Knee flexor strength and bicep femoris electromyographical activity is lower in previously strained hamstrings

The aim of this study was to determine if athletes with a history of hamstring strain injury display lower levels of surface EMG (sEMG) activity and median power frequency in the previously injured hamstring muscle during maximal voluntary contractions. Recreational athletes were recruited, 13 with a history of unilateral hamstring strain injury and 15 without prior injury. All athletes undertook isokinetic dynamometry testing of the knee flexors and sEMG assessment of the biceps femoris long head (BF) and medial hamstrings (MH) during concentric and eccentric contractions at ± 180 and ± 600.s-1. The knee flexors on the previously injured limb were weaker at all contraction speeds compared to the uninjured limb (+1800.s-1 p = 0.0036; +600.s-1 p = 0.0013; -600.s-1 p = 0.0007; -1800.s-1 p = 0.0007) whilst sEMG activity was only lower in the BF during eccentric contractions (-600.s-1 p = 0.0025; -1800.s-1 p = 0.0003). There were no between limb differences in MH sEMG activity or median power frequency from either BF or MH in the injured group. The uninjured group showed no between limb differences in any of the tested variables. Secondary analysis comparing the between limb difference in the injured and the uninjured groups, confirmed that previously injured hamstrings were mostly weaker (+1800.s-1 p = 0.2208; +600.s-1 p = 0.0379; -600.s-1 p = 0.0312; -1800.s-1 p = 0.0110) and that deficits in sEMG were confined to the BF during eccentric contractions (-600.s-1 p = 0.0542; -1800.s-1 p = 0.0473) Previously injured hamstrings were weaker and BF sEMG activity was lower than the contralateral uninjured hamstring. This has implications for hamstring strain injury prevention and rehabilitation which should consider altered neural function following hamstring strain injury.

Rate of torque and electromyographic development during anticipated eccentric contraction is lower in previously strained hamstrings

Background: Hamstring strain injuries are prevalent in sport and re-injury rates have been high for many years. Whilst much focus has centred on the impact of previous hamstring strain injury on maximal eccentric strength, high rates of torque development is also of interest, given the important role of the hamstrings during the terminal swing phase of running. The impact of prior strain injury on myoelectrical activity of the hamstrings during tasks requiring high rates of torque development has received little attention. Purpose: To determine if recreational athletes with a history of unilateral hamstring strain injury, who have returned to training and competition, will exhibit lower levels of myoelectrical activity during eccentric contraction, rate of torque development and impulse 30, 50 and 100ms after the onset of myoelectrical activity or torque development in the previously injured limb compared to the uninjured limb. Study design: Case-control study Methods: Twenty-six recreational athletes were recruited. Of these, 13 athletes had a history of unilateral hamstring strain injury (all confined to biceps femoris long head) and 13 had no history of hamstring strain injury. Following familiarisation, all athletes undertook isokinetic dynamometry testing and surface electromyography assessment of the biceps femoris long head and medial hamstrings during eccentric contractions at -60 and -1800.s-1. Results: In the injured limb of the injured group, compared to the contralateral uninjured limb rate of torque development and impulse was lower during -600.s-1 eccentric contractions at 50 (RTD, injured limb = 312.27 ± 191.78Nm.s-1 vs. uninjured limb = 518.54 ± 172.81Nm.s-1, p=0.008; IMP, injured limb = 0.73 ± 0.30 Nm.s vs. uninjured limb = 0.97 ± 0.23 Nm.s, p=0.005) and 100ms (RTD, injured limb = 280.03 ± 131.42Nm.s-1 vs. uninjured limb = 460.54.54 ± 152.94Nm.s-1,p=0.001; IMP, injured limb = 2.15 ± 0.89 Nm.s vs. uninjured limb = 3.07 ± 0.63 Nm.s, p<0.001) after the onset of contraction. Biceps femoris long head muscle activation was lower at 100ms at both contraction speeds (-600.s-1, normalised iEMG activity (x1000), injured limb = 26.25 ± 10.11 vs. uninjured limb 33.57 ± 8.29, p=0.009; -1800.s-1, normalised iEMG activity (x1000), injured limb = 31.16 ± 10.01 vs. uninjured limb 39.64 ± 8.36, p=0.009). Medial hamstring activation did not differ between limbs in the injured group. Comparisons in the uninjured group showed no significant between limbs difference for any variables. Conclusion: Previously injured hamstrings displayed lower rate of torque development and impulse during slow maximal eccentric contraction compared to the contralateral uninjured limb. Lower myoelectrical activity was confined to the biceps femoris long head. Regardless of whether these deficits are the cause of or the result of injury, these findings could have important implications for hamstring strain injury and re-injury. Particularly, given the importance of high levels of muscle activity to bring about specific muscular adaptations, lower levels of myoelectrical activity may limit the adaptive response to rehabilitation interventions and suggest greater attention be given to neural function of the knee flexors following hamstring strain injury.

