Examining Single Session Peer-Teaching Instructional Approaches on Pre-Service Physical Education Teachers' Throwing Techniques

An important role of a Physical Education (PE) teacher is to assist students to develop the fundamental motor skills (FMS) that will allow them to participate in physical activities with competence and confidence. Thus, PE teachers require the knowledge and skills to carry out this crucial task. In the crowded curricula of Physical Education Teacher Education (PETE) programs, there are limited opportunities for pre-service PE teachers to learn how to analyze and perform a large list of motor skills. Our purposes in this study were to determine whether a single session peer-teaching intervention could improve pre-service PE teachers' short-term non-dominant hand overarm throwing performances and to examine these students' perceptions of the interventions. We allocated 47 pre-service PE teaching students (24 males; 23 females) to one of three experimental groups: a Video Analysis Group (VAG; n = 17), a Verbal Group (VG; n = 19), and a Control Group (CG; n = 11), based on the class in which they were enrolled. VAG and VG participants worked with a partner of their choice in reciprocal peer-teaching to improve each other's non-dominant hand throwing technique. VAG and VG interventions were identical except that VAG participants accessed video analysis technology. CG participants completed unrelated course work that involved no overarm throwing activities. A single 20-minute session of peer teaching with video analysis feedback during practice led to rapid enhancements in non-dominant hand overarm throwing skills. While all three groups improved their performance by retention testing, participants in the VAG group improved most quickly. Participants in both the VAG and VG groups reported that their respective interventions improved their throwing and Qualitative Movement Diagnosis (QMD) skills. Based on these results, we suggest that PETE programs integrate peer-teaching and video analysis sessions into fundamental movement courses to accelerate students' motor skill acquisitions.

Non-response bias in estimates of prevalence of club-based sport participation from an Australian national physical activity, recreation and sport survey

Background

An estimate of the prevalence of an activity derived from a sample survey is potentially subject to non-response bias, whereby people not involved in the activity are less likely to respond than those involved. Quantifying the extent of non-response bias is generally difficult, since it involves estimating differences between respondents for whom data is directly available from the survey, and non-respondents, for whom data is generally not directly or readily available. However, in the case of the Australian Exercise Recreation and Sport Survey (ERASS), comparative “gold standard” benchmarks exist for some aspects of the survey, in the form of state sporting association (SSA) registration databases, each of which purports to constitute a complete enumeration of club-based players of a particular sport.

Methods

ERASS estimates of the prevalence of participation in four major club-based team sports in the Australian state of Victoria in the year 2010 were compared with prevalences based on numbers of registered participants in the corresponding SSA databases. Comparisons were made for the adult population as a whole (ERASS scope being 15+ years of age), and for strata defined by age and geographical region. Because three of the four sports investigated are strongly sex-specific, no sex breakdowns were conducted. In each case the proportion of ERASS respondents reporting participation, with associated confidence limits, was compared with the corresponding SSA count expressed as a proportion of the population, to form an ERASS/SSA prevalence ratio with associated confidence limits.

Results

The 24 ERASS/SSA ratios ranged from 1.72 to 7.80. Most ratios lay in the range 2 to 3. The lower 95% confidence bound for the ratio was greater than 1.0 in 23 out of 24 cases.

Conclusions

ERASS estimates of prevalence of these particular aspects of sport participation were higher than SSA estimates, to statistically significant degrees. The effect sizes (i.e. the discrepancies represented by the ratios) were large enough to be of great practical importance. It is conjectured that non-response bias is the most likely explanation for the discrepancies.

Demographic characteristics and type/frequency of physical activity participation in a large sample of 21,603 Australian people

BACKGROUND

Regular physical activity (PA) is imperative for good health and there are many different ways that people can be active. There are a range of health, PA and sport policies aiming to get more people active more often. Much research has been directed towards understanding the determinants of inactivity and PA. However, it is important to understand the differences not only between inactive and active people, but also between activity contexts (for example participation in sport compared to non-sport activities), in order to align policies and strategies to engage market segments who have different participation preferences and accessibility. The aim of this study was to investigate demographic correlates of the propensity to be physically inactive or active within different contexts, and at different levels of frequency of participation.

METHODS

Data from the Australian Exercise, Recreation and Sport Survey was used for this analysis. This included information on the type, frequency and duration of leisure-time PA for Australians aged 15 years and over. Reported PA participation in the two-week period prior to the survey was used to allocate respondents into three categories: no PA, non-sport PA only, and sport. Subsequently, sport participants were further categorised according to frequency of participation. Potential demographic correlates included sex, age, education, employment, marital status, language spoken, having a condition that restricts life, children, and socio-economic status.

RESULTS

The survey included 21,603 people. Bivariate chi-squared analysis showed that there were significant differences between the profiles of leisure-time PA participation across all demographic variables, except the variable languages spoken at home. Ordinal regression analysis showed that the same demographic variables were also correlated with the propensity to engage in more organised and competitive PA contexts, and to participate more frequently.

CONCLUSIONS

People who were female, older, married or had a disability were less likely to participate in sport. Therefore when designing PA opportunities to engage those who are inactive, particularly those that are organised by a club or group, we need to ensure that appropriate strategies are developed, and tailored sport products offered, to ensure greater opportunities for increased diversity of participation in sport.

Participant characteristics of users of holistic movement practices in Australia

OBJECTIVES

The aim of this study was to compare the characteristics of users of holistic movement practices in Australia to people who were physically active but not using holistic movement practices. A second aim was to compare characteristics of users of specific holistic movement practices (yoga/Pilates and t'ai chi/qigong).

DESIGN

We performed a secondary data analysis on pooled data of a nationally-representative physical activity survey conducted yearly 2001-2010 (n = 195,926).

SETTING

Australia-wide Exercise, Recreation, and Sport Survey (ERASS).

MAIN OUTCOME MEASURES

A range of socio-demographic and participation characteristics were documented and compared between users and non-users of holistic movement practices and between yoga/Pilates and t'ai chi/qigong users, employing descriptive statistics, chi square, and multiple logistic regression analyses.

RESULTS

Users of holistic movement practices (n = 6826) were significantly more likely than non-users to be female, older, have fewer children at home, and have higher levels of education, socio-economic background, and physical activity involvement (p < 0.001). Yoga/Pilates (n = 5733) and t'ai chi/qigong (n = 947) users were also found to differ on a number of characteristics, including age, sex, socioeconomic background, and marital status.

CONCLUSION

As a group, Australian users of holistic movement practices differ on a range of characteristics from those Australians active in other types of physical activities. However, differences between yoga/Pilates and t'ai chi/qigong users suggest these practices attract somewhat different sub-populations. To what extent these differences are due to characteristics inherent to the practices themselves or to differences in delivery-related parameters needs to be examined in future research.

Assessment and monitoring practices of Australian fitness professionals

OBJECTIVES

Assessment and monitoring of client health and fitness is a key part of fitness professionals' practices. However, little is known about prevalence of this practice. This study describes the assessment/monitoring practices of a large sample of Australian fitness professionals.

DESIGN

Cross-sectional.

