Sitting-time, physical activity and depressive symptoms in mid-aged women

Background: Associations between sitting-time and physical activity (PA) with depression are unclear. Purpose: To examine concurrent and prospective associations between both sitting-time and PA with prevalent depressive symptoms in mid-aged Australian women. Methods: Data were from 8,950 women, aged 50-55 years in 2001, who completed mail surveys in 2001, 2004, 2007 and 2010. Depressive symptoms were assessed using the Center for Epidemiological Studies Depression questionnaire. Associations between sitting-time (≤4, >4-7, >7 hrs/day) and PA (none, some, meeting guidelines) with depressive symptoms (symptoms/no symptoms) were examined in 2011 in concurrent and lagged mixed effect logistic modeling. Both main effects and interaction models were developed. Results: In main effects modeling, women who sat >7 hrs/day (OR 1.47, 95%CI 1.29-1.67) and women who did no PA (OR 1.99, 95%CI 1.75-2.27) were more likely to have depressive symptoms than women who sat ≤4 hrs/day and who met PA guidelines, respectively. In interaction modeling, the likelihood of depressive symptoms in women who sat >7 hrs/day and did no PA was triple that of women who sat ≤4 hrs/day and met PA guidelines (OR 2.96, 95%CI 2.37-3.69). In prospective main effects and interaction modeling, sitting-time was not associated with depressive symptoms, but women who did no PA were more likely than those who met PA guidelines to have future depressive symptoms (OR 1.26, 95%CI 1.08-1.47). Conclusions: Increasing PA to a level commensurate with PA guidelines can alleviate current depression symptoms and prevent future symptoms in mid-aged women. Reducing sitting-time may ameliorate current symptoms.

Changes in neutrophil surface receptor expression, degranulation, and respiratory burst activity after moderate- and high-intensity exercise

Intense exercise stimulates the systemic release of a variety of factors that alter neutrophil surface receptor expression and functional activity. These alterations may influence resistance to infection after intense exercise. The aim of this study was to examine the influence of exercise intensity on neutrophil receptor expression, degranulation (measured by plasma and intracellular myeloperoxidase concentrations), and respiratory burst activity. Ten well-trained male runners ran on a treadmill for 60 min at 60% [moderate-intensity exercise (MI)] and 85% maximal oxygen consumption [high-intensity exercise (HI)]. Blood was drawn immediately before and after exercise and at 1 h postexercise. Immediately after HI, the expression of the neutrophil receptor CD16 was significantly below preexercise values (P < 0.01), whereas MI significantly reduced CD35 expression below preexercise values (P < 0.05). One hour after exercise at both intensities, there was a significant decline in CD11b expression (P < 0.05) and a further decrease in CD16 expression compared with preexercise values (P < 0.01). CD16 expression was lower 1 h after HI than 1 h after MI (P < 0.01). Immediately after HI, intracellular myeloperoxidase concentration was less than preexercise values (P < 0.01), whereas plasma myeloperoxidase concentration was greater (P < 0.01), indicating that HI stimulated neutrophil degranulation. Plasma myeloperoxidase concentration was higher immediately after HI than after MI (P < 0.01). Neutrophil respiratory burst activity increased after HI (P < 0.01). In summary, both MI and HI reduced neutrophil surface receptor expression. Although CD16 expression was reduced to a greater extent after HI, this reduction did not impair neutrophil degranulation and respiratory burst activity.

Exercise-induced alterations in neutrophil degranulation and respiratory burst activity : possible mechanisms of action

Neutrophils constitute 50-60% of all circulating leukocytes; they present the first line of microbicidal defense and are involved in inflammatory responses. To examine immunocompetence in athletes, numerous studies have investigated the effects of exercise on the number of circulating neutrophils and their response to stimulation by chemotactic stimuli and activating factors. Exercise causes a biphasic increase in the number of neutrophils in the blood, arising from increases in catecholamine and cortisol concentrations. Moderate intensity exercise may enhance neutrophil respiratory burst activity, possibly through increases in the concentrations of growth hormone and the inflammatory cytokine IL-6. In contrast, intense or long duration exercise may suppress neutrophil degranulation and the production of reactive oxidants via elevated circulating concentrations of epinephrine (adrenaline) and cortisol. There is evidence of neutrophil degranulation and activation of the respiratory burst following exercise-induced muscle damage. In principle, improved responsiveness of neutrophils to stimulation following exercise of moderate intensity could mean that individuals participating in moderate exercise may have improved resistance to infection. Conversely, competitive athletes undertaking regular intense exercise may be at greater risk of contracting illness. However, there are limited data to support this concept. To elucidate the cellular mechanisms involved in the neutrophil responses to exercise, researchers have examined changes in the expression of cell membrane receptors, the production and release of reactive oxidants and more recently, calcium signaling. The investigation of possible modifications of other signal transduction events following exercise has not been possible because of current methodological limitations. At present, variation in exercise-induced alterations in neutrophil function appears to be due to differences in exercise protocols, training status, sampling points and laboratory assay techniques.

