The Mammalian Diving Reflex

A reflex is an involuntary action that your body takes in response to something. You will be familiar with the Patellar or knee-jerk deep tendon reflex, with protective reflexes such as pulling your hand suddenly from pain or heat. Coughing, sneezing, blinking to avoid the impact of an approaching raindrop. There are many types of reflexes.

I wanted to take some time to tell you about the Mammalian Diving Reflex and you will be pleased that I did.

This complex reflex reaction can be clearly observed in aquatic mammals such as dolphins, whales, seals, otters and even – part time semi-aquatic mammals; human beings. In fact all air breathing vertebrates seem to possess the reflex to some extent.

The Mammalian Diving Reflex allows mammals to be submerged under water for increased periods of time. It is also a protection that assists in surviving drowning.

So what happens when this reflex is triggered. The list is long, in short the main effects are bradycardia – a slowing of the heart. The redistribution of blood flow to prioritise the brain and heart, limiting flow to non-essential muscles. Blood pressure lowers. Breathing slows.

These physiological responses are brilliant for helping aquatic mammals survive extended time underwater. But can you think of a situation in a human beings day to day life where the reflex would be useful.

A slowed heart rate, lowered blood pressure, shallow and slow breathing, blood flowing to the brain bringing a sense of calm and wellbeing. Activating the reflex gives us an instantaneous and guaranteed method of resetting an overactive nervous system. Immediately calming anxiety and stress.

So how do you trigger it this miraculous physiological metamorphosis…. Hold your breath and then splash cold water on your face. Yes that’s all it takes. You can also trigger it by putting your face in a bowl of cold water for 30 seconds. Or holding an ice pack on your face while holding your breath.

You already knew this right? Pop culture over the years has taught us this technique. Chuck a glass of water on a panicked individual and they instantly calm. Who knew that this best possible way to calm stress was right there all along.

I only recently learned about this. Using this technique I have calmed after a particularly stressful day, I have even stopped a migraine from kicking in. I have found it to be more effective on headaches than a paracetamol.

Try it, let me know if it helped you.