Thesis (Ed.M.)--Boston University

student number: 9305872K M.Sc (Med) Dissertation - School of Physiology / Most performance assessments on athletes involve an excessive amount of testing procedures. The efficacy of these tests is not always apparent, and their application is not always practical. Elite male middle-distance runners (n=20) were used to assess the physiological determinants of 800 meter running performance. We used testing methods recommended by the South African Sports Commission, which included body composition, joint flexibility, muscular strength, -power and -endurance, as well as a Wingate test (anaerobic capacity) and an isokinetic evaluation. An assessment of maximal running speed and acceleration at distances up to 300 meters was conducted on a standard tartan track. In addition, maximal oxygen consumption (VO2max), running economy, onset of blood lactate accumulation (OBLA) and the maximal accumulated oxygen deficit (MAOD) were determined. Measured values were correlated with competitive performance times using the Pearson product-moment correlation technique, with the Bonferroni correction for multiple comparisons. Wingate mean- and minimum power, as well as running times at 40, 60, 70, 80, 90, 150 and 300 meters were found to be significantly correlated to performance (r2>0.4; p<0.01). A multiple correlation comparison was used to determine a significant difference between correlations with performance time for the different variables. A stepwise multiple regression determined that 300 meter time-trial time was the strongest predictor of performance, accounting for 79% of the variability in performance, which was a better predictor of performance than a prediction model. The following formula was derived to estimate 800 meter performance from 300 meter time-trial time: 800m time = 37.1062 + 2.17(300m time) [time in seconds] The tests most able to predict 800 meter running performance were sport-specific track tests of high-speed running ability and tests of anaerobic capacity (especially the Wingate cycle ergometer test).

We examine the problem of staffing refreshment stations at a long distance road race. A race is modeled as a mixed queueing network in which the required number of servers at each service station has to be estimated. Two models to represent the progress of runners along a long distance road race course are developed. One model is a single-class model that allows a road race manager to staff service stations assuming the runners are identical to those in some historical dataset. Another model is a multi-class simulation model that allows a road race manager to simulate a race of any number of runners, classified based on their running pace into different runner classes. Both the single-class model and the multi-class model include estimates for the rates at which the runners arrive at specified locations along the course. The arrival rates, combined with assumed service rates, allow us to base staffing decisions on the Erlang loss formula or a lesser known staffing rule that gives a lower bound for the required number of servers. We develop a staffing strategy that we call the Peak Arrival Staffing Bound (PASB), which is based on this staffing bound. The PASB and the Erlang loss formula are implemented in the single-class model and the multi-class simulation model. By way of numerical experiments, we find that the PASB is numerically stable and can be used to get staffing results regardless of the traffic intensity. This finding is in contrast to the Erlang loss formula, which is known to become numerically unstable and overflows when the traffic intensity exceeds 171. We compare numerical results of the PASB and the Erlang loss formula with a blocking probability level of 5% and find that when iii the traffic intensity is high, staffing results based on the PASB are more conservative than staffing results based on the Erlang loss formula. As the traffic intensity gets lower, we find that staffing results based on the PASB are similar to staffing results based on the Erlang loss formula. These findings suggest that the PASB can be a valuable tool to aid race directors in making staffing decisions for races of all traffic intensities

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Sammanfattning   Syfte och frågeställningar Syftet med denna studie var att sammanställa kvalitet på och resultat av studier som undersökt om långdistanslöpning ger artros i höft-, knä- eller fotleder. Finns det vetenskaplig evidens för att långdistanslöpning ger artros i höft-, knä- eller fotleder? Vilka styrkor och svagheter har de studier som försökt utröna om samband finns mellan långdistanslöpning och artros i höft-, knä- eller fotleder?   Metod Sökning av litteratur utfördes i PubMed, CINAHL, Cochrane Library och PEDro. Detta resulterade i att tio artiklar inkluderades för närmare granskning och sammanställning. Utifrån artiklarnas sammantagna bevisvärde poängsattes och graderades artiklarna efter evidensnivå enligt Statens Beredning för medicinsk Utvärderings (SBU) granskningsmallar för kohortstudier med kontrollgrupper.   Resultat Endast en av tio studier visar ett positivt samband mellan långdistanslöpning och artros i höft-, knä- eller fotleder, i detta fall höftledsartros. Studierna har ingen tydlig och gemensam definition över vad långdistanslöpning är. De granskade studierna använder sig av olika mätmetoder för att bedöma leddegenerationen, både av självrapportering och av olika diagnostiska kriterier för artros. Alla studier har inslag av selektionsbias.   Slutsats En indikation på att det inte finns ett vetenskapligt stöd för att långdistanslöpning ger höft-, knä- eller fotledsartros hos människor. Studierna har brister i hantering av confounders och selektionsbias och bedöms vara av låg eller medelhög kvalitet. / Abstract   Aim The purpose of this study was to compile the quality and results of studies that examined if long-distance running gives osteoarthritis of the hip, knee or ankle joints. Is there scientific evidence that long-distance running gives osteoarthritis of the hip, knee or ankle? What strengths and weaknesses of the studies attempted to determine if the link between long-distance running and osteoarthritis of the hip, knee or ankle joints.   Method Search of the literature was performed in PubMed, CINAHL, Cochrane Library, and PEDro. This resulted in ten articles that were included for further review and compilation. Based on the articles combined probative value was scored and graded articles for level of evidence according to the National Council on Technology Evaluation (SBU) examination templates for cohort studies with control groups.   Results Only one of the ten studies showed a positive association between long distance running and osteoarthritis of the hip, knee or ankle joints, in this case hip joint. The studies have not a clear and common definition of what long-distance running is. The studies reviewed use different metrics to assess joint degeneration, both by self-report and of different diagnostic criteria for osteoarthritis. All studies have an element of selection bias.   Conclusion An indication that there is no scientific evidence that long-distance running gives hip, knee or ankle osteoarthritis in humans. The studies were inadequate handling of confounders and selection bias and judged to be of low or medium quality.

