• asthma control;
  • body composition;
  • children;
  • fitness;
  • physical activity.

Background:  Information about how the asthma disease affects the life style and health in children is sparse.

Aim:  To measure fitness, daily physical activity and body composition in children with newly diagnosed, untreated asthma and healthy controls, and to assess the association between the level of asthma control and these parameters.

Methods:  Daily physical activity measured using accelerometry, cardiovascular fitness and body composition (per cent fat, per cent lean tissue and bone mineral density) were measured in 57 children with newly diagnosed, untreated asthma and in 157 healthy age- and sex-matched controls. The level of asthma control was assessed by measurements of a variety of asthma outcomes.

Results:  Children with asthma were less fit (35.1 vs 39.3 ml O2/min/kg) (P < 0.001), had a higher body per cent fat (22.8 vs 19.5%) (P < 0.01) and a higher frequency of overweight (24.6 vs 14.2%) (P < 0.05) than healthy controls. Per cent body fat correlated negativly to overall daily activity (P < 0.001) and to time spent in high or vigorous activity (P < 0.001). Fitness corrrelated positively to time spent in high and vigorous activity (P < 0.001). Within the asthma group, the level of asthma control, fitness and the time spent in vigorous activity correlated positively (P < 0.02).

Conclusion:  Children with untreated asthma are less fit and have a higher body per cent fat and frequency of obesity than their healthy peers. Uncontrolled asthma is associated with a reduced fitness and daytime spent in intensive activity. Overweight children are physically less active than normal weight children.