METHODS

In 2014, 1206 fitness professionals completed an online survey. Respondents reported their frequency (4 point-scale: [1] 'never' to [4] 'always') of assessment/monitoring of eight health and fitness constructs (e.g. body composition, aerobic fitness). This was classified as: (i) 'high' ('always' assessing/monitoring ≥5 constructs); (ii) 'medium' (1-4 constructs); (iii) 'low' (0 constructs). Classifications are reported by demographic and fitness industry characteristics. The odds of being classified as a 'high assessor/monitor' according to social ecological correlates were examined using a multiple-factor logistic regression model.

RESULTS

Mean age of respondents was 39.3 (±11.6) years and 71.6% were female. A total of 15.8% (95% CI: 13.7%-17.9%) were classified as a 'high' assessor/monitor. Constructs with the largest proportion of being 'always' assessed were body composition (47.7%; 95% CI: 45.0%-50.1%) and aerobic fitness (42.5%; 95% CI: 39.6%-45.3%). Those with the lowest proportion of being 'always' assessed were balance (24.0%; 95% CI: 24.7%-26.5%) and mental health (20.2%; 95% CI: 18.1%-29.6%). A perceived lack of client interest and fitness professionals not considering assessing their responsibility were associated with lower odds of being classified as a 'high assessor/monitor'.

CONCLUSIONS

Most fitness professionals do not routinely assess/monitor client fitness and health. Key factors limiting client health assessment and monitoring include a perceived lack of client interest and professionals not considering this their role.

Participation trends in holistic movement practices: a 10-year comparison of yoga/Pilates and t'ai chi/qigong use among a national sample of 195,926 Australians

BACKGROUND

In recent decades, the evidence supporting the physical and mental health benefits of holistic movement practices such as yoga and t'ai chi have become increasingly established. Consequently, investigating the participation prevalence and patterns of these practices is a relevant pursuit in the public health field. Few studies have provided population-level assessment of participation rates, however, and even fewer have focused on patterns over time. The purpose of this study was to examine participation prevalence and trends in yoga/Pilates and t'ai chi/qigong over a ten-year period in a nationally representative sample of Australians aged 15 years and over, with particular attention to sex and age. A secondary purpose was to juxtapose these findings with participation trends in traditional fitness activities over the same period.

METHODS

Data comprised modes and types of physical activity, age, and sex variables collected through the Exercise, Recreation and Sport Survey (ERASS), a series of independent cross-sectional Australia-wide surveys conducted yearly between 2001 and 2010. For each year, weighted population estimates were calculated for those participating in yoga/Pilates, t'ai chi/qigong, and fitness activities (e.g. aerobics, calisthenics). Linear regression and multiple logistic regression analyses were used to examine trends in prevalence rates over time and differences among sex and age (15-34; 35-54; 55+ years) groups, respectively.

RESULTS

Average prevalence rates between 2001 and 2010 were 3.0% (95% CI 2.9-3.1) for yoga/Pilates, 0.6% (95% CI 0.5-0.6) for t'ai chi/qigong, and 19.2% (95% CI 18.9-19.4) for fitness activities. Across the decade, overall participation rates remained relatively stable for yoga/Pilates and t'ai chi/qigong, while increasing linearly for fitness activities. For both genders and in all three age groups, participation in fitness activities increased, whereas only in the 55+ age group was there a significant increase in yoga/Pilates participation; participation in t'ai chi/qigong declined significantly in the two younger age groups.

CONCLUSIONS

Participation rates in yoga/Pilates and t'ai chi/qigong in Australia were low and relatively stable. As fitness activities increased in popularity across the decade, holistic movement practices did not. These findings point to the need to investigate activity-specific barriers and facilitators to participation, including intrapersonal, interpersonal, organisational, and environmental factors.

The influence of a Healthy Welcoming Environment on participation in club sport by adolescent girls: a longitudinal study

Background

This study investigated the perceived influence of a Healthy Welcoming Environment (HWE) on participation in sports clubs among adolescent girls, and how these perceptions changed longitudinally. HWE was defined in terms of a set of health promotion policies advocated by a health promotion foundation as the basis of sport club health promotion practice to promote structural reform in state sporting organisations and their affiliated associations and clubs. These included sports injury prevention, smoke-free, responsible serving of alcohol, sun protection, healthy eating, and welcoming and inclusive environments.

Methods

Year 7 and 11 female students from metropolitan (n = 17) and non-metropolitan secondary schools (n = 14) in Australia were invited to participate in three annual surveys. These surveys collected information about current or past membership of a sports club and the influence of HWEs on their decision to participate (or not) in a sports club.

Results

Year 7 (n = 328; 74.5%) and Year 11 (n = 112; 25.5%) female students completed all three waves (19.6% response rate; 82.7 and 74.0% retention rate). Most agreed that characteristics of HWEs were a positive influence on their participation in sports clubs, except those relating to alcohol and Sunsmart. Welcoming factors had consistent high agreement among respondents. Alcohol and friendliness factors of the club were regarded as being positively influential by higher percentages of non-metropolitan than metropolitan respondents.

Conclusions

Welcoming factors were the most positive influences on decisions to participate in sports clubs. These factors may be important in reducing barriers to sport participation. Strategies supporting the social environment within sports clubs should be prioritised.

Sources of practice knowledge among Australian fitness trainers

Few studies have examined the sources of practice knowledge fitness trainers use to inform their training methods and update knowledge. This study aims to describe sources of practice knowledge among Australian fitness trainers. In July 2014, 9100 Australian fitness trainers were invited to complete an online survey. Respondents reported the frequency of use of eight sources of practice knowledge (e.g. fitness magazines, academic texts). In a separate survey, exercise science experts (n = 27) ranked each source as either (1) 'high-quality' or (2) 'low-quality'. Proportions of users of 'high-quality' sources were calculated across demographic (age, sex) and fitness industry-related characteristics (qualification, setting, role). A multivariate logistic regression analysis assessed the odds of being classified as a user of high-quality sources, adjusting for demographic and fitness industry-related factors. Out of 1185 fitness trainers (response rate = 13.0%), aged 17-72 years, 47.6% (95% CI, 44.7-50.4%) were classified as frequent users of high-quality sources of practice knowledge. In the adjusted analysis, compared to trainers aged 17-26 years, those aged ≥61 years (OR, 2.15; 95% CI, 1.05-4.38) and 40-50 years (OR, 1.54; 95% CI, 1.02-2.31) were more likely to be classified as a user of high-quality sources. When compared to trainers working in large centres, those working in outdoor settings (OR, 1.81; 95% CI, 1.23-2.65) and medium centres (OR, 1.59; 95% CI, 1.12-2.29) were more likely to be classified as users of high-quality sources. Our findings suggest that efforts should be made to improve the quality of knowledge acquisition among Australian fitness trainers.

Population levels of sport participation: implications for sport policy

Background

Participation in sport can contribute to health-enhancing levels of leisure-time physical activity. There are recent reports that participation in sport in Australia is decreasing. However, these studies are limited to ages 15 years and over.

Methods

This study integrates sports club membership data from five popular team sports and investigates sport participation across the lifespan (4–100 years) by sex and region (metropolitan/non-metropolitan).