Interval training program optimization in highly trained endurance cyclists

PURPOSE: The purpose of this study was to examine the influence of three different high-intensity interval training (HIT) regimens on endurance performance in highly trained endurance athletes. METHODS: Before, and after 2 and 4 wk of training, 38 cyclists and triathletes (mean +/- SD; age = 25 +/- 6 yr; mass = 75 +/- 7 kg; VO(2peak) = 64.5 +/- 5.2 mL x kg(-1) min(-1)) performed: 1) a progressive cycle test to measure peak oxygen consumption (VO(2peak)) and peak aerobic power output (PPO), 2) a time to exhaustion test (T(max)) at their VO(2peak) power output (P(max)), as well as 3) a 40-km time-trial (TT(40)). Subjects were matched and assigned to one of four training groups (G(2), N = 8, 8 x 60% T(max) at P(max), 1:2 work:recovery ratio; G(2), N = 9, 8 x 60% T(max) at P(max), recovery at 65% HR(max); G(3), N = 10, 12 x 30 s at 175% PPO, 4.5-min recovery; G(CON), N = 11). In addition to G(1), G(2), and G(3) performing HIT twice per week, all athletes maintained their regular low-intensity training throughout the experimental period. RESULTS: All HIT groups improved TT(40) performance (+4.4 to +5.8%) and PPO (+3.0 to +6.2%) significantly more than G(CON) (-0.9 to +1.1%; P < 0.05). Furthermore, G(1) (+5.4%) and G(2) (+8.1%) improved their VO(2peak) significantly more than G(CON) (+1.0%; P < 0.05). CONCLUSION: The present study has shown that when HIT incorporates P(max) as the interval intensity and 60% of T(max) as the interval duration, already highly trained cyclists can significantly improve their 40-km time trial performance. Moreover, the present data confirm prior research, in that repeated supramaximal HIT can significantly improve 40-km time trial performance.

The great divide : bridging the gap

Learning Objective: To describe a collaborative system of clinical allocations using a dedicated, discipline specific administrative coordinator. Methods: The Clinical Placement Coordinator is the liaison person between the student, the academic staff and the clinical sites, and fills an important role in bridging the gap to enhance the student learning experience. With this in mind the Coordinator is very discipline focused and works closely with the academic staff who coordinate the clinical units within the program. This person is the ‘‘face’’ of QUT to the external stakeholders, and ensures that all parties experience a smooth process. This no mean feat given that there are over 350 students to be placed annually, across 14 separate clinical blocks ranging from 1 to 6 weeks in length at various sites. The processes involved in clinical placement allocation will be presented, and the roles of the staff in facilitating students’ placement preferences and matching with clinical site offers will be described. In many allied health programs in Australia, the clinical placement activity is carried out by an academic member of staff. However, this can result in delays in communications due to other workload requirements such as lecture, tutorial and practical class commitments. Having a dedicated knowledgeable administration officer has resulted in a person being available to take calls from clinical staff, meet with students to discuss allocation needs and ensure that academic staff are consulted if and when necessary. The Clinical Placement Coordinator is very much a part of the course team and attends professional meetings and conferences as an avenue of networking and meeting clinical staff. Results: The success in having a dedicated administrative officer as the Clinical Placement Coordinator acting as the conduit between academic staff and students, and the university and clinical staff has been highly successful to date. This was noted in commendations from the 2010 Course Accreditation Panel Report which stated: ‘‘The very positive perception in the professional community of Ms Margaret McBurney’s effective and efficient organization of student clinical placements. Students and clinical professionals commented favourably on the approachability of staff. There is confidence that program staff will follow up on issues raised urgently in clinical centres.’’

