본 연구의 목적은 딥 스쿼트 동작 시 발목 관절 유연성이 무릎 관절의 운동역학적 요인들간의 관련성을 분석하는데 있었다. 본 연구는 최근 1년간 하지 근골격계 병력이 없는 성인 남성 19명과 여성 8명이 연구대상자로 참여하였다. 딥 스쿼드 시 발목 관절 유연성과 하지 관절의 운동역학적 요인들과 상관관계를 검증하기 위해 pearson의 적률상관계수(pearson’s correlation coefficient)를 이용하였고(SPSS 24.0, Armonk, NY, USA), 통계적으로 유의미한 상관성을 나타낸 변인들은 단순회기분석(simple regression analysis)을 실시하였으며, 유의 수준은 .05로 설정하였다. 본 연구를 통해 발목 관절 유연성과 무릎 관절의 압력을 결정하는 최대 관절모멘트와 관절반발력 요인들 간의 관련성을 확인할 수 있었다. 그러므로 근력 트레이닝 시 딥 스쿼트와 같은 무릎 관절에 많은 부하를 발생시킬 수 있는 운동을 적용할 때 개인에 신체적 특성 중 발목 관절의 유연성의 정도를 확인하는 것은 신체의 안정성과 무릎 관절의 상해 위험성을 감소시킬 수 있는 운동 강도를 설정하는데 도움이 될 수 있을 것으로 기대한다.

본 연구의 목적은 유도 허벅다리걸기 기술 발휘 시 발목 관절의 테이핑 처치가 하지 관절과 압 력중심(COP, center of pressure)에 미치는 영향을 분석하는데 있었다. 대학 유도 선수 20명(연령, 20.9±0.8세; 신장, 168.6±7.4cm; 체중, 73.5±11.6kg; 신체질량지수, 25.7±2.6kg/m2)이 참여하였으며, 발목 관절 테이핑 처치 전과 후의 2가지 조건에서 허벅다리걸기 기술 발휘 시 지지다리 관절의 각도와 압 력중심 요인을 분석하여 다음의 결과를 도출하였다. E2(t=2.411, p=.027) E4(t=2.388, p=.029)시점에서 발목 관절의 각도는 테이핑 처지 전에 비해 처치 후 발목의 각도가 통계적으로 적은 수치를 나타내었고, E2(t=-2.343, p=.032) E3(t=-4.531, p=.000)시점에서 힙 관절의 각도는 통계적으로 크게 나타났다. 그리 고 발목 관절 테이핑 처치 후 좌·우의 COP 이동은 상대를 메치는 P3 국면에서 통계적으로 크게 나타났으 며(t=2.670, p=.016), 전·후의 COP 이동은 상대의 무게 중심을 기울이는 P1 국면에서 통계적으로 적은 수 치를 나타내었다(t=2.846, p=.011). 그러므로 허벅다리걸기를 특기로 사용하는 유도 선수들은 발목 관절 테이핑으로 인해 발생하는 지지관절의 운동 기능과 COP의 이동범위를 고려하여 사용하는 것에 대하여 제 안하고자 한다.

Background: Ankle instability usually occurs after stroke, and contributes to unsafe walking and associated risk of falling in the affected patients. Objective: To investigate the effects of kinesiology taping (KT) on gait and balance ability (center of pressure, CoP) in patients with ankle instability after stroke. Design: One group, pre-post design. Methods: A total of 11 patients with ankle instability after stroke were enrolled. In all subjects, the gait and balance ability were assessed under 2 conditions: KT and barefoot. Gait and balance ability was assessed using GAITRite system and FDM-S platform. Results: Comparison between KT and barefoot condition, KT condition was significantly higher in velocity, cadence, step length, and stride length than barefoot condition (P<.05). KT condition was significantly lower in CoP path length and sway speed than barefoot condition (P<.05). Conclusion: KT indicated potential as a helpful method for walking and balancing ability in patients with ankle instability after stroke. Therefore, this study recommends KT as an option applicable to the stroke with ankle instability.

