Exercise training improves breathing strategy and performance during the six-minute walk test in obese adolescents

Effects of obesity on pulmonary function considering the transition from obstructive to restrictive pattern from childhood to young adulthood

Adults with obesity exhibit a restrictive pattern, whereas children with obesity exhibit an obstructive pattern. However, the transition process remains unclear. We performed a systematic search for studies reporting on body mass index and pulmonary function in children. The main outcomes were forced expiratory volume in 1 s (FEV₁ ), forced vital capacity (FVC), and their ratio (FEV₁ /FVC). We compared individuals with overweight or with obesity with individuals with normal weight. Random-effects models were used to calculate pooled estimates. A total of 17 studies were included. Individuals with obesity had a lower FEV₁ /FVC ratio (mean difference [MD] = -3.61%; 95% confidence interval [CI] = -4.58%, -2.64%) and a higher percent-predicted FVC (MD = 3.33%; 95% CI = 0.79%, 5.88%) than those with normal weight. Obesity impaired pulmonary function in the obstructive pattern during childhood to young adulthood, and the maximum obstruction was observed at the age of 16 years in boys and 20 years in girls. The effects attenuated at approximately 30 years and then shifted to the restrictive pattern after 35 years of age in men and 40 years in women. The effects of obesity on pulmonary function change from the obstructive pattern in childhood to the restrictive pattern in adulthood.

Expiratory Flow Limitation at Different Exercise Intensities in Coronary Artery Disease

Introduction

Expiratory flow limitation (EFL) during moderate intensity exercise is present in patients with myocardial infarction (MI), whereas in healthy subjects it occurs only at a high intensity. However, it is unclear whether this limitation already manifests in those with stable coronary artery disease (CAD) (without MI).

Materials and Methods

Forty-one men aged 40–65 years were allocated into (1) recent MI (RMI) group (n = 8), (2) late MI (LMI) group (n = 12), (3) stable CAD group (n = 9), and (4) healthy control group (CG) (n = 12). All participants underwent two cardiopulmonary exercise tests at a constant workload (moderate and high intensity), and EFL was evaluated at the end of each exercise workload.

Results

During moderate intensity exercise, the RMI and LMI groups presented with a significantly higher number of participants with EFL compared to the CG (p < 0.05), while no significant difference was observed among groups at high intensity exercise (p > 0.05). Moreover, EFL was only present in MI groups during moderate intensity exercise, whereas at high intensity all groups presented EFL. Regarding the degree of EFL, the RMI and LMI groups showed significantly higher values at moderate intensity exercise in relation to the CG. At high intensity exercise, significantly higher values for the degree of EFL were observed only in the LMI group.

Conclusion

The ventilatory limitation at moderate intensity exercise may be linked to the pulmonary consequences of the MI, even subjects with preserved cardiac and pulmonary function at rest, and not to CAD per se.

Obesity and asthma

Obesity is a vast public health problem and both a major risk factor and disease modifier for asthma in children and adults. Obese subjects have increased asthma risk, and obese asthmatic patients have more symptoms, more frequent and severe exacerbations, reduced response to several asthma medications, and decreased quality of life. Obese asthma is a complex syndrome, including different phenotypes of disease that are just beginning to be understood. We examine the epidemiology and characteristics of this syndrome in children and adults, as well as the changes in lung function seen in each age group. We then discuss the better recognized factors and mechanisms involved in disease pathogenesis, focusing particularly on diet and nutrients, the microbiome, inflammatory and metabolic dysregulation, and the genetics/genomics of obese asthma. Finally, we describe current evidence on the effect of weight loss and mention some important future directions for research in the field.

Overweight, Obesity, and Lung Function in Children and Adults-A Meta-analysis

BACKGROUND

There is conflicting evidence on the effect of obesity on lung function in adults and children with and without asthma. We aimed to evaluate the relation between overweight or obesity and lung function, and whether such relationship varies by age, sex, or asthma status.

METHODS

We searched PubMed, Scopus, CINAHL, Cochrane, and EMBASE for all studies (in English) reporting on obesity status (by body mass index) and lung function, from 2005 to 2017. Main outcomes were forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC, forced expiratory flow between 25th and 75th percentile of the forced vital capacity (FEF25-75), total lung capacity (TLC), residual volume (RV), and functional residual capacity (FRC). Random-effects models were used to calculate the pooled risk estimates; each study was weighed by the inverse effect size variance. For each outcome, we compared overweight or obese ("obese") subjects with those of normal weight.

RESULTS

All measures of lung function were decreased among obese subjects. Obese adults showed a pattern (lower FEV1, FVC, TLC, and RV) different from obese children (more pronounced FEV1/FVC deficit with unchanged FEV1 or FVC). There were also seemingly different patterns by asthma status, in that subjects without asthma had more marked decreases in FEV1, TLC, RV, and FRC than subjects with asthma. Subjects who were obese (as compared with overweight) had even further decreased FEV1, FVC, TLC, RV, and FRC.

