Leonardo Da Vinci was inspired by a statement of Vitruvius on the hu­man body inscribed in a circumference and in a square; but to settle the circle onto the square according to his own idea he had to adopt com­pro­mises, because his construct is not real… and it leaks like a sieve.
The much vaunted Vitruvian man, although affecting ± the ‘collective un­con­scious’ of half the world Ø ±, is a false ideographic which boasts a per­fect ratio: that from a man framed into a square to the same inside a circle that wont even fit by itself.
But what is worse, whether Le­on­ar­do Da Vinci did it in who­le aware­ness or not, from the hermetic and subliminal point of view he acted in re­verse of the so much felt leitmotiv of Vitruvius, which albeit reflexly, is mo­st­ly awarded to him with full hands.
That sketch of his, caged the man inside the [phys­i­cal] square, hinting and clip­ping at a time the illusion of being able to move in the circle [of spiritual vibration], a cosmic longing – for those who want to read it – paralyzed by the roof of the head line [worldly rationality, instead of the irrational Golden Ratio?]. Far away from being a microcosm of the uni­verse! Shall we apply such vision of the microcosm to the universe itself?

In a nutshell, the second pair of arms, as for the spread legs, had to be de­vo­ted to the circle and not relegated to the square where instead Le­on­ar­do in­tend­ed to con­fine them, distorting the esoteric, existential and evolutionary sense of the symbolism (and its correct proportions).
Only the solution achieved right here may be the real answer to this an­cient and actual research, and to the Vitruvius intuition and aim; hence if you ex­pect a step forward, here it is:

he heart is the human reference center, i.e. his Golden Ratio within  the Cre­ation Con­scious­ness! This means that starting from the heart we could even geometrically draw all pa­ram­e­ters of the structure of man, either phisical or ultra phisical, provided a cer­tain level of equilibrium is reified.

So, let's become like angels!
From his own detailed an­no­ta­tions we can deduce that the Golden Ratio was not known or familiar to Leonardo.
Nor does this juxtaposition of a circle and a square match the sacred ‘squaring of the circle’, just now re­vealed from the real π.
Though I suppose he can't be held completely responsible for the mis­lead­ing fame of this pat­tern. Could he ever have foreseen how this table, even with its out­stretched arms and shortened legs, would have co­n­qu­ered the world centuries later in full celebrity?
Or was it only the shallowness of oth­ers to have mounted this myth?
So, rather than to his intention to apply it, any search about the Di­vine Pro­por­tion tro­ugh his sketch could take on a meaning right as if done on any av­er­age struc­tu­re of an ideal human body, provided its erect po­si­tion with hor­i­zon­tal­ly out­stret­ched arms de­lin­e­ates the Vitruvian squ­are, since this was the only un­equiv­o­cal framing.
For such a case, that is the path of this study, the Golden Section applies in at least all the ways delined herewith; which was our goal.