Background: Stroke patients have leg muscle weakness and impaired balance resulting in compensatory changes. To restore balance in these patients, functional training using postural strategy is needed. Objective: To examine the effects of ankle and hip strategy training on the center of pressure (COP) movement and limits of stability (LOS) in standing posture in stroke patients. Design: The study was an assessor-blinded and randomized-controlled clinical trial. Methods: Thirty patients were randomly assigned to an ankle strategy training group and a ankle/ hip strategy training group. Patients in the ankle strategy training group underwent ankle strategy exercise for 30 min, and those in the ankle/ hip strategy training group underwent 15 min of ankle strategy exercise and 15 min of hip strategy exercise. Both groups underwent training thrice a week for four weeks. Forward, backward, paretic side, and non-paretic side COP movements and LOS were measured using BioRescue. Results: After the intervention, except for the backward area in the ankle strategy training group, the COP movement area and the LOS were significantly improved in both the groups. In addition, these improvements were significantly higher in ankle/ hip strategy training group than that in the ankle strategy training group. Conclusions: Ankle strategy training in addition to hip strategy training improves COP movement (forward-backward, paretic side area, and nonparetic side area) and LOS in stroke patients.

Background: Ankle evertor muscles are important for preventing lateral ankle sprain. Since, the evertor muscles cross the ankle and toe joints, the position at which the ankle evertor muscle strength is measured is important. However, no studies have previously investigated the effect of ankle and toe positions on the strength of the ankle evertor muscle. Objects: This study is aimed to determine the effect of various ankle and toe joint positions on the strength of the ankle evertor muscles in healthy subjects. Methods: Eighteen healthy subjects participated in this study. Isometric ankle evertor strength of the dominant leg was determined in each subject in different ankle and toe positions (dorsiflexion (DF) with toe extension (TE), DF with toe flexion (TF), plantar flexion (PF) with TE, and PF with TF). A 2 by 2 repeated analysis of variance (ANOVA) was used to determine the difference in the evertor strength between the ankle positions (PF and DF) and toe positions (TE and TF). Results: The results indicate that there was no significant ankle position by toe position interaction effect (p=.83). However, the ankle evertor strength was significantly increased in the ankle DF position than in the PF position (p<.01), and the ankle evertor strength during eversion with TE was significantly higher than eversion with TF (p<.01). Conclusion: The findings of this study suggest that clinicians should consider the ankle and toe positions when measuring the muscle strength and during performance of selective muscle strengthening exercises of the ankle evertor muscles.

Background: Measurement of passive ankle dorsiflexion range of motion (ADROM) is often part of a physical therapy assessment. Objects: The objective of this study was to identify the effects of subtalar joint neutral position (SJNP) on passive ADROM according to knee position in young adults. Methods: We recruited 14 young adult participants for this study. Two examiners used a universal goniometer to measure passive ADROM with and without SJNP. Dorsiflexion force was applied to the forefoot until maximum resistance was reached in two knee positions (extension and 90˚ flexion) in the prone position. Subtalar joint position was also recorded at maximum ADROM. Passive ADROM was measured three times at different knee and subtalar joint positions, in random order. Two-way repeated-measures analysis of variance was used to compare the effects of subtalar joint and knee position on passive ADROM. Results: Passive ADROM was significantly lower with than without SJNP during both knee extension (mean difference: 7.4˚) and 90˚ flexion (mean difference: 16.9˚) (p<.01). Passive ADROM was significantly higher during 90˚ knee flexion than during knee extension both with (mean difference: 5.8˚) and without SJNP (mean difference: 15.2˚) (p<.01). The valgus position of the subtalar joint was significantly lower with than without SJNP during both knee extension (mean difference: 3.3˚) and 90˚ flexion (mean difference: 4.3˚) (p<.01). Conclusion: Our results indicate that the gastrocnemius may limit ankle dorsiflexion more than the soleus does. Greater dorsiflexion at the subtalar and midtarsal joints was observed during passive ADROM measurement without than that with SJNP; therefore, SJNP should be maintained for accurate measurement of ADROM.

