[Show abstract][Hide abstract] ABSTRACT: Tightness of the iliotibial band (ITB) has been documented as a major factor in lateral patellar translation because the ITB inserts into the lateral border of the patella through the iliopatellar band. The aim of this study was to compare the patella-condyle distance (PCD) between subjects with and without ITB tightness. We also investigated the relationship between ITB length and lateral patellar translation in hip adduction.
[Show abstract][Hide abstract] ABSTRACT: Objective
to compare the effects of pulsed electromagnetic field (PEMF) therapy and sham treatment on DOMS-related variables in elbow flexors at 24, 48 and 72 hours after delayed onset muscle soreness (DOMS) induction exercise.
randomized, double-blind, placebo-controlled study.
Yonsei University laboratory.
In total, 30 healthy male college students Main outcome measures: Muscle soreness, peak torque, median frequency (MDF) and electromechanical delay (EMD) during isometric contraction at 24, 48 and 72 hours after DOMS induction exercise.
Overall, the application of the PEMF was found to be effective in reducing the physiological deficits associated with DOMS, including improved recovery of perceived muscle soreness, MDF, and EMD during isometric contraction. Our results did not show that PEMF treatment was mechanically more effective in isometric peak torque generation compared to the sham group.
this study indicates that PEMF may be useful as a modality to reduce DOMS symptoms. However, further well-designed experiments are required to determine optimal treatment dosage and duration, and to investigate the physiological and clinical mechanisms of PEMF on DOMS.
Physical Therapy in Sport 01/2014; · 1.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The direction of fiber alignment within a muscle is known to influence the effectiveness of muscle contraction. However, most of the commonly used clinical gluteus maximus (GM) exercises do not consider the direction of fiber alignment within the muscle. Therefore, the purpose of this study was to investigate the influence of hip abduction position on the EMG (electromyography) amplitude and onset time of the GM and hamstrings (HAM) during prone hip extension with knee flexion (PHEKF) exercise. Surface EMG signals were recorded from the GM and HAM during PHEKF exercise in three hip abduction positions: 0°, 15°, and 30°. Thirty healthy subjects voluntarily participated in this study. The results show that GM EMG amplitude was greatest in the 30° hip abduction position, followed by 15° and then 0° hip abduction during PHEKF exercise. On the other hand, the HAM EMG amplitude at 0° hip abduction was significantly greater than at 15° and 30° hip abduction. Additionally, GM EMG onset firing was delayed relative to that of the HAM at 0° hip abduction. On the contrary, the GM EMG onset occurred earlier than the HAM in the 15° and 30° hip abduction positions. These findings indicate that performing PHEKF exercise in the 30° hip abduction position may be recommended as an effective way to facilitate the GM muscle activity and advance the firing time of the GM muscle in asymptomatic individuals. This finding provides preliminary evidence that GM EMG amplitude and onset time can be modified by the degree of hip abduction.
[Show abstract][Hide abstract] ABSTRACT: Delayed onset muscle soreness (DOMS) is a painful condition that arises from exercise-induced muscle damage after unaccustomed physical activities. Various therapeutic interventions have been applied to reduce the intensity and duration of DOMS-related symptoms. Recently, pulsed electromagnetic field (PEMF) intervention has been introduced as an alternative noninvasive treatment for DOMS. This randomized, double-blind, placebo-controlled experiment was conducted to examine the effects of PEMF therapy on DOMS in elbow flexors at 24, 48, and 72 hours after the experimental DOMS induction. Thirty healthy volunteers ( yrs, cm, and kg) participated in this study. Each was randomly assigned to a PEMF or placebo group. On the first day, DOMS was induced in the elbow flexors by repeated isokinetic motions at low () and fast () speeds in all subjects. Thereafter, the PEMF group received 15-min daily treatment with a PEMF device. The placebo group received sham treatment of the same duration. Overall, PEMF application was more effective than the sham treatment in reducing the physiological symptoms associated with the DOMS including perceived soreness, median frequency, and electromechanical delay of the surface electromyography. In addition, median frequency and isokinetic peak torque of the PEMF group recovered to the pre-DOMS induction level earlier than the placebo group. In conclusion, this study suggests that PEMF can be applied as a new recovery strategy in reducing DOMS symptoms. Further experiments are required to examine the effect of the PEMF treatment on different types of exercise conditions and to determine the optimal treatment dosage and duration in a real clinical setting.
