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.
AMS
Edmonton, Alberta
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
Monday, November 14, 2011
Thanks for this summary of the recent paper, Dr. Sharma.
The idea that sport can solve obesity is ludicrous, but fits in nicely with the largely misconstrued role of physical activity in weight loss. Exercise is marketed as a weight loss tool, so in some ways I cannot blame the public for thinking that joining a gym (and of course going regularly) will solve one’s weight problems.
A lack of understanding about precisely how much or little energy is expended during youth sports or other activities together with an equal dearth of understanding around the energy density of convenience and other foods will help people continue to think sports and exercise have a profound effect on weight loss.
Anyone close to physical activity and obesity research, as well as any exercise scientist, will understand that being “active” is a way to help prevent weight gain and reap the health benefits of cardiovascular exercise. More studies like this one will help provide the evidence, but others must translate the findings and communicate them to clients, patients, members, etc.
Thanks again, I enjoy reading your posts.
Monday, November 14, 2011
Are the results explained by selection, instead of the putative efficacy of youth sports in reducing the probability of obesity? Remember that participation in sports is voluntary, and some people will not participate due the dejection not being able to contribute significantly to a competitive team. Perhaps the children that participate in youth sports are genetically advantaged, as they are able to resist obesity, although Dr. Sharma has some evidence against that supposition since he posted a hypothesis paper that proposed that “thrifty genes” makes one “efficient” athletically, but predisposes one to obesity if one is one exercising.
Monday, November 14, 2011
Thanks for bringing this research to our attention, Dr Sharma. I agree with ‘Sports Scientist’ that studies like this provide some evidence, but ultimately what we do with that information is the key.
What I take away from this is that the ‘culture’ change that faces us when it comes to the socialization around organized sports at all levels, needs to be addressed. Be it for children or adults, and encompassing the entire continuum from community to professional sports, more work needs to be done to shift to healthier choices in the food we eat and the energy we expend. Without throwing out the proverbial ‘baby with the bathwater’, let’s take the positive things around organized sports teams – the physical activity it does offer – and address the not-so positive things – fast food consumption, poor food choices due to time, drinks consumed, decreasing down time of sedentary times of sports, organizing parents and supporters around how they can be part of the change to eating better, being more active and living healthier while still enjoying sports, be it their children’s team or their favorite professional team.
We are seeing only the tip of the iceberg, but we must start somewhere and learn as we go, integrating and reflecting on research as we go.
Thanks for keeping us engaged.
Monday, November 14, 2011
As someone who has always been, at very least, chubby, I still carry the psychological scars of constantly being chosen last for the team and being forced to look like an idiot since I was pathetic at running hurdles, swinging over the pummel horse, running races, climbing ropes, playing baseball…you name it. I was pathetic at sports period. I never even managed to learn to skip double-dutch.
Like all children growing up in the 60s, I rode my bike or walked to school and generally kept active. In our home, we ate almost no sweets or processed foods. Nor was overeating a problem. We were just heavier than the norm.
Something’s got to give in the way we get children involved in physical activity. If phys ed is still taught the way it was when I was a child, countless children are continuing to be pushed to the margins and discouraged from engaging in physical activity.
Physical activity as a way to lose weight is, in most cases, not very effective. But physical activity to promote better health (regardless of one’s weight) is a laudable goal. Would that the schools could figure out how to do this without making the flat-footed nerds amongst us just want to hide in the closet.
Monday, November 14, 2011
Again, the question of whether youth sports prevent obesity (as in having an actual causative effect instead of fitting athletes merely participating in sports is interesting) is interesting, but I do not that even an affirmative answer has much relevance in the realm of public policy. Sports and track involves competition; competition involves losers; losers are disproportionately among the less fit (although I skinny, I was still bad at physical sports even when competing against other girls); losers are implicitly discouraged from participating. Even practicing is discouraging for me because I knew that no matter how hard I train, I could never run a mile in under six minutes. In order for one to exercise, one has to believe that there are some benefits that can be reaped, and the performance benefit does not manifest itself in low or non-responders.
