An Explorative Investigation of the Warm-up Practices of Professional and Amateur Rugby League Players

This study aimed to assess warm-up practices within professional and amateur Rugby League players, specifically to determine players’ perceptions why particular methods were used and discover whether any differences existed in warm-up practices and perceptions between the two separate standards. The study used a 10 question online questionnaire to investigate 30 professional and 53 amateur players warm-up protocols and their perceptions behind their practices. To provide a richer understanding regarding the practices and perceptions surrounding warm-up protocols, the questionnaire was followed by two focus groups (professionals and amateurs), which included four participants in each. Following analysis of the questionnaire responses, it was discovered that professional players warm-up protocols were significantly longer in duration than amateur players (P = 0.009). However, for all other variables assessed including; specific warm-up protocols, static stretch duration, and perceptions and beliefs concerning warm-up protocols, there were no significant differences between professionals and amateurs. Overall findings demonstrated the widespread use of static stretching within warm-up for both professionals and amateurs; 71 of 83 players (86%) reported usage. It was also highlighted that injury prevention was the most commonly perceived benefit from performing a warm-up across both standards [(Professional; 15 of 30, 50%) (Amateur; 27 of 53, 51%)]. Findings from the focus group generally supported questionnaire responses, and it was identified that the warm-up practices and protocols of Rugby League players were influenced by others such as coaches and strength and conditioning coaches which emphasises the importance of the role such practitioners

An 8 week neuromuscular training programme reduces the risk of ACL injury and increases athletic performance variables in female court sport athletes

Court sport athletes repetitively perform movements which require physical attributes such as agility, acceleration, muscular power, muscular strength and balance. Unfortunately, some of the movements performed by court sport athletes such as changing direction quickly, decelerating and landing from a jump put athletes at an increased risk of injury their anterior cruciate ligament. Females in particular are at an increased risk of injuring this ligament in comparison to their male counterparts. The purpose of this study was to investigate if a neuromuscular training protocol increased athletic performance variables and reduced the risk of ACL injuries in female court sport athletes. Twenty female court sport athletes took part in this study (stature: 169 ± 7 cm, mass: 61.3 ± 8.3 kg, age: 22.3 ± 2.0 years, competitive playing experience: 5.4 ± 1.6 years). Participants were split evenly through random allocation, comprising of ten in the control group and ten in the intervention group. Both the control and intervention groups pre-tests involved a 20 m sprint, counter-movement jump (CMJ), Illinois agility test and the Qualitative Analysis of a Single Leg Squat (QASLS), which is an assessment used to profile a participant’s risk of an ACL injury. After the pre-tests the intervention group engaged in a modified version of the Fifa 11+ neuromuscular training programme twice a week over an eight week period. During this eight week period both groups were instructed to continue with their habitual training regimes as delivered to them by their sport coaches. After eight weeks both the control and intervention group participants were recalled to repeat the pre-test protocols. A 2 (Control vs. Intervention) x 2 (Pre vs. Post – within subjects) mixed ANOVA demonstrated significant improvements for the intervention group’s CMJ (9.7% improvement) and QASLS (117% improvement on left leg and 65% on the right) in comparison to the control group following the training intervention. No significant differences between the two groups were found for the Illinois agility test and 20 m sprint. However, there was a within-group improvement in 20 m sprint for the intervention group post training (2.2% decrease). The results demonstrate a modified Fifa 11+ protocol can be considered an effective neuromuscular training programme for reducing the risk of ACL injuries and improving athletic performance variables in female court sport athletes

Investigations of ash layer characteristics and ash distribution in a diesel particulate filter using novel lubricant additive tracers

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 59, 62).Diesel particulate filters (DPF) are currently widely used in various applications as a means of collecting particulate matter in order to meet increasingly stringent particle emissions regulations. Over time, the DPF slowly accumulates incombustible material or ash, mostly from the metallic additives present in the engine lubricant. This build up of accumulated ash leads to an increase in flow restriction and therefore an increase in pressure drop along the DPF. The increased pressure drop negatively impacts engine performance and fuel economy, and it also requires eventual filter removal for ash cleaning. While the major effects of ash accumulation on DPF performance are known, the fundamental underlying mechanisms are not. This work is focused on understanding key mechanisms, such as the soot deposition and the ash formation, accumulation, and distribution processes, which play a major role in determining the magnitude of the ash effect on DPF pressure drop. More specifically, it explores the location of ash deposit accumulation inside the DPF channels, whether in a layer along the filter walls or packed in a plug at the rear of the channels, which is one of the key factors controlling DPF pressure drop. A specialized experiment was set up by running three different lubricants, each with its own unique additive tracer, sequentially through a diesel burner system. Scanning electron microscopy (SEM) was used to analyze the evolution of the ash deposits in the DPF samples in order to explain the specific mechanisms and processes controlling ash properties and their effect on DPF pressure drop. The experimental results were compared and correlated with previous DPF test data and theoretical models, providing additional insight to optimize diesel particulate filter performance. The results are useful in optimizing the design of the engine, aftertreatment, and lubricant systems for future diesel engines, balancing the requirements of additives for adequate engine protection with the requirements for robust after treatment systems.by Ryan Morrow.S.B

An explorative investigation into the warm-up practices of both professional and amateur rugby league players

