Background Aiming at the problem of pilots with poor acceleration endurance, the effects of hyperbaric oxygen pretreatment (HBOP) on improving the lower body negative pressure endurance and centrifuge acceleration endurance of pilots with poor acceleration endurance were investigated. Methods Thirty pilots with poor acceleration endurance were subjected to multiple hyperbaric oxygen chambers and 3 oxygen exposures. The lower body negative pressure endurance, centrifuge acceleration endurance, blood pressure (BP), heart rate (HR),blood lactic acid (BLA), hydrogen ion concentration, partial pressure of carbon dioxide (PCO2), partial pressure of oxygen (PO2) and adrenal corticotropic hormone (ACTH) were measured before and after HBOP. Results The cumulative stress index increased after HBOP compared with before HBOP (P