*As for myself, I run a mile during a week, and walk about 6 miles twice per week. I think it clears my head.
“Physical activity as a way to lose weight is, in most cases, not very effective. But physical activity to promote better health (regardless of one’s weight) is a laudable goal. Would that the schools could figure out how to do this without making the flat-footed nerds amongst us just want to hide in the closet. ”
Exercise is not an efficient way of burning calories; it is just better to restrict calories instead. The thing about exercise is that there is no single overwhelming benefit to encourage it: exercise, instead, has an impressive calculus of benefits – it burns some calories, acts as an antidepressant, improves physical fitness, improves one’s lipid profile, lowers blood pressure, reduces resting heart rate, although the impact of exercise varies among individuals. The magnitude of one of these benefits alone may not be compelling to entice one to exercise and one may not reap some of the promised benefits due to natural variation, but it is the aggregate benefit of the numerous facets of exercise that makes it a somewhat attractive proposition.
Monday, November 14, 2011
Hi Dr. Sharma. I do believe it should be “Do Youth Sports Prevent Obesity”. Nonetheless, I wonder if you might comment on prepubertal fat accumulation- I’m not sure how to correctly describe this-which prepares the child for the pubertal growth spurt. I have often counselled parents to be aware of this blip in weight and not to be too focused on weight per se, but rather, to allow the child to ‘grow into’ his appropriate weight. The focus would be to eat healthily and not ‘worry’ too much about this temporary weight gain. Thanks for your comments in this regard. Penny.
Monday, November 14, 2011
Hi Dr. Sharma:
This issue is clearly a case of doing something is better then doing what appears to be nothing. Youths need physical activity to grow socially and emotionally the benefit of after school and community league activies is that the child is chosing to do so–not like P.E. as it was when I was in school. A non-athelet, non-geek I HATED sports actities at school.
The benefit of using a gym is that it gives an individual something tto do other then eat. This may be followed by having someone to socialize with afterwards over coffee discussing the issues of the day with–the industrial hearing lose music aside. The real issue is will childhood recreation prevent weight gain; with this in mind I recall a story that I read to my son about Wayne Gretzsky’s it involved his sister there had been a bout of freezing rain the day shortly before then she went outside to walk to a friends place icy sidewalks are mean places to fall which she did she went from active to inactive due to torn ligaments or tendents that were not treated properly and from figure skating daily to all day dieting with more weight then needed. I relate this account because there are some youth who can eat plenty of high calorie foods and still keep weight off however, an injury reduces mobility and reduced mobility.
While this is one account there are no shortage of persons who follow this pattern or not having time to keep up with sports and leaving it off but not changing there calorie intake accordingly. Thank you for high lighting this research
Tuesday, November 15, 2011
Dr. Sharma,
The rather obvious confounding factor here is obesity and pre-obesity to begin with, isn’t it? I mean my little girl loved sports. I dutifully took her to softball and soccor and basketball.
But at soccor she spent most of an hour standing still and that didn’t count that the 2x week practices happened more like 2x a month because the coach constantly canceled. At softball she spent most of an hour standing in the field, the rest sitting on a bench, with the sole focus being the 2 minutes at bat, so if that didn’t go well it was a horrible trauma. Basketball was a little better. All three sports had 2-x breaks during games or practice filled with juice packs and sugary carby foods. I didn’t know much about nutrition then so I was oblivious, but looking back I see the issue.
She dropped out of soccor and basketball when the combination of not sprinting well (the only activity tended to be sprinting) and not wanting to wear shorts in front of other people combined. I pulled her out of softball for other reasons that still amounted to, a bunch of standing around and/or eating junk with no visible reward for this.
So if you surveyed me at one point you would have seen that when she was fit she was in sports and when her bmi was clearly too high she was not.
Sports did not keep her thin, not that they should have to, but I’m sure you see my point.
Best,
PJ