With 14 years of experience in professional holistic massage and receiving over 10 hours of freedive theory from Umberto Pelizzari during 3 of his freedive stages here on Ibiza, I was easily able to put the two together to realise, that freedivers could benefit from a uniquely designed massage for their specific needs.
A freediver has to have good flexibility of his/her body posture in order to freedive with relaxation and be efficient in his/her body position to move through the water most efficiently. Of great importance to a freediver is his breathing ability to breath deep and take extra air. Hence most freedivers do yoga and pranayama (the science of breathing).
the muscles and body areas important for the freediver starting from the top of the body downward would be, neck muscles, shoulder muscles, the back muscles and the muscles on the back of the legs.
Breathing related area and muscles:
for improving breathing and the holding of air in an efficient and relaxed manner, the stomach and stomach muscles and the small intercostal muscles of the rib cage, connecting each rib to the next would be massaged and worked.
To round off such a massage and make it all feel complete one would add feet and head massage.
To expand a little, in freediving the body posture is important for efficient aqua dynamics, to freedive effectively and efficiently. Straight but relaxed body, arms close to body, neck straight and never arched. Specific finning and avoiding muscle cramping.
Hence massaging of the specified physical areas and muscles. And for breathing efficiency as one performs this sport on just one breath of air, one must relax the stomach, it's muscles and have relaxed but as open as possible lungs and rib cage. So massaging of the stomach, ribs and all the little intercostal muscles connecting each rib to the next, is of great value and benefit to a freediver.