Background: Vibration exercise after ankle surgery improves proprioception and ankle muscle strength through vibration stimulation. Objective: To examine the effects of vibration exercise on the ankle stability. Design: Randomized controlled clinical trial (single blind) Methods: Twenty soccer players were randomly divided into experimental group and control group. The Vibration exercise program was conducted 12 weeks and 3 times a week. Ankle joint proprioceptive sensory test and Isokinetic muscle strength test were performed using Biodex system pro Ⅲ to measure plantar flexion / dorsiflexion and eversion / inversion motion. Results: The result of isokinetic test of ankle joint is showed significant improvement in all measurement items, such as leg flexion, lateral flexion, external and internal muscle forces, compared to previous ones by performing vibration movements for 12 weeks. However, in the comparison group, plantar flexor (30°), eversion muscle (120°), inversion (30°) of limb muscle strength were significantly improvedcompared with the previous phase; was no significant difference in dorsi-flexion. There was no significant difference between groups in all the items. Conclusions: In this study, we analyzed the effects of rehabilitation exercise on soccer players who had reconstructed with an ankle joint ligament injury through vibration exercise device. As a result, we could propose an effective exercise method to improve the ability, and confirmed the applicability as an appropriate exercise program to prevent ankle injuries and help quick return.

Background: Functional ankle instability (FAI) indicating a decrease in muscle strength, proprioception, neuromuscular control, balance and postural control function. Objective: To investigate the effect of jumping exercise on the supporting surface on the ankle muscle thickness, proprioceptive sensation, and balance in adults with FAI. Design: Randomized Controlled Trial. Methods: Twenty young people with FAI were randomly assigned to the unstable supporting surface jump group (N=10) and the stable supporting surface jump group (N=10). The intervention was conducted three times a week for eight weeks, and for 30 minutes per session. Trampoline was used as an unstable support surface and the stable support surface was carried out on a regular floor. The thickness of the tibialis anterior muscle and medial gastrocnemius muscle was measured by ultrasonography, and the proprioception of dorsiflexion and plantarflexion was measured using an electrogoniometer. The dynamic balance was also measured with a balance meter. Results: The the muscle thickness of the medial gastrocnemius muscle was significantly higher in the stable supporting surface jump group than in the unstable supporting surface jump group (p<.05). Furthermore, the plantar flexion proprioception and dynamic balance were significantly improved in the unstable supporting surface jump group than in the stable supporting surface jump group in the intergroup comparison (p<.05). Conclusions: The conclusion has been reached in this study that the jumping exercise on the unstable supporting surface could be a more effective in improving FAI than the regular surface.

The purpose of this study was to assess the changes in balance and proprioception of adults with limited ankle joint dorsiflexion, after the application of talocrural joint mobilization. The subjects of this study included 23 college students in their twenties with limited ankle joint dorsiflexion. The students were randomly assigned to the ankle joint mobilization group (AJMG, n=12) and the control group (CG, n=11). After 2 weeks of intervention using grade III talocrural joint mobilization in the anterior-posterior movement, the balance and proprioception of the subjects were assessed. Static/dynamic balance capabilities and ankle proprioception were analyzed using paired t-test and independent t-test. The dynamic balance and proprioception of AJMG were significantly improved after intervention (p<.05), In the comparison between the groups after the intervention, the dynamic balance and proprioceptive sense of AJMG were significantly improved compared to the control group (p<.05). This study suggests that AJMG can help improve the dynamic balance and proprioception.

