Initial Swing Research Articles

Effect of taping on multi-segmental foot kinematic patterns during walking in persons with chronic ankle instability.

To evaluate multi-segmental foot kinematic patterns in chronic ankle instability (CAI) participants during walking, and to investigate the influence of high-Dye and low-Dye taping on these kinematic patterns. Cross-sectional study. Kinematic data of 12 non-injured controls and 15 CAI participants were measured with a three-dimensional motion analysis system during barefoot walking. In addition, the CAI participants walked with high-Dye and low-Dye taping. A rigid Plug-in gait model and the Rizzoli 3D Multi-Segment Foot Model were used to measure multi-segmental foot kinematic patterns. One-dimensional statistical parametric mapping was used to compare barefoot walking of the control and CAI group, and to evaluate differences between walking barefoot and walking with high-Dye and low-Dye taping within the CAI group. Compared to the control group, CAI participants showed a decreased ankle dorsiflexion during loading response (p=0.025) and a more inverted calcaneus in relation to the shank during the initial swing phase (p=0.024). A more inverted position of the metatarsus in relation to the midfoot was observed after low-Dye taping during almost the entire stance phase (p=0.017). No significant differences were found for high-Dye taping. Significant differences in kinematic patterns were found in the ankle joint and rearfoot, but not in the mid- and forefoot in CAI participants. The application of low-Dye taping resulted in a significantly increased inverted position of the forefoot, which can be considered as a less desirable effect for patients with CAI. No other effects of high-Dye and low-Dye taping on kinematic patterns were revealed.

Cerebral palsy: Influence of TheraTogs ® on gait, posture and in functional performance

Abstract Introduction: For children with cerebral palsy, orthoses take an important role in improving posture, gait, functional performance and preventing secondary musculoskeletal disorders. Objective: To evaluate the influence of TheraTogs® on the posture, distribution of plantar pressure during gait and functional performance of a child with spastic diplegia cerebral palsy. Methods: A quantitative evaluation was carried out on a case study in which an 11-year-old child diagnosed with diplegic cerebral palsy underwent postural assessment through the Postural Assessment Software (PAS), plantar pressure distribution assessment during barefoot gait through the Emed-X system, before and after the intervention period of 8 weeks and functional assessment (Pediatric Evaluation of Disability Inventory - PEDI), with and without TheraTogs®. Results: In posture, TheraTogs® had greater influence on hip extension and this change was greater during its use. In the plantar pressure distribution assessment, an increase in posteriorization of plantar pressure occurred in the initial contact, the performance of the push-off phase and initial swing phase improved. In functionality, the child showed improvements in mobility, however, their self-care ability with TheraTogs® was reduced. Conclusion: Although improvements in posture, gait and functionality were verified with the use of TheraTogs®, the excessive heat, difficulties in toileting and self-care were disadvantages in wearing TheraTogs®.

Constraints on perception of information from obstacles during foot clearance in people with chronic stroke.

The aim of this study was to examine effects of different types of task constraints on coupling of perception and action in people with chronic stroke when crossing obstacles during a walking task. Ten participants with hemiplegic chronic stroke volunteered to walk over a static obstacle under two distinct task constraints: simple and dual tasks. Under simple task constraints, without specific instructions, participants walked at their preferred speed and crossed over an obstacle. Under dual task constraints, the same individuals were required to subtract numbers whilst walking. Under both distinct task constraints, we examined emergent values of foot distance when clearing a static obstacle in both affected and unaffected legs, measured by a 3D motion tracking system. Principal component analysis was used to quantify task performance, and discriminant analysis was used to compare gait performance between task constraints. Results suggested that patients, regardless of affected body side, demonstrated differences in perception of distance information from the obstacle, which constrained gait differences in initial swing, mid-swing, and crossing phases. Furthermore, dual task constraints, rather than hemiplegic body side, were a significant discriminator in patients' perceptions of distance and height information to the obstacle. These findings suggested how performance of additional cognitive tasks might constrain perception of information from an obstacle in people with chronic stroke during different phases of obstacle crossing, and thus may impair their adaptive ability to successfully manoeuvre around objects.

