S
10.1 cm
Within groups p values
Between groups
Two-way Interaction
. 09 ± 5.00 * < 0.001 0.002 0.016
. 35 ± 1.10 * < 0.001 0.002 < 0.001
. 65 ± 19.51 * < 0.001 0.001 0.351
with flat shoes and 3.9 and seven cm shoes . The ability to integrate the sensory systems to maintain the stability of the body ’ s equilibrium was impaired in 10.1 HHS . HHS wearers intended to use a larger portion of vision than proprioception in the postural control process when wearing 10.1 cm HHS . However , the anticipatory postural reactions from proprioceptive receptors played a vital role in maintaining balance , especially in the absence of vision ( Mika et al ., 2016 ). In SOT , the elevated HH may simulate an unstable condition . The sensory condition is more challenged because the support surface and vision are sway referenced . Humans can increase sensory weighting to vestibular and vision information for postural orientation when surrounded by these sway-referenced vision and unstable surfaces ( Horak , 2006 ). Our study demonstrated that hip strategy was adopted more than ankle strategy by HHS wearers with increased HH under interfered conditions . With the increase in HH , the distance of the ankle and hip joints from the line of gravity is reduced ( Stefanyshyn et al ., 2000 ). HHS wearers cannot exert torque at the ankles to rapidly move the body ’ s COM ( Horak & Kuo , 2000 ; Wan , Yick & Yu , 2019 ). A higher percentage of hip strategy is used to generate a larger torque about the hip joint to realign the COG in response to higher HH ( Vanicek et al ., 2013 ). The early activation of the hip flexors may be involved in response to the translation of support surface ( Horak & Kuo , 2000 ). Our study ’ s results are in line with Xiong ’ s study , in which the hip strategy was used because the ankle strategy failed to maintain balance when wearing HHS ( Hapsari & Xiong , 2016 ). The ankle strategy is the first postural control strategy adopted by humans to counteract small perturbations of the COG . On the contrary , hip strategy is used in response to larger perturbations . Human often utilize the combination of ankle and hip strategies for postural correction under external perturbations . The proportion of the strategies that distributed in the postural correction is organized by central nervous system ( CNS ), based on somatosensory input ( Shumway-Cook & Horak , 1986 ). Our study showed that the HHS wearing experience had no significant effect on the overall human postural control . Human postural control is considered a complex motor skill with respect to the support surface , visual environment ,
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