Knee flexor strength and biceps femoris activation deficits following hamstring strain injury

Background: Hamstring strain injuries (HSI) are prevalent in sport and re-injury rates have been high for many years. Maladaptation following HSI are implicated in injury recurrence however nervous system function following HSI has received little attention. Aim: To determine if recreational athletes with a history of unilateral HSI, who have returned to training and competition, will exhibit lower levels of voluntary activation (VA) and median power frequency (MPF) in the previously injured limb compared to the uninjured limb at long muscle lengths. Methods: Twenty-eight recreational athletes were recruited. Of these, 13 athletes had a history of unilateral HSI and 15 had no history of HSI. Following familiarisation, all athletes undertook isokinetic dynamometry testing and surface electromyography assessment of the biceps femoris long head and medial hamstrings during concentric and eccentric contractions at ± 180 and ± 60deg/s. Results: The previously injured limb was weaker at all contraction speeds compared to the uninjured limb (+180deg/s mean difference(MD) = 9.3Nm, p = 0.0036; +60deg/s MD = 14.0Nm, p = 0.0013; -60deg/s MD = 18.3Nm, p = 0.0007; -180deg/s MD = 20.5Nm, p = 0.0007) whilst VA was only lower in the biceps femoris long head during eccentric contractions (-60deg/s MD = 0.13, p = 0.0025; -180deg/s MD = 0.13, p = 0.0003). There were no between limb differences in medial hamstring VA or MPF from either biceps femoris long head or medial hamstrings in the injured group. The uninjured group showed no between limb differences with any of the tested variables. Conclusion: Previously injured hamstrings were weaker than the contralateral uninjured hamstring at all tested speeds and contraction modes. During eccentric contractions biceps femoris long head VA was lower in the previously injured limb suggesting neural control of biceps femoris long head may be altered following HSI. Current rehabilitation practices have been unsuccessful in restoring strength and VA following HSI. Restoration of these markers should be considered when determining the success of rehabilitation from HSI. Further investigations are required to elucidate the full impact of lower levels of biceps femoris long head VA following HSI on rehabilitation outcomes and re-injury risk.

Impact of previous hamstring strain injury on rate of torque and EMG development during eccentric contraction.

Background: Hamstring strain injuries (HSIs) are prevalent in sport and re-injury rates have been high for many years. Whilst much focus has centred on the impact of previous hamstring strain injury on maximal eccentric strength, high rates of torque development is also of interest, given the important role of the hamstrings during the terminal swing phase of gait. The impact of prior strain injury on neuromuscular function of the hamstrings during tasks requiring high rates of torque development has received little attention. The purpose of this study is to determine if recreational athletes with a history of unilateral hamstring strain injury, who have returned to training and competition, will exhibit lower levels of eccentric muscle activation, rate of torque development and impulse 30, 50 and 100ms after the onset of electromyographical or torque development in the previously injured limb compared to the uninjured limb. Methods: Twenty-six recreational athletes were recruited. Of these, 13 athletes had a history of unilateral hamstring strain injury (all confined to biceps femoris long head) and 13 had no history of hamstring strain injury. Following familiarisation, all athletes undertook isokinetic dynamometry testing and surface electromyography assessment of the biceps femoris long head and medial hamstrings during eccentric contractions at -60 and -1800.s-1. Results: In the injured limb of the injured group, compared to the contralateral uninjured limb rate of torque development and impulse was lower during -600.s-1 eccentric contractions at 50 (RTD, p=0.008; IMP, p=0.005) and 100ms (RTD, p=0.001; IMP p<0.001) after the onset of contraction. There was also a non-significant trend for rate of torque development during -1800.s-1 to be lower 100ms after onset of contraction (p=0.064). Biceps femoris long head muscle activation was lower at 100ms at both contraction speeds (-600.s-1, p=0.009; -1800.s-1, p=0.009). Medial hamstring activation did not differ between limbs in the injured group. Comparisons in the uninjured group showed no significant between limbs difference for any variables. Conclusion: Previously injured hamstrings displayed lower rate of torque development and impulse during eccentric contraction. Lower muscle activation was confined to the biceps femoris long head. Regardless of whether these deficits are the cause of or the result of injury, these findings have important implications for hamstring strain injury and re-injury and suggest greater attention be given to neural function of the knee flexors.