Results

Overall participant numbers per annum increased from 414,167 in 2010 to 465,403 in 2012 corresponding to a rise in the proportion of Victorian’s participating in these sports from 7.5 % in 2010 to 8.3 % in 2012. The highest proportion of participants was in the 10–14 year age range, with participation rates of 36 % in 2010 and 40 % in 2012. There was a considerably lower participation rate in the 15–19 year age group compared to the 10–14 age group, in all three years studied, and the decline continued progressively with increasing age. Male and female age profiles of participation were generally similar in shape, but the female peak at age 10–14 was sharper than for the males, and conversely there were very few 4 year old female participants. Participation rates were generally higher in non-metropolitan than metropolitan areas; the difference increased with increasing age from 4 to 34 years, then steadily declined, reaching parity at around 60 years of age.

Conclusions

It is a positive sign that participation in these popular sports increased by over 50,000 participants from 2010 to 2012. Large proportions of the population aged 5–14 participate in club based sport. Participation rates decline sharply in late adolescence, particularly for females, and while this may not be a concern from a broad health perspective so long as they transition into other forms of physical activity, it is certainly a matter of concern for the sport sector. It is recommended that sport policy places a higher priority on grass-roots participation and that sporting organisations are supported to prioritise the retention issues occurring during adolescence, particularly for females so as to maximise the potential for sport to maintain its positive contribution to population wellbeing.

Changes in sport and physical activity participation for adolescent females: a longitudinal study

BACKGROUND

Participation in sport and physical activity is reported to decline during adolescence, particularly for females. However we do not have a clear understanding of changes in the context (i.e., modes and settings) of participation throughout adolescence. This study investigated longitudinal changes in physical activity participation and the specific modes and settings of physical activity, together with cross-sectional comparisons, for two age cohorts of female adolescents.

METHODS

Survey of 729 adolescent girls (489 recruited in Year 7 and 243 in Year 11). Participation in eight different modes/settings was reported. PA was measured using 24-h recall diary and metabolic equivalent weighted energy expenditure (MET-min) in Leisure Time Moderate and Vigorous Physical Activity (LTMVPA) on the previous day was calculated.

RESULTS

There were no significant changes in duration or total MET-min of LTMVPA on previous day. However, there were significant changes in the modes/settings of participation across time. Participation in school physical education rose during early adolescence before decreasing significantly, and participation in competitive sport and club sport significantly decreased over time; however there were increases in non-competitive forms of physical activity.

CONCLUSIONS

Overall levels of physical activity did not significantly decrease over adolescence, which is positive for physical health. However, the transition from structured sport to non-organised physical activity may effect social and psychological health, which needs to be further examined.

The contribution of sport participation to overall health enhancing physical activity levels in Australia: a population-based study

Background

The contribution of sport to overall health-enhancing leisure-time physical activity (HELPA) in adults is not well understood. The aim was to examine this in a national sample of Australians aged 15+ years, and to extend this examination to other ostensibly sport-associated activities.

Methods

The 2010 Exercise, Recreation and Sport Survey (ERASS) was conducted by telephone interview in four quarterly waves. Data from this survey were analysed to categorise leisure-time physical activity (LTPA) as HELPA or non-HELPA, and to categorise HELPA activities and sessions of HELPA activity by setting and frequency. The contribution of sport to HELPA was estimated, both directly through activities and settings classified as sport per se, and indirectly through other fitness activities ostensibly related to preparation for sport and enhancement of sport performance.

Results

Of 21,602 respondents, 82 % reported some LTPA in the 12 months prior to the survey. In aggregate, respondents reported 37,020 activity types in the previous 12 months, of which 94 % were HELPA. Of HELPA activities, 71 % were non-organised, 11 % were organised but not sport club-based, and 18 % were sport club-based. Of all sport activities, 52 % were HELPA. Of sport HELPA, 33 % was sport club-based and 78 % was undertaken ≥12 times/year. Sport club members were significantly more likely to have participated in running, but significantly less likely to have participated in walking or aerobics/fitness training, than non-club members.

Conclusions

Club sport participation contributes considerably to LTPA at health enhancing levels. Health promotion policies, and more specifically physical activity policies, should emphasize the role of sport in enhancing health. Sport policy should recognise the health-promoting role of community-based sport in addition to the current predominant focus on elite pathways.

Participation in modified sports programs: a longitudinal study of children's transition to club sport competition

BACKGROUND

Many children are not physically active enough for a health benefit. One avenue of physical activity is modified sport programs, designed as an introduction to sport for young children. This longitudinal study identified trends in participation among children aged 4-12 years. Outcomes included continuation in the modified sports program, withdrawal from the program or transition to club sport competition.

METHODS

De-identified data on participant membership registrations in three popular sports in the Australian state of Victoria were obtained from each sport's state governing body over a 4-year period (2009-2012 for Sport A and 2010-2013 for Sports B and C). From the membership registrations, those who were enrolled in a modified sports program in the first year were tracked over the subsequent three years and classified as one of: transition (member transitioned from a modified sport program to a club competition); continue (member continued participation in a modified sport program; or withdraw (member discontinued a modified program and did not transition to club competition).

RESULTS

Many modified sports participants were very young, especially males aged 4-6 years. More children withdrew from their modified sport program rather than transitioning. There were age differences between when boys and girls started, withdrew and transitioned from the modified sports programs.

CONCLUSIONS

If we can retain children in sport it is likely to be beneficial for their health. This study highlights considerations for the development and implementation of sport policies and programming to ensure lifelong participation is encouraged for both males and females.

Participation in sport and physical activity: associations with socio-economic status and geographical remoteness

Background

Many factors influence participation in sport and Physical Activity (PA). It is well established that socio-economic status (SES) is a critical factor. There is also growing evidence that there are differences in participation patterns according to residential location. However, little is known more specifically about the relationship of PA participation and frequency of participation in particular contexts, to SES and residential location. This study investigated the relationship of participation, and frequency and context of participation, to SES and location.

Methods

Three aspects of participation were investigated from data collected in the Exercise, Recreation and Sport Survey (ERASS) 2010 of persons aged 15+ years: any participation (yes, no), regular participation (<12 times per year, ≥12 times per year) and level of organisation of participation setting (non-organised, organised non-club setting, club setting).

Results

The rates of both any and regular PA participation increased as SES increased and decreased as remoteness increased. However, participation in PA was SES- or remoteness-prohibitive for only a few types of PA. As remoteness increased and SES decreased, participation in many team sports actually increased. For both SES and remoteness, there were more significant associations with overall participation, than with regular participation or participation in more organised contexts.

Conclusions

This study demonstrates the complexity of the associations between SES and location across different contexts of participation. Nevertheless, it seems that once initial engagement in PA is established, SES and remoteness are not critical determinants of the depth of engagement.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1796-0) contains supplementary material, which is available to authorized users.

Genome-wide sperm DNA methylation changes after 3 months of exercise training in humans

AIM

DNA methylation programs gene expression and is involved in numerous biological processes. Accumulating evidence supports transgenerational inheritance of DNA methylation changes in mammals via germ cells. Our aim was to determine the effect of exercise on sperm DNA methylation.

MATERIALS & METHODS

Twenty-four men were recruited and assigned to an exercise intervention or control group. Clinical parameters were measured and sperm samples were donated by subjects before and after the 3-month time-period. Mature sperm global and genome-wide DNA methylation was assessed using an ELISA assay and the 450K BeadChip (Illumina).

