Impact of continuous positive airway pressure on the pulmonary changes promoted by immersion in water.

Objective: To determine whether different levels of CPAP improve the lung volumes and capacities of healthy subjects immersed in water.

Methods: This was a randomized clinical trial, conducted between April and June of 2016, involving healthy female volunteers who were using oral contraceptives. Three 20-min immersion protocols were applied: control (no CPAP); CPAP5 (CPAP at 5 cmH2O); and CPAP10 (CPAP at 10 cmH2O).