Optimal design of a magnetorheological damper used in smart prosthetic knees

In this paper, a magnetorheological (MR) damper is optimally designed for use in smart prosthetic knees. The objective of optimization is to minimize the total energy consumption during one gait cycle and weight of the MR damper. Firstly, a smart prosthetic knee employing a DC motor, MR damper and springs is developed based on the kinetics characteristics of human knee during walking. Then the function of the MR damper is analyzed. In the initial stance phase and swing phase, the MR damper is powered off (off-state). While during the late stance phase, the MR damper is powered on to work as a clutch (on-state). Based on the MR damper model as well as the prosthetic knee model, the instantaneous energy consumption of the MR damper is derived in the two working states. Then by integrating in one gait cycle, the total energy consumption is obtained. Particle swarm optimization algorithm is used to optimize the geometric dimensions of MR damper. Finally, a prototype of the optimized MR damper is fabricated and tested with comparison to simulation.

Processes of anticipatory postural adjustment and step movement of gait initiation

The purpose of this study was to elucidate whether the anticipatory postural adjustment (APA) and focal step movement of gait initiation are produced as a single process or different processes and whether the APA receives an inhibitory drive from the ongoing stop process of gait initiation. Healthy humans initiated gait in response to a first visual cue that instructed the initial swing leg. In some trials, a switch or stop cue was also provided after the first cue. When the stop cue was provided, participants withheld gait initiation. When the switch cue was provided, participants immediately switched the initial swing leg. In both the stop and switch tasks, the APA in response to the first cue, represented by the S1 period of the displacement of the center of pressure, appeared in more than half of the trials in which the withholding of gait initiation or switching of the initial swing leg was successfully completed. These findings indicate that the APA and focal step movement of gait initiation are produced as a dual process. In trials in which the APA in response to the first cue appeared, the amplitude and duration of the APA were decreased when the participants switched the initial swing leg or withheld gait initiation. This finding indicates that the ongoing stop process of gait initiation produces an inhibitory drive over the APA. The decreases in the amplitude and duration of the APA during the switching of the initial swing leg were similar to those during the withholding of gait initiation; moreover, the decreases during the switching of the initial swing leg were positively correlated with the decreases during the withholding of gait initiation. Thus, the stop processes during switching the initial swing leg and withholding gait initiation likely share a common inhibitory mechanism over the APA.

Constraining movement reveals motor capability in chronic stroke: an initial study

Objective: To determine if persons with chronic stroke and decreased hip and knee flexion during swing can walk with improved swing-phase kinematics when the task demands constrained gait to the sagittal plane. Design: A one-day, within-subject design comparing gait kinematics under two conditions: Unconstrained treadmill walking and a constrained condition in which the treadmill walking space is reduced to limit limb advancement to occur in the sagittal plane. Setting: Outpatient physical therapy clinic. Subjects: Eight individuals (mean age, 64.1 ±9.3, 2 F) with mild-moderate paresis were enrolled. Main measures: Spatiotemporal gait characteristics and swing-phase hip and knee range of motion during unconstrained and constrained treadmill walking were compared using paired t-test and Cohen’s d (d) to determine effect size. Results: There was a significant, moderate-to-large effect of the constraint on hip flexion (p < 0.001, d = –1.1) during initial swing, and hip (p < 0.05, d = –0.8) and knee (p < 0.001, d = –1.1) flexion during midswing. There was a moderate effect of constraint on terminal swing knee flexion (p = 0.238, d = –0.6). Immediate and significant changes in step width (p < 0.05, d = 0.9) and paretic step length (p < 0.05, d = –0.5) were noted in the constrained condition compared with unconstrained. Conclusion: Constraining the treadmill walking path altered the gait patterns among the study’s participants. The immediate change during constrained walking suggests that patients with chronic stroke may have underlying movement capability that they do not preferentially utilize.

Effect of ankle-foot orthoses on gait in children with cerebral palsy: A meta-analysis

