Aerobic exercise in adolescents with obesity: preliminary evaluation of a modular training program and the modified shuttle test

BACKGROUND: Increasing activity levels in adolescents with obesity requires the development of exercise programs that are both attractive to adolescents and easily reproducible. The aim of this study was to develop a modular aerobic training program for adolescents with severe obesity, with a focus on variety, individual targets and acquiring physical skills. We report here the effects on aerobic fitness from a pilot study. Furthermore, we examined the feasibility of the modified shuttle test (MST) as an outcome parameter for aerobic fitness in adolescents with severe obesity. METHODS: Fifteen adolescents from an inpatient body weight management program participated in the aerobic training study (age 14.7 ± 2.1 yrs, body mass index 37.4 ± 3.5). The subjects trained three days per week for 12 weeks, with each session lasting 30–60 minutes. The modular training program consisted of indoor, outdoor and swimming activities. Feasibility of the MST was studied by assessing construct validity, test-retest reliability and sensitivity to change. RESULTS: Comparing pretraining and end of training period showed large clinically relevant and significant improvements for all aerobic indices: e.g. VO(2 peak )17.5%, effect size (ES) 2.4; W(max )8%, ES 0.8. In addition, a significant improvement was found for the efficiency of the cardiovascular system as assessed by the oxygen pulse (15.8%, ES 1.6). Construct validity, test-retest reliability and sensitivity to change of the MST were very good. MST was significantly correlated with VO(2 peak )(r = 0.79) and W(max )(r = 0.84) but not with anthropometric measures. The MST walking distance improved significantly by 32.5%, ES 2.5. The attendance rate at the exercise sessions was excellent. CONCLUSION: This modular, varied aerobic training program has clinically relevant effects on aerobic performance in adolescents with severe obesity. The added value of our aerobic training program for body weight management programs for adolescents with severe obesity should be studied with a randomized trial. This study further demonstrated that the MST is a reliable, sensitive and easy to administer outcome measure for aerobic fitness in adolescent body weight management trials

Intensive lifestyle treatment for non-alcoholic fatty liver disease in children with severe obesity: inpatient versus ambulatory treatment

Lifestyle intervention is the only established therapy for non-alcoholic fatty liver disease (NAFLD). The optimal treatment schedule and predictors of response of this treatment have not been established in children. We aimed to evaluate the 2-year efficacy of an inpatient versus ambulatory intensive lifestyle intervention for treating NAFLD in children with severe obesity. A cohort study of 51 severely obese non-diabetic children (mean age 14.7 (±2.4) years; BMI-z-score 3.5 (±0.5)) with liver steatosis were non-randomly allocated to inpatient treatment (2 or 6 months), ambulatory treatment or usual care. Proton Magnetic Resonance Spectroscopy determined liver steatosis and serum alanine aminotransferase (ALT) at 6 months were the primary outcome measures. Baseline variables were evaluated as predictors of treatment response. Liver steatosis had disappeared in 43, 29 and 22% and serum ALT normalized in 41, 33 and 6% at the end of 6 months in the inpatient, ambulatory or usual care treatment groups, respectively. Only the proportions of ALT normalization in inpatient and ambulatory treatment compared with usual care were significantly higher. Treatment effects of inpatient and ambulatory treatment were sustained at 1.5 years follow-up. No baseline characteristic, including PNPLA3 polymorphism or leptin, was consistently predictive for treatment response. A 6-month intensive inpatient and ambulatory lifestyle treatment in children with severe obesity reverses NAFLD in a minority of patients. This study suggests that inpatient compared with ambulatory intensive treatment does not importantly increase treatment success. Further efforts to optimize and individualize lifestyle interventions and additional treatments options are needed particular for children with severe obesity resistant to conventional lifestyle intervention

Gallstone disease in severely obese children participating in a lifestyle intervention program: incidence and risk factors

INTRODUCTION: Cholelithiasis is increasingly encountered in childhood and adolescence due to the rise in obesity. As in adults, weight loss is presumed to be an important risk factor for cholelithiasis in children, but this has not been studied. METHODS: In a prospective observational cohort study we evaluated the presence of gallstones in 288 severely obese children and adolescents (mean age 14.1±2.4 years, body mass index (BMI) z-score 3.39±0.37) before and after participating in a 6-month lifestyle intervention program. RESULTS: During the lifestyle intervention, 17/288 children (5.9%) developed gallstones. Gallstones were only observed in those losing >10% of initial body weight and the prevalence was highest in those losing >25% of weight. In multivariate analysis change in BMI z-score (odds ratio (OR) 3.26 (per 0.5 s.d. decrease); 95% CI:1.60-6.65) and baseline BMI z-score (OR 2.32 (per 0.5 s.d.); 95% CI: 1.16-4.70) were independently correlated with the development of gallstones. Sex, family history, OAC use, puberty and biochemistry were not predictive in this cohort. During post-treatment follow-up (range 0.4-7.8 years) cholecystectomy was performed in 22% of those with cholelithiasis. No serious complications due to gallstones occurred. CONCLUSION: The risk of developing gallstones in obese children and adolescents during a lifestyle intervention is limited and mainly related to the degree of weight loss and initial body weight

Perception of Bronchoconstriction:A Complementary Disease Marker in Children with Asthma

<p>Introduction. Asthma guidelines use symptoms as the most important aspect of asthma control. Symptom perception varies widely between individuals. Over-perception as well as underperception of bronchoconstriction could have a negative effect on asthma management. We hypothesized that perception of bronchoconstriction in childhood asthma is not related to common measures of disease control. For that reason, we examined the clinical determinants of the perception of bronchoconstriction and the repeatability of perception measurements. Patients and methods. In school-age children with moderately severe atopic asthma, we measured the perception of bronchoconstriction (decrease in forced expiratory volume in 1 second (FEV1)) during methacholine bronchoprovocation challenges. The perception of bronchoconstriction was assessed as the slope of the relation between FEV1 and Borg score, and as the Borg score at a 20% decrease in FEV1 from baseline during the provocation test (PS20). Data from subjects who had a 20% or more decrease in FEV1 (n=112) were used for the analysis. Fifty-four children repeated the test after 3 months. Symptoms, use of rescue medication, and peak expiratory flows were scored in diaries during the 2 weeks before testing. Results. Symptom perception was significantly better in children without (PD20 > 1570 mu g, n=28) than in children with airway hyperresponsiveness (PD20</p>