Australian adolescents’ perceived school-based barriers and facilitators to engagement in physical activity

OBJECTIVE: School-aged youth spend a significant amount of time either in transit to and from school, or within school settings performing a range of varying learning-based activities. Adolescent physical activity has also been shown to increase the likelihood of maintaining physical activity throughout adulthood. The purpose of this study is to investigate adolescents’ perceived school-based barriers and facilitators to engagement in physical activity. METHODS: One-hundred and twenty four participants (38 males and 86 females) were recruited from two non-denominational same-sex private schools, in Brisbane, Australia. The mean age and standard deviation (SD) was 13.83 (0.56) and 14.40 (2.33) for males and females respectively. Participants responded to a series questions regarding perceived barriers and facilitators to engagement in physical activity. Quantitative data was analysed using descriptive statistics and frequency distributions, and qualitative data with thematic analysis. RESULTS: A total of 121 (97.6%) participants had complete data sets and were included in the analysis. School timetable (44.6%), homework (81.8%), and assessment (81.0%) were identified as the most prominent perceived factors, increasing the difficulty of physical activity engagement. Physical Education classes (71.9%) and school sport programs (80.2%) were identified as the most prominent perceived factors that facilitate engagement in physical activity. There was no significant gender effect. CONCLUSIONS: Each of the identified factors perceived by adolescent's as either barriers or facilitators to engagement in physical activity may be addressed by administrators at a school and government policy level. These may include strategies such as; increasing the assigned hours to physical education classes, providing additional extra-curricular sporting opportunities, and reviewing the time allocated to homework and assessment items. This may provide a simpler, low-cost solution to increasing youth physical activity, as opposed to contemporary higher-cost strategies utilising increased staff commitment, mass media, provision of equipment and counsellors and other health professionals.

Passenger experience at airports : An activity-centred approach

This project has provided a new understanding of the passenger experience in Australian international airport departure terminals. A novel understanding of the passenger experience developed by observing the activities passengers carried out on their day of travel, and interviewing passengers and staff members. The development of the Taxonomy of Passenger Activities (TOPA) has been an important outcome of this research. It provides a new understanding of the airport passenger experience at departure. The Taxonomy of Passenger Activities identifies the activities that improve the experience of passengers and the processing efficiency of the airport terminal.

Program-level support for protecting an application from untrustworthy components

Many software applications extend their functionality by dynamically loading executable components into their allocated address space. Such components, exemplified by browser plugins and other software add-ons, not only enable reusability, but also promote programming simplicity, as they reside in the same address space as their host application, supporting easy sharing of complex data structures and pointers. However, such components are also often of unknown provenance and quality and may be riddled with accidental bugs or, in some cases, deliberately malicious code. Statistics show that such component failures account for a high percentage of software crashes and vulnerabilities. Enabling isolation of such fine-grained components is therefore necessary to increase the stability, security and resilience of computer programs. This thesis addresses this issue by showing how host applications can create isolation domains for individual components, while preserving the benefits of a single address space, via a new architecture for software isolation called LibVM. Towards this end, we define a specification which outlines the functional requirements for LibVM, identify the conditions under which these functional requirements can be met, define an abstract Application Programming Interface (API) that encompasses the general problem of isolating shared libraries, thus separating policy from mechanism, and prove its practicality with two concrete implementations based on hardware virtualization and system call interpositioning, respectively. The results demonstrate that hardware isolation minimises the difficulties encountered with software based approaches, while also reducing the size of the trusted computing base, thus increasing confidence in the solution’s correctness. This thesis concludes that, not only is it feasible to create such isolation domains for individual components, but that it should also be a fundamental operating system supported abstraction, which would lead to more stable and secure applications.

Primary classroom teachers' use of social and emotional wellbeing programs and the factors influencing program use

