## Fibonacci, spirals and human movement--Part I

Fibonacci's numbers are one of the better known mathematical sequences. It is a series of numbers that are based on the sum of the previous two numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34....and so on. These numbers have been found to have representation in many forms throughout nature, architecture, our galaxy....and movement, as will soon be discussed.

Fibonacci's real name is Leonardo Pisano and he was born in the late 12th century in Pisa, Italy. It is only because scholars in the 1400's misinterpreted Leonardo's handwritten copies of his now famous book, Liber Abaci, that he became known as Fibonacci. It is in this book that Fibonacci came up with the question about the growth of rabbit colonies which inspired the now famous number sequence. Incidentally, Liber Abaci is when he first discussed the number system that we still use today. He had learned of similar methods during his travels and discussed that the 0-9 numeric system could be used in different ways for merchants to have commonality vs utilizing different systems from different regions or using the more cumbersome Roman numerals of the day.

Beyond the significance of the number series itself, graphically it is represented as a series of geometric shapes which when added on to each other create a series of "golden rectangles"--meaning, aesthetically a rectangle of optimal proportions. Taking it one step further and introducing a quarter circle into each of the shapes, a spiral is formed. While not a perfect spiral, it is a shape that is seen in nature in a number of different ways: the shape of shells of snails and seashells, fiddleheads, waves, cyclones--even the galaxy itself! Then there is how the ratios of the rectangle equal the number "phi"--1.61803....(ad infinitum), or the "golden ratio", but that's a completely different post altogether.

Now how does it relate to human movement? At the risk of not wanting to just put Fibonacci spirals on top of everything, there are some things which it applies to quite well. The following examples might serve as a useful tool to appreciate the very mechanics of some of the things that have not been thought about before in this manner, and even potentially aid in how one might provide cues during rehab or training.

Let's start with this picture of my daughter Natalie (from a few years ago) doing an awesome hair flip from the water. Certainly the coloring and just coolness factor makes this a fun picture to look at.

But what if we took it and added the spiral representation on top? When you consider this aspect of it, perhaps that might help explain what makes this picture "golden".

So now let's look at sprinting, especially from the starting blocks. Here we have someone who clearly has great lines coming out of the blocks and demonstrates what would be perceived as excellent body position to be as efficient and strong as possible to start a race.

He starts in a very crouched position--in a coiled position, trying to create potential energy at the sound of the pistol start. Now let's see what happens when we apply Fibonacci's spirals as representative of his "core" being the center and the arm and leg motion being the smaller cycles of spiral rotation as he starts, progressing to even larger spirals as he continues through the race. His tightly coiled structure, gradually releasing this kinetic energy helping to essentially sling-shot himself down the track.

Using this same sprinter as an example, and thinking more from an external focus vs internal, one could apply these same spirals in relation to the ground and the sprinter--that the ground is rolling underneath them, essentially coming up to help propel him forward. If he could visually "see" this--proprioceptively seeing the ground rolling up under him while he stares straight ahead down the track--this could very well help through the use of other senses to aid in this skill.

Let's go deeper into human function with these same principles in mind. A nice example of this would be our diaphragm and how it should be positioned in a way so as to allow for optimal lateral thoracic expansion during unconscious resting tidal breathing (regular breathing at rest), unconscious active breathing (as occurs with exercise) and conscious tidal and active breathing (as occurs when one becomes aware and actively changes breath mechanics). The abdominals should be able to actively maintain a down and back position of the ribs to counter this pull of the diaphragm. This helps maintain not only optimal breathing mechanics, but also optimal position of the thorax and pelvis in relationship to each other for function. If we apply Fibonacci's principles to this mechanism, we have a self-contained, rotating spiral of activity. If you'll notice from the purple arrows, they don't all go the same direction. As exhalation begins and the diaphragm starts to ascend, or dome, more posteriorly to start, then working more anteriorly, that coiling will start to wind up and then the front/outer layer should be coming down and back to complete the exhaled cycle. An example of what this might look like it if you had a flexible tape measure you were rolling back up and you wanted to wind it up tight, as you get further into curling it, it works best when you rotate the inside or core part of what has been rolled and then actually pull the outer portion in the ** opposite** direction, much like the outer arrow below, to cinch it up, essentially coiling it tighter. That is a fuller, deeper exhalation which then allows that outer layer (i.e. the abdominals and rib/pelvis position) to maintain this while re-inhalation occurs. A critical component of optimal breath function.

In Part II of this series, we will go deeper into other aspects of how this principles might apply to human structure and function.