RESULTS

Global and genome-wide sperm DNA methylation was altered after 3 months of exercise training. DNA methylation changes occurred in genes related to numerous diseases such as schizophrenia and Parkinson's disease.

CONCLUSIONS

Our study provides the first evidence showing exercise training reprograms the sperm methylome. Whether these DNA methylation changes are inherited to future generations warrants attention.

Different methods of training load quantification and their relationship to injury and illness in elite Australian football

OBJECTIVES

To compare different methods of training load (TL) quantification and their relationship to injury and illness in elite Australian footballers.

DESIGN

Prospective cohort study.

METHODS

Forty-five elite Australian footballers (mean±standard deviation: age=23.4±3.8 years) from one elite club participated in this 15 week pre-season study. TL was quantified every session for each individual using four different methods involving rating of perceived exertion (RPE). Two of these methods enabled the quantification of TL for all exercise modalities whilst two were applicable only to outdoor field activities. One- and two-weekly cumulative TL was investigated against injury and illness data using a logistic regression model where the low TL group was considered as the reference group.

RESULTS

A general trend existed across all TL methods which suggested lower odds of injury and illness in high TL groups. The one-week RPE (all) and one-week RPExDuration (all) methods detected reduced odds of injury in high TL groups compared to low TL groups (p<0.05, OR=0.199-0.202). Similarly, the one-week RPE (field) method identified lower illness odds in the high TL groups (p<0.05, OR=0.083-0.182).

CONCLUSIONS

Higher TL appeared to provide a protective effect against both injury and illness. The inclusion of duration in the quantification of TL via RPE did not improve the ability of RPE to predict change in odds of injury or illness.

Linking secondary school physical education with community sport and recreation for girls: a process evaluation

BACKGROUND

The purpose of this study was to undertake a process evaluation to examine the reach, adoption and implementation of a school-community linked physical activity (PA) program for girls aged 12 - 15 years (School Years 7 - 9) using the RE-AIM framework.

METHODS

Various approaches were used to assess 'reach', 'adoption' and implementation: (a) a school environment survey of intervention schools (n = 6); (b) teacher feedback regarding the professional development component (91.1% response rate) and lesson implementation (60.8% response rate); and (c) post-intervention focus group interviews with physical education (PE) teachers (n = 29), students (n = 125), coaches (n = 13) and instructors (n = 8) regarding program experiences.

RESULTS

Reach and Adoption: Seven schools (n = 1491 Year 7-9 female student enrolment; 70% adoption rate), five tennis clubs, eight football clubs and five leisure centres participated in the program during 2011.

IMPLEMENTATION

Program design and professional development opportunities (training, resource manual and opportunities to work with coaches and instructors during PE classes) supported implementation and student engagement in PA. However, there was a lack of individual and organisational readiness to adopt program principles. For some deliverers there were deeply embedded ideologies that were not aligned with the Game Sense teaching approach upon which the program was based. Further, cognitive components of the program such as self-management were not widely adopted as other components of the program tended to be prioritised.

CONCLUSION

The program design and resources supported the success of the program, however, some aspects were not implemented as intended, which may have affected the likelihood of achieving further positive outcomes. Barriers to program implementation were identified and should be considered when designing school-community linked interventions. In particular, future programs should seek to assess and adjust for organizational readiness within the study design. For example, shared commitment and abilities of program deliverers to implement the program needs to be determined to support program implementation.

TRIAL REGISTRATION

ACTRN12614000446662. April 30th 2014.

Socioecological factors potentially associated with participation in physical activity and sport: A longitudinal study of adolescent girls

OBJECTIVES

Many adolescents are not physically active enough to receive associated health benefits. Furthermore, participation in physical activity generally declines during adolescence, and to a greater degree for females. Longitudinal research is required to better understand the determinants of change in physical activity by adolescent females to inform physical activity-related policy and practice. This study explored patterns of change in socioecological factors hypothesised to be associated with physical activity and sport, across the adolescent period for females.

METHODS

This longitudinal study employed three annual surveys of females from metropolitan and non-metropolitan areas recruited in Year 7 (n = 328) and Year 11 (n = 112). Self-report measures included questions regarding general barriers to participation, as well as factors relating to the socioecological domains.

RESULTS

The barriers where significant changes within or differences between cohorts were observed were mostly intrapersonal (lack of energy, lack of time due to other leisure activities). Lack of time was more prevalent in the Year 11 cohort than in the Year 7 cohort. Perceived importance of life priorities mainly related to education and study and more so for the Year 11 cohort. Perceived competence declined for the Year 7 cohort. Support from family and peers trended downwards in both cohorts, whereas access to facilities increased both within and between cohorts.

CONCLUSIONS

Significant patterns of change in the determinants of physical activity participation were observed across the adolescent period. It is important to consider flexible structure and scheduling of physical activity and strategies to develop competency in childhood and early adolescence.

Effectiveness of a school-community linked program on physical activity levels and health-related quality of life for adolescent girls

BACKGROUND

This study evaluated the effectiveness of a school-community program on Health-Related Quality of Life (HRQoL; the primary outcome), physical activity (PA), and potential mediators of PA among adolescent girls living in low-socioeconomic rural/regional settings.

METHOD

The study was a cluster-randomized controlled trial. Twelve communities with the requisite sports clubs and facilities were paired according to relevant criteria; one of each pair was randomly assigned to the intervention or control condition. Eight schools per condition were randomly selected from these communities and the intervention was conducted over one school year (2011). Female students in grades 7-9 in intervention schools participated in two 6-session PA units - a sport unit (football or tennis) and a recreational unit (leisure centre-based). These were incorporated into physical education (PE) curriculum and linked to PA opportunities for participation outside school. Students were surveyed at baseline and endpoint, self-reporting impact on primary and secondary outcome measures (HRQoL, PA) and PA mediators (e.g. self-efficacy). Linear mixed models for two-group (intervention, control) and three-group (completers, non-completers, control) analyses were conducted with baseline value, age and BMI as covariates, group as a fixed effect and school as random cluster effect.

RESULTS

Participants completing baseline and endpoint measures included: 358 intervention (baseline response rate 33.7%, retention rate 61.3%) and 256 control (14.1% and 84.0%). Adjustment for age and BMI made no substantive difference to outcomes, and there were no cluster effects. For HRQoL, after adjustment for baseline scores, the intervention group showed significantly higher scores on all three PedsQL scores (physical functioning: M ± SE = 83.9 ± 0.7, p = .005; psychosocial: 79.9 ± 0.8, p = .001; total score: 81.3 ± 0.7, p = .001) than the control group (80.9 ± 0.8; 76.1 ± 0.9 and 77.8 ± 0.8). The three-group analysis found intervention non-completers had significantly higher PedsQL scores (84.0 ± 0.8, p = .021; 80.4 ± 0.9, p = .003; 81.7 ± 0.8, p = .002;) than controls (80.9 ± 0.8, 76.1 ± 0.9 and 77.8 ± 0.8). There were no significant differences for any PA measure. Intervention completers had significantly higher scores than non-completers and controls for some mediator variables (e.g. self-efficacy, behavioural control).

CONCLUSION

Positive outcomes were achieved from a modest school-community linked intervention. The school component contributed to maintaining HRQoL; students who completed the community component derived a range of intra-personal and inter-personal benefits.

