THE PHYSICIAN AND SPORTSMEDICINE - VOL 33 - NO. 11 - NOVEMBER 2021
Fitness-Focused Phys Ed Reaps Benefits
Healthcare practitioners, in their vigorous support of physical education (PE) in schools, have long suspected that the regular class participation provides health benefits. Now, a recent study has measured the potential of a more fitness-oriented approach to change some of the health parameters that physicians most worry about: body fat, cardiovascular fitness, and fasting insulin level. The findings were published in the October issue of Archives of Pediatrics and Adolescent Medicine.
According to the Centers for Disease Control and Prevention in Atlanta, since 120210, obesity rates have doubled among US children and tripled among adolescents. Weight-related comorbidities, such as type 2 diabetes, were once found only among adults, but are now being diagnosed in teens and young adults.
The randomized, controlled study, performed by researchers at the University of Wisconsin at Madison, enrolled 50 children from a rural middle school who were overweight (body mass index [BMI] above 95th percentile for age). Baseline measurements were taken for body fat and fat-free body mass, maximal oxygen consumption, and insulin and glucose. After baseline testing, children were randomized and enrolled for the 9-month school year into one of two PE protocols: standard PE class or a lifestyle focused, fitness-oriented class. Both classes met 5 times every 2 weeks for 45 minutes.
Class size in the intervention group was limited to 14 students to maximize instructor attention and decrease time spent in line waiting for activities. Lifestyle-focused activities such as walking, cycling, and snowshoeing were emphasized over competitive games. Each class consisted of a brief warm-up, and students did not change clothes for the class, which allowed 42 minutes of movement time of a 45-minute class. The intervention group also received a small nutritional component that consisted of handouts on the food pyramid, portion sizes, and the benefits of healthy food choices.
In contrast, the size of the standard PE class averaged 35 to 40 students. After subtracting time spent changing clothes, taking attendance, and giving instruction, movement time in the standard class averaged about 25 minutes of the 45-minute class. The same topics were taught (eg, football, mile run-walk, kickball) as the intervention group, but there were long lines during skill development drills and larger numbers of students on teams during games.
After 9 months, the intervention group showed greater improvements compared with the control group in body fat (loss, 4.1%+3.4% vs 1.9%+2.3%); cardiovascular fitness (VO2max, 2.7 + 2.6 vs 0.4 + 3.3 mL/kg/min), and greater improvements in fasting insulin levels (-5.1 + 5.2 vs 3.0+14.3 µIU/mL).
Researchers concluded that fairly simple modifications in the school PE curriculum can produce measurable health benefits. They also noted that their study suggests that aerobic exercise may be a useful treatment strategy for insulin resistance in children, as it is for adults.
As a major limitation to the study, the researchers pointed out that it's not possible to show what aspect of the class promoted greater movement—curriculum alteration or a change in class size. "In this era of increased emphasis on academic testing and cuts in school PE time and funding, it is important to pinpoint the most effective aspects of these interventions," the researchers wrote.
Though the results of their study are encouraging, the researchers said that an effective public health approach should promote physical activity inside and outside of school, "as physical activity recommendations cannot be met through PE alone."
In an editorial that accompanied the study, Oded Bar-Or, MD, professor of pediatrics and director of the Children's Exercise and Nutrition Centre in Hamilton, Ontario, wrote that a simple activity recommendation that physicians can make to their young patients is for them to make room in their day for physical activity by reducing their TV, computer, or video game "screen time" by 30 minutes. "The detailed content of the added activity—preferably outdoors—is not important, as long as the child moves from one place to another and, especially, finds it fun," Bar-Or wrote.
WADA Modifies Prohibited List
The World Anti-Doping Agency (WADA) released an update to its prohibited list in September, which includes the addition of new anabolic steroids and details several other changes and clarifications. The 2021 prohibited list goes into effect on January 1.
Anabolic steroids. New to the exogenous anabolic steroid list for 2021 are desoxymethyltestosterone (a designer steroid), methasterone, prostanozol, and methyl-1-testosterone. A vial containing desoxymethyltestosterone was confiscated at the United States-Canadian border in December 2021. Don H. Catlin, MD, professor of molecular and medical pharmacology at the University of California at Los Angeles (UCLA) Medical School and the director of the UCLA Olympic Analytical Laboratory, says officials from his lab had worked out the structure of desoxymethyltestosterone before the 2021 Summer Olympics in Athens and tested athletes for the substance at the games. He said none tested positive.