Different ankle-foot orthoses (AFO) are often prescribed in children with cerebral palsy (PC) although their efficiency on gait remains unclear. (1) To determine the effect of AFOs on gait in children with CP and (2) to evaluate the effect of each types of AFO. Studies in English with control condition (barefoot or shoes) assessing effect of AFO about children with CP gait were search on the Pubmed, CINAHL+, Web of Science, Cochrane Library databases. Quality of each study was assessed by modified PEDRO scale. Only studies with a score more than 4 were selected. 10 gait parameters were extracted in each study. Effect size and 95% confidence interval were calculated for each parameter. Seventeen studies (490 subjects) were included. Comparing AFOs to control condition, stride length increased (15 studies) d = 1.04 [95% CI: 0.69; 1.38], velocity increased (16 studies) d = 0.27 [95% CI: 0.14; 0.41], cadence decreased (15 studies) d = −0.69, [95% CI: −0.95; −0.43]. Ankle dorsiflexion increased at initial contact (11 studies) d = 1.64, [95% CI: 1.16; 2.11] and in swing phase (7 studies) d = 5.21, [95% CI: 1.91; 8.52]. Ankle power generation in stance phase decreased (6 studies) d = −0.26, [95% CI: −0.38; −0.14]. The duration of tibialis anterior activation and energy data did not changed significantly. Four types of orthosis were found: dynamic AFO, hinged AFO, solid AFO, supra-malleolar orthosis. Hinged AFO was the orthosis that improved the greater number of gait parameters and was the only one to improve velocity with an effect size > 0.8 (large effect). This study shows clinically significant effect of AFO on stride length, ankle dorsiflexion at initial contact and swing phase. Hinged AFO seems to have the greatest effect on gait. New data are needed to refine the choice of the orthosis according to the child gait pattern.

Error tracking control for underactuated overhead cranes against arbitrary initial payload swing angles

This paper exploits an error tracking control method for overhead crane systems for which the error trajectories for the trolley and the payload swing can be pre-specified. The proposed method does not require that the initial payload swing angle remains zero, whereas this requirement is usually assumed in conventional methods. The significant feature of the proposed method is its superior control performance as well as its strong robustness over different or uncertain rope lengths, payload masses, desired positions, initial payload swing angles, and external disturbances. Owing to the same attenuation behavior, the desired error trajectory for the trolley for each traveling distance is not needed to be reset, which is easy to implement in practical applications. By converting the error tracking overhead crane dynamics to the objective system, we obtain the error tracking control law for arbitrary initial payload swing angles. Lyapunov techniques and LaSalle's invariance theorem are utilized to prove the convergence and stability of the closed-loop system. Simulation and experimental results are illustrated to validate the superior performance of the proposed error tracking control method.

An exploratory investigation of changes in gait parameters with age in elderly Japanese women.

BackgroundThe aim of the present study was to identify gait parameters in elderly Japanese women. 30 elderly women (65–74.9 years old) and 19 very elderly women (≥75 years old) participated in this study. A 3-dimensional (3D) motion analysis system was used to collect kinematic data, and a total of 70 gait parameters were analysed. Gait parameters included basic gait parameters, gait cycle parameters, and joints angle parameters, as well as angular velocity parameters, such as peak velocity and timing at the hip, knee, and ankle joints.ResultsOur results indicated that basic gait parameters, such as the gait cycle, peak joint angle timing, and angular velocity parameters, significantly differ between elderly and very elderly women. Delayed peak joint angle timing and angular velocity parameters occurred during critical phases throughout the gait cycle: pre-swing, initial swing, and terminal swing phases.ConclusionsSeveral gait parameters exhibited significant differences between elderly and very elderly women. The timing of the peak joint angle and angular velocity parameters are primary characteristics defining gait changes in the elderly.

Newly Identified Gait Patterns in Patients With Multiple Sclerosis May Be Related to Push-off Quality.

Limited walking ability is an important problem for patients with multiple sclerosis. A better understanding of how gait impairments lead to limited walking ability may help to develop more targeted interventions. Although gait classifications are available in cerebral palsy and stroke, relevant knowledge in MS is scarce. The aims of this study were: (1) to identify distinctive gait patterns in patients with MS based on a combined evaluation of kinematics, gait features, and muscle activity during walking and (2) to determine the clinical relevance of these gait patterns. This was a cross-sectional study of 81 patients with MS of mild-to-moderate severity (Expanded Disability Status Scale [EDSS] median score=3.0, range=1.0-7.0) and an age range of 28 to 69 years. The patients participated in 2-dimensional video gait analysis, with concurrent measurement of surface electromyography and ground reaction forces. A score chart of 73 gait items was used to rate each gait analysis. A single rater performed the scoring. Latent class analysis was used to identify gait classes. Analysis of the 73 gait variables revealed that 9 variables could distinguish 3 clinically meaningful gait classes. The 9 variables were: (1) heel-rise in terminal stance, (2) push-off, (3) clearance in initial swing, (4) plantar-flexion position in mid-swing, (5) pelvic rotation, (6) arm-trunk movement, (7) activity of the gastrocnemius muscle in pre-swing, (8) M-wave, and (9) propulsive force. The EDSS score and gait speed worsened in ascending classes. Most participants had mild-to-moderate limitations in walking ability based on their EDSS scores, and the number of walkers who were severely limited was small. Based on a small set of 9 variables measured with 2-dimensional clinical gait analysis, patients with MS could be divided into 3 different gait classes. The gait variables are suggestive of insufficient ankle push-off.

