# Influence of haptic Sensory Input through Different Kinds of Clothing on Gait Performance
## 1 Introduction  
Various sensory inputs, such as visual, vestibular, and somatosensory inputs, contribute to the adjustment of balance control during posture maintenance [1]. Haptic sensory information through touching also contributes to balance control. Previous studies reported that although individuals touch a fixed pedestal with an insufficient force to support their own body weight mechanically, postural sway during upright posture is attenuated by the touching cue [2; 3]. This phenomenon is called the \"light touch\" effect. This light-touch effect is observed not only with a fixed pedestal, but also with unstable objects such as cloth curtains [4], canes [5; 6], the individual's own body [7], and other individuals [8; 9]. Such haptic information through light touch is thought to enhance individual perception of body orientation [10]. Therefore, light touch enhances the existing sensation of the body or body segments and contributes to an individual's perception of the relative changes in the position or direction of the trunk, arms, thighs, and so on. Light touch contributes to balance control not only in certain postures, but also for postural control during motion. The functional reach test, known as the dynamic balance measure, is improved by light touch [11]. During constant-speed gait on a treadmill with eyes closed, the center of the body sway was attenuated by light touch to the side rail [12]. Even during gait on the ground with eyes closed, the mediolateral step width variability was decreased while touching a fixed object on the side of the walking lane [13]. These results suggest that various balance controls while performing daily activities may be enhanced by light touch. Furthermore, if the light touch effect can be provided by personal belongings, it will be useful for improving human movements in daily activities. Although postural stability is improved by light touch, the effects of light touch on gait speed are inconsistent. [PERSON] et al. [14] reported in their review that the effects of light touch on gait speedand step length may depend on the type of tool used. [PERSON] et al. (2013) reported that gait speed was decreased by light touch, suggesting that adding light touch may add not only haptic information but also attentional demands. Such additional attentional demand is called the \"dual task\" effect and might interfere with gait performance, that is, when an individual generally walks slowly when asked to walk and perform another task ([PERSON] et al., 2013). On the other hand, the light-touch effect is observed not only in active touching but also in passive haptic sensory input ([PERSON] et al., 2013), and it is thought the passive touching could not be an additional attentional demand. In fact, a decrease in gait time was observed during tandem gait on the narrow walkway board with the eyes closed and a fluttering cloth wrapped around the waist and extended to the lower leg (cloth passively touching the lower leg) as compared with wearing only tights ([PERSON] et al., 2013). Therefore, depending on the shape of the garment worn, balance control during locomotion might be enhanced. However, the effect of passive haptic sensory input such as a fluttering or draping cloth on fundamental gait parameters, including gait speed and step length, during normal gait on normal ground (daily conditions) has not been reported. Furthermore, a previous study compared the gait parameters between wearing fluttering clothing and half or short tights. If passive haptic sensory input through wearing clothing was effective for gait performance, wearing only trousers could also be effective. A previous study suggested that individuals can recognize the moving direction (i.e., putting foot forward) on the basis of the fluttering of the cloth ([PERSON] et al., 2013).