception regarding stretching in relation to injury prevention which is completely opposite to the current evidence. The participants perceived mobility as something important for long-distance running which has not yet been proven in research studies. Positive effects on performance were perceived differently which also indicates a lack of knowledge regarding stretching and performance. There is a clear knowledge gap regarding stretching despite a high level of coaching education.

Syftet med denna studie var att undersöka effekten av 6 veckors styrketräning med så kallad Nordic Hamstring Exercise (NHE) i jämförelse med Razor Hamstring Curl (RHC) med avseende på hamstringsmuskulaturens styrka och rörlighet hos unga fotbollsspelare.   43 fotbollsspelande ungdomar från två olika lag rekryterades till studien varav 40 slutförde den. Deltagarna var av manligt kön och hade en medelålder på 17.2 ± 0.6. De randomiserades till två olika interventionsgrupper, NHE och RHC, där de fick utföra tilldelad övning under träningstid under sex veckor. Mätning av hamstrings rörlighet och isometrisk utvärdering av hamstrings muskelstyrka i 90°-, 45°- och 0°- knävinkel utfördes innan och efter intervention. Parade t-test och Wilcoxon signed rank test användes för att testa förändringen inom grupp och ANCOVA användes för att se skillnaderna mellan grupperna.    NHE-gruppen hade en signifikant ökning av muskelstyrkan i samtliga testvinklar. RHC gruppen hade signifikant ökning i endast två av tre testvinklar. Mätningen i 0° visade ingen signifikant ökning av muskelstyrkan. Rörligheten hade en signifikant ökning i båda interventionsgrupperna. När interventionsgrupperna testades mot varandra så hade NHE gruppen en signifikant högre ökning av muskelstyrkan i 0° mätningen jämfört med RHC gruppen. Ingen signifikant skillnad uppmärksammades i de andra testvinklarna eller i ökningen av rörligheten.   Både NHE- och RHC-träning under 6 veckor resulterade i signifikant ökning av muskelstyrka och rörlighet i hamstringsmuskulaturen hos unga fotbollsspelare. NHE resulterade dock i en signifikant större ökning av muskelstyrkan i ett större rörelseomfång än RHC-övningen. Baserat på resultaten i denna studie är NHE den föredragna metoden att inkludera i framtida träningsprogram.

The purpose of this present study was to assess the feasibility and determine the potential short-term efficacy of implementing a specific 9-week “Yoga for Rowers” (ROWGA) program on male varsity rowers during a competitive training season. Sixteen competitive male varsity rowers (20.6 ± 2.1 years) were recruited to participate, using a single group, pre-test-post-test, quasi-experimental research design. All participants performed two 60 min ROWGA sessions per week for 9 weeks during their fall competitive season. The primary objectives were to test the efficacy of a ROWGA program in a real-world context by evaluating: 1) the feasibility of implementing the program during the training and competitive season as measured by program adherence; 2) its potential effect on strength by evaluating hip muscle strength acting in the sagittal, frontal, and transverse planes as well as on hip muscle strength ratios between the agonist versus antagonist muscle groups; and 3) its potential effect on hip flexion range of motion (ROM). Two pre-test baseline measurements were performed on all participants over 1- week prior to initiating the ROWGA sessions while a single post-test was conducted following the ROWGA intervention. Intraclass correlation coefficients for ROM and strength were used to determine reliability of measurements by taking the two pre-intervention test scores. Outcome measures included hip flexion range of motion, peak isometric hip muscle forces normalized to body weight, including hip flexors, extensors, abductors, adductors, both internal and external rotators as well as peak isometric agonist-antagonist hip muscle strength ratios. Pre and post peak isometric hip strength measurements were calculated for agonist-antagonist muscle groups within each plane by dividing flexors by extensors, adductors by abductors, and internal by external rotators. Feasibility of the ROWGA program was determined from program attendance and adherence rates. The adherence rate was considered high with 89% attending all sessions, after adjusting for compulsory competitions. Significant improvements in peak isometric strength were demonstrated for hip flexors, extensors, abductors, and adductors, and external rotators, while a significant reduction for hip flexion ROM was observed. No significant changes in isometric hip muscle strength agonist-antagonist ratios were demonstrated. The results from this research support the feasibility of the ROWGA program in terms of rower’s acceptance, adherence, and the ability to accommodate the time requirements within their schedule as well as potential strength benefits gained. This research could help provide a platform for future large-scale research related to injury prevention in rowing. / Graduate / 2021-04-06