Research on athletes has shown that mental skills are an important component of being a successful athlete. The importance of these mental skills is seen in the number of athletes who have formally started training using mental skills training programmes (MST) according to the literature. The study of mental skills in South Africa lags behind other countries like USA, UK and Sweden. This particular study explored the use of mental skills by road running athletes. The study was conducted with six competitive marathon athletes. Semi-structured interviews were conducted as part of an elaborate qualitative methodology design. The data collected from these semi-structured interviews was analysed using thematic analysis. The results show that road running athletes use mental skills that include; mental rehearsal, planning, goal setting and self-talk. The athletes in this research showed the importance of mental skills and it is recommended that formal training in these mental skills will be highly beneficial not only to road running athletes but for all South African sports people in general

Thesis (M.Thec.:Chiropractic)-Dept. of Chiropractic, Durban Institute of Technology, 2005 xiii, 110 leaves ; ill. ; 30 cm / According to Wood (1998), patellofemoral pain syndrome (PFPS) refers to a syndrome that comprises of the following signs and symptoms: anterior knee pain, inflammation, imbalance, instability, or any combination thereof. Prevailing literature suggests that the presence of myofascial trigger points (MFTP’s) in quadriceps femoris (QF) muscle could result in a combination of the following signs and symptoms: - Retro- or peripatella pain, - Weakness of the quadriceps muscle (Chaitow and DeLany, 2002) - Loss of full lengthening (Travell and Simons, 1983:248-250) The aetiology of PFPS is poorly understood (Kannus et al. 1999). The current trend in literature suggests an extensor mechanism dysfunction as the most probable aetiology (Galantly et al., 1994; Juhn, 1999). There appears to be a clinical overlap between the two syndromes, in terms of an extensor mechanism dysfunction and of signs and symptoms. The aim of this investigation was to evaluate the role of active myofascial trigger points in the vastus lateralis (VL) muscle as perpetuating, causative or concomitant factors in the alteration of VL/VM Total Work (TW) in PFPS in distance runners.

Thesis (M.Tech,: Chiropractic)- Dept. of Chiropractic, Durban Institute of Technology, 2005 xiii, 62, 19 leaves :|bill. ;|c30 cm / To document the relationship between total work and myofascial trigger points in the vastus lateralis and vastus medialis portion of the quadriceps femoris muscle, whilst providing baseline graphs of these muscles with the use of a Cybex 700 Isokinetic Dynanometer in long distance runners both with and without patellofemoral pain syndrome. Methods: A quantitative, non-intervention clinical exploratory study. Fifty participants were divided into two groups, Group A (40 symptomatics) and Group B (10 asymptomatics). Both groups were screened for vastus lateralis and vastus medialis trigger points. Subjective data was obtained from Group A only, using the Numerical Pain Rating Scale and the Patient Specific Functional Scale. Objective data was obtained from both groups using the algometer, Myofascial Diagnostic Scale, and the Cybex 700 Isokinetic Dynanometer. For descriptive analysis frequency tabulations, box and whisker plots were used to display distributions graphically. Comparisons of categorical and quantitative variables between independent groups were run using chi square and Mann-Whitney testing consecutively. Finally Spearman’s correlation, multivariate generalized linear modelling and repeated measures ANOVA were also used. All statistical analysis was completed at the 95% (p<0.05) level of confidence.

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / According to Wood (1998), patellofemoral pain syndrome (PFPS) refers to a syndrome that comprises of the following signs and symptoms: anterior knee pain, inflammation, imbalance, instability, or any combination thereof. Prevailing literature suggests that the presence of myofascial trigger points (MFTP’s) in quadriceps femoris (QF) muscle could result in a combination of the following signs and symptoms: - Retro- or peripatella pain, - Weakness of the quadriceps muscle (Chaitow and DeLany, 2002) - Loss of full lengthening (Travell and Simons, 1983:248-250) The aetiology of PFPS is poorly understood (Kannus et al. 1999). The current trend in literature suggests an extensor mechanism dysfunction as the most probable aetiology (Galantly et al., 1994; Juhn, 1999). There appears to be a clinical overlap between the two syndromes, in terms of an extensor mechanism dysfunction and of signs and symptoms. The aim of this investigation was to evaluate the role of active myofascial trigger points in the vastus lateralis (VL) muscle as perpetuating, causative or concomitant factors in the alteration of VL/VM Total Work (TW) in PFPS in distance runners.

Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, 2005. / To document the relationship between total work and myofascial trigger points in the vastus lateralis and vastus medialis portion of the quadriceps femoris muscle, whilst providing baseline graphs of these muscles with the use of a Cybex 700 Isokinetic Dynanometer in long distance runners both with and without patellofemoral pain syndrome. Methods: A quantitative, non-intervention clinical exploratory study. Fifty participants were divided into two groups, Group A (40 symptomatics) and Group B (10 asymptomatics). Both groups were screened for vastus lateralis and vastus medialis trigger points. Subjective data was obtained from Group A only, using the Numerical Pain Rating Scale and the Patient Specific Functional Scale. Objective data was obtained from both groups using the algometer, Myofascial Diagnostic Scale, and the Cybex 700 Isokinetic Dynanometer. For descriptive analysis frequency tabulations, box and whisker plots were used to display distributions graphically. Comparisons of categorical and quantitative variables between independent groups were run using chi square and Mann-Whitney testing consecutively. Finally Spearman’s correlation, multivariate generalized linear modelling and repeated measures ANOVA were also used. All statistical analysis was completed at the 95% (p<0.05) level of confidence. / M