[Carlyn Waffa is a senior at The University of North Carolina at Chapel Hill. She is majoring in Exercise and Sport Science, and is a National Academy of Sports Medicine Certified Personal Trainer. She is currently an Athletic Development Intern at Athletic Lab.]
In the United States, childhood obesity affects roughly 12.7 million children and adolescents between the ages of two and nineteen years old, with the rate of obesity positively correlated with age (Ogden, 2015). Since 1980, the prevalence of obesity among children and adolescents has almost tripled (MDH, 2013). Recent research suggests that a child’s body composition by the time that they are just five years old is telling of what their body composition will be for the rest of their life. In one study, almost half of the children who were overweight in kindergarten grew into obese adolescents, and so on (Cunningham, 2014).
An alarming pattern of inactivity has consumed the nation – with daily participation in physical education classes declining across America (CDC, 2011). The negative effects of physical inactivity are numerous and include an increased chance of developing hypertension, heart disease, osteoporosis, colon and breast cancer, type II diabetes and obesity. What has become evident is that children need to be engaging in more physical activity in order to dodge the looming consequences of physical inactivity later in life.
In the 1970’s and 1980’s resistance training for adolescents was stigmatized because of a presumed high risk of injury. In 2017, this notion is erroneously cited, despite being obsolete. Typically, resistance training injuries occur due to poor training, excessive loading, poorly designed equipment, or free access to equipment. Nevertheless, these injury factors do not have any correlation with an athlete’s age, but instead, are confounding consequences of a lack of qualified supervision.
“Despite outdated concerns regarding the safety or effectiveness of youth resistance training, scientific evidence and clinical impressions indicate that youth resistance training has the potential to offer observable health and fitness value to children and adolescents, provided that appropriate training guidelines are followed and qualified instruction is available. In addition to performance-related benefits, the effects of resistance training on selected health-related measures including bone health, body composition, and sports injury reduction should be recognized by teachers, coaches, parents, and health care providers. These health benefits can be safely obtained by most children and adolescents when prescribed age-appropriate resistance training guidelines” (Faigenbaum, 2009).
Muscle and bone strengthening exercises should be performed by children and adolescents three or more times per week as part of their 60-minutes or more of physical activity, which they should engage in daily (ODPHP, 2008).
Compared to adults, children and adolescents have a lower capacity to generate adenosine triphosphate (ATP), which is the currency of energy at a molecular level within the body, by way of glycolysis. Instead, children have a greater reliance on fatty acid oxidation, which inhibits glycolytic pathways. Since children are smaller than adults, it is not surprising that they also have lower walking and running economies, as they have to take more strides to reach a given velocity. Thus, they have a greater demand for oxygen, and a higher relative oxygen uptake, than adult athletes during similar activities. A young athlete’s aerobic capacity to perform endurance tasks at a percent of their VO2 max, or the maximum rate at which an individual can utilize oxygen during maximal exercise, is comparable to that of an adult’s, however. Young athletes are also just as capable as adults of utilizing creatine phosphate and ATP to perform brief, intense bouts of activity. Notably, children and adolescents actually have a greater mitochondrial capacity for oxidative phosphorylation than adults, which means that they are superior at achieving steady-state oxygen uptake more quickly. With these physiological similarities and differences in mind, the same cardiorespiratory fitness prescription that may be prescribed to adults is advisable for training young athletes. That is, children and adolescents should engage in at least 60-minutes of aerobic exercise, daily, and the majority of their aerobic exercise should be performed at a moderate-to-vigorous intensity (ODPHP, 2008). Nonetheless, it is important to keep exercise fun and enjoyable for young athletes in order to foster future adherence to physical activity. The focus of exercise should be on the health-related benefits of aerobic activity. Exercise prescription for young athletes should include a variety of continuous activities, which ought to overlap into team or individual sports and recreational activities. In summary, however, bouts of aerobic exercise should add up to a minimum of an hour of activity, daily, and include at least ten minutes of intermittent, vigorous activity (Riebe, 2016).
The consequences of physical inactivity are morbid. Predictably, inactive children tend to grow into inactive adults. Overweight and obesity related conditions, which include heart disease, stroke, type II diabetes, certain types of cancer, and more, affect nearly 97 million Americans of all ages. In the United States, these conditions rank among the leading causes of preventable death (CDC, 2016). Moreover, the estimated annual medical cost of obesity in the United States is alarming. In 2008, this cost was calculated to be in the range of $147 billion, with the medical costs of obese patients costing on average $1,429 more than the medical costs of patients of normal weight (Finkelstein, 2009). Simply, America cannot afford to sugar-coat the obesity epidemic any longer, especially in regards to childhood obesity. It is time to take action against inaction.
CDC, “Adult Obesity Facts.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 01 Sept. 2016. Web. <https://www.cdc.gov/obesity/data/adult.html>.
CDC, “Physical Inactivity.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 22 Feb. 2011. Web. <https://www.cdc.gov/healthcommunication/toolstemplates/entertainmented/tips/physicalinactivity.html>.
Cunningham S A, Kramer M R, Narayan K M. Incidence of childhood obesity in the United States, The New England Journal of Medicine, 2014, vol. 370 (pg. 403-411)
Eric A. Finkelstein, Justin G. Trogdon, Joel W. Cohen and William Dietz Annual Medical Spending Attributable To Obesity: Payer-And Service-Specific Estimates Health Affairs 28, no.5 (2009): w822-w831 doi: 10.1377/hlthaff.28.5.w822 originally published online July 27, 2009
Faigenbaum et al. Youth Resistance Training: Updated Position Statement Paper From the National Strength and Conditioning Association, Journal of Strength & Conditioning Research, 2009, vol. 23 (pg. S60-S79) doi: 10.1519/JSC.0b013e31819df407
Minnesota Department of Health (2013). Office of Statewide Health Improvement Initiatives. Overweight and Obesity. Retrieved from http://www.health.state.mn.us/divs/hpcd/chp/cdrr/obesity/pdfdocs/obesityfactsheet.pdf
ODPHP, “Children and Adolescents.” Children and Adolescents – 2008 Physical Activity Guidelines. 2008. Web. <https://health.gov/paguidelines/guidelines/children.aspx>.
Ogden CL, Carroll MD, Fryar CD, Flegal KM. Prevalence of obesity among adults and youth: United States, 2011–2014. NCHS data brief, no 219. Hyattsville, MD: National Center for Health Statistics. 2015.
Riebe, Deborah, Jonathan K. Ehrman, Gary Liguori, and Meir Magal. ACSM’s Guidelines for Exercise Testing and Prescription. Ninth ed. Philadelphia, PA: Wolters Kluwer Health, 2016. Print.