Physical activity in three regional communities in Queensland

Objective. To describe physical activity participation in three Queensland regional communities. Design. Cross-sectional mail survey of randomly selected residents, stratified by age and sex. Setting. Esk, Mareeba and Mount Isa. Participants. 1219 (58% female) adults, with a mean age 46.7 (SD 14.7) years. Main outcome measures. Proportion of people inactive, meeting Australian activity guidelines (a minimum of 150 minutes/week and 5 sessions/week), and walking a dog daily; time spent walking and cycling for transport; location and type of recreational physical activities. Results. Overall, 18% of respondents were inactive, with the highest proportions among women (22.3%) and older adults in Mount Isa (24.3%). The proportion meeting activity guidelines was 47% with the lowest proportions among women in Mount Isa (40.4%). Although 63% reported owning a dog, only 22% reported walking a dog daily. Few people reported walking or cycling for transport. The most common types of activities were walking, home-based exercise, running/jogging, and swimming, and the most common location was at or near home. Conclusions. Physical activity levels were lower in these regional communities than the state average. The findings indicate a need for physical activity policy and intervention strategies targeting regional and rural areas. This could focus on women and older adults, dog walking, and physical activity opportunities in or near the home.

Quality of life in chronic fatigue syndrome

Whilst the debilitating fatigue experienced in patients suffering from Chronic Fatigue Syndrome (CFS) results in a subjective marked impairment in functioning, little research has investigated the impact of this disorder on quality of life. Forty-seven subjects with a confirmed diagnosis of CFS and 30 healthy controls were compared using the Sickness Impact Profile (SIP). A subgroup of subjects were interviewed regarding the impact CFS has had on their social and family relationships, work and recreational activities. Results from both the SIP and the interview revealed that CFS subjects had significantly impaired quality of life, especially in areas of social functioning. These findings highlight the importance of addressing the social isolation and loss of role functioning experienced by CFS sufferers.

Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres : 13th Volume

"Seventeen peer-reviewed papers cover the latest research on the ignition and combustion of metals and non-metals, oxygen compatibility of components and systems, analysis of ignition and combustion, failure analysis and safety. It includes aerospace, military, scuba diving, and industrial oxygen applications. Topics cover: • Development of safe oxygen systems • Ignition mechanisms within oxygen systems and how to avoid them • Specific hazards that exist with the oxygen mixture breathed by divers in the scuba industry • Issues related to oxygen system level safety • Issues related to oxygen safety in breathing systems • Detailed investigations and discussions related to the burn curves that have been generated for metals that are burning in a standard test fixture This new publication is a valuable resource for professionals in the air separation industries, oxygen manufacturers, manufacturers of materials intended for oxygen service, and users of oxygen and oxygen-enriched atmospheres, including aerospace, medical, industrial gases, chemical processing, steel and metals refining, as well as to military, commercial or recreational diving."--- publisher website

Social media and Web 2.0 : teacher-librarians, risk and inequity

This paper reports research into teacher-­‐librarians’ perceptions of using social media and Web 2.0 in teaching and learning. A pilot study was conducted with teacher-­‐librarians in five government schools and five private schools in southeast Queensland. The findings revealed that there was a strong digital divide between government schools and private schools, with government schools suffering severe restrictions on the use of social media and Web 2.0, leading to an unsophisticated use of these technologies. It is argued that internet ‘over-­‐ blocking’ may lead to government school students not being empowered to manage risks in an open internet environment. Furthermore, their use of information for academic and recreational learning may be compromised. This has implications particularly for low socioeconomic students, leading to further inequity in the process and outcomes of Australian education.