The purpose of this study was to identify the effect of proprioceptive neuromuscular facilitation (PNF) stretching exercise and joint mobilization on ankle joint range of motion (ROM), plantar pressure, and balance in subjects with stroke. Thirty patients (n=30) were organized into three groups, each of which received different treatments: PNF stretching (n=10), joint mobilization (n=10), and joint mobilization and PNF stretching combined (n=10). Each group received three exercise sessions per week for four weeks. The ankle ROM was measured using a goniometer, and plantar pressure and balance ability were measured using BioResque static posturography. In comparison within each group, the joint mobilization group and the joint mobilization with PNF stretching group showed significant improvements in ankle ROM, plantar pressure, and balance ability (p<.05). In comparison between the groups, a statistically significant difference was found in SECS change between the PNF stretching group, joint mobilization group and the joint mobilization with PNF stretching group. This study found demonstrates that the joint mobilization and joint mobilization with the PNF stretching methods were effective in improving ankle ROM, plantar pressure, and balance ability in stroke patients.

The purpose of this study was to investigate the effects of sling exercise on muscle activity and balance on football players with chronic ankle instability. Eight subjects performed Biodex and sling exercises for four weeks and compared the muscle activity and balance ability of the uninjured and injured feet. Stable and unstable foot % MVIC did not change significantly after treatment in all muscles. The total balance ability was not significantly different between the two groups, however, increased only in the unstable side. The anterior/posterior balance ability also represented no significant difference between the groups and was significantly improved only in the unstable side. The medial/lateral balance ability was not significantly different between the groups and was significantly improved only in the unstable side. This study suggests that sling exercise contributes to improving % MVIC, total balance ability, anterior/ posterior balance ability, and medial/lateral balance ability of the unstable side.

It has been reported that gastrocnemius tightness and posterior talar glide are crucial factors influencing ankle dorsiflexion. However, the relationship of ankle dorsiflexion and these factors is not identified in previous studies. The purpose of this study was to identify the relationship of ankle dorsiflexion passive range of motion and gastrocnemius tightness and posterior talar glide. Twenty-five male subjects participated in this study. Bilateral weight-bearing ankle dorsiflexion passive range of motion and amount posterior talar glide of participants were measured using an inclinometer. Change in myotendinous junction of medial gastrocnemius was measured using ultrasonography to identify gastrocnemius tightness. Pearson product moment correlations were performed to examine correlations between ankle dorsiflexion passive range of motion and gastrocnemius tightness and posterior talar glide. Present findings revealed significant correlation between ankle dorsiflexion passive range of motion and gastrocnemius tightness (p=0.017, r=0.336). Also, ankle dorsiflexion passive range of motion was correlated with posterior talar glide (p=0.001, r=0.470). The present findings provide experimental evidence for factors influencing weight-bearing ankle dorsiflexion.

The purpose of the study was to investigate the immediate effects of negative pressure soft tissue therapy on muscle tone, muscle stiffness and balance in patients with stroke. In total, 20 patients with stroke and assigned to the negative pressure soft tissue therapy group (NPST, n=10) or, placebo-negative pressure soft tissue therapy group(Placebo-NPST, n=10). Both groups underwent NPST or placebo-NPST once a day during the experimental period. MyotonPRO was used to assess the parameters for muscle tone and stiffness. Biorescue was used to assess the parameters for balance. Each group showed improvements in muscle tone, muscle stiffness, and balance ability (p<.05). Especially, Muscle tone, muscle stiffness, and anterior length in the limit of stability were the significant improvement on NPST group (p<.05). The results of the study suggest that the NPST is effective in improving muscle tone, muscle stiffness, and balance ability in patients with stroke.

