Marathoners’ breathing pattern protects against lung injury by mechanical ventilation: a pilot study

Abstract Background: Marathoners use the 2:2 breathing pattern. We hypothesized that this ventilation method may protect against ventilator-induced lung injury.Methods: We studied the 2:2 breathing pattern as a mechanical ventilation mode, by assessing the gas exchange in intact rabbits and the pulmonary protective effects in isolated rabbit lungs. The typical setting of this breathing method was 30 cycles/min of respiratory frequency. The time allocation for one cycle was as follows: 1st inspiratory period, 2nd inspiratory period, 1st expiratory period, and 2nd expiratory period (all 0.3 s long) with intermittent resting periods (all 0.2 s).Results: The 2:2 breathing pattern caused no problems regarding the efficiency of oxygen uptake and carbon dioxide elimination. The wet-to-dry weight ratio of the lung was lower for the proposed 2:2 breathing pattern than with the inversed ratio ventilation (both inspiratory:expiratory ratio 1:1).Conclusions: The marathoners’ breathing pattern may be a novel method to provide protection against ventilator-induced lung injury in clinical settings.