Port of Bundaberg Futures

This exhibition showcases the work of Postgraduate Landscape Architecture and final year Undergraduate Civil and Environmental Engineering students in response to issues of sustainability in the Port of Bundaberg. The Port of Bundaberg project site, just north of Bargara, is a complex mix of port facilities, urban development, coastal conservation and agriculture. The project brief was to prepare a range of strategic planning and environmental management options for future urban and infrastructure development in the Port area. Postgraduate Landscape Architecture and final year Undergraduate Civil and Environmental Engineering students worked over one teaching semester with guidance from QUT academics and partner organisations to produce strategic planning, environmental management planning and design options for managing future growth in the area. Specifically, these make recommendations regarding: • Interface between Port lands and residential settlement; • Future residential/urban development; • Transport accessibility and mobility – road, rail, tramway and maritime for personal and freight movement; • Local and regional connectivity - both physical and perceptual- between urban settlements of Port of Bundaberg – Burnett Heads and the surrounding area; • Recreational and tourism development; • Public/private space mix and access; • Ecological conservation assets; • Natural and cultural heritage assets The project process involved three visits to the site by QUT students and staff. The first visit at the project’s commencement included a formal briefing session with project partners the Burnett Mary Regional Group, Port of Brisbane Corporation, and Queensland Department of Local Government and Planning. Formal and informal community engagement facilitated by the Burnett Heads Progress Association also allowed students to gain some understanding of local values. A second visit mid-project involved a ‘Futures Workshop’ with students and community. This enabled the students to gain the benefit of local knowledge and experience in response to their work-in-progress, and to establish priorities for project completion. It strengthened the relationship between the community and the students. A final exhibition, ‘Port of Bundaberg Futures' was held at the Port TAFE Campus upon the completion of the project. The student work exhibited offers a diverse number of alternative options for the future urban development, infrastructure and environmental planning that the partner organisations have used for ongoing consultation.

Bargara Pasturage Reserve : Future Visions

Bargara Pasturage Reserve: Future Visions This exhibition showcases the work of Postgraduate Landscape Architecture and final year Undergraduate Civil and Environmental Engineering students in response to issues of sustainability in a coastal wetland known as the Bargara Pasturage Reserve; an exemplar of the many issues facing sensitive coastal places in Queensland today. The 312ha Pasturage Reserve at Bargara is the only biofilter between the pressures of Bargara’s urban and tourism expansion, surrounding sugarcane farming, and the Great Sandy Marine Park, including the largest concentration of nesting marine turtles on the eastern Australian mainland. This ephemeral wetland, while struggling to fulfil its coastal biofiltration function, is also in high demand for passive recreation, and the project partners’ priorities were to meet both of these challenges. The students were required to plan and design for the best balance possible amongst, but not limited to: wetland and coastal ecological health, enhancement of cultural heritage and values, sustainable urban development, and local economic health. To understand these challenges, QUT staff and students met with partners, visited and analysed the Pasturage Reserve, spent time in and around Bargara talking to locals and inviting dialogue with Indigenous representatives and the South Sea Islander community. We then went home to Brisbane to undertake theoretical and technical research, and then worked to produce 11 Strategic Plans, 2 Environmental Management Plans and 33 Detailed Designs. One group of students analysed the Bargara coastal landscape as an historical and ongoing series of conversations between ecological systems, cultural heritage, community and stakeholders. Another group identified the landscape as neither ‘urban,’ ‘rural,’ nor ‘natural,’ instead identifying it metaphorically as a series of layered thematic ‘fields’ such as water, conservation, reconciliation, and educational fields. These landscape analyses became the organising mechanisms for strategic planning. An outstanding Strategic Plan was produced by Zhang, Lemberg and Jensen, entitled Metanoia, which means to ‘make a change as the result of reflection on values’. Three implementation phases of “flow”, “flux”, and “flex” span twenty-five years, and present a vision a coastal and marine research and conservation hub, with a focus on coastal wetland function, turtle habitat and coral reef conservation. An Environmental Management Plan by Brand and Stickland focuses on protecting and improving wetland biodiversity and habitat quality, and increasing hydrological and water quality function; vital in a coastal area of such high conservation value. After the planning phase, students individually developed detailed design proposals responsive to their plans. From Metanoia, Zhang concentrated on wetland access and interpretation, proposing four focal places to form the nucleus of a wider pattern of connectivity, and to encourage community engagement with coastal environmental management and education. Jensen tackled the thorny issue of coastal urban development, proposing a sensitive staged eco-village model which maintains both ecological and recreational connectivity between the wetland and the marine environment. This project offered QUT’s partners many innovative options to inform their future planning. BSC, BMRG and Oceanwatch Australia are currently engaged in the investigation of on-ground opportunities drawing on these options.