TRIAL REGISTRATION

ACTRN12614000446662. April 30th 2014.

A systematic review of the psychological and social benefits of participation in sport for adults: informing development of a conceptual model of health through sport

Background

The definition of health incorporates the physical, social and mental domains, however the Physical Activity (PA) guidelines do not address social health. Furthermore, there is insufficient evidence about the levels or types of PA associated specifically with psychological health. This paper first presents the results of a systematic review of the psychological and social health benefits of participation in sport by adults. Secondly, the information arising from the systematic review has been used to develop a conceptual model of Health through Sport.

Methods

A systematic review of 14 electronic databases was conducted in June 2012, and studies published since 1990 were considered for inclusion. Studies that addressed mental and/or social health benefits from participation in sport were included.

Results

A total of 3668 publications were initially identified, of which 11 met the selection criteria. There were many different psychological and social health benefits reported, with the most commonly being wellbeing and reduced distress and stress. Sport may be associated with improved psychosocial health in addition to improvements attributable to participation in PA. Specifically, club-based or team-based sport seems to be associated with improved health outcomes compared to individual activities, due to the social nature of the participation. Notwithstanding this, individuals who prefer to participate in sport by themselves can still derive mental health benefits which can enhance the development of true-self-awareness and personal growth which is essential for social health. A conceptual model, Health through Sport, is proposed. The model depicts the relationship between psychological, psychosocial and social health domains, and their positive associations with sport participation, as reported in the literature. However, it is acknowledged that the capacity to determine the existence and direction of causal links between participation and health is limited by the cross-sectional nature of studies to date.

Conclusion

It is recommended that participation in sport is advocated as a form of leisure-time PA for adults which can produce a range of health benefits. It is also recommended that the causal link between participation in sport and psycho-social health be further investigated and the conceptual model of Health through Sport tested.

A systematic review of the psychological and social benefits of participation in sport for children and adolescents: informing development of a conceptual model of health through sport

BACKGROUND

There are specific guidelines regarding the level of physical activity (PA) required to provide health benefits. However, the research underpinning these PA guidelines does not address the element of social health. Furthermore, there is insufficient evidence about the levels or types of PA associated specifically with psychological health. This paper first presents the results of a systematic review of the psychological and social health benefits of participation in sport by children and adolescents. Secondly, the information arising from the systematic review has been used to develop a conceptual model.

METHODS

A systematic review of 14 electronic databases was conducted in June 2012, and studies published since 1990 were considered for inclusion. Studies that addressed mental and/or social health benefits from participation in sport were included.

RESULTS

A total of 3668 publications were initially identified, of which 30 met the selection criteria. There were many different psychological and social health benefits reported, with the most commonly being improved self-esteem, social interaction followed by fewer depressive symptoms. Sport may be associated with improved psychosocial health above and beyond improvements attributable to participation in PA. Specifically, team sport seems to be associated with improved health outcomes compared to individual activities, due to the social nature of the participation. A conceptual model, Health through Sport, is proposed. The model depicts the relationship between psychological, psychosocial and social health domains, and their positive associations with sport participation, as reported in the literature. However, it is acknowledged that the capacity to determine the existence and direction of causal links between participation and health is limited by the fact that the majority of studies identified (n=21) were cross-sectional.

CONCLUSION

It is recommended that community sport participation is advocated as a form of leisure time PA for children and adolescents, in an effort to not only improve physical health in relation to such matters as the obesity crisis, but also to enhance psychological and social health outcomes. It is also recommended that the causal link between participation in sport and psychosocial health be further investigated and the conceptual model of Health through Sport tested.

Longer leukocyte telomeres are associated with ultra-endurance exercise independent of cardiovascular risk factors

Telomere length is recognized as a marker of biological age, and shorter mean leukocyte telomere length is associated with increased risk of cardiovascular disease. It is unclear whether repeated exposure to ultra-endurance aerobic exercise is beneficial or detrimental in the long-term and whether it attenuates biological aging. We quantified 67 ultra-marathon runners’ and 56 apparently healthy males’ leukocyte telomere length (T/S ratio) using real-time quantitative PCR. The ultra-marathon runners had 11% longer telomeres (T/S ratio) than controls (ultra-marathon runners: T/S ratio = 3.5±0.68, controls: T/S ratio = 3.1±0.41; β = 0.40, SE = 0.10, P = 1.4×10⁻⁴) in age-adjusted analysis. The difference remained statistically significant after adjustment for cardiovascular risk factors (P = 2.2×10⁻⁴). The magnitude of this association translates into 16.2±0.26 years difference in biological age and approximately 324–648bp difference in leukocyte telomere length between ultra-marathon runners and healthy controls. Neither traditional cardiovascular risk factors nor markers of inflammation/adhesion molecules explained the difference in leukocyte telomere length between ultra-marathon runners and controls. Taken together these data suggest that regular engagement in ultra-endurance aerobic exercise attenuates cellular aging.

Understanding the contexts of adolescent female participation in sport and physical activity

PURPOSE

Participation in physical activity (PA) is reported to decline in adolescence, particularly for girls. However, we do not know if this decline in PA is consistent across modes and settings or whether there are transfers of participation between modes and settings. Nor do we understand the changes in specific types of PA or the interaction between types of participation and different modes/settings. This study investigated contexts of PA participation for female adolescents at two life transition points.

METHOD

A survey of 489 Year 7 and 243 Year 11 adolescent girls was conducted, incorporating a measure of overall PA level and participation rates in seven modes/settings and in specific types of sport and PA.

RESULTS

Less than half of the respondents met or exceeded the recommended level of moderate or vigorous PA--60 min or more--on the previous day, and there was no statistically significant difference in the proportions in Years 7 and 11 (39.5% vs. 45.9%; p > .05). However, older adolescents shifted their participation away from organized, competitive modes and settings toward nonorganized and noncompetitive modes and settings and individual types of PA.

CONCLUSIONS

An understanding of the changes in PA modes and settings identified here can inform the planning of policies and implementation of programs for the promotion of PA by adolescent girls.

Family support and ease of access link socio-economic status and sports club membership in adolescent girls: a mediation study

BACKGROUND

Much research has been conducted into the determinants of physical activity (PA) participation among adolescent girls. However, the more specific question of what are the determinants of particular forms of PA participation, such as the link between participation through a sports club, has not been investigated. Accordingly, the aim of this study was to investigate the relationships between participation in a sports club and socio-economic status (SES), access to facilities, and family and peer support, for female adolescents.

METHODS

A survey of 732 female adolescent school students (521 metropolitan, 211 non-metropolitan; 489 Year 7, 243 Year 11) was conducted. The survey included demographic information (living arrangements, ethnicity indicators, and indicators of SES such as parental education and employment status and locality); access to facilities; and family and peer support (travel, encouragement, watching, praise, joint participation). For each characteristic, sports club participants and non-participants were compared using chi-square tests. Multiple mediation analyses were used to investigate the role of access, family and peer support in the link between SES and sport participation.

RESULTS

There were significant associations (p<0.05) between sports club participation and: all demographic characteristics; all measures of family and peer support; and access to sport-related facilities. Highest levels of participation were associated with monolingual Australian-born families, with two parents, at least one of whom was well-educated, with both parents employed, and high levels of parental assistance, engagement and support. Participation in club sport among both younger and older adolescent girls was significantly positively associated with the SES of both their neighbourhoods and their households, particularly in metropolitan areas. These associations were most strongly mediated by family support and by access to facilities.

