Does Youth Sports Prevent Obesity?Monday, November 14, 2011
This question appears almost a ‘no-brainer’ and many readers will once again put the very fact that I touch on this topic down to ‘sports-bashing’ – but, the ‘uncomfortable truth’ for youth sports enthusiasts is that the answer to this question is far less clear than one would perhaps expect.
Given the rather mixed literature on whether or not (organized) youth sports can provide a solution to the obesity problem, Toben Nelson and colleagues from the University of Minnesota, Minneapolis, have taken a careful look at the published literature on this issue – their findings are published in the latest issue of Current Sports Medicine Reports.
While their review of 19 studies on this topic showed that kids participating in sports were indeed more physically active than kids who did not participate, overall they found no clear relationship between participation and weight status. While 12 studies did note some (albeit small) differences in body weight in selected subgroups (but not the entire study population in these studies), the other 7 studies found no differences in body weight at all.
Further analyses of these studies revealed some ‘surprising’ findings that may well explain these findings:
Firstly, there were substantial disparities between the overweight and obesity rates between sports: sports with a higher level of obesity included rugby, swimming, judo, and tennis, and sports with lower levels of obesity included gymnastics, handball, horse riding, and dance.
Thus, as the authors note:
“The lack of a clear difference in weight status between participants and nonparticipants observed in some of the studies reviewed may be attributed to the type of sport studied and the specific body type suited for that sport.”
Secondly, although kids participating in sports tend to have more activity than non-participating kids, the overall differences are not as large as one would assume. While in one study, on the days on which kids participated in sports added about 30 mins of moderate to vigorous physical activity to that day, another study that objectively assessed physical activity of youth sport participants in soccer, baseball, and softball, found that fewer than one in four met recommended levels of activity during their sport team practice.
“It is not clear from these studies how much of the sedentary time in sport was spent in these sport-related activities and it is also not clear what extent to which physical activity can be optimized in these settings without sacrificing instruction and skill development.”
Thirdly, it is very possible that participation in youth sports can negatively affect both the quality and quantity of food and drink consumed, potentially resulting in net positive energy balance.
Thus, although one study found that youth involved in sport had better overall nutrient intake than youth not involved in sport, several other studies showed that total caloric intake often exceeded actual expenditure. One study of middle and high school youth found a positive association between sports team participation and frequency of fast food consumption and that sport team participation during middle school predicted greater fast food consumption into the high school years. In other studies, sport participants were more likely than nonparticipants to consume sports drinks and fruit juice and were equally likely to consume soft drinks.
As the authors point out:
“Candy, confectionary, sugar-sweetened beverages (including sport drinks), and ice cream are commonly sold at youth sport events or brought to the event by contestants and parents. Youth sport marketing is a key part of food and beverage marketing strategies, and voluntary industry guidelines may actually encourage food and beverage companies to associate those products with health and fitness activities such as youth sport.”
“Among some sport teams and leagues, the practice of providing snacks and beverages is institutionalized, wherein volunteer parent coordinators develop and assign a snack schedule. The snacks and beverages provided are often packaged convenience food (e.g., sport drinks, soda pop, candy bars, cookies, chips, “fruit” snacks) and, in combination, could total 300 to 500 calories or more.”
This is certainly problematic as,
“Youth, parents and coaches may have little or no awareness of the large number of calories contained in snacks and beverages commonly offered in youth sport settings or the relatively small number of calories children expend during sport.”
The authors also discuss the observations that:
“In addition to direct access to excess calories available in sport settings, participants are subject to time pressures associated with attending sport practices and events. Time pressures may lead to more consumption of fast food and other processed food, which tend to be convenient but less healthy options. Regular family meals are associated with healthful dietary behaviors but may be sacrificed due to sport participation. Parents of youth sport participants report that sport-related time pressures influence meal planning and preparation, interfering with family meals.”
Another issue concerns the almost inevitable discontinuation of sporting activity, which may occur for numerous reasons including personal factors such as lack of enjoyment or motivation, time constraints, pressure to perform, and low achievement orientation and organizational factors such as coaching issues, lack of playing time, and lack of opportunities to participate.
“Regardless of the reason for dropping out of sport, decreasing energy expenditure without replacement with other forms of physical activity and/or decreasing caloric intake can promote energy surplus and weight gain. Childhood eating patterns help establish adult dietary habits, and these findings highlight the importance of promoting good nutrition in conjunction with youth sports.”
Overall, the authors conclude that:
“Given the limited available research, there is not sufficient evidence to conclude that sport participation protects against the development of obesity. Additional research is needed to understand weight status and weight gain among sport participants and to determine whether, and under what conditions, sport can effectively prevent unhealthy weight gain.”
At a minimum:
“Additional discussions among key stakeholders are needed, and interventions to reduce the exposure to the excessive calories and other unhealthy food and beverage options available in youth sport must occur before the promise of obesity prevention in youth sport can be realized.”
As I have discussed before, it appears that both the potential benefits and downsides of sports as a means to tackling obesity have more to do with the impact of sports (and sport settings) on caloric intake than expenditure.
Nelson TF, Stovitz SD, Thomas M, Lavoi NM, Bauer KW, & Neumark-Sztainer D (2011). Do youth sports prevent pediatric obesity? A systematic review and commentary. Current sports medicine reports, 10 (6), 360-70 PMID: 22071397