Normative and critical criteria for iliotibial band and iliopsoas muscle flexibility

Context: The Ober and Thomas tests are subjective and involve a "negative" or "positive" assessment, making them difficult to apply within the paradigm of evidence-based medicine. No authors have combined the subjective clinical assessment with an objective measurement for these special tests. Objective: To compare the subjective assessment of iliotibial band and iliopsoas flexibility with the objective measurement of a digital inclinometer, to establish normative values, and to provide an evidence-based critical criterion for determining tissue tightness. Design: Cross-sectional study. Setting: Clinical research laboratory. Patients or Other Participants: Three hundred recreational athletes (125 men, 175 women; 250 in injured group, 50 in control group). Main Outcome Measure(s): Iliotibial band and iliopsoas muscle flexibility were determined subjectively using the modified Ober and Thomas tests, respectively. Using a digital inclinometer, we objectively measured limb position. lnterrater reliability for the subjective assessment was compared between 2 clinicians for a random sample of 100 injured participants, who were classified subjectively as either negative or positive for iliotibial band and iliopsoas tightness. Percentage of agreement indicated interrater reliability for the subjective assessment. Results: For iliotibial band flexibility, the average inclinometer angle was -24.59 degrees +/- 7.27 degrees. A total of 432 limbs were subjectively assessed as negative (-27.13 degrees +/- 5.53 degrees) and 168 as positive (-16.29 degrees +/- 6.87 degrees). For iliopsoas flexibility, the average inclinometer angle was -10.60 degrees +/- 9.61 degrees. A total of 392 limbs were subjectively assessed as negative (-15.51 degrees +/- 5.82 degrees) and 208 as positive (0.34 degrees +/- 7.00 degrees). The critical criteria for iliotibial band and iliopsoas flexibility were determined to be -23.16 degrees and -9.69 degrees, respectively. Between-clinicians agreement was very good, ranging from 95.0% to 97.6% for the Thomas and Ober tests, respectively. Conclusions: Subjective assessments and instrumented measurements were combined to establish normative values and critical criterions for tissue flexibility for the modified Ober and Thomas tests.

Perceived environmental correlates and physical activity: What neighborhood aspects really matter for mothers and fathers of young children?

Limited research has been conducted with at-risk populations in examining perceived environmental correlates of physical activity (PA); thus, we examined this relationship among parents with young children, a group at risk for physical inactivity. Parents (252 mothers, 206 fathers) completed a questionnaire assessing measures of perceived neighborhood environment and a 1-week follow-up of PA behavior. Mothers were more likely than fathers to perceive their neighborhood as unsafe to go for walks at night and less likely to perceive transit stops within 10–15 minutes walking distance, sidewalks on most streets, and facilities to bicycle. Adjusting for demographics, shops within easy walking distance, sidewalks on most streets, and having no more than one motor vehicle were associated with being active for both sexes. Access to transit stops and free/low cost recreational facilities were also associated with mothers’ PA. These findings suggest that environmental factors may support parents being active at recommended levels.

