Sunday, January 13, 2008

7.7 Sharp shooters

(Qin Dynasty, 221-206BC, standing archer)

Sharp shooters are most likely endowed with unique physiological characteristics. Ideally, they should have 20/15 or better vision with miotic pupils (<2.5mm, even at night), no dry eyes or glare sensitivity (i.e., ocular media remain clear), supplemented with better than average eye-hand coordination and a well-regulated adrenal gland a la Mr John Glenn.

Before the advent of guns and rifles, there were famous sharp-shooting archers. The best known are the horseback riding Mongols led by Genghis Khan - now a popular competitive sports in modern day Mongolia. A stylized form is the Japanese ritual archery, known as Yabusame (流鏑馬). Then there were such accomplished individual archers as Hou-Yi (后羿), Yue Fei (岳飛), Nasu no Yoichi (那須与一), Wilhelm Tell, Robin Hood, et al, all of whom were noted for their supernatural aims and spectacular deeds.

There are parallels in training an archer and a sharp shooter - assuming he/she has passed the ocular physical. We will now go historical and discuss the archer training. It is a combination of whether the person is on foot or on a horseback, and whether the targets are stationary or moving. Training is based on relative motion. The fundamentals, however, are still visual acuity enhancing and eye-tracking. The handling of the bow and arrow is largely mechanical (although it has been decreed that the two hands must be posed such that the left hand is like upholding the Tai Mountain [泰山] straight and taut, and the right, cradling a baby).

Let's start by looking at some legends popular in China.

For visual acuity enhancement, a famed archery instructor tied a flea with a hair from the ox tail, dangled the contraption from under the top window sill and the student was to stare at the flea from across the room, without blinking, until the morphological details could be discerned. For three years, the student practiced this visual training until the flea appeared as big as a cartwheel. By then, he could easily shoot an arrow through its heart. This story was recorded in a Shang Dynasty (1600-1046BC) document (列子.湯問). (Modern day shooters instead use a telescope.)

And Lesson No 2 - eye tracking: a skilled archer was to be able to hit, at 100 paces away, the branches of a willow tree swaying in the gentle breeze. Again, practice makes perfect. General Li Guang (李廣, ? - 119BC) of the Han Dynasty was a huge success at this game. In fact. legend has it that General Li, with his long and powerful arms, once shot a tiger at a long distance. Which turned out to be a tiger-like rock formation, yet the arrow was so deeply embedded as if it had penetrated the flesh.

Hmm..., if you really think about it, the training methods described above are still in use today; albeit in different formats and for entirely different purposes.

One is the well-known Bates method and its modern variations. The claim is that by relaxing extraocular muscles, the degree of myopia can be decreased to a point when glasses are no longer needed. However, this unique theory of accommodation is unsupported by physiological evidence; in which, the ciliary muscle alone is involved. In other words, you can exercise the EOMs all you want, it still won't change an iota of your accommodation.

The other is vision training/eye tracking, very popular among pro baseball players, or more accurately training of visual skills that involve dynamic vision, eye tracking/focusing, depth perception, fusion, and peripheral vision. There is, however, little consensus on the efficacy of this type of vision training. As usual, there are both believers and skeptics.

Amazing, isn't it? After 2-3 thousand years and people are still confused especially when legends, pseudo-science, and real science still collide.

1 comment:

Margla Clerk said...

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