Ji-Yeon Yoon

Differences in activities of the lower extremity muscles with and without heel contact during stair ascent by young women wearing high-heeled shoes

BackgroundThe purpose of this study was to identify any differences in the activity patterns of lower extremity muscles with and without heel contact during stair ascent by women in their twenties wearing high-heeled shoes.MethodsTwenty healthy female subjects wearing high-heeled shoes walked up a step with a height of 20 cm with and without heel contact, during which the activities of the vastus medialis oblique, vastus lateralis, and gastrocnemius were recorded using surface electromyography.ResultsDuring stair ascent the activities of the vastus lateralis and vastus medialis oblique were significantly higher and that of the gastrocnemius significantly lower with high-heel contact than without high-heel contact.ConclusionWe suggest that young women wearing high-heeled shoes should step up with heel contact on the stair surface during stair ascent to activate the quadriceps muscle.

Changes in kinetic, kinematic, and temporal parameters of walking in people with limited ankle dorsiflexion: pre-post application of modified mobilization with movement using talus glide taping.

OBJECTIVE The purpose of this study was to investigate the changes in passive ankle dorsiflexion range of motion (ROM), maximum plantar force, force-time integral, and time to heel off during walking between pre- and postapplication of modified mobilization with movement (MWM) using talus glide taping in people with limited ankle dorsiflexion. METHODS Eighteen feet with limited ankle dorsiflexion in 13 people were examined. Participants performed 3 different walking tasks in the following order: walking before and immediately after applying the modified MWM using talus glide taping and walking after 5-minute walking with the modified MWM using talus glide taping. A floor-mat pressure measurement system (HR-mat) was used to measure maximum plantar force, force-time integral, and time to heel off; and passive ankle dorsiflexion ROM was measured using a standard goniometer. The significance of differences was assessed using repeated one-way analysis of variance. RESULTS Passive ankle dorsiflexion ROM and time to heel off were significantly increased after 5-minute walking with the modified MWM using talus glide taping compared with walking before and immediately after applying the tape. Significantly increased maximum plantar force and force-time integral on the hindfoot and significantly decreased force-time integral on the forefoot during walking after 5-minute walking were observed with the modified MWM using talus glide taping compared with before applying the tape. No significant difference between before and immediately after applying the tape was observed in any variable. CONCLUSIONS Our results suggest that walking an additional 5-minute with the modified MWM using talus glide taping increased passive ankle dorsiflexion ROM and time to heel off and improved dynamic plantar loading during walking.

Plantarflexor and Dorsiflexor Activation during Inclined Walking with and without Modified Mobilization with Movement Using Tape in Women with Limited Ankle Dorsiflexion

[Purpose] This study compared the EMG activities of the plantarflexor and dorsiflexor muscles during inclined walking with and without modified mobilization with movement (modified MWM) using tape in women with limited ankle dorsiflexion. [Subjects] Fifteen women with limited dorsiflexion in their feet (22 feet in total) were recruited for this study. [Methods] The subjects walked with and without modified MWM using tape on a treadmill at 6 degrees with a speed of 1.25 m/s for 5 minutes. The EMG activities of the medial gastrocnemius (GCM) and tibialis anterior (TA) muscles were measured using a surface EMG system. [Results] During incline walking with modified MWM using tape, the mean EMG activity of the GCM significantly increased, and that of the TA decreased between heel strike and heel off. There was no difference between heel off and toe off in the two muscles. [Conclusions] Modified MWM using tape on the talus during incline walking could alter the muscle activities of the GCM and TA between heel strike and heel off in women with limited ankle dorsiflexion.

Effect of initial position on the muscle activity of the hip extensors and amount of pelvic tilt during prone hip extension

[Purpose] The aim of this study was to identify the effects of initial position of the hip joint with changes in the hip joint angle on the respective muscle activities of the bilateral erector spinae (ES), unilateral gluteus maximus (GM), and biceps femoris (BF) and the amount of pelvic anterior tilt during prone hip extension (PHE). [Subjects] Fifteen healthy volunteers were enrolled in this study. [Methods] The subjects performed PHE in three positions: neutral, 20°, and 45° flexed hip joint. The activities of the ES, GM, and BF were measured using surface electromyography, and kinematic values for pelvic anterior tilt were calculated using a motion capture system. [Results] There was a significant decrease in muscle activity of the contralateral ES at 45°, and an increase in the GM muscle activity and decrease in the BF muscle activity at 20°. The amount of pelvic anterior tilt was lower at 20°. [Conclusion] These results suggest that a hip flexion position of 20° would have an advantage over the other measured positions.

The effects of an exercise with a stick on the lumbar spine and hip movement patterns during forward bending in patients with lumbar flexion syndrome

BACKGROUND AND OBJECTIVE Forward bending is frequently performed in daily activities. However, excessive lumbar flexion during forward bending has been reported as a risk factor for low back pain. Therefore, we examined the effects of an exercise strategy using a stick on the angular displacement and movement onset of lumbar and hip flexion during forward-bending exercises in patients with lumbar flexion syndrome. METHODS Eighteen volunteers with lumbar flexion syndrome were recruited in this study. Subjects performed forward-bending exercises with and without a straight stick in standing. The angular displacement and movement onset of lumbar and hip flexion during forward-bending exercises were measured by using a three dimensional motion analysis system. The significances of differences between the two conditions (with stick vs. without stick) was assessed using a one-way repeated analysis of variance. RESULTS When using a stick during a forward-bending exercise, the peak angular displacement of lumbar flexion decreased significantly, and those of right and left-hip flexion increased significantly compared with those without a stick. The movement onset of lumbar flexion occurred significantly later, and the onset of right-hip flexion occurred significantly earlier with than without a stick. CONCLUSIONS Based on these findings, a stick exercise was an effective method to prevent excessive lumbar flexion and more helpful in developing hip flexion during a forward-bending exercise. These findings will be useful for clinicians to teach self-exercise during forward bending in patients with lumbar flexion syndrome.

Three-Dimensional Analysis of Foot Motion After Uphill Walking With Mobilization With Movement Using Tape Applied to the Talocrural Joint in Women With Limited Ankle Dorsiflexion

Background: Previous studies that investigated mobilization with movement (MWM) treatment assessed only improvements in passive range of motion (ROM). No information is currently available regarding the efficacy of modified MWM by application of tape. Therefore, we investigated the effect of uphill walking with modified MWM using tape applied to the talocrural joint (uphill walking with MWM taping) in women with limited ankle dorsiflexion. Methods: Twelve feet of 12 women with ankle dorsiflexion < 8 degrees were studied. Passive ROM measured using a goniometer was used to select participants. Participants walked on a level walkway under 3 conditions: before exercise, after uphill walking, and after uphill walking with MWM taping. The Oxford Foot Model using 3D motion analysis system was used to examine dynamic foot kinematics, and statistical significance was determined by 1-way repeated-measures analysis of variance. Results: After uphill walking with MWM taping, peak hindfoot dorsiflexion relative to the tibia was significantly greater than that before exercise and after uphill walking. Furthermore, peak forefoot plantarflexion relative to the hindfoot, peak hindfoot plantarflexion relative to the tibia, and backward tilt of the tibia were greater than those before exercise. Conclusions: Uphill walking with MWM taping resulted in an immediate alteration in foot motion during walking, increasing hindfoot dorsiflexion in particular. Clinical Relevance: Further studies are needed to investigate the long-term effects of uphill walking with MWM taping and its potential use in rehabilitation training.