Background: To perform general warm-up prior to athletics is widely recognized and has adocumented effect on performance. Lower extremity injuries are commonly occurring forsoccer, handball, volleyball, and floorball players. Injury prevention exercises decreases therisk for musculoskeletal injuries, supposing good compliance exists. Whether injurypreventive exercises may increase performance is to this day unclear. Aim: The aim of the study was to compare performance measured in vertical jump height ofathletes after injury preventive exercises and general warm-up. Methods: Experimental study with a cross-sectional design. 17 active soccer, handball,volleyball, and floorball players between 20-32 years were recruited through conveniencesampling. Data was collected occurred by measurement of maximal vertical height done bycountermovement jump (CMJ) on an electronic contact mat. Results: No statistically significant differences regarding vertical jump height wereidentified when comparing injury preventive exercises and general warm-up. Conclusion: The result from the study suggests that male soccer and handball players maybenefit from performing injury prevention exercises instead of general warm-up prior tomaximal vertical jumps due to the decreased risk for injury while the effects of general warmup still emerges. Further research within the subject is necessary to investigate whetherinjury prevention exercises may replace general warm-up prior to more complexperformances such as sports. Further research on others than male handball and soccerplayers should be conducted.

Background: The risk of future injury appears to be influenced by agonist fascicle length (FL), joint range of motion (ROM) and eccentric strength. Biomechanical observations of the torque-angle-relationship further reveal a strong dependence on these factors. In practice, a longer FL improves sprinting performance and lowers injury risk. Classical stretching is a popular and evidenced-based training for enhancing ROM but does not have any effects on FL and injury risk. However, recent studies show that eccentric-only training (ECC) improves both flexibility and strength, and effectively lowers risk of injury. Objectives: To review the evidence on benefits of ECC for flexibility and strength. Methods: COCHRANE, PUBMED, SCOPUS, SPOLIT, and SPONET were searched for laboratory trials that compare ECC to at least one comparison group. Studies were eligible if they examined both strength and flexibility metrics in a healthy sample (<65 years) and met criteria for controlled or randomized clinical trials (CCT, RCT). 18 studies have been included and successfully rated using the PEDro scale. Results: 16 of 18 studies show strong evidence of strength and flexibility enhancements for the lower limb. While improvements between ECC and concentric training (CONC) were similar for eccentric (+19 ± 10% vs. +19 ± 11%) and isometric strength (+16 ± 10% vs. +13 ± 6%), CONC showed larger improvements for concentric strength (+9 ± 6% vs. +16 ± 7%). While for ROM ECC showed improvements (+9 ± 7%), no results could be found for CONC. The overall effectiveness of ECC seems to be higher than of CONC. Conclusion: There is clear evidence that ECC is an effective method for changes in muscle architecture, leading to both flexibility and strength improvements for the lower limb. Due to limited data no shoulder study could be included. Further research is needed for the upper body joints with a focus on functional and structural adaptions.

Bakgrund: Knäkontroll är ett svenskt skadeförebyggande träningsprogram som visat sig ha god effekt för prevention mot främre korsbandsskador vilket är en vanlig knäskada inom fotboll både på herr- och damsidan. Idag finns det studier som utforskat tränares syn och erfarenheter av Knäkontroll och generell skadeförebyggande träning, i nuläget finns det dock en kunskapslucka om vad fotbollsspelare själva har för upplevelser och erfarenheter av att genomföra träningsprogrammet Knäkontroll.  Syfte: Att undersöka fotbollsspelande unga vuxnas upplevelser och erfarenheter av att genomföra SISU:s skadeförebyggande träningsprogram Knäkontroll. Syftet var dessutom att få kännedom om hindrande och underlättande faktorer för genomförande av programmet för att möjliggöra utveckling. Metod: Kvalitativ design i form av en semistrukturerad intervjustudie med fem deltagare från ett bekvämlighetsurval. Databearbetningen genomfördes med kvalitativ innehållsanalys.   Resultat: Fem kategorier presenterades; Hur programmet används av lagen, Vikten av kunskap, Programmets positiva påverkan på kroppen, Spelarnas roll och ansvar och Klubbarnas möjligheter och ansvar. Varje kategori bestod av två till fem subkategorier där några av de mest prominenta var; Timing på när Knäkontroll utförs, Tidsaspekten och Utbildning är essentiellt.  Slutsats: Deltagarnas upplevelser av att utföra Knäkontroll var både positiva och negativa. Deltagarna beskrev även flertalet hindrande och underlättande faktorer för att programmet skulle utföras. I linje med tidigare forskning lyftes det upp att implementering av Knäkontroll i uppvärmningen, kunskap, utbildning och tydliga instruktioner sågs som de viktigaste faktorerna för att underlätta användning av programmet. / Background: Knee control is a Swedish injury prevention training program that has been shown to have good effects on preventing anterior cruciate ligament injuries which is a common Knee injury in both men's and women's football. Today there are studies which have explored football coaches´ views and experiences of Knee control, however there is a knowledge gap on views and experiences of the program from the football players themselves.   Objective: To explore football playing young adults' experiences of utilizing Knee control from SISU to get information about facilitating factors and barriers for implementation of the program for further development. Method: A qualitative method in the form of semi-structured interviews with five participants from a convenience sample. Data processing consisted of qualitative content analysis.  Results: Five categories were presented; How the programme is used by the teams, The importance of knowledge, The programme’s positive impact on the body, The role and responsibilities of the players and The club’s opportunities and responsibilities. Every category consisted of two to five subcategories where some of the most prominent were; Timing on when Knee Control is performed, The time aspect and Education is essential. Conclusion: The participants' experiences of performing Knee control was both positive and negative. The participants also highlighted the most hindering and facilitating factors for the program to be carried out. In line with previous research, it was highlighted that implementation of Knee control in the warm-up, knowledge, education and instructions was seen as the most important factors in facilitating use of the program.

