FLOATING IN A POOL AND OUR NERVOUS SYSTEMS
I was speaking with a client who owns a swimming school. We were discussing the value, if any, of floating in a swimming pool, or other bodies of water for that matter, for our nervous systems.
I cannot float. I can hardly swim to save my life. Firstly, unless the water is at least 26 °C, I’m not getting in! Secondly, if my feet can’t touch the bottom with my nose above the water, I’m not a keen participant. Thirdly, unless I can clearly see the bottom and what is between my head and my feet, there’s no way I’ll submerge in thát.
As you can see, I don’t exactly have a cosy relationship with water. Don’t even get me going on the whole ice-water-submergence-for-good-mental-health-thing! It’s not going to happen. I once tried to turn the hot water off at the end of a shower to get the emotional benefit of only feeling the cold water. I’ve never felt so violated in my life. My whole body shouted ‘Abuse! Abuse!’ and would have reported me to some authority if it could. I don’t do cold…in any way. Unless it is loads of ice in my zero-alcohol G&T.
So, when my client suggested I practice what I preach and come for lessons to float, I was a little more than apprehensive. I agreed under the following conditions: 1) It’s high summer and properly warm outside, 2) the pool is heated and 3) I can stand at the deep end with my nose above water.
With all the above conditions adhered to, I embarked on calming my nervous system, by going for my first floating lesson.
The benefits, for the nervous system, of floating, are vast.
It offers a sense of “environmental enrichment”. The focus is on rhythmic regulation and the physical properties of the water. We are taking advantage of the hydrostatic pressure of the water on the body. It feels like a hug and acts similarly to a weighted blanket or compression clothing. (To support my warm water need, who wants a cold hug?) Water provides the nervous system with constant proprioceptive input, which, due to the lowering of cortisol, enhances our feeling of physical security and containment.
When we float, our necks must be relaxed and our heads in such a position that our ears are under water, with basically only our mouths and noses sticking out. We breathe in deeply through the mouth, for loads of air in our lungs for buoyancy, and breathe out through the nose. This stops us from inhaling water through our noses, which may feel like drowning and is not conducive to a nervous system in the parasympathetic state.
In this position the water touches the highly sensitive skin around our eyes and noses, which triggers the Mammalian Dive Reflex (MDR); something I’ve never heard of. For others like me, in a nutshell, what happens is: Our heart rate slows down, and blood is redirected to the brain and heart. This instantly shifts the autonomic nervous system into a calmer state.
A bit of a sidebar to MDR
The MDR is essentially a “built-in” biological reset button. It’s an ancient evolutionary survival mechanism found in all mammals, including humans, that optimises our physiology for staying underwater. When our faces hit water (especially water colder than our body temperature), our nervous system immediately prioritizes our hearts and brains over everything else. When the trigeminal nerve (around our eyes and nose) senses a drop in temperature and the presence of water, it triggers three main responses. Firstly, peripheral vasoconstriction happens. This is when our bodies “close the gates” to extremities. Blood-flow to our fingers, toes, and skin is restricted and redirected toward your vital organs. This consolidation of blood-flow acts as a physical “centring” of your energy. Then bradycardia kicks in. Our heart rate drop 10% to 25% almost instantly. By forcing the heart to slow down, the reflex bypasses our conscious “stress thoughts” and forces the body into a state of physiological calm.
MDR is an autonomic override. When we are feeling extremely anxious or activated, our sympathetic nervous systems (Fight-or-Flight) are in the driver’s seat. It can be hard to “think” ourselves out of that state. However, MDR is a parasympathetic trigger. When we trigger it the vagus nerve is activated, the “emergency brake” is pulled on our heart rate and the brain receives a signal that says, “We are in a different environment; we must conserve energy and stay calm.”
Back to floating
When on land, our nervous systems are constantly calculating how to keep us upright against gravity. When we float, the vestibular system (responsible for balance) gets a break. This “unloading” of gravitational processing allows the brain to reallocate energy toward internal repair and emotional processing rather than external orientation.
The rhythmic, gentle rocking of pool water acts as a low-frequency vibration. This movement can stimulate the vagus nerve which helps improve heart rate variability (HRV), which is a key marker of stress resilience.
After a few lessons, 3 so far, I still cannot float: not even close. My legs won’t stop dropping to the bottom. Mostly, I really struggle to relax, especially my neck. So much of floating feels counter-intuitive for me, from breathing in through the mouth, to relaxing in water, to name but a few.
Yet, when I leave my lesson, I feel amazing! I feel calm and relaxed. I can definitely feel the benefits of what we’re trying to achieve, so, I’ll be going back for more.
Maybe this old dog can be taught a new trick.