Changes in Sprint Kinetics and Kinematics Following Static or Dynamic Stretching

Pre-activity stretching is common practice among athletes, yet a lack of consensus exists as to which type of stretch should be performed. Various types of stretching have been utilized over time, though due to equivocal results in the literature, the criterion for choosing a stretch is often based on familiarity or tradition. PURPOSE: This study aimed to compare the effects of dynamic or static stretching on hip kinetics and kinematics during intermittent sprinting. Variables of interest included hip flexion torque production at baseline, post-stretch and post-sprint, hip angular velocity during the initial swing phase of gait, and sprint times throughout the repeated sprint protocol. METHODS: Participants included 10 male (age 25 ± 2.3 years) and 2 female (age 20 ± 1 years) experienced soccer players recruited from the Las Vegas community. Following written informed consent, participants were asked to report to the University of Nevada, Las Vegas Sports Injury Research Center twice. Each visit consisted of the following: 1) 5-minute treadmill warm up at a preferred pace, 2) baseline hip flexion torque measurements, 3) either a static or dynamic stretch, 4) post-stretch torque measurements, 5) a repeated sprint protocol, and 6) post-sprint torque measurements. Peak hip flexion torque values were analyzed in SPSS using a 2x3 repeated measures factorial ANOVA. Paired t-tests for average sprint time, difference between first and last sprint time, peak instantaneous velocity, and percent phase occurrence of peak velocity were computed with (α=0.05). RESULTS: No statistically significant differences were found for any variable among any level. CONCLUSIONS: A lack of statistical significance may be attributed to a low n and high variability among participants. Additionally, coupled with previous results in the literature, it may suggest that there is not a “one-size-fits-all” approach to pre-activity stretching.

Vibration Reduction Using Near Time-Optimal Commands for Systems With Nonzero Initial Conditions

The control of flexible systems has been an active area of research for many years because of its importance to a wide range of applications. The majority of previous research on time-optimal control has concentrated on the rest-to-rest problem. However, there are many cases when flexible systems are not at rest or are subjected to disturbances. This paper presents an approach to design optimal vibration-reducing commands for systems with nonzero initial conditions. The problem is first formulated as an optimal control problem, and the optimal solution is shown to be bang-bang. Once the structure of the optimal command is known, a parametric problem formulation is presented for the computation of the switching times. Solutions are experimentally verified using a portable bridge crane by moving the payload through a commanded motion while removing initial payload swing.

Intralimb Coordination Patterns in Absent, Mild, and Severe Stages of Diabetic Neuropathy: Looking Beyond Kinematic Analysis of Gait Cycle.

AimDiabetes Mellitus progressively leads to impairments in stability and joint motion and might affect coordination patterns, mainly due to neuropathy. This study aims to describe changes in intralimb joint coordination in healthy individuals and patients with absent, mild and, severe stages of neuropathy.MethodsForty-seven diabetic patients were classified into three groups of neuropathic severity by a fuzzy model: 18 without neuropathy (DIAB), 7 with mild neuropathy (MILD), and 22 with moderate to severe neuropathy (SVRE). Thirteen healthy subjects were included as controls (CTRL). Continuous relative phase (CRP) was calculated at each instant of the gait cycle for each pair of lower limb joints. Analysis of Variance compared each frame of the CRP time series and its standard deviation among groups (α = 5%).ResultsFor the ankle-hip CRP, the SVRE group presented increased variability at the propulsion phase and a distinct pattern at the propulsion and initial swing phases compared to the DIAB and CTRL groups. For the ankle-knee CRP, the 3 diabetic groups presented more anti-phase ratios than the CTRL group at the midstance, propulsion, and terminal swing phases, with decreased variability at the early stance phase. For the knee-hip CRP, the MILD group showed more in-phase ratio at the early stance and terminal swing phases and lower variability compared to all other groups. All diabetic groups were more in-phase at early the midstance phase (with lower variability) than the control group.ConclusionThe low variability and coordination differences of the MILD group showed that gait coordination might be altered not only when frank evidence of neuropathy is present, but also when neuropathy is still incipient. The ankle-knee CRP at the initial swing phase showed distinct patterns for groups from all degrees of neuropathic severity and CTRLs. The ankle-hip CRP pattern distinguished the SVRE patients from other diabetic groups, particularly in the transitional phase from stance to swing.

