Factors associated with aerobic fitness in adolescents with asthma

Physical fitness of children and youth with asthma in comparison to the reference population : Cross-sectional results of the population-based MoMo study in Germany

BACKGROUND

Physical fitness is an essential marker of health. The literature regarding the question of whether individuals with asthma have reduced physical fitness compared to their non-asthmatic peers is inconsistent and focuses on the cardiorespiratory endurance dimension. This study provides a comparison of different dimensions of physical fitness in individuals with and without asthma on the basis of the German population-based study "KiGGS" (German Health Interview and Examination Survey for Children and Adolescents) and its in-depth study "MoMo" (2009-2012: wave 1 and 2014-2017: wave 2).

METHODS

In total, 7731 individuals aged 6-30 years were included in this cross-sectional analysis at two measurement waves, including 353 individuals with and 7378 without asthma. The 12-month prevalence of physician-diagnosed asthma was assessed by interview. Physical fitness was measured by six test items of the MoMo test profile. "Cardiorespiratory endurance" was measured by an ergometric test, "muscular strength" by standing long jump, push-ups and sit-ups and "coordination" by jumping sideways and balancing backwards. Because of the broad age range of the sample, age- and sex-specific percentiles were used. Physical activity, age, gender and general state of health were assessed by questionnaire.

RESULTS

The individuals with asthma reported a poorer general state of health at both measurement waves. However, the results of the fitness tests indicated that they were as physically fit as their peers without asthma in relation to cardiorespiratory endurance and muscular strength. The mean percentiles were all within the same range. The results of the comparisons of coordination performance were inconsistent. At wave 1 they were within the same range, at wave 2 individuals with asthma showed a poorer coordination performance (p = 0.041; HL = 4.125, CI of HL 0.155-8.125).

CONCLUSIONS

To the best of our knowledge, this is the first study to compare the physical fitness of individuals with and without asthma by considering several dimensions of physical fitness. The study demonstrates that cardiorespiratory endurance and muscular strength are not reduced in individuals with asthma. The results of the comparisons at the two measurement waves were remarkably stable.

Low fitness and increased sedentary time are associated with worse asthma-The National Youth Fitness Survey

BACKGROUND

Asthma is the most common chronic illness in children and is independently impacted by obesity and by fitness. The National Youth Fitness Survey collected data on aerobic fitness, body composition, and health outcomes in children 6 to 11 years old. The goal of this study is to test hypotheses regarding relationships between asthma, aerobic fitness, and sedentary time in this uniquely studied cohort of young children.

METHODS

A total of 665 children (6-11 years old; 49% male) were included in analyses. We explored relationships between asthma outcomes and aerobic fitness (measured by endurance time), self-reported sedentary time, and body mass index categories. Fitness was categorized as unfit (lowest 25% of endurance times) or fit. Multivariate logistic regression models were created for asthma outcomes and adjusted for race, age, sex, poverty status, and overweight/obesity.

RESULTS

Among the participants, 17.9% had a previous history of asthma and 11.4% had current asthma. Additionally, 37.3% of participants were overweight or obese. Low fitness was significantly associated with increased odds of past asthma, current asthma, asthma attacks, wheeze with exercise, and wheeze with activity limitations in multivariate models. Increased sedentary time was significantly associated with increased odds of previous asthma, current asthma, asthma attacks, and wheeze with activity limitations.

CONCLUSION

Decreased aerobic fitness and increased sedentary time were associated with worse asthma outcomes in this group of children (6-11 years old). This data suggest that fitness and sedentary time, both modifiable factors, each have an independent effect on asthma and should be included in assessments and management of asthma health.