CONCLUSIONS

To facilitate and promote greater participation in club sport among adolescent girls from low SES neighbourhoods and households, strategies should target modifiable determinants such as facility access and parental support. This will involve improving access to sports facilities and promoting, encouraging and assisting parents to provide support for their daughters' participation in sport clubs.

A comparison of rat SPECT images obtained using (99m)Tc derived from 99Mo produced by an electron accelerator with that from a reactor

Recent shortages of molybdenum-99 ((99)Mo) have led to an examination of alternate production methods that could contribute to a more robust supply. An electron accelerator and the photoneutron reaction were used to produce (99)Mo from which technetium-99m ((99m)Tc) is extracted. SPECT images of rat anatomy obtained using the accelerator-produced (99m)Tc with those obtained using (99m)Tc from a commercial generator were compared. Disks of (100)Mo were irradiated with x-rays produced by a 35 MeV electron beam to generate about 1110 MBq (30 mCi) of (99)Mo per disk. After target dissolution, a NorthStar ARSII unit was used to separate the (99m)Tc, which was subsequently used to tag pharmaceuticals suitable for cardiac and bone imaging. SPECT images were acquired for three rats and compared to images for the same three rats obtained using (99m)Tc from a standard reactor (99)Mo generator. The efficiency of (99)Mo-(99m)Tc separation was typically greater than 90%. This study demonstrated the delivery of (99m)Tc from the end of beam to the end user of approximately 30 h. Images obtained using the heart and bone scanning agents using reactor and linac-produced (99m)Tc were comparable. High-power electron accelerators are an attractive option for producing (99)Mo on a national scale.

Self-presentation origins of choking: evidence from separate pressure manipulations

Whether self-presentation is involved in the choking process remains unknown. The purpose of the current study was to determine the role of self-presentation concerns on the frequency of choking within the context of a recently proposed self-presentation model. Experienced field hockey players (N = 45) were randomly assigned to one of five groups (i.e., performance-contingent monetary incentive, video camera placebo, video camera self-presentation, audience, or combined pressure), before taking penalty strokes in low- and high-pressure phases. Results indicated that groups exposed to self-presentation manipulations experienced choking, whereas those receiving motivational pressure treatments decreased anxiety and increased performance under pressure. Furthermore, cognitive state anxiety mediated the relationship between the self-presentation group and performance. These findings provide quantitative support for the proposed self-presentation model of choking, while also holding implications for anxiety manipulations in future sport psychology research.

Does sports club participation contribute to health-related quality of life?

Given the social nature of participation in sport, we hypothesized that club sports participants would have greater well-being and quality of life than participants in other forms of physical activity (PA).

PURPOSE

The purpose of this study was to examine health-related quality of life and life satisfaction in women who participate in three contrasting forms of PA: club sport, gym activities, and walking.

METHODS

This was a cross-sectional study of the relationship between type of PA setting and measures of health-related quality of life (Short-Form Health Survey [SF-36]) and life satisfaction in 818 women living in rural Victoria, Australia, in 2007. Data were also compared with those from a normative sample of 2345 women.

RESULTS

After adjustment for potential confounders (age, education, marital status, children aged <16 yr, perceived financial stress, and level of recreational PA), four of the eight SF-36 subscales, the SF-36 mental health component summary score, and life satisfaction were significantly higher in the club sport group than that in the other groups.

CONCLUSION

Although cross-sectional research cannot establish causal links, the results suggest that participation in club sport may enhance the health benefits of PA.

Transition in participation in sport and unstructured physical activity for rural living adolescent girls

Physical activity (PA) is important for lifelong health; however, participation is lower in rural compared with metropolitan areas and declines during adolescence, particularly for girls. It is likely that this decline is related to the number of life transitions that occur during adolescence. This qualitative study examined the views of active rural living girls regarding the factors affecting their sport and PA participation, using the socioecological model. Twenty-seven girls aged 16-17 from four schools participated in semi-structured focus group discussions. Content and thematic analysis was conducted from verbatim transcripts using NVivo. The girls enjoyed involvement in community club sport with friends and they reported living in communities where participation in sport was a major form of social interaction. However, the desire to succeed educationally was a critical factor affecting their participation in sport and PA and influenced their movement from structured club sport to more flexible, but socially isolated individual activities. It is recommended that future longitudinal research should track rural living adolescent females as they complete secondary school, in order to better understand the influence of educational priorities upon sport and PA participation and to identify practical strategies for both schools and community organizations to foster continuing participation throughout this crucial period of life transition.

Using a socioecological approach to examine participation in sport and physical activity among rural adolescent girls

Adolescence is a critical time for developing lifelong healthy behaviors, including active lifestyles. Participation in sport and physical activity, however, declines during adolescence, and few studies have comprehensively identified why, particularly among rural girls. This article identifies a range of independent and interacting factors that influence sport and physical activity participation of rural adolescent girls. The socioecological model of health was used to guide four focus group discussions with Grade 7 girls (n = 34). The results showed that adolescent girls were positively influenced when sports or physical activities were fun, when they involved being with friends, and when they were supported by families and teachers through role modeling and positive feedback. A range of intrapersonal and organizational factors affected perceived self-competence, particularly the coeducational nature of school physical education classes and peer teasing, which supported social comparisons of skill level. In promoting sport and physical activity to rural adolescent girls, focus must be directed on developmentally appropriate activities that are fun, offering opportunities for single-sex classes, and generating cultural changes that encourage noncompetitive and self-referencing activities.

Effect of a nurse back injury prevention intervention on the rate of injury compensation claims

PROBLEM

This study evaluated the effect of introducing a No Lifting policy on back injuries to nurses, across an entire health care system.

METHODS

Methods included: analysis of the data for all public health agencies in the Australian state of Victoria; compensation data from the Victorian Workcover Authority; data about workforce and program implementation from a retrospective survey of agencies; longitudinal analysis of standardized workers compensation claim rates for back injuries before, during and after the intervention.

RESULTS

A statistically significant decline in back injury claim rates during implementation contrasted with no statistically significant trends within the periods before and after the intervention. A statistically significant reduction occurred in mean quarterly standard back injury claim incidence rates per 1,000 equivalent fulltime nursing staff (EFTNS), representing a 24% reduction in standard back injury claims/1000 EFTNS.

DISCUSSION

Ergonomics principles encourage changing the work environment to suit the worker. This approach delivered a significant improvement in the immediate term.

IMPACT OF INDUSTRY

The substantial decline in back injury rates signifies a major improvement in the safety of a critical aspect of the work environment for nurses.

Effect of a low-resource-intensive lifestyle modification program incorporating gymnasium-based and home-based resistance training on type 2 diabetes risk in Australian adults

OBJECTIVE

The purpose of this study was to assess the effectiveness of a low-resource-intensive lifestyle modification program incorporating resistance training and to compare a gymnasium-based with a home-based resistance training program on diabetes diagnosis status and risk.

