title: Factors associated with aerobic fitness in adolescents with asthma.
abstract: BACKGROUND
  In adolescents with asthma, information on factors associated with cardiorespiratory fitness levels is limited. The present study aimed to determine if objectively measured physical activity as well as potential relevant factors such as lung function, asthma exacerbations, use of inhaled corticosteroids or skin fold thickness are associated with direct measurements of peak oxygen uptake (V˙O2peak) in adolescents with asthma.
  
  
  METHODS
  From a nested case-control study at 13-years in the Environment and Childhood Asthma birth cohort study in Oslo, Norway, 86 13-years old adolescents with and 76 without asthma performed maximal running on a treadmill with V˙O2peak measured. The sum of four skin fold thicknesses was recorded, followed by wearing an activity monitor for four consecutive days. Lung function was measured by maximum forced expiratory flow-volume curves and body plethysmography. Asthma exacerbations and use of medication were registered by parental structured interview. Data were analysed using multiple regression analysis.
  
  
  RESULTS
  Vigorous physical activity (coefficients with 95% confidence intervals; 1.73 (0.32, 3.14)) and skin fold thickness -0.35 (-0.41, -0.28)) were significantly associated with V˙O2peak in adolescents with asthma. Neither use of inhaled corticosteroids, lung function nor number of asthma exacerbations was associated with V˙O2peak when taking physical activity and skin fold thickness into account. In the adolescents without asthma only skin fold thicknesses was negatively associated with V˙O2peak -3.5 (-4.1, -2.8).
  
  
  CONCLUSIONS
  V˙O2peak appears to be determined by vigorous physical activity level in Norwegian adolescents with asthma and not by asthma-related factors such as use of inhaled corticosteroids, lung function nor number of asthma exacerbations.
authors: Department of Paediatrics, Oslo University Hospital, Oslo, Norway. sveinung.berntsen@uia.no
authors: Sveinung
authors: S
authors: Berntsen
authors: Karin C
authors: KC
authors: Lødrup Carlsen
authors: Sigmund A
authors: SA
authors: Anderssen
authors: Petter
authors: P
authors: Mowinckel
authors: Kai-Håkon
authors: KH
authors: Carlsen
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000503:physiopathology*; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*; D012129:Respiratory Function Tests / Q000379:methods; D012420:Running / Q000502:physiology
keywords: Body fat; Exacerbations; Lung function; Physical activity; Robust regression