Figure 2

Lung function and exercise. Average FEV₁ Percent Predicted Trajectories by Exercise Group. Lowess regression of lung function constructed using 2 datapoints per subject (≥10 years old at the time of exercise ascertainment), specifically the baseline FEV₁ and FEV₁ at the end of follow-up based on lung function decline. Subjects were limited to these two points each to avoid overweighting subjects with substantially more FEV₁ measurements. Estimates after 40 years of age may not be as robust owing to fewer older subjects. Although those reporting competitive exercise always appear to have higher lung function than those reporting no exercise, those report recreational exercise only appear to be similar to the no exercise group between ages 10 and 20 years old, then resemble the competitive exercise group in adulthood.