RESEARCH DESIGN AND METHODS

A quasi-experimental two-group study was undertaken with 122 participants with diabetes risk factors; 36.9% had impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) at baseline. The intervention included a 6-week group self-management education program, a gymnasium-based or home-based 12-week resistance training program, and a 34-week maintenance program. Fasting plasma glucose (FPG) and 2-h plasma glucose, blood lipids, blood pressure, body composition, physical activity, and diet were assessed at baseline and week 52.

RESULTS

Mean 2-h plasma glucose and FPG fell by 0.34 mmol/l (95% CI -0.60 to -0.08) and 0.15 mmol/l (-0.23 to -0.07), respectively. The proportion of participants with IFG or IGT decreased from 36.9 to 23.0% (P = 0.006). Mean weight loss was 4.07 kg (-4.99 to -3.15). The only significant difference between resistance training groups was a greater reduction in systolic blood pressure for the gymnasium-based group (P = 0.008).

CONCLUSIONS

This intervention significantly improved diabetes diagnostic status and reduced diabetes risk to a degree comparable to that of other low-resource-intensive lifestyle modification programs and more intensive interventions applied to individuals with IGT. The effects of home-based and gymnasium-based resistance training did not differ significantly.

The effects of interval–exercise duration and intensity on oxygen consumption during treadmill running

The magnitude of improvement in peak oxygen uptake (V(o)(2peak))) and performance to an exercise training regime is related to the V(o)(2) of prior accumulated exercise training bouts. However, it is unclear whether constant rate training (CRT) or interval training (INT) preferentially alters the V(o)(2) of running exercise. Therefore, the purpose of this study was to compare the acute V(o)(2) response to constant, and interval training sessions. Consequently, this study compared the mean average V(o)(2) of 17 moderately trained participants to a 20-min CRT and two different 20min INT treadmill runs. Participants completed three treatments (twice) in random order over 3 weeks. In 1min INT participants completed 10x1min efforts at the velocity corresponding to V(o)(2peak) (V(peak)) interspersed with 10x1min efforts at 0.5V(peak). In the 2min INT, participants completed 5x2min efforts at the V(peak) interspersed with 5x2min efforts at 0.5 at V(peak). In CRT participants ran at a velocity equivalent to the mean velocity of INT (75% V(peak)). Mean average V(o)(2) for 2min INT, 1min INT and CRT were, respectively, 3200+/-661; 3076+/-6041; 2909+/-584mlmin(-1). Both INT sessions resulted in a significantly higher mean average V(o)(2) than CRT. Furthermore, 2min INT resulted in 90% of V(o)(2peak) being exceeded more frequently than 1min INT. We conclude that INT serves as a more potent stimulus for improvement in V(o)(2peak) and subsequent endurance performance than CRT.

Making sporting clubs healthy and welcoming environments: a strategy to increase participation

Sporting clubs are an ideal setting to promote community-wide participation in physical activity. Using the principles of the Ottawa Charter as a guide, this study explored the factors affecting the development of supportive environments as a mechanism to increase participation in club sport. The Victorian Health Promotion Foundation (VicHealth) funds State Sporting Associations (SSAs) to develop healthy and welcoming environments (HWE) in their associated clubs. The program focus areas are: welcoming and inclusive environments, sports injury prevention, 'smoke-free' environments, responsible serving of alcohol, sun protection and healthy eating. This paper sought to determine whether or not SSA Executive Officers (EOs) believe that the creation of a supportive environment will facilitate sporting club membership and to identify the factors that affect the development of the HWEs. Forty-two (82.4%) of the 51 funded SSAs completed a general survey and 36 (70.6%) of EOs responded to questions that were specifically addressed to them. EOs from six SSAs also participated in semi-structured interviews. SSA EOs (97.2%) believed that the creation of HWE in clubs would facilitate increases in participant membership. However, the data indicate incomplete development of the HWE focus areas at the club level because of limited club capacity and limited SSA support. Reportedly, the SSAs are at the stage of raising program awareness at the club level. It is suggested that SSAs should plan a structured approach to the development of HWEs that acknowledges the diverse capacity of their clubs, and garner the support of key club volunteers in order to establish HWEs.

Development of body oxygen stores in harbor seals: effects of age, mass, and body composition

Harbor seal pups are highly precocial and can swim and dive at birth. Such behavioral maturity suggests that they may be born with mature body oxygen stores or that stores develop quickly during the nursing period. To test this hypothesis, we compared the blood and muscle oxygen stores of harbor seal pups, yearlings, and adults. We found that pups had smaller oxygen stores than adults (neonates 57%, weaned pups 75%, and yearlings 90% those of adults), largely because neonatal myoglobin concentrations were low (1.6+/-0.2 g% vs. 3.8+/-0.3 g% for adults) and changed little during the nursing period. In contrast, blood oxygen stores were relatively mature, with nursing pups having hematocrit (55%+/-0.2%), hemoglobin (21.7+/-0.4 g%), and blood volume (12.3+/-0.5 mL/kg) only slightly lower than the corresponding values for adults (57%+/-0.2%, 23.8+/-0.3 g %, and 15.0+/-0.5 mL/kg). Because neonatal pups had relatively high metabolic rates (11.0 mL O2/kg min), their calculated aerobic dive limit was less than 50% that of adults. These results suggest that harbor seals' early aquatic activity is primarily supported by rapid development of blood, with immature muscle oxygen stores and elevated use rates limiting aerobic diving ability.

Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California

An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia.

An analysis of the forces required to drag sheep over various surfaces

Some occupational health and safety hazards associated with sheep shearing are related to shearing shed design. One aspect is the floor of the catching pen, from which sheep are caught and dragged to the shearing workstation. Floors can be constructed from various materials, and may be level or gently sloping. An experiment was conducted using eight experienced shearers as participants to measure the force exerted by a shearer when dragging a sheep. Results showed that significant changes in mean dragging force occurred with changes in both surface texture and slope. The mean dragging forces for different floor textures and slopes ranged from 359 N (36.6 kg) to 423N (43.2 kg), and were close to the maximum acceptable limits for pulling forces for the most capable of males. The best floor tested was a floor sloped at 1:10 constructed of timber battens oriented parallel to the path of the drag, which resulted in a mean dragging force 63.6N (15%) lower than the worst combination.

Immunohistochemical evidence for estrogen receptors in meibomian glands

PURPOSE

To look for sex hormone receptor distribution in three structures contributing to the normal human tear film: the conjunctiva, the accessory lacrimal glands, and the meibomian glands.

DESIGN

An immunohistochemical study. TISSUES AND CONTROLS: Forty-one upper eyelid specimens were collected from 15 male and 26 female patients (age range, 1.5-85 years) during blepharoptosis surgery via posterior tarsoconjunctival mullerectomy (Fasanella-Servat or Gavaris). In addition, control sections of histologically normal breast, prostate, and skin tissue were obtained.

METHODS

Immunohistochemical staining using mouse monoclonal antibodies against estrogen, progesterone, and androgen receptors was performed on all tissues and controls. Quantitation of the receptors was performed and expressed as percentage nuclear positivity. Specimens were divided into three groups based on the age of the patient: <12 years (n = 9); 18-55 years (n = 1); >55 years (n = 12).

