dynamic touch of effective golf swing
TRANSCRIPT
DYNAMIC TOUCH OF EFFECTIVE GOLF SWING
Wangdo Kim, Antonio Veloso, Maria Machado, Veronica Vleck, Liliana Aguiar, Silvia Cabral
and Filomena Vieira
Biomechanics Laboratory
Faculty of Human Kinetics
Technical University of Lisbon
Estrada da Costa, Cruz Quebrada, Portugal
Introduction
We are revisiting the classic doctrine of “the
significance of left-hand extension during a golfer’s
downswing (Kim 2007).” Recent studies have
suggested that the inertia tensor, a physical property
whose values are time- and coordinate-
independent, may be an important informational
invariant that is used by the proprioceptive system
to control the movement of limbs. We use this
‘dynamic touch paradigm’ to explain why much of
traditional golf instruction has stressed the
importance of a neutral left wrist position,
classically called the ‘flat left wrist. We found that
a skilled golfer may achieve a stronger relationship
between perception and action in terms of their
correlation. The implication of our preliminary
findings about wobbling inertia with respect to the
functioning of the ‘flat left wrist’ are discussed.
Methods
We chose the club’s Instantaneous Screw Axes
(ISA)(Kiat Teu and Kim 2006; Kim and Sean
2011) and principal axes of inertia (e3) (Pagano and
Turvey 1995) and used their instantaneous
successive correspondence during swing as
generating manifolds for the perception to action
diagram. The test conducted to correlate perceptual
learning to skill level was presented as a so-called
‘perception to action’ spatiotemporal diagram that
is based on the two ruled surfaces generated in
terms of 3e � the perceptive information and ISA –
the corresponding actions of players. The 3e traced
out a one-parameter family of ruled surface as the
segment displaces.
Results
The profile of e3, indicative of the correct swing
plane, showed different forms in the expert and
non-expert player: Player A produced a
perturbation in e3 whereas player B produced an e3
shape more uniformly aligned to the path of ISA
(Figure 1 and 2). Greater congruency was observed
in the alignment of the two surfaces in Player B
compared to player A. Moreover, by virtue of
positioning the ISAs alongside the e3 of the club,
Player B achieved such a skilled motion that the
ISAs could be somewhat connected with the
principal inertia axes 3e .
Figure 1: Player A: lesser skilled player.
Figure 2: Player B: Expert player.
Discussion
The perception to action diagram could measure the
disturbing patterns of player-specific swing as a
consequence of a club’s wobbling inertia. Basically
this means that our computational framework offers
a more accurate player-specific model over a
generic model.
References
Kim W. 2007. Response to letter to the editor.
Journal of Biomechanics 40(1):225-225
Kiat Teu K, and Kim W. 2006. J Biomech
39(15):2857-2862.
Kim W, and Sean SK. 2011. Comput Methods
Biomech Biomed Engin in press.
Pagano CC, and Turvey MT. 1995. J Exp Psychol
Hum Percept Perform 21(5):1070-1087.
Presentation 1018 − Topic 41. Sport biomechanics S621
ESB2012: 18th Congress of the European Society of Biomechanics Journal of Biomechanics 45(S1)