This study examined associations between organized sports participation, adiposity and key obesity-related behaviors, using a nationally-representative sample of Australian secondary students. Consistent with previous international research, males spent more time in organized sports than females [29, 30]. In contrast, no differences were observed across neighbourhood levels of SEP. This differs from national data showing that nonparticipation in organized sports is higher amongst families of a lower household level SEP . There may be key differences between neighbourhood and household level variables in predicting children’s obesity-related behaviours ; therefore, more research is needed in this area to make reliable conclusions regarding potential differences in weekly minutes of participation by levels of SEP. Those in rural and remote communities reported higher levels of participation than those in metropolitan locations. This is also in contrast to national data that reports higher participation rates among capital city dwellers . It is possible that rural and remote areas provide a safer environment in which to participate in sports  or be conducive to longer periods of participation than urban areas.
Those of Asian and Middle-Eastern backgrounds reported significantly fewer minutes spent in organized sports per week. This is consistent with national participation rates among younger adolescents whereby lower levels of participation are reported by adolescents of non-English speaking backgrounds . This is a promising avenue of future research given that organized sport has been used to promote health among non-English speaking Australians .
There were no differences in sports participation by weight status. This suggests that organized sports are a viable physical activity option for overweight and obese adolescents. There were, however, low levels of organized sports participation among underweight adolescents. This is consistent with previous Australian findings which demonstrate that underweight adolescents expend less energy through daily sports participation than their healthy-weight peers . This may be due to low levels of muscle mass and subsequently decreased opportunities for success in competitive sports. Therefore, underweight adolescents may elect not to participate in organised sports.
Higher rates of sports participation were associated with an increased likelihood of complying with national physical activity guidelines. This is consistent with a large body of previous literature that demonstrates a positive association between participation in sports and levels of physical activity , and affirms national and international policies to promote organized sports to combat the burden of physical inactivity [5–7]. Higher levels of sports participation were also associated with an increased likelihood of complying with electronic screen time guidelines. This is an important finding given the dearth of research in this area. Sirard et al.  have also reported that participation in team sports had a negative dose–response relationship with television viewing amongst U.S. adolescents. It may be that participation in organized sports takes place at times when opportunities for screen-based behaviors are also high, such as in the after-school hours. This is an interesting avenue of research because physical activity and screen-based behaviors are independent behaviors that do not necessarily correlate in adolescents . While more research is needed to investigate whether increasing sports participation can play a causal role in reducing harmful sedentary behaviours such as television viewing, these findings suggest that policies to combat physical inactivity through the promotion of organized sports in Australia may be justifiably extended to the public health goals of reducing sedentary behaviors.
We found that those who participated in >210 minutes of organized sports per week were more likely to meet national fruit and vegetable consumption guidelines, with a greater likelihood associated with higher quintiles of participation. This is consistent with a recent systematic review ; however, in contrast to this review we found no association between sports participation and the likelihood to frequently consume sugar-sweetened beverages or high-fat foods in our adjusted models. Unadjusted means (Table 1) showed that those who regularly consumed high-fat foods and SSB had significantly higher levels of sports participation than those who were irregular consumers. However, these differences were no longer significant when the models were adjusted for covariates. This is a particularly interesting finding. Given the typical clustering of health-related behaviors such as physical activity and healthy dietary behaviors  it could be expected that organized sports participation would be associated with both increased fruit and vegetable consumption and decreased consumption of high-fat foods and sugar-sweetened beverages. The lack of association with unhealthy dietary behaviors may be due to several factors. Despite the relatively small contribution of sports food outlets to overall calorie intake, the provision and promotion of unhealthy food choices at sports events is extremely common, and sends contradictory messages regarding acceptable food choices which lead to unhealthy dietary behaviors . Alternatively, the consumption of high-fat foods and sugar-sweetened beverages may be so pervasive in the population that measures of organized sports participation are unable to differentiate between those who do and do not consume these unhealthy options on a regular basis.
We found that sports participation was not associated with weight status, but was associated with waist circumference. However, this positive association was very small, and was potentially due to low levels of organized sports participation among underweight adolescents, or the finding that regular consumers of sugar-sweetened beverages and high fat foods participated in more organized sports than irregular consumers (in unadjusted analyses). Overall, however, it may be concluded that participation in organized sports has little relationship with weight status or adiposity, and this conclusion would be consistent with findings from a systematic review . There are two plausible explanations for this. Firstly, organized sports are not solely for individuals of a healthy weight. National studies conducted in the U.S. concluded that more than one in four organized sports participants are overweight or obese, while more than half of youth who are obese report participating in organized sports [38, 39]. Alternatively, because the value of sports to obesity prevention is primarily due to their contribution to total physical activity, low levels of physical activity during organized youth sports  may in part explain the lack of association with weight status.
This study provides representative data on duration of sports participation among Australian adolescents that is consistent with national estimates . The dataset also included a valid measure of participation in organized sport in minutes per week, without which the accurate estimation of the health benefits of sports at a population level would not be possible. Further, the sample size is sufficiently large to detect differences in behavioral risk factors according to the level of sports participation. The addition of measures of waist circumference and waist-to-height ratio to a measure of BMI adds strength to the conclusions regarding sports participation and weight status.
Limitations include the reliance on self-report measures of participation in physical activity, screen time and eating habits. In particular, concurrent self-reported participation in organized sports and physical activity are likely to be strongly related. Furthermore, SEP has been measured using participants’ postcode and not at an individual or familial level and may not accurately reflect their ability to afford organized sports or physical activity opportunities. The cross-sectional nature of the study limits assertions of causality. It may be that those adolescents who are more active and have healthier eating habits are more likely to participate in organized sports.