Asthma, body mass and aerobic fitness, the relationship in adolescents: The exercise for asthma with commando Joe's® (X4ACJ) trial

Although an association has been suggested between asthma, obesity, fitness and physical activity, the relationship between these parameters remains to be elucidated in adolescents. Six-hundred and sixteen adolescents were recruited (334 boys; 13.0 ± 1.1years; 1.57 ± 0.10m; 52.6 ± 12.9kg), of which 155 suffered from mild-to-moderate asthma (78 boys). Participants completed a 20-metre shuttle run test, lung function and 7-day objective physical activity measurements and completed asthma control and quality of life questionnaires. Furthermore, 69 adolescents (36 asthma; 21 boys) completed an incremental ramp cycle ergometer test. Although participants with asthma completed significantly fewer shuttle runs than their peers, peak V̇O₂ did not differ between the groups. However, adolescents with asthma engaged in less physical activity (53.9 ± 23.5 vs 60.5 ± 23.6minutes) and had higher BMI (22.2 ± 4.8 vs 20.4 ± 3.7kg·m-2), than their peers. Whilst a significant relationship was found between quality of life and cardiorespiratory fitness according to peak V̇O₂, only BMI was revealed as a significant predictor of asthma status. The current findings highlight the need to use accurate measures of cardiorespiratory fitness rather than indirect estimates to assess the influence of asthma during adolescence. Furthermore, the present study suggests that BMI and fitness may be key targets for future interventions seeking to improve asthma quality of life.

Altered breathing mechanics and ventilatory response during exercise in children born extremely preterm

Background

Extreme preterm birth confers risk of long-term impairments in lung function and exercise capacity. There are limited data on the factors contributing to exercise limitation following extreme preterm birth. This study examined respiratory mechanics and ventilatory response during exercise in a large cohort of children born extremely preterm (EP).

Methods

This cohort study included children 8–12 years of age who were born EP (≤28 weeks gestation) between 1997 and 2004 and treated in a large regionalised neonatal intensive care unit in western Canada. EP children were divided into no/mild bronchopulmonary dysplasia (BPD) (ie, supplementary oxygen or ventilation ceased before 36 weeks gestational age; n=53) and moderate/severe BPD (ie, continued supplementary oxygen or ventilation at 36 weeks gestational age; n=50). Age-matched control children (n=65) were born at full term. All children attempted lung function and cardiopulmonary exercise testing measurements.

Results

Compared with control children, EP children had lower airway flows and diffusion capacity but preserved total lung capacity. Children with moderate/severe BPD had evidence of gas trapping relative to other groups. The mean difference in exercise capacity (as measured by oxygen uptake (VO₂)% predicted) in children with moderate/severe BPD was −18±5% and −14±5.0% below children with no/mild BPD and control children, respectively. Children with moderate/severe BPD demonstrated a potentiated ventilatory response and greater prevalence of expiratory flow limitation during exercise compared with other groups. Resting lung function did not correlate with exercise capacity.

Conclusions

Expiratory flow limitation and an exaggerated ventilatory response contribute to respiratory limitation to exercise in children born EP with moderate/severe BPD.

A nested case-control study: personal, social and environmental correlates of vigorous physical activity in adolescents with asthma

OBJECTIVE

Physical activity (PA) is associated with health benefits. Children and adolescents with asthma may be limited in their PA, particularly at vigorous intensity due to asthma symptoms or poor psychological adjustment to asthma. We aimed to investigate if self-perceived competence, enjoyment, support from others and social-physical environment were associated with vigorous physical activity (VPA) and secondarily to assess if such associations were modified by asthma and asthma severity.

METHODS

Data from a nested case-control study at 13 years of age within the birth-cohort Environment and Childhood Asthma Study were compiled from 95 participants with and 79 without asthma. The participants completed a questionnaire designed to capture self-perceived competence, enjoyment, support from others and social-physical environment. VPA, defined as ≥ 6 Metabolic Equivalents, was recorded objectively by SenseWear™ Pro2 Armband. Asthma severity was assessed pragmatically by lung function and use of inhaled glucocorticosteroids and β2-agonists and incidence of exacerbations in the last 14 days. Data were analysed using linear regression analysis.

RESULTS

No significant differences between adolescents with and without asthma were identified in terms of VPA, competence-enjoyment, support from others and social-physical environment. Peer support (b = 0.29 (0.05-0.52)) and competence-enjoyment (b = 0.23 (0.01-0.44)) were significantly and positively associated with VPA, and teacher support (b = -0.26 (-0.50 to -0.02)) were inversely associated. The model explained 25% of the variance in VPA.

CONCLUSIONS

Peer support and competence-enjoyment were positively associated with increased VPN in adolescents irrespectively of asthma and asthma severity.