No description available.

Pedal misapplication (PM) is an error in which a driver unintentionally presses the wrong pedal. When drivers mistake the accelerator pedal for the brake pedal, the vehicle experiences a sudden unintended acceleration, and the consequences can be severe. A brief history of PM is covered, and several novel studies of PM are described. The goals of these studies were as follows: 1. Identify and analyze multiple samples of PM crashes from a variety of data sources using both established and novel methods to gain new insight into the characteristics and frequency of PM crashes. 2. Use the confirmed, real-world PM crash data to develop a custom vehicle dynamics simulation and evaluate the overall potential safety benefit of a theoretical PM advanced driver assistance system. Using an established keyword search identification method and two unique crash datasets, a PM crash frequency of approximately 0.2% of all crashes was found. These PM crashes were typically rear-end or road departure crashes in moderate- to low-speed commercial or residential areas. Female drivers and elderly drivers were more often involved in these PM crashes, which generally featured slightly lower injury severities and often involved inattention or fatigue. Anecdotally, PM crash narratives contained repeated evidence of unexpected events, driver inexperience, distraction, shoe-malfunction, extreme stress, and medical conditions/emergencies. A novel PM crash identification algorithm was developed to detect PMs from time-series pre-crash data. This algorithm was applied to a sample of crashes with event data recorder data available, and a frequency of 4.3% of eligible crashes were found to have exhibited PM behavior, suggesting that PM crashes may be more prevalent than previously thought. While the data from these crashes suggested that a PM occurred, this dataset lacked sufficient data regarding driver intention, which is necessary to confirm each crash as PMs. The characteristics of these PM-like crashes were analyzed and found to be largely similar to those of previous samples, with notable exceptions for higher proportions of male drivers, higher travel speeds, and higher maximum injury severities. More robust data from a naturalistic driving study (NDS) was acquired, and the novel algorithm was applied to all of the sample’s eligible crashes. Because the NDS data contained more data elements such as driver-facing video, crashes that exhibited PM behavior were individually inspected to confirm PM. This produced a PM crash frequency of 1.1%. The characteristics of these confirmed PM crashes were investigated, but a small sample size limits the generalizability of the results. Lastly, crash data from confirmed, real-world PM crashes was used to inform a custom vehicle dynamics model into which a theoretical PM advanced driver assistance system was simulated. The effect of the accelerator suppression system on crash avoidance and mitigation was evaluated to assess its potential safety benefit, which was found to be highly dependent on system threshold values and largely underwhelming in the absence of supplemental braking. The results indicated that a system that detected PM, suppressed acceleration, and applied braking could provide a substantially higher safety benefit. / M.S. / Pedal misapplication (PM) occurs when a driver presses the wrong pedal. When drivers mistake the accelerator pedal for the brake pedal, the vehicle experiences a sudden unintended acceleration, and the consequences can be severe. A history of the controversial subject of PM is covered, and several novel studies of PM are described. In these studies, PM crashes are identified among documented real-world crashes. This is done in three phases: (1) using narratives written by law-enforcement officers or crash investigators, (2) using event data recorders, or “black boxes,” that store vehicle data prior to crashes, and (3) using naturalistic driving study data, including video recordings of subjects during daily driving. These data are analyzed to develop the understanding of how often PM crashes occur and what factors are common among them. It is discovered that the frequency of PM crashes may be an order of magnitude greater than previously estimated. In the final study, real-world PM crash data is used to virtually reconstruct PM crashes and apply an advanced driver assistance system designed to detect PM, suppress the accelerator input, and reduce the severity of the crash or prevent it altogether. By simulating a wide range of system variations, we develop a sense of the feasibility of such a system’s implementation and overall safety benefit.