PURPOSE: Rugby League (RL) players require high levels of speed, strength, power, agility and psychological readiness. Optimum preparation for performance via warm-up (WU) routines has been an area of research speculation in recent years. This study aimed to survey the WU protocols of professional and amateur RL players, to determine player’s perceptions of their featured WU procedures and to establish any significant differences in WU practices and perceptions between the two populations. METHODS: An online questionnaire was used to investigate 30 professional and 53 amateur players’ WU protocols and their perceptions behind their practices, providing both statistical and descriptive analysis. For a more in depth understanding into the practices and perceptions of the featured protocols, the questionnaire was followed up by two focus groups which included four participants in each (one professional group and one amateur). Raw data was produced from the focus groups which was then placed within higher-order themes and general dimensions. RESULTS: The questionnaire revealed a significant between-group difference for the duration of the WU’s between the two separate standards (P = 0.009). Professionals’ WU protocols were considerably longer in duration compared to the amateurs’ protocols; 67% of professional players performed WU routines for 15+ min whereas only 42% of amateur players claimed to WU for 15+ min. However, no between-group differences existed for protocols, perception variables, static stretching (SS) duration and similarity of the WU protocol (P > 0.05). The questionnaire also revealed the prevalence of SS; 83% of amateur participants and 90% of professional players claimed to perform SS during their WU. The focus group revealed that RL players’ protocols and perceptions of their regime are due to the influences of others such as coaches, strength and conditioning practitioners and physiotherapists and emphasises the importance the role such professionals play. CONCLUSIONS: The results showed that professional participants WU for a longer period in comparison to amateurs. The high prevalence of SS within RL WU protocols at both a professional and amateur standard was clearly apparent, contradicting the vast amount of literature that would advocate the removal of SS in sports requiring explosive power due to the associated links with decrements in performance. Most professional and amateur RL participants were discovered to perform SS for a duration that has been proven to impair desired physiological attributes. Furthermore, the study revealed the dynamic element of a WU is being consistently placed before SS, by both the professional and amateur domain, which has been previously linked to decreases in body temperature and associated mechanisms related mechanisms. Players associated that there WU practice was heavily influenced by RL coaches and associated practitioners. PRACTICAL APPLICTIONS: It is recommended that coaches, strength and conditioning practitioners and other key influential figures are educated on optimal evidence based WU procedures prior to prescription. Important aspects for consideration and education include WU duration, intensity, protocol order and SS elongation, volume and duration. Whilst it is important to link the research in WU to performance, practitioners should be mindful of changing regimes abruptly and the idiosyncratic nature of how athletes prefer to prepare physically and mentally

Facing Real-World Challenges of Immunogenicity in Pediatric Inflammatory Bowel Disease

The advent of biological therapies drastically altered the landscape of inflammatory bowel disease (IBD) treatment, making long-term steroid-free remission possible for thousands of patients living with this chronic inflammatory condition that compromises the integrity of the gastrointestinal mucosa. Unfortunately, up to 65% of patients with IBD develop anti-drug antibodies to biologics (1). This is especially problematic for pediatrics, where treatment options are substantially more limited than for adult patients. Currently, only two biologics have approval from the United States (U.S.) Food and Drug Administration (FDA) for pediatric indications in IBD, anti-TNF-α agents infliximab (IFX), and adalimumab (ADM). The fear of losing these two agents to immunogenicity is very real for the providers and the families of the ~70,000 children affected by IBD in the U.S. (2)

Comparing estimates of child mortality reduction modelled in LiST with pregnancy history survey data for a community-based NGO project in Mozambique

<p>Abstract</p> <p>Background</p> <p>There is a growing body of evidence that integrated packages of community-based interventions, a form of programming often implemented by NGOs, can have substantial child mortality impact. More countries may be able to meet Millennium Development Goal (MDG) 4 targets by leveraging such programming. Analysis of the mortality effect of this type of programming is hampered by the cost and complexity of direct mortality measurement. The Lives Saved Tool (LiST) produces an estimate of mortality reduction by modelling the mortality effect of changes in population coverage of individual child health interventions. However, few studies to date have compared the LiST estimates of mortality reduction with those produced by direct measurement.</p> <p>Methods</p> <p>Using results of a recent review of evidence for community-based child health programming, a search was conducted for NGO child health projects implementing community-based interventions that had independently verified child mortality reduction estimates, as well as population coverage data for modelling in LiST. One child survival project fit inclusion criteria. Subsequent searches of the USAID Development Experience Clearinghouse and Child Survival Grants databases and interviews of staff from NGOs identified no additional projects. Eight coverage indicators, covering all the project’s technical interventions were modelled in LiST, along with indicator values for most other non-project interventions in LiST, mainly from DHS data from 1997 and 2003.</p> <p>Results</p> <p>The project studied was implemented by World Relief from 1999 to 2003 in Gaza Province, Mozambique. An independent evaluation collecting pregnancy history data estimated that under-five mortality declined 37% and infant mortality 48%. Using project-collected coverage data, LiST produced estimates of 39% and 34% decline, respectively.</p> <p>Conclusions</p> <p>LiST gives reasonably accurate estimates of infant and child mortality decline in an area where a package of community-based interventions was implemented. This and other validation exercises support use of LiST as an aid for program planning to tailor packages of community-based interventions to the epidemiological context and for project evaluation. Such targeted planning and assessments will be useful to accelerate progress in reaching MDG4 targets.</p