Free-diving or breath-hold diving has been around for hundreds, perhaps even thousands, of years. It is our most ancient means to enter the sea to hunt and gather what we need. Personally, I started diving on a single breath of air more than 40 years ago. I began by holding onto my father’s neck when he swam underwater in the swimming pool. This progressed to my first introduction to diving in the sea while on vacation at age seven in Hawaii. From then on my father, a scuba instructor and search-and-rescue diver, began to teach my brother and me how to free-dive and, eventually, to scuba-dive.
His rationale for starting with free-diving was that it developed a level of skill and understanding of the aquatic environment that would be of great benefit to divers when they donned a tank and regulator at a later stage. He also argued that although free-diving was simpler in terms of the equipment required, it was more complicated in the physical effort and technique needed to be proficient. The investment made in learning to free-dive well would make for much easier diving on scuba later.
My father said too that free-diving instils in you a greater respect for the underwater world and that respect would foster a desire to look after the sea and preserve it for the future. It turns out he was right. I have taught countless scuba-divers to free-dive and although not all of them continued after the course, they all said how invaluable it was to learn the basic skills and breathing techniques because it made them more efficient at breathing and thus improved their experience on scuba. At the same time, it gave them a greater appreciation for the sea.
I am of the opinion that all forms of diving have their place, whether they be used for sport and recreation or for conservation. Rebreather diving, mixed-gas diving, diving on air and free-diving all have their strengths and weaknesses, risks and rewards. What I would like to share here is my perspective as someone who is certified for advanced open-water scuba-diving, but who primarily uses free-diving as an active tool either to explore and discover our underwater world or to aid scientific research – or both.
When teaching free-diving, I often speak of a ‘sense of belonging’. There is an innate sense that we belong in the sea when we are diving below its surface on a single breath of air. Some people describe it as a feeling of connection to our ancestry or other marine mammals, but whether or not this is so, that sense of belonging is indisputable: we do, in fact, belong in the sea. After all, we have the same physiological response to it that other marine mammals have.
Like dolphins, whales, seals and other marine mammals, we have what is known as a ‘mammalian diving reflex’. This reflex activates when you put your face in the water. It slows the heart rate, shunts or moves the blood from the arms and legs to the body core and causes the spleen to release old red blood cells back into circulation. Oxygenated blood is prioritised for the heart and brain as they are crucial to our survival; the other organs are temporarily put on hold as the body attempts to safely prolong your time under the water.