There has been a rapid escalation in the development and evaluation of social and emotional well-being (SEW) programs in primary schools over the last few decades. Despite the plethora of programs available, primary teachers’ use of SEW programs is not well documented in Australian schools, with even less consideration of the factors influencing program use. A cross-sectional survey was undertaken with primary classroom teachers across twelve schools in the Brisbane and Sunshine Coast Education Districts in Queensland, Australia, during 2005. A checklist of SEW programs and an audit of SEW practices in schools were employed to investigate the number, range and types of SEW programs used by primary classroom teachers and the contextual factors influencing program use. Whilst the majority of implementation studies have been conducted under intervention conditions, this study was designed to capture primary classroom teachers’ day-to-day use of SEW programs and the factors influencing program use under real-world conditions. The findings of this research indicate that almost three quarters of the primary classroom teachers involved in the study reported using at least one SEW program during 2005. Wide variation in the number and range of programs used was evident, suggesting that teachers are autonomous in their use of SEW programs. Evidence-based SEW programs were used by a similar proportion of teachers to non-evidence-based programs. However, irrespective of the type of program used, primary teachers overwhelmingly reported using part of a SEW program rather than the whole program. This raises some issues about the quality of teachers’ program implementation in real-world practice, especially with respect to programs that are evidence-based. A content analysis revealed that a wide range of factors have been examined as potential influences on teachers’ implementation of health promotion programs in schools, including SEW programs, despite the limited number of studies undertaken to date. However, variation in the factors examined and study designs employed both within and across health promotion fields limited the extent to which studies could be compared. A methodological and statistical review also revealed substantial variation in the quality of reporting of studies. A variety of factors were examined as potential influences on primary classroom teachers’ use of SEW programs across multiple social-ecological levels of influence (ranging from community to school and individual levels). In this study, parent or caregiver involvement in class activities and the availability of wellbeing-related policies in primary schools were found to be influential in primary classroom teachers’ use of SEW programs. Teachers who often or always involve parents or caregivers in class activities were at a higher odds of program use relative to teachers who never or rarely involved parents or caregivers in class activities. However, teachers employed in schools with the highest number of wellbeing-related policies available were at a lower odds of program use relative to teachers employed in schools with fewer wellbeing-related policies available. Future research should investigate primary classroom teachers’ autonomy and motivations for using SEW programs and the reasons behind the selection and use of particular types of programs. A larger emphasis should also be placed upon teachers not using SEW programs to identify valid reasons for non-use. This would provide another step towards bridging the gap between the expectations of program developers and the needs of teachers who implement programs in practice. Additionally, the availability of wellbeing-related school policies and the types of activities that parents and caregivers are involved with in the classroom warrant more in-depth investigation. This will help to ascertain how and why these factors influence primary classroom teachers’ use of SEW programs on a day-to-day basis in schools.

Establishing design thinking : accident, program frameworks and personal practices

Distribution through electronic media provides an avenue for promotion, recognition and an outlet of display for graphic designers. The emergence of available media technologies have enabled graphic designers to extend these boundaries of their practice. In this context the designer is constantly striving for aesthetic success and is strongly influenced by the fashion and trends of contemporary design work. The designer is always in a state of inquiry, finding pathways of discovery that lead to innovation and originality that are highly valued criteria for self-evaluation. This research is based on an analysis of the designer perspective and the processes used within an active graphic design practice specializing entirely within a digital collage domain. Contemporary design methodologies were critically examined, compared and refined to reflect the self-practice of the researcher. The refined methodology may assist designers in maintaining systematic work practices, as well as promote the importance of exploration and experimentation processes. Research findings indicate some differences in the identified methodologies and the design practice of the researcher in the sense that many contemporary designers are not confined to a client-base but are self-generating design images influenced by contemporary practitioners. As well as confirming some aspects of more conventional design processes, the researcher found that accidental discoveries and the designer’s interaction with technology plays a significant part in the design process.

Effects of introducing an interactive teaching and learning activity (TLA) in the engineering classroom

This research study examines qualitatively and quantitatively the influence of introducing an activity in the traditional engineering classroom. It studies instances of active learning and its relationship with the student learning outcomes. The primary purpose of this study was to compare the learning outcomes of students who were involved in an active TLA with those students who were not, instead they learned under traditional teaching and studying approaches. I present the argument that the introduction of a TLA in class stimulates student engagement bringing enormous benefits to student learning. The outcomes of this study were measured using qualitative and quantitative data to evaluate the levels of student engagement, achievement and satisfaction in the terms of Intended Learning Outcomes (ILOs). Results indicate that students held positive attitude towards the activities in class and also, that a positive link between TLA, learning approach and learning outcome exist. It also provides insights about the potential benefits of active learning when compared with traditional, passive and teacher-centred methods of teaching & learning.