This study was conducted to observe the isokinetic strength (IS) of the hip, ankle, and knee joints in young age groups. Thirty eight men and thirty one women with mean age of 30.4 ± 3.5 and 32.8 ± 4.4 years, respectively, were enrolled in this study. Measurements of hip flexion, extension, abduction, and adduction at 30° / sec, Knee flexion and extension at 60° / sec, ankle inversion, eversion, plantarflexion, and dorsiflexion 30° / sec were conducted. Absolute IS (Nm), relative IS (Nm/kg), strength ratios, correlations between movements were observed. Significant differences in absolute and relative strength were observed between groups in all movement except in the relative ankle strength. Relative isokinetic strength ratios of hip flexion/extension were .45 and .55, knee flexion/extension were .84 and .89, ankle dorsi/plantarflexion were .30 and .29, and ankle eversion/inversion were .86 and .84 for men and women, respectively. In the hip extension, men had about three times the body weight ,and women had about 2.5 times the strength. The abduction muscle had about 1.5 times the body weight of both men and women. Height and body weight showed the significantly strong correlating relationship with hip (r, .76-.86) and knee (r, .67-.84) strength. However, ankle strength showed the comparatively correlating relationship, especially in women (r, .03 - .36). Similar age and physique characteristics of female and male groups could provide useful isokinetic strength reference values for developing the exercise program for healthy and rehabilitation groups.

The purpose of this study was to investigate the effect of heel off stairway walking exercise on the increase of muscle activity and balance activity of the ankle joint muscles in university students with functional ankle instability. The conservative treatment for the control group consisted of stairway walking (n=10) and the experimental group consisted of heel off stairway walking (n=11). The therapeutic intervention of the control and experimental groups was performed a total of 12 exercise sessions, 3 times per week for 4 weeks. To compare the two groups, the level of ankle disability was assessed by using the EMG, BT4 and Pedoscan in pre-treatment and post-treatment. Muscle activity increased in both the experimental groups and control groups in each group, however there was no significant difference between the groups. Balance ability did not show any significant difference. This study demonstrates that heel-off stairway walking is effective in significantly increasing muscle activity, however did not significantly improve balance ability.

The purpose of this study was to investigate the effect of fall injuries on the balancing abilities and ankle flexibility. Fifteen of the voluntary participants had no experience of falling in the last two years (none falling group, NFG) and 15 others experienced at least one (falling group, FG). Static balance (sway length, sway area), dynamic balance (timed up and go (TUG), and functional to reach test (FRT) were measured in each group. In comparison of static balance, sway length was not significantly different between NFG and FG in both eyes open and eyes close, however the sway area of the FG was significantly wider than that of the NFG (p<.05). In dynamic balance comparisons, TUG of FG was significantly longer than that of NFG (p <.05), however FRT and STS were no significant difference between groups. Ankle flexibility was significantly higher in NFG than in FG. This study suggests that the fall prevention program should include methods for improving ankle stability and lower extremity function.

Background: The MLA is supported by both the abductor hallucis (ABH) and the extrinsic muscles. Insufficient muscular support may lower the MLA when the body’s weight is applied to the foot. The short foot exercise (SFE) is effective in increasing the height of the MLA for people with flat feet. Most of the research related to the SFE has simply evaluated the efficiency of the exercise using enhanced ABH electromyography (EMG) activation. Since the tibialis anterior (TA), peroneus longus (PER), and ABH are all involved in supporting the MLA, a new experiment design examining the EMG of the selected muscles during SFE should be applied to clarify its effect. Objects: Therefore, this study aimed to clarify the effect of the SFE in different ankle position on the MLA angle and the activation of both the intrinsic and extrinsic muscles and to determine the optimal position. Methods: 20 healthy subjects and 12 subjects with flat feet were recruited from Yonsei University. The surface EMG and camera were used to collect muscle activation amplitude of TA, PER, and ABH and to capture the image of MLA angle during SFE. The subjects performed the SFE while sitting in three different ankle positions—neutral (N), dorsiflexion (DF) at 30 degrees, and plantar flexion (PF) at 30 degrees. Results: ABH EMG amplitudes were significantly greater in N and DF than in PF (p<.05). Muscle activation ratio of TA to ABH was the lowest in PF (p<.05). MLA angle in both groups significantly decreased in PF (p<.01). The TA and ABH was activated at the highest level in DF. However, in PF, subjects significantly activated the ABH and PER with relatively low activation of TA. Conclusion: Therefore, researchers need to discuss which SFE condition most effectively use the arch support muscle for flat foot.

