According to the International Golf Federation (IGF), early variants of the game were played in the Roman Empire as early as 100 B.C. Impressively, it accounts for 45% of the total number of facilities around the world (Golf Around the World 2015). The 2011 Golf Economy Report proved the popularity and prominence of the sport.
The downswing occurs when the golfer reaches the top of the backswing through ball contact with the goal of increasing speed. From this, it can be assumed that the characteristics of the styles chosen for this study will cause differences in the balance results. Center of pressure: the average point of the surface area in contact with the ground; the point at which the vertical ground reaction force vector is exerted (Winter 1995).
Muscle spindle: somatosensory receptors within the intrafusal fibers of the muscle belly that detect stretch and rate of stretch (Crowe & Matthews 1964). Peripheral nervous system: division of the nervous system that receives sensory information, transmits the information to the central nervous system, and sends commands from the central nervous system to effector systems (Winter 1990). Swing velocity: speed of postural sway (Chander, Wade, & Garner 2014) Vestibular system: within the inner ear; detect linear and angular accelerations of the head (Purves, Augustine, Fitzpatrick et al. 2001).
It is through either antero-posterior (A/P) or mediolateral (M/L) displacement of the COP in response to COG movement that balance is achieved. The legs act as a stabilizing point, while the rest of the body can sway in the A/P and M/L directions in response to muscular forces trying to find balance (Corbeil et al. 2003). All three of these systems contain sensory organs that transmit information about the individual's state of equilibrium to the central nervous system for evaluation (Hosoda 1997).
This is achieved through the otolith organs, utricle and sacculus, in the inner ear. The utricle records linear accelerations of the head in the horizontal plane, while the sacculus records them in the vertical plane. The combined proprioceptive information provided by the Golgi tendon organs and muscle spindles informs the central nervous system about the current state of the skeletal muscular system (Kistemaker et al. 2013).
Small perturbations during rest cause the COG to move to the periphery of the BOS and challenge the ankle strategy. The plantar flexors and dorsiflexors will flex alternately until the inverted pendulum balance is reestablished (Winter 1990). The soles of the feet contain many nerve endings that send crucial sensory information to the central nervous system for balance.
When the sole of the foot is not exposed to the ground, the amount of sensory information it receives from the cutaneous receptors is reduced (Hosoda et al. 1997).
METHODOLOGY METHODOLOGY
These movements attempt to manipulate the individual's sensory systems in order to assess standing balance. SOT uses the following four test conditions: eyes open (EO), eyes closed (EC), eyes open oscillate referenced gaze (EOSRV), and eyes open oscillate referenced platform (EOSRP). Participants wore one of the following four shoe conditions for each session: barefoot condition, a traditional dress style shoe, a tennis shoe style, and a minimalist shoe style.
Each participant completed four sessions of data collection separated by at least 72 hours; each session lasted approximately four hours. Subjects were asked not to exercise their lower limbs for at least 48 hours before the test. During this visit, the test days' procedures were described, and the participants performed a practice SOT test.
On each of the four test days, an initial SOT test was performed to serve as baseline measurements for data analysis. After the initial SOT, the subject was then instructed to walk at their normal pace on artificial grass for the duration of four hours. The subjects were allowed to stand still for short periods, but they could not sit down or leave the grass field except to perform the SOT tests.
Every hour from the SOT start time, subjects performed the SOT test to assess standing balance over time in each type of shoe. SPSS 22 statistical software analyzed SOT results with a 4 x 5 repeated measures analysis of variance (ANOVA) using a preset alpha level of p < 0.05. The four footwear conditions (barefoot, wear shoe, tennis shoe, and minimalist shoe) were crossed five times (at 240 minutes) for each of the SOT conditions.
RESULTS
DISCUSSION
Over the course of the four-hour study, it was found that balance generally declined over time. When evaluating time interactions with shoe conditions, results revealed that the barefoot condition had better balance than the tennis shoe style at the second hour point. The advantage of having the feet in contact with the environment seemed to outweigh the limited support provided by the shoes.
However, all three golf shoe conditions showed statistically better balance performance than the barefoot condition after three hours. Prolonged standing and walking could have reduced the sensitivity of the skin receptors in bare feet (Corbeil et al. 2003). As previously mentioned, no significant differences were found when comparing balance scores between the three golf shoe styles for the SOT conditions.
The three styles used in this study were not designed with a heel height greater than 1.5 inches; the level at which the balance decreases is starting to become visible. However, none of the three shoes had ankle shafts high enough to cover the malleolus. The only equilibrium-affecting feature supported by previous literature that the three styles possessed was increased mass.
This could be part of the reason why golf shoes have better balance results over a longer period of time than bare feet. The reason why there were no statistically significant differences in balance performance may be because heel heights, ankle heights and masses were not significantly different. We can conclude that none of the three shoe styles from this study would be more detrimental to static balance than the others.
The effects of stimulation of static and dynamic fusimotor fibers on the response to stretch of the primary endings of muscle spindles. Identification of the biomechanical performance determinants of the 5-iron golf swing when hitting for maximum distance (Doctoral dissertation, Dublin City University). The effect of different types of shoes and materials, and of the fixation of the ankles by shoes, on upright postural control.
