Exercise and Diet Restriction on Cardiovascular Function in Obese Children and Adolescents

Effects of Exercise Training and Diet Restriction on Cardiovascular Function and Their Related Factors in Obese Chinese Children and Adolescents: an Intervention Study

Prevalence rates of childhood obesity have reached alarming levels. As childhood obesity may already be associated with serious comorbidities, obese adolescents are at significantly higher risk for obesity and increased morbidity and mortality during adulthood. Combined lifestyle interventions, which include regular physical activity and dietary restriction, have been shown to result in most significant improvements in cardiovascular function and their associated factors in the pediatric and adolescent population with obesity. The aim of this study is to investigate the effects of a combined exercise and diet intervention on cardiovascular function and their associated factors in obese children.

Sixty obese children and adolescents will complete a 6-week program of exercise and diet intervention. Thirty normal-weight children and adolescents will be recruited as control group. Clinical characteristics, body composition, blood biochemistry, and circulating irisin levels of the subjects will be measured before and after 6-week intervention. Endothelial function will be assessed by a flow-mediated dilation test. Circulating exosome-derived miRNAs, exercise-induced epigenetic modifications, circulating irisin levels irisin concentration in plasma and arterial stiffness as well as cardiac autonomic function will be investigated before and after the 6-week intervention. Fecal samples were collected before and after the 6-week intervention for analysis of the compositional and functional changes in the human gut microbiota.

Subjects were provided with energy-restricted diets of 1300-2200 kcal/day based on weight. The energy percentages provided by protein, fat and carbohydrate were 20%, 20% and 60%, respectively, while energy distributions at breakfast, lunch and dinner were 30%, 40% and 30%, respectively. Subjects performed a series of endurance exercise such as bicycling, walking, running, dancing and ball games for 5 hour/day, supplemented with resistance exercise. Training interventions were performed 5-6 day/week for 6 weeks. The exercise program was designed to result in an energy expenditure of 1500-2500 kcal/day.

Inclusion Criteria: Participants aged 7-17 years Participants satisfied the obesity diagnosis criteria is based on "Body mass index reference standards for the screening of overweight and obesity in Chinese children and adolescents" released in 2004, with cut-off points of p(95) for obesity Exclusion Criteria: Metabolic disease Gastrointestinal disease Cardiac disease Taking medications which affected energy expenditure Losing weight in the past three months whether by diet, taking weight-loss medication or more physical exercise than normal

Huang J, Liao J, Fang Y, Deng H, Yin H, Shen B, Hu M. Six-Week Exercise Training With Dietary Restriction Improves Central Hemodynamics Associated With Altered Gut Microbiota in Adolescents With Obesity. Front Endocrinol (Lausanne). 2020 Dec 7;11:569085. doi: 10.3389/fendo.2020.569085. eCollection 2020.

Liao J, Huang J, Wang S, Xiang M, Wang D, Deng H, Yin H, Xu F, Hu M. Effects of exercise and diet intervention on appetite-regulating hormones associated with miRNAs in obese children. Eat Weight Disord. 2021 Mar;26(2):457-465. doi: 10.1007/s40519-020-00869-9. Epub 2020 Feb 18.