Communicating personal amnesty : a model for health promotion in an Australian disability context

Currently pathological and illness-centric policy surrounds the evaluation of the health status of a person experiencing disability. In this research partnerships were built between disability service providers, community development organizations and disability arts organizations to build a translational evaluative methodology prior to implementation of an arts-based workshop that was embedded in a strengths-based approach to health and well-being. The model consisted of three foci: participation in a pre-designed drama-based workshop program; individualized assessment and evaluation of changing health status; and longitudinal analysis of participants changing health status in their public lives following the culmination of the workshop series. Participants (n = 15) were recruited through disability service providers and disability arts organizations to complete a 13-week workshop series and public performance. The study developed accumulative qualitative analysis tools and member-checking methods specific to the communication systems used by individual participants. Principle findings included increased confidence for verbal and non-verbal communicators; increased personal drive, ambition and goal-setting; increased arts-based skills including professional engagements as artists; demonstrated skills in communicating perceptions of health status to private and public spheres. Tangential positive observations were evident in the changing recreational, vocational and educational activities participants engaged with pre- and post- the workshop series; participants advocating for autonomous accommodation and health provision and changes in the disability service staff's culture. The research is an example of translational health methodologies in disability studies.

Antibiotic resistance and virulence traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates

This study compared virulence and antibiotic resistance traits in clinical and environmental E. faecalis and E. faecium isolates. E. faecalis isolates harboured a broader spectrum of virulence determinants compared to E. faecium isolates. The virulence traits Cyl-A, Cyl-B, Cyl-M, gel-E and esp were tested and environmental isolates predominantly harboured gel-E (80% of E. faecalis and 31.9% of E. faecium) whereas esp was more prevalent in clinical isolates (67.79% of E. faecalis and 70.37 % of E. faecium). E. faecalis and E. faecium isolated from water had different antibiotic resistance patterns compared to those isolated from clinical samples. Linozolid resistance was not observed in any isolates tested and vancomycin resistance was observed only in clinical isolates. Resistance to other antibiotics (tetracycline, gentamicin, ciprofloxacin and ampicillin) was detected in both clinical and water isolates. Clinical isolates were more resistant to all the antibiotics tested compared to water isolates. Multi-drug resistance was more prevalent in clinical isolates (71.18% of E. faecalis and 70.3 % of E. faecium) compared to water isolates (only 5.66 % E. faecium). tet L and tet M genes were predominantly identified in tetracycline-resistant isolates. All water and clinical isolates resistant to ciprofloxacin and ampicillin contained mutations in the gyrA, parC and pbp5 genes. A significant correlation was found between the presence of virulence determinants and antibiotic resistance in all the isolates tested in this study (p<0.05). The presence of antibiotic resistant enterococci, together with associated virulence traits, in surface recreational water could be a public health risk.

The Art of Freestyle

"This book is intended to be instructional, inspirational and of interest to both novice and expert alike. The assumption is made that to even begin to playboat the paddler will already be an intermdiate white water boater familiar with basic strokes and boating skills. For the interested non paddler a glossary of terms is included. Part One gives an overview of the sport and lays the foundations of understanding on which the rest of the book builds, as well as exploring safety issues and exploring key concepts. Part Two describes and coaches the moves which are divided into intermediate and advanced standard. Part Three looks at how to train in order to hone your physical and mental skills and be 'the best you can be'. Never before has so much freestyle, rodeo and playboating information from so many great boaters been gathered together in one place. In a world dominated by the biggest, the fastest, the loudest...the most big headed, this book makes a stand. Whilst of course covering all the latest moves, the authors have not been frightened to start right back at basic concepts. Technical ability is nothing without knowledge, without planning and without stamina. This book tells you the secrets. Freestyle is a thinking person's sport. The authors, the contributors and the book's publisher have an unrivalled breadth of knowledge in this field, so let this book do some of the thinking for you. The full colour format and the emphasis on personal training and coaching make for a particularly easy read. When planning my preparation or training before a competition, I always try to evaluate its potential benefits in terms of how many places it will have helped me move up in the final results. As a general rule in life, any time spent off the water should be viewed with suspicion! However, use this time constructively and absorb the information in this book and you will reap your own rewards. The Art of Freestyle is a book genuinely written by paddlers for paddlers. It is often a hard task to get top athletes to part with their preferred training or competition techniques, but this book is full of such 'Top Tips'. This is not a book written just by its authors, but by a wealth of accomplished paddlers. It is this subtle combination that keeps the reader in the real world...believing in a move, not just imagining it. This is the real world...believe you can do it."--Playak Website