The Mammalian Dive Reflex

The mammalian dive reflex, also known as diving bradycardia, is an instinctive physiological response that occurs in mammals when submerged in water. It allows mammals to conserve oxygen through slowing the heart rate and redirecting blood to the vital organs. This response is helpful for holding oxygen while underwater, but it has other applications as well. In humans this effect generally occurs when the face is submerged into water, or when water is splashed onto the face. It slows down the heart rate and bloodflow, along with breathing, which can help people slow down their stress response and reach a calmer state. This can also occur with the sudden onset of cold temperatures, such as taking a cold plunge. Diving bradycardia can be a useful tool for people to lower their stress and manage their anxiety when dealing with difficult life circumstances.