CONCLUSIONS

Obesity is detrimental to lung function, but specific patterns differ between children and adults. Physicians should be aware of adverse effects of obesity on lung function, and weight control should be considered in the management of airway disease among the obese.

Changes in Functional Mobility and Musculoskeletal Pain After Bariatric Surgery in Teens With Severe Obesity: Teen-Longitudinal Assessment of Bariatric Surgery (LABS) Study

IMPORTANCE

Severe obesity is associated with mobility limitations and higher incidence of multijoint musculoskeletal pain. It is unknown whether substantial weight loss improves these important outcomes in adolescents with severe obesity.

OBJECTIVE

To examine the association of bariatric surgery with functional mobility and musculoskeletal pain in adolescents with severe obesity up to 2 years after surgery.

DESIGN, SETTING, AND PARTICIPANTS

The Teen-Longitudinal Assessment of Bariatric Surgery Study is a prospective, multicenter, observational study, which enrolled 242 adolescents (≤19 years of age) who were undergoing bariatric surgery from March 2007 through February 2012 at 5 US adolescent bariatric surgery centers. This analysis was conducted in November 2015.

INTERVENTIONS

Roux-en-Y gastric bypass (n = 161), sleeve gastrectomy (n = 67), or laparoscopic adjustable gastric band (n = 14).

MAIN OUTCOMES AND MEASURES

Participants completed a 400-m walk test prior to bariatric surgery (n = 206) and at 6 months (n = 195), 12 months (n = 176), and 24 months (n = 149) after surgery. Time to completion, resting heart rate (HR), immediate posttest HR, and HR difference (resting HR minus posttest HR) were measured and musculoskeletal pain concerns, during and after the test, were documented. Data were adjusted for age, sex, race/ethnicity, baseline body mass index (calculated as weight in kilograms divided by height in meters squared), and surgical center (posttest HR and HR difference were further adjusted for changes in time to completion).

RESULTS

Of the 206 adolescents with severe obesity included in the study, 156 were female (75.7%), the mean (SD) age was 17.1 (1.6) years, and the mean (SD) body mass index was 51.7 (8.5). Compared with baseline, significant improvements were observed at 6 months for the walk test time to completion (mean, 376 seconds; 95% CI, 365-388 to 347 seconds; 95% CI, 340-358; P < .01), resting HR (mean, 84 beats per minute [bpm]; 95% CI, 82-86 to 74 bpm; 95% CI, 72-76), posttest HR (mean, 128 bpm; 95% CI, 125-131 to 113 bpm; 95% CI, 110-116), and HR difference (mean, 40 bpm; 95% CI, 36-42 to 34 bpm; 95% CI, 31-37). These changes in time to completion, resting HR, and HR difference persisted at 12 months and 24 months. Posttest HR further improved from 6 months to 12 months (mean, 113 bpm; 95% CI, 110-116 to 108 bpm; 95% CI, 105-111). There were statistically significant reductions in musculoskeletal pain concerns at all points.

CONCLUSIONS AND RELEVANCE

These data provide evidence that bariatric surgery in adolescents with severe obesity is associated with significant improvement in functional mobility and in the reduction of walking-related musculoskeletal pain up to 2 years after surgery.

Sleep quality, sleep duration and physical activity in obese adolescents: effects of exercise training

BACKGROUND

Decreased sleep duration and altered sleep quality are risk factors for obesity in youth. Structured exercise training has been shown to increase sleep duration and improve sleep quality.

OBJECTIVES

This study aimed at evaluating the impact of exercise training for improving sleep duration, sleep quality and physical activity in obese adolescents (OB).

METHODS

Twenty OB (age: 14.5 ± 1.5 years; body mass index: 34.0 ± 4.7 kg m(-2) ) and 20 healthy-weight adolescents (HW) completed an overnight polysomnography and wore an accelerometer (SenseWear Bodymedia) for 7 days. OB participated in a 12-week supervised exercise-training programme consisting of 180 min of exercise weekly. Exercise training was a combination of aerobic exercise and resistance training.

RESULTS

Sleep duration was greater in HW compared with OB (P < 0.05). OB presented higher apnoea-hypopnoea index than HW (P < 0.05). Physical activity (average daily metabolic equivalent of tasks [METs]) by accelerometer was lower in OB (P < 0.05). After exercise training, obese adolescents increased their sleep duration (+64.4 min; effect size: 0.88; P = 0.025) and sleep efficiency (+7.6%; effect size: 0.76; P = 0.028). Physical activity levels were increased in OB as evidenced by increased steps per day and average daily METs (P < 0.05). Improved sleep duration was associated with improved average daily METs (r = 0.48, P = 0.04).

CONCLUSION

The present study confirms altered sleep duration and quality in OB. Exercise training improves sleep duration, sleep quality and physical activity.