Perception and reality : meeting Australia’s physical activity guidelines for 12-18 year olds

Governments regularly publish empirically derived minimum physical activity (PA) guidelines for youth, in response to the ongoing trend of youth physical inactivity. The purpose of this investigation was to explore parents’ awareness of the national PA guidelines for youth, and adolescents’ and their parents’ perceptions of adolescent PA, and compare these to self-reported adolescent PA. A total of 115 adolescents (aged 12-14) and their parents completed questionnaire assessments. Parents responded to questions concerning their awareness of the national PA guidelines, and whether they believed their child to be sufficiently active. Adolescents completed the International Physical Activity Questionnaire for Adolescents, and questions concerning their perceived level of PA. Adolescents were deemed sufficiently active if they participated in an average of at least 60 minutes of moderate-to-vigorous PA each day. Overall, 104 (90.4%) adolescents and their parents had complete data sets and were included in the analysis. Of the 45 (43.3%) sufficiently and 59 (56.7%) insufficiently active adolescents, 42 (93%) and 41 (69.5%) respectively believed that they were active enough for good general health. Additionally, 41 (91.1%) parents of active and 44 (74.6%) parents of inactive adolescents either agreed or strongly agreed that their child participates in sufficient PA for good general health. Twenty-four (53.3%) parents of active adolescents were unaware of the national PA guidelines, with 10 (22.2%) neither aware or unaware, and 11 (24.4%) aware. Similar results were found for the parents of inactive adolescents with 31 (52.5%) unaware, 17 (28.8%) neither aware or unaware, and 11 (18.6%) aware. These results suggest that the youth PA guidelines are being inadequately received by both adolescents, and their parents. Opportunities to effectively communicate these guidelines such as embedment in curriculum for adolescents, or the dissemination of materials for parents, should be maximised by appropriate authorities.

Pre-service Physical Education teachers and concerns regarding their ability to successfully facilitate school-based physical activity promotion strategies

Regular physical activity (PA) in youth has numerous immediate and long-term health benefits. With several studies indicating low levels of youth PA globally, schools settings have become increasingly critical settings for youth health promotion strategies. The role of physical education (PE) teachers has long been considered central to the facilitation of such strategies. However, PE teachers have a selfreported lack of knowledge, skills, understanding, and competence to successfully implement these strategies. Tertiary education programs are fundamental to adequately preparing, and shaping the attitudes and philosophies of future PE teachers towards their involvement within these programs. The aim of this investigation was to explore the beliefs and perceptions of future secondary school PE teachers, regarding their potential roles in future school-based programs designed to promote student PA. Fifty-seven (21 males and 36 females) pre-service PE teachers completed a series of open-ended survey questions concerning their perceptions towards participating in school-based PA promotion programs both as preservice during practicum, and prospectively as practising teachers. Responses were analysed thematically. Participants responded both positively and enthusiastically to both questions. Concerns regarding time, and the intention or expectation to participate in such programs were also key themes for pre-service and practicing teacher participation respectively. Critically in this study, participants did not identify any limitations which may impact upon their ability to successfully promote youth PA in school settings. This may indicate that participants have misconceptions regarding their ability to fulfil this role, or conversely, the deficiency of current PE teachers regarding school-based PA promotion has been recognised by the tertiary institution, and addressed to adequately prepare its students. School-based PA promotion is an integral element of pre-service PE teacher education, and ongoing professional development of practicing PE teachers. This trend is expected to continue in the future, in order to address ongoing public health concerns.

Do adolescents ‘like’ the use of social networking and associated technologies for physical activity promotion?

Physical activity has been identified as a key behaviour in determining an individual’s health and functioning. Adolescent physical inactivity has been shown to track strongly through to adulthood. Interventions in youth to promote and increase physical activity have had mixed results. The significant rise over the past decade in time spent by adolescents performing social networking may provide a unique opportunity for health promoters to interact with adolescents through a familiar medium. The purpose of was study is to investigate the potential utility of social networking and associated technologies for the promotion of physical activity amongst adolescents. Participants were recruited from two nondenominational same-sex private schools, from high socioeconomic backgrounds in Brisbane, Australia. A total of 112 (90.3%) participants had complete data sets and were included in the analysis. Account ownership and rates of access to some social networking sites were high. However, a combination of a lack of interest and additional risks associated with social networking utilities, means that caution should be undertaken prior to the commencement of any intervention seeking to increase engagement in physical activities through these mediums. Student smart phone access and interest in smart phone applications for physical activity promotion purposes were moderate, and may provide opportunities for samples of adolescents from high socioeconomic backgrounds who are more likely to have access to appropriate technologies. As technology advances, the rate of smart phone ownership as opposed to overall phone ownership is likely to steadily increase over time. Access and use of information technology by children likely to continue to become more convenient. This makes smart phone applications as a means for physical activity promotion progressively more practical, and a promising future option.