Comberiati P, et al. - Researchers focused on characterizing the lung mechanical properties underlying two asthma phenotypes in children, ie, asthma with forced expiratory volume in 1 second (FEV₁) values ≥ 100% of predicted; and asthma with diminished FEV₁. They also focused on the mechanisms defining the paradox of severe asthmatic children, who can have an FEV₁ > 100% of predicted when they are clinically stable, but during an acute bronchospastic episode can experience a life-threatening asthma event. Experts assessed lung mechanics in three categories of children: asthmatics with FEV₁ ≥ 100% (HFEV₁; n = 13), asthmatics with FEV₁ ≤ 80% (LFEV₁; n = 14), and non-asthmatic controls (n = 10). Findings revealed different lung mechanical proprieties among HFEV₁ asthmatic children vs their LFEV₁ asthmatic peers. With the loss of elastic recoil pressure, normal FEV₁ could be produced by the HFEV₁ group because of proportionally enlarged airways and decreased airway resistance, while airflow limitation in the LFEV₁ was attributable to increased airway resistance. A predisposition to catastrophic declines in airflow may develop in the HFEV₁ group because of loss of elastic recoil and interdependence during acute bronchoconstriction episodes.