Novel Kinetic Strategies Adopted in Asymmetric Split-Belt Treadmill Walking

ABSTRACTThe hip and ankle strategies that affect learning of a novel gait have not been fully determined, and could be of importance in design of clinical gait interventions. The authors' purpose was to determine the effects of asymmetric split-belt treadmill walking on ankle and hip work during propulsion. Participants were randomized into either a gradual training group or a sudden training group and later returned for a retention test. The gradual training group performed significantly more work at the hip joint of the slow limb during acquisition, and decreased the hip joint work performed during retention. These findings reveal the hip joint on the slow limb during initial swing as a possible site of adaptation to a novel locomotor pattern.

Preferred foot strategy for sprint initiation in children

Research question: Sprinters set their preferred feet on starting blocks. Are there any strategies for children,who have not acquired mature sprint skill in accelerated run, to choose their preferred foot at sprint initiation? Introduction: Laterality and/or limb preference is determined by preferential use of unilateral limb in voluntary movements [1]. Although no significant difference was found in kinematics between preferred and non-preferred foot during gait initiation in adults [2], children seem to choose their motoric behavior dependent on their limbpreference. If so, attaining highhorizontal velocity of whole-body center of mass from 0m/s (i.e., sprint initiation) could be affected by limb preference. The purpose of this studywas to detect the preferred foot strategy on sprint initiation in children. Materials andmethods: Thirty-three children participated (20 boys and 13 girls, age 12.8±1.0 yrs). Lower limb preference was assessed in previous studies [3] (right =21, left = 7). Four trials of 5-m sprint were performed. Sprint timewasmeasuredwith a phototube sensor. Forces and resultant impulses from each foot were calculatedwith force platforms. At start position, participantswere instructed to put one foot on the front platform and the other foot on the rear platform. No other instructions were given during the 1st and 2nd trials. The tester observed their preferential foot placing on the platform and the initial swinging leg. Then, for the 3rd and 4th trials, participants were instructed to replace their front and rear feet on starting position contrary to the 1st and 2nd trials, and the initial swing leg was observed. Front-rear (FR) strategy was defined as participants always using their front or rear legs as the initial swing leg, while right-left (RL) strategy was defined as participants using their preferred limb as the initial swing leg. Results: In the 1st and 2nd trials, 13 out of 33 participants put their right foot on the front and 20 participants set left on the front. Swing initiation from front leg was seen in 20 participants, while the rear leg initiation in 9. There was no significant correlation between limb preference, preferential foot placing, and initiating the swing. For the 3rd and 4th trials, 20 participants changed their initial swinging leg to the opposite side, suggesting FR strategy; while, 2 participants started with the same foot, suggesting RL strategy. The others had no constant strategy of initial swing leg. Sprint times of 3rd and 4th trials were significantly slower than the 1st and 2nd trials (p<0.01). No significant differences in the maximumground reaction force and impulsewere found between trials (0.173=p=0.991). Discussion: The sprint initiation in children is determined by the front-rear strategy rather than the preferred foot strategy.

Development of Stewart platform type ankle-foot device for trip prevention support.

This paper presents an ankle-foot device using a Stewart platform, which is a type of parallel-link mechanism, for trip prevention support. The developed device can reproduce the input motions of the ankle joint in six degrees of freedom by controlling six pneumatic cylinders at the same time. The root mean square errors of the 3-D position and rotation angle of the reproduced motions with the input motions (dorsiflexion and plantar flexion) were 6.3 mm and 3.0°, respectively. Verification experiments for trip prevention support performance were conducted by comparing motions in each walking condition measured using a motion capture system. The experimental results showed that the minimum foot clearance during mid-swing and initial swing increased significantly by the trip prevention support offered by the developed device. The developed device can perform passive exercises for ankle rehabilitation and support walking for trip prevention.