The purpose of this study was to investigate the complex ankle exercises on balance. 22 participants (male: 14, female: 8) with functional ankle instability were participated. Functional ankle instability was selected to be less than 24 points using the Cumberland ankle instability tool (CAIT) with people who had severe ankle sprain and then experiencing ankle giving way. A total of 20 minutes performed three times a week for four weeks with muscle strength and balance exercises. Muscle strengthening exercise was performed with Theraband, and balance exercise was performed with unstable support plates. Biodex balance systemⓇ was used to measure static and dynamic balance. The dynamic balance was selected in grade 2, 4, and 8. The static and dynamic balance (grade: 2, 4,and 8) balance was significantly decreased in anterior-posterior, and medial-lateral directions (p<.05). The instability was significantly increased after exercise (p<.05). These results suggest that complex exercises are beneficial to decreasing the functional ankle instability.

Background: The multiple hop test is an active performance test that has been commonly used to assess individuals with functional ankle instability. Previous studies have suggested that insufficiency of dynamic postural stability and passive stability during dynamic activities can have an influence on performance in the multiple hop test. However, no study has investigated the effects of dynamic postural stability training and ankle bracing on multiple hop test performance in individuals with functional ankle instability. Objects: The purpose of this study was to compare the immediate effects of dynamic postural stability training versus ankle bracing in the performance of the multiple hop test for participants with functional ankle instability. Methods: Twenty-nine participants with functional ankle instability who scored below 24 in the Cumberland Ankle Instability Tool were selected. The participants were randomly divided into two groups: a dynamic postural stability training group (n1=14) and an ankle bracing control group (n2=15). The multiple hop tests were performed before and after applying each intervention. Dynamic postural stability training was performed using visual-feedback-based balance-training equipment; participants in this group were asked to perform a heel raise in a standing position while watching the centering of their forefoot pressure to prevent excessive ankle inversion. Ankle bracing was applied in the control group. Results: When comparing the pre- and post-intervention period for both groups, both methods significantly improved the results of the multiple hop test (p<.05). However, no significant differences were shown between the dynamic postural stability training and ankle bracing groups (p>.05). Conclusion: Both dynamic postural stability training and ankle bracing showed significant improvement (2.85 seconds and 2.05 seconds, respectively) in test performance. Further study is needed to determine the long-term effects of dynamic postural stability training and to determine whether insufficient dynamic postural stability is a causative factor for functional ankle instability.

The purpose of this study was to investigate the effects of combined wedge on the range of motion in ankle and knee joint, ankle eversion moment and knee adduction moment, and center of pressure excursion of foot for genu varus among adult men during gait. This study was carried out with 10 adult men for genu varus in a motion analysis laboratory in J university. The subjects of the experiment were measured above 5cm width between the knees on contact of both medial malleolus of ankle while standing. The width of their knees in neutral position was measured without the inversion or eversion of the subtalar joint by the investigator. The subjects of the experiment were ten who were conducted randomly for standard insole, insole with 10° lateral on rear foot wedge, insole at 10°lateral on rear foot and 5° medial on fore foot wedge. Before and after intervention, changes on the range of motion in ankle and knee joint, ankle eversion moment and knee adduction moment, and center of pressure excursion were measured. In order to compare analyses among groups; repeated one-way ANOVA and Scheffé post hoc test were used. As a result, combined wedge group was significantly decreased compared to control wedge group in terms of knee varus angle in mid-stance(p<.05). Combined wedge group was significantly decreased compared to lateral wedge group in terms of ankle eversion moment in whole stance(p<.05). Combined wedge group was significantly decreased compared to lateral wedge group in terms of knee adduction moment in whole stance(p<.05). Combined wedge group was significantly decreased compared to lateral wedge in terms of center of pressure excursion in whole stance(p<.05). The results of this study suggest that combined wedge for genu varus decreased ankle eversion moment and knee adduction moment upon center of pressure excursion. We hypothesize that combined wedge may also be effective in the protection excessive ankle pronation.