Improved management of obesity is an urgent public health need. Nearly 40% of US children and adolescents have a body mass index that markedly increases their risk for serious metabolic and cardiopulmonary sequelae. Current childhood obesity rates, for the first time in US history, predict a decline in life US expectancy. Importantly, childhood obesity is a key driver of health disparities in the US, with obesity disproportionately affecting African-American, Hispanic-Latino, and Native American children. A key contributor to the sequelae of obesity is sedentariness. Thus, best practice in obesity management includes both reducing sedentariness and establishing durable increases in daily physical activity, however, attrition from planned exercise programs remains high. A key challenge to initiating and sustaining physical activity in children with obesity is the extreme dyspnea (breathlessness) they experience. This is due to the altered thoracic mechanics of obesity which lead to enhanced inspiratory muscle fatigue and dyspnea, with even modest physical activity. Our group has confirmed that among adolescents, higher body mass index (BMI) associates with lower inspiratory muscle endurance (r= -0.680, p=0.049, n=14), and that this lower endurance correlates with more frequent dyspnea (r= - 0.672, p=0.023, n=12). Treating obesity-related inspiratory muscle impairment and dyspnea is a promising approach to support physical activity in children with obesity but is yet unproven.
This is a single-center, randomized, SHAM-controlled, parallel assignment, double-masked, interventional trial among children aged 8-17 years (not yet 18 years old) of age with obesity (n=30), recruited from the Duke Healthy Lifestyles Clinic to test the effectiveness of inspiratory muscle rehabilitation (IMR) as an acceptable add-on intervention to reduce dyspnea (feeling short-of-breath or breathless) and to promote greater activity in children with obesity