Longitudinal Association between Weight Status, Aerobic Capacity, Muscular Strength, and Endurance among New York City Youth, 2010-2017

Multilevel Interventions Targeting Obesity: State of the Science and Future Directions

A seminal report, released in 2001 by the Institute of Medicine, spurred research on the design, implementation, and evaluation of multilevel interventions targeting obesity and related behaviors. By addressing social and environmental factors that support positive health behavior change, interventions that include multiple levels of influence (e.g., individual, social, structural) aim to bolster effectiveness and, ultimately, public health impact. With more than 20 years of multilevel obesity intervention research to draw from, this review was informed by published reviews (n = 51) and identified intervention trials (n = 103), inclusive of all ages and countries, to elucidate key learnings about the state of the science. This review provides a critical appraisal of the scientific literature related to multilevel obesity interventions and includes a description of their effectiveness on adiposity outcomes and prominent characteristics (e.g., population, setting, levels). Key objectives for future research are recommended to advance innovations to improve population health and reduce obesity.

Reduced exercise capacity for muscle mass in adolescents living with obesity

BACKGROUND

Adolescents living with obesity (AlwO) can have limited exercise capacity. Exercise capacity can be predicted by a 2-factor model comprising lung function and leg muscle function, but no study has looked at cycling leg muscle function and its contribution to cycling exercise capacity in AlwO.

METHODS

Twenty-two nonobese adolescents and 22 AlwO (BMI > 95 percentile) were studied. Anthropometry, body composition (dual-energy X-ray absorptiometry), spirometry, 30-s isokinetic work capacity, and maximal exercise (cycle ergometry) were measured.

RESULTS

AlwO had greater total body mass, lean body mass, and lean leg mass (LLM). Lung function trended higher in AlwO. Leg 30-s work did not differ in absolute terms or per allometrically scaled LLM. Peak oxygen consumption did not differ between the groups in absolute terms or as percent predicted values (79.59 ± 14.6 vs. 82.3 ± 11.2% predicted control versus ALwO) but was lower in AlwO when expressed per kg body mass, kg lean body mass, scaled lean body mass, and LLM. Peak oxygen consumption related to both lung function and 30-s work, with no observed group effect. 30-s leg work related to the scaled LLM, with a small group effect. There was some correlation between leg work and time spent in moderate to vigorous physical activity in AlwO (rs = 0.39, p = .07).

CONCLUSION

AlwO have larger LLM and preserved exercise capacity, when expressed as percentage of predicted, but not per allometrically scaled LLM. Increasing time spent in moderate to vigorous activity may benefit AlwO.

American Heart Association's Children's Strategically Focused Research Network Experience

The American Heart Association's Strategically Focused Children's Research Network started in July 2017 with 4 unique programs at Children's National Hospital in Washington, DC; Duke University in Durham, North Carolina; University of Utah in Salt Lake City, Utah; and Lurie Children's Hospital/Northwestern University in Chicago, Illinois. The overarching goal of the Children's National center was to develop evidence-based strategies to strengthen the health system response to rheumatic heart disease through synergistic basic, clinical, and population science research. The overall goals of the Duke center were to determine risk factors for obesity and response to treatment including those that might work on a larger scale in communities across the country. The integrating theme of the Utah center focused on leveraging big data-science approaches to improve the quality of care and outcomes for children with congenital heart defects, within the context of the patient and their family. The overarching hypothesis of the Northwestern center is that the early course of change in cardiovascular health, from birth onward, reflects factors that result in either subsequent development of cardiovascular risk or preservation of lifetime favorable cardiovascular health. All 4 centers exceeded the original goals of research productivity, fellow training, and collaboration. This article describes details of these accomplishments and highlights challenges, especially around the COVID-19 pandemic.

The longitudinal association between asthma severity and physical fitness among new York City public school youth

Severe persistent childhood asthma is associated with low physical activity and may be associated with poor physical fitness. Research on the asthma severity-fitness association longitudinally and across sociodemographic subgroups is needed to inform fitness interventions targeting youth with asthma. We evaluated the relationship between asthma severity (categorized as severe, mild, or no asthma) and subsequent fitness in New York City (NYC) public school youth enrolled in grades 4-12 using the NYC Fitnessgram dataset (2010-2018). Longitudinal mixed models with random intercepts were fit to test the association between asthma severity and one-year lagged fitness z-scores by clustering repeated annual observations at the student level. Models were adjusted for sex, race/ethnicity, grade level, poverty status, time, and stratified by sociodemographic factors. The analytic sample included 663,137 students (51% male; 31% non-Hispanic Black, 40% Hispanic; 55% in grades 4-8, 70% high poverty; 87%, 11% and 1% with no, mild, and severe asthma, respectively). Students with severe asthma and mild asthma demonstrated -0.19 (95% CI, -0.20 to -0.17) and - 0.10 (95% CI, -0.11 to -0.10), respectively, lower fitness z-scores in the subsequent year relative to students without asthma. After stratifying by demographics, the magnitude of the asthma severity-fitness relationship was highest for non-Hispanic white vs. all other racial/ethnic subgroups, and was similar across sex, grade level, and household poverty status. Overall, we observed an inverse longitudinal relationship between asthma severity and subsequent fitness among urban youth, particularly non-Hispanic Whites. Future research should examine how neighborhood-level factors impact the asthma severity-fitness relationship across racial/ethnic subgroups.

Severe obesity and fitness in New York City public school youth, 2010-2018

BACKGROUND

Obesity is associated with poorer youth fitness. However, little research has examined the magnitude of this relationship in youth with severe obesity. Therefore, we sought to determine the relationship between increasing weight status and fitness within a sample of children and adolescents from New York City public schools.

METHODS

This study utilized longitudinal data from the NYC Fitnessgram dataset years 2010-2018. Height and weight along with fitness were measured annually during physical education classes. Severity of obesity was defined using body mass index relative to the 95th percentile and then categorized into classes. A composite measure of fitness was calculated based on scores for three fitness tests: aerobic capacity, muscular strength, and muscular endurance. To examine the weight status-fitness relationship, repeated measures mixed models with random-intercepts were constructed. Stratified models examined differences by demographic factors.

RESULTS

The sample included 917,554 youth (51.8% male, 39.3% Hispanic, 29.9% non-Hispanic Black, 14.0%, 4.6%, and 1.6% class I, II and III obesity, respectively). Compared to youth with healthy weight, increasing severity of obesity was associated with decreased fitness: overweight (β = - 0.28, 95% CI:-0.29;-0.28), class I obesity (β = - 0.60, 95% CI:-0.60; - 0.60), class II obesity (β = - 0.94, 95% CI:-0.94; - 0.93), and class III obesity (β = - 1.28; 95% CI:-1.28; - 1.27). Stratified models showed the association was stronger among male and non-Hispanic White youth.

CONCLUSION

Findings revealed that more severe obesity was associated with lower fitness. Future research is needed to develop targeted interventions to improve fitness in youth with obesity.