RESULTS

Forty-one specimens contained conjunctiva. All were negative for estrogen, progesterone, and androgen receptors. Twenty-four specimens contained accessory lacrimal glands of Wolfring. All were negative for the three receptors. Twenty-two specimens contained meibomian glands. All were positive for estrogen receptors; one was positive for progesterone receptors and one for androgen receptors. Using Minitab statistical software (Minitab Inc. State College, PA), analysis of variation revealed no statistical difference between sexes or between age groups studied. The sebaceous glands of skin were uniformly positive for androgen receptors. Sebaceous glands of the face and scalp (3 of the 15 skin samples) were also positive for estrogen receptors.

CONCLUSIONS

Estrogen receptors are present in the meibomian glands of the upper eyelid. Unlike sebaceous glands elsewhere on the skin, the meibomian glands lack androgen receptors. Estrogen receptors may play a role in modulation of the lipid layer of the tear film, and their activity may be linked to meibomian gland dysfunction and dry eye syndrome.

Characterization of adrenergic receptors in the accessory lacrimal glands of the upper eyelid

PURPOSE

To identify the histologic location as well as the exact subtype of adrenergic receptors in the accessory lacrimal glands of the upper eyelid.

METHODS

Upper eyelid specimens were collected from 19 patients undergoing routine blepharoptosis correction via a posterior tarsoconjunctival mullerectomy. Immunohistochemical staining using polyclonal antibodies against human alpha 1, alpha 2, beta 1, and beta 2 receptors was performed on all specimens.

RESULTS

beta 1 receptors were the predominant adrenergic receptor subtype in the glands of Wolfring.

CONCLUSIONS

The presence of beta 1 receptors in the accessory lacrimal glands of the upper eyelid may suggest a possible role for selective beta 1 agonists in the treatment of keratitis sicca.

Distribution of adrenergic receptor subtypes in the retractor muscles of the upper eyelid

PURPOSE

To identify adrenergic receptor subtypes and their relative distribution in the retractor muscles of the upper eyelid, the levator palpebrae superioris, and the Müller muscle. The pattern of distribution of these receptors in the Müller muscle was further compared in patients with dysthyroid eyelid retraction and in normal subjects.

METHODS

Müller muscle specimens were collected from 19 patients undergoing ptosis correction and from 8 patients undergoing repair of dysthyroid eyelid retraction. Immunohistochemical staining for alpha 1-, alpha 2-, beta 1-, and beta 2-adrenergic receptors was performed using antihuman rabbit polyclonal antibodies.

RESULTS

alpha 2-Adrenergic receptors were the predominant subtype in the Müller muscle, and beta 1-adrenergic receptors were the predominant subtype in the levator muscle. There was no significant difference in the staining pattern between specimens collected from patients with dysthyroid eyelid retraction and those from normal subjects.

CONCLUSIONS

The interaction between the alpha 2 and beta 1 receptors in the upper eyelid retractor muscles may be important in the control of the upper eyelid position and may contribute to the development of dysthyroid eyelid retraction. Specific alpha 2 antagonists could be developed and may be effective pharmacologic agents for the treatment of eyelid retraction.

Sensitivity and specificity of the diagnosis of periocular lesions by oculoplastic surgeons

BACKGROUND

A few studies have assessed the sensitivity of ophthalmologists in diagnosing periocular lesions. However, no study has assessed their diagnostic specificity or the degree to which they overdiagnose various lesions. We performed a study to determine the sensitivity and specificity of oculoplastic surgeons' preoperative diagnoses of common and uncommon periocular lesions.

METHODS

Using the patient records of four oculoplastic ophthalmologists, we reviewed all charts documenting periocular surgery in which lesions were excised and sent for biopsy. For each of 358 cases we recorded the preoperative diagnosis as listed by the surgeon and the postoperative diagnosis as reported by the pathologist. Each preoperative diagnosis was then scored as correct or incorrect. The relative number of each type of lesion was determined, and the ophthalmologists' sensitivity and specificity were calculated.

RESULTS

The sensitivity and specificity for the eight most frequently lesions were (in order of frequency) basal cell carcinoma 92.1% and 81.6% respectively, papilloma 81.6% and 66.0%, cyst 66.7% and 69.7%, nevus 53.6% and 75.0%, seborrheic keratosis 27.8% and 71.4%, chalazion 93.3% and 100.0%, squamous cell carcinoma 33.3% and 55.6%, and xanthelasma 100.0% and 76.9%. The values for melanoma were 50.0% and 28.6%, for sebaceous gland carcinoma 0.0% and 100.0%, and for uncommon lesions (nonspecific inflammation, actinic keratosis, granuloma, cavernous hemangioma, folliculitis, benign sweat gland tumour, eccrine hidrocystoma and collagenous tissue) 27.8% and 57.1%. The overall accuracy in lesion identification was 70.0%.

INTERPRETATION

Although ophthalmologists have excellent diagnostic sensitivity and specificity for some types of lesion, such as basal cell carcinoma and chalazion, the identification of other lesion types, such as cyst, squamous cell carcinoma and possibly melanoma and sebaceous gland carcinoma, is less optimal.

Sclerosing sweat-duct carcinoma (malignant syringoma) of the upper eyelid: a patient report with immunohistochemical and ultrastructural analysis

Sclerosing sweat-duct carcinoma or malignant syringoma is a rare eyelid tumor. The authors report the first patient with sclerosing sweat-duct carcinoma involving the upper eyelid and present its immunohistochemical and ultrastructural features. The clinical features and the histopathologic and ultrastructural findings that distinguish this tumor from its benign counterparts are discussed. Sclerosing sweat-duct carcinomas are slow growing but locally invasive neoplasms that have a propensity to recur. Wide and deep surgical excision with frozen section evaluation of margins is recommended.

Transcanalicular removal of silastic nasolacrimal tubes

Removal of nasolacrimal tubes is often an awkward procedure when performed transnasally, especially in children and apprehensive adults. We evaluated in a prospective fashion the transcanalicular route to retrieve nasolacrimal tubes. Overall, this technique was well tolerated by patients and easy to perform. Tube breakage during removal may be a complication.

Blastogenesis and interleukin-2 receptor expression assays in the harbor seal (Phoca vitulina)

Two in vitro functional assays were developed to evaluate mitogen-induced responses of peripheral blood mononuclear leukocytes (PBML) from free-ranging harbor seals, Phoca vitulina. Lymphocyte proliferation was measured by a standard blastogenesis assay following optimization of culture conditions including mitogen concentration, cell density, and incubation time. These optimized parameters, with the exception of incubation time, were subsequently employed to measure lymphocyte activation by analytical flow cytometry using fluorochrome-based identification of cell surface interleukin-2 receptor (IL-2r) expression. Baseline values established for free-ranging harbor seals had extensive animal variability; there was evidence that the samples were derived from a group of animals with a normal distribution. Positive correlations were observed between blastogenesis assays, and between blastogenesis and activation assays, when using pokeweed or concanavalin A as the stimulus. However, no relationship was found in the expression of the IL-2r induced by these mitogens. This result supports the contention that the two mitogens stimulate different lymphocyte subpopulations. This was observed only with the IL-2r expression assay because of its unique ability to measure the number of T lymphocytes initially activated rather than the ultimate number of progeny cells identified by blastogenesis. Both assays, used concurrently, should provide a more comprehensive representation of lymphocyte competence and serve as a measure of animal health.