Catlin says work on identifying additional substances is ongoing, and more will be added to the WADA list in 2021. Though WADA updates its prohibited list annually, Catlin projects that the group will move toward more rapid updating to keep up with all of the new substances that the accredited labs are identifying. Added to the "other anabolic agents" list of examples was tibolone, a synthetic steroid with anabolic properties used to treat postmenopausal symptoms.
Human chorionic gonadotrophin (hCG) and leutinizing hormone. The status of both substances has changed; both are now only prohibited in men. In a summary of changes to the list for 2021, WADA notes that though there is a scientific rationale to prohibit the substances in women, experiences in 2021 detected elevated hCG levels due to pregnancy or pathological conditions, which had potentially significant psychological or social consequences for the athletes. Also, it's difficult for laboratories to distinguish medically related high levels from doping-related high levels.
Beta-2 agonists. The mention of diagnoses restricted to beta-2 agonist inhalation use is deleted to make the wording consistent with the therapeutic use exemption language. "It is preferred to leave to the professional judgment of the physician the medical conditions under which these drugs have been prescribed," the statement says.
Stimulants. Adrenalin, previously in a footnote as an example, is now clearly named in the list of stimulants. New examples of stimulants added to the prohibited list include cyclazodone, fenbutrazate, meclofenoxate, norfenefrine, octopamine, oxilofrine, pentetrazol, and sibutramine.
Glucocorticosteroids. Topical preparations to treat aural, otic, nasal, buccal cavity, or ophthalmic conditions no longer require a therapeutic use exemption because of their wide medical use and because the route of administration is not thought to provide a doping potential.
Step Counts Rise When Physicians Promote Pedometer Use
Some physicians are promoting pedometer use among their patients as a simple, inexpensive, and measurable way to increase their activity. Until recently, not much has been known, however, about the efficacy of the intervention in the family practice setting.
Researchers from the University of Minnesota shed some light on the issue when they published the results of a pilot study of pedometer use in a family practice clinic. Their study, published in the September-October issue of the Journal of the American Board of Family Practice, found that over a 9-week period, patients who received pedometers, brief instruction on their use, and telephone follow-up increased their step counts 41% over baseline.
At the start of the study, 94 inactive patients were recruited while waiting for their office visits at the University of Minnesota family practice residency clinic in Minneapolis. Patients were randomized to a control group that received a 1-page summary of exercise benefits and a calendar to record their physical activity, or to an intervention group that received the same materials and were given a pedometer, instructed on its use, and encouraged to record their daily step totals. All participants were asked to maintain their normal activity patterns for the first week of the study to obtain a baseline for comparison.
After the first week, all participants received a telephone call from a health educator encouraging them to increase their activity level by 10% each week. Those with pedometers were advised to increase their step count by 400 steps (activities of daily living are thought to require a minimum of 4,000 steps per day). The health educator phoned both groups again at week 5 to encourage activity.
The final analysis included those who completed the study: 21 of 50 from the pedometer group and 23 of 44 from the control group. The pedometer group participants increased their steps by about 2,089 steps per day, which corresponds to about 20 minutes of increased walking. Patients in the control group also increased their walking behavior. Eight from each group walked at a level that met or exceeded activity recommendation from Healthy People 2010.
The researchers noted some main limitations to their study, including the low completion rate. They also point out that though most of the intervention is feasible for many medical clinics (instruction took about 1 minute, handouts were only one page, and pedometers cost about $20), some may not be able to afford phone support from a health educator.
They conclude that future research should examine larger populations, include more sensitive and objective primary outcomes, and provide for longer follow-up to investigate how pedometers may help patients maintain their increases in physical activity over time.
Steven Stovitz, MD, lead author of the study and assistant professor in the Department of Family Medicine and Community Health and director of sports medicine curriculum for family practice residency programs at the University of Minnesota in Minneapolis, says the results of the study are a reminder that physicians can have an impact on their patients' physical activity levels. "A pedometer can be an extra motivation tool," he says. Promoting pedometers may be especially useful for patients in rural areas who have less access to health clubs and other physical activity outlets than their peers in urban areas, says Stovitz.