Hold your breath: peripheral and cerebral oxygenation during dry static apnea

Purpose Acute breath-holding deprives the human body from oxygen. In an effort to protect the brain, the diving response is initiated, coupling several physiological responses. The aim of this study was to describe the physiological responses to apnea at the cardiac, peripheral and cerebral level. Methods 31 physically active subjects (17 male, 14 female, 23.3 ± 1.8 years old) performed a maximal static breath-hold in a seated position. Heart rate (HR), muscle and cerebral oxygenation (by means of near-infrared spectroscopy, NIRS) were continuously measured. RM MANOVA’s were used to identify changes in HR, peripheral (mTOI) and cerebral (cTOI) tissue oxygenation and oxygenated (O 2 Hb) and deoxygenated (HHb) hemoglobin during apnea. Results Average apnea duration was 157 ± 41 s. HR started decreasing after 10 s ( p