Stability of television viewing and electronic game/computer use in a prospective cohort study of Australian children: relationship with body mass index

Background
While much cross-sectional data is available, there have been few longitudinal investigations of patterns of electronic media use in children. Further, the possibility of a bi-directional relationship between electronic media use and body mass index in children has not been considered. This study aimed to describe longitudinal patterns of television viewing and electronic game/computer use, and investigate relationships with body mass index (BMI).
Methods
This prospective cohort study was conducted in elementary schools in Victoria, Australia. 1278 children aged 5–10 years at baseline and 8–13 years at follow-up had their BMI calculated, from measured height and weight, and transformed to z-scores based on US 2000 growth data. Weight status (non-overweight, overweight and obese) was based on international BMI cut-off points. Weekly television viewing and electronic game/computer use were reported by parents, these were summed to generate total weekly screen time. Children were classified as meeting electronic media use guidelines if their total screen time was ≤14 hrs/wk.
Results
Electronic media use increased over the course of the study; 40% met guidelines at baseline but only 18% three years later. Television viewing and electronic game/computer use tracked moderately and total screen time was positively associated with adiposity cross-sectionally. While weaker relationships with adiposity were observed longitudinally, baseline z-BMI and weight status were positively associated with follow-up screen time and baseline screen time was positively associated with z-BMI and weight status at follow-up. Children who did not meet guidelines at baseline had significantly higher z-BMI and were more likely to be classified as overweight/obese at follow-up.

Conclusion
Electronic media use in Australian elementary school children is high, increases with age and tracks over time. There appears to be a bi-directional association suggesting that interventions targeting reductions in either screen time or adiposity may have a positive effect on both screen time and adiposity.

Player movement patterns in an elite junior Australian Rules Football team : an exploratory study

This study explored the physical movement patterns associated with an elite Under 18 Australian Football (AF) team. Five field positions were selected with observations recording the number and relative per cent of "working" efforts (jogging, running, and sprinting), "resting" efforts (walking) and the total distances associated with "working" or "resting" efforts. Intra-observer reliability, using test- retest method, showed correlations were r = 0.98 or greater. The Wing position covered 11,877 m, the greatest total distance during an entire game, whilst the HBF and Centre positions both recorded 11,545 m and 11,537 m respectively and the Ruck position covered 9,203 m. The HBF recorded the greatest frequency of 'working' and 'resting' efforts (180 and 182 respectively), whilst the Wing (166 and 158), Centre (162 and 149) and Ruck (161 and 166) showed similarities in their results. The Wing position recorded the longest average distance per 'working' effort (58 m) whilst the Centre position recorded the longest average distance per 'resting' effort (17 m). Results also show the completion of less total efforts and smaller total distances, in Under 18 players, recorded compared to professional senior AF data. The results from this study suggest that further in-depth research is required into movement patterns and game activity demands in this AF playing group.

Sport consumer behavior research: improving our game

Sport consumer behavior (SCB) research continues to grow in both popularity and sophistication. A guiding principle in much of this research has focused on the nature of sport-related experiences and the benefits sport consumers derive from these experiences. This emphasis has generated new knowledge and insights into the needs and wants of sport consumers. Although these efforts have contributed to the field's understanding of SCB, the vast majority of this research has centered on psychological phenomena and the evaluative and affective components of these sport experiences. Approaches to this work have also narrowed, with SCB research predominately relying on cross-sectional studies and attitudinal surveys to collect information. This has resulted in limited findings that seldom account for how various situational or environmental factors might influence attitudinal data patterns at the individual and group level. This special issues seeks to deepen our understanding of SCB by providing seven papers that demonstrate or validate findings using multiple studies or data collections.