An improved zero vibration method and parameter sensitivity analysis for the swing control of bridge-type grab ship unloader

This paper presents an improved zero vibration method for the swing control of bridge-type grab ship unloader. With the method, the concepts of equivalent frequency and the equivalent damping ratio are proposed to cope with the changeable length of rope, and the optimal path planning is considered to avoid collision and improve efficiency. Numerical simulation results of a case study indicate that the maximum residual swing angle of the grab can be limited to a small range to ensure safety using the improved zero vibration method, whereas the traditional zero vibration method with average frequency and zero damping ratio gets poor results of swing control. After that, the sensitivities of the max residual swing angle to the changes of some main design parameters (damping coefficient, deviation of the center of gravity of the grab in rope direction, and time delay of the system) and operating parameters (position deviation of the trolley, initial length deviation of the rope, and initial swing angle) are analyzed. The results obtained display that the residual swing angle is sensitive to the deviation of grab’s center of gravity, the deviation of trolley’s position, and the initial swing angle under the same control parameters, but insensitive to the damping coefficient, the time delay of the system, and the initial length deviation of the rope. This can help to select the appropriate parameter values ​​or adaptive range in an actual unloader.

Breed-and-burn strategy in a fast reactor with optimized starter fuel

The in situ breed-and-burn (B&B) strategy in fast reactor is capable of offering very high fuel utilization efficiency. CANDLE (Constant Axial shape of Neutron flux, nuclide densities and power shape During Life of Energy) or TWR (Traveling Wave Reactor) is a possible scheme to implement the B&B strategy. The approach in realizing the equilibrium state of CANDLE is based on neutron source supply from ignition zone with enriched uranium or plutonium. And burnable poison is usually employed to compensate the extremely high excess reactivity during the startup. In the present work, the optimization of the starter fuel with only plutonium and depleted uranium is performed to reduce the initial positive excess reactivity swing and to flatten the power distribution. The optimization is done with refer to a nominal steady state CANDLE core. In this regard the swing of the reactivity is limited during the startup. And the initial power shape is flattened significantly compared with that without optimization. It is proved that constructing the ignition zone with refer to the equilibrium state of a CANDLE is effective and feasible to improve the operation performance during the startup.

Alteration in the center of mass trajectory of patients after stroke

Background:The movement disorders due to stroke can alter the motion of the Center of Mass (CoM) of the body. Thus, the analysis of the CoM motion can be an alternative to diagnostic the stroke gait disturbances and has not been widely explored.Objective:To identify and to analyze the alterations of CoM trajectory during both of gait cycles, affected and unaffected, of post-stroke patients comparing to healthy subjects.Methods:The CoM trajectory was obtained using a gold standard method, the three-dimensional (3D) kinematics associate to anthropometry. Two experimental groups were compared: Hemiparetic Group (HG) consisted of fourteen chronic hemiparetic patients and Control Group (CG) by fourteen able-bodied subjects.Results:The statistical analysis (P ≤ 0.05) revealed the following average gait alterations in the HG, in the stance phase of the affected side: higher lateral (midstance), lower vertical (midstance and terminal stance), and lower forward displacement (heel strike until terminal stance). In the swing phase of the affected side, HG showed higher lateral (preswing and initial swing) and vertical displacement (preswing until terminal swing), and lower forward (preswing until terminal swing) displacement of the CoM. There was also anticipation of the instants of maximum displacements in the lateral and vertical directions and lower total range in the forward direction.Conclusion:The CoM trajectory analysis pointed out that the gait after stroke was altered such in the affected as in the unaffected lower limbs, mainly in the single support phase of the affected side, but also in the swing phase of the gait cycle.

Monaural Auditory Cue Affects the Process of Choosing the Initial Swing Leg in Gait Initiation

ABSTRACTThe authors investigated the effect of an auditory cue on the choice of the initial swing leg in gait initiation. Healthy humans initiated a gait in response to a monaural or binaural auditory cue. When the auditory cue was given in the ear ipsilateral to the preferred leg side, the participants consistently initiated their gait with the preferred leg. In the session in which the side of the monaural auditory cue was altered trial by trial randomly, the probability of initiating the gait with the nonpreferred leg increased when the auditory cue was given in the ear contralateral to the preferred leg side. The probability of choosing the nonpreferred leg did not increase significantly when the auditory cue was given in the ear contralateral to the preferred leg side in the session in which the auditory cue was constantly given in the ear contralateral to the preferred leg side. The reaction time of anticipatory postural adjustment was shortened, but the probability of choosing the nonpreferred leg was not significantly increased when the gait was initiated in response to a binaural auditory cue. An auditory cue in the ear contralateral to the preferred leg side weakens the preference for choosing the preferred leg as the initial swing leg in gait initiation when the side of the auditory cue is unpredictable.