[Show abstract][Hide abstract] ABSTRACT: The smart-phone has become a necessity for most people. In this study, we determined that using a smart-phone for 20 minutes can cause increased neck and shoulder muscle activities and fatigue. Seventeen healthy male smart-phone users who attended Yonsei University played a smart-phone game for 20 minutes and changes in their bilateral cervical erector spinae and upper trapezius muscle activities and fatigue were measured. To assess muscle activities and fatigue, we used the following variables: the median frequency, the 50th percentile Amplitude probability distribution function (APDF) value (median load), and the discrepancy in the 90th percentile APDF value and the 10th percentile APDF value (APDF range). A paired t-test was used to compare pre-smart-phone-use status with post-smart-phone-use-status. The median frequency of the bilateral cervical erector spinae and the upper trapezius decreased significantly after 20 minutes of smart-phone use (p
[Show abstract][Hide abstract] ABSTRACT: We evaluated whether group locomotor imagery training-combined knowledge of performance (KP) lead to improvements in gait function in community dwelling individuals with chronic stroke. Ten adults who had suffered a hemiparetic stroke at least 6 months earlier participated in group locomotor imagery training-combined KP for 5 weeks, twice per week, with 2 h intensive training. Dynamic gait index scores increased significantly after the group locomotor imagery training-combined KP. However, times for the timed up-and-go test did not improve significantly after the training. Group locomotor imagery training-combined KP may be a useful option for the relearning of gait performance for community dwelling individuals with chronic hemiparetic stroke.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: This study examined the effects of ankle and knee joint immobilization on postural control in healthy young adults while standing. METHODS: The 24 participants included in this study participated in postural standing tests under four different constraint conditions: free joints, ankle immobilization only, knee immobilization only, and ankle-knee immobilization. Tests were performed using a commercial balancing equipment (Biodex(TM), Inc., NY, USA) and software. RESULTS: The overall limit-of-stability score and duration to completion of task were obtained at 75% limit-of-stability (moderate level of difficulty). The overall limit-of-stability score of free joints (34.5±9.1) were significantly different with the ankle immobilization only (26.0±11.6), and ankle-knee immobilization (26.4±7.4) conditions. The test duration increased in the following order: free joints (57.8±10.9), knee immobilization only (62.5±14.0), ankle immobilization only (68.0±14.9), and ankle-knee immobilization (69.4±17.7). The duration of the free joint condition greatly decreased than ankle immobilization only and ankle-knee immobilization conditions. CONCLUSIONS: The ankle and knee joints have sufficient range of motion to prevent falls related to decrease postural stability due to insufficient range of motion or to improve postural stability.
[Show abstract][Hide abstract] ABSTRACT: As a means of external stabilization of the sacroiliac joint (SIJ), many clinicians have often advocated the use of the pelvic compression belt (PCB). The objective of this pilot study was to compare the effects of the PCB on hip extensor muscle activation patterns during one-leg standing in subjects with and without sacroiliac joint pain (SIJP). Sixteen subjects with SIJP and fifteen asymptomatic volunteers participated in this study. Surface electromyography (EMG) data [signal amplitude and premotor reaction time (RT)] were collected from the gluteus maximus and biceps femoris muscles of the supporting leg during one-leg standing with and without the PCB. Compared to that of the asymptomatic individuals, the EMG amplitude of the biceps femoris was significantly decreased in individuals with SIJP upon the application of the PCB (p < 0.05). Furthermore, on using the PCB, in individuals with SIJP, the RT of the gluteus maximus was significantly decreased; however, the RT of the biceps femoris was increased (p < 0.05). Thus, our data support the use of the PCB to modify the activation patterns of the hip extensors among patients with SIJP.
[Show abstract][Hide abstract] ABSTRACT: The present study highlighted a novel motor point location index (MPLI) for the precise localization of the motor point (MP) of the tibialis anterior (TA) using a regression equation.
Twenty healthy young adults (female=8; mean age ± SD=18.50 ± 0.32) were volunteered for this study. The regression analysis was performed by correlating the MP locations with anatomical landmarks. The TA muscle's MP location was bilaterally determined by needle electromyography (EMG) measurement. The anatomical landmarks included lower leg length (LLL), tibial tuberosity-intermalleolar line length (TT-ILL), the knee width (KW) and the leg width (LW).
The excellent correlation between the TT-ILL and the vertical MP location was obtained, R(2) 0.815. Approximately 82% of the variance of the vertical MP location was accounted for by its linear relationship with the TT-ILL. The high correlation between the LW and the horizontal MP location was observed, R(2)=0.764. Approximately 77% of the variance of the horizontal MP location index was accounted for by its linear relationship with the LW.
These findings indicate that the anatomical landmarks were useful to accurately predict MP locations for the TA muscle. Clinically, this MP location index using regression equations may be alternative for the current method that was not previously affordable.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to investigate the kinematic and kinetic changes that may occur in the pelvic and spine regions during cross-legged sitting postures. Experiments were performed on sixteen healthy subjects. Data were collected while the subject sat in 4 different sitting postures for 5 seconds: uncrossed sitting with both feet on the floor (Posture A), sitting while placing his right knee on the left knee (Posture B), sitting by placing right ankle on left knee (Posture C), and sitting by placing right ankle over the left ankle (Posture D). The order of the sitting posture was random. The sagittal plane angles (pelvic tilt, lumbar A-P curve, thoracic A-P curve) and the frontal plane angles (pelvic obliquity, lumber lateral curves, thoracic lateral curves) were obtained using VICON system with 6 cameras and analyzed with Nexus software. The pressure on each buttock was measured using Tekscan. Repeated one-way analysis of variance (ANOVA) was used to compare the angle and pressure across the four postures. The Bonferroni's post hoc test was used to determine the differences between upright trunk sitting and cross-legged postures. In sagittal plane, cross-legged sitting postures showed significantly greater kyphotic curves in lumbar and thoracic spine when compared uncrossed sitting posture. Also, pelvic posterior tilting was greater in cross-legged postures. In frontal plane, only height of the right pelvic was significantly higher in Posture B than in Posture A. Finally, in Posture B, the pressure on the right buttock area was greater than Posture A and, in Posture C, the pressure on the left buttock area was greater than Posture A. However, all dependent variables in both planes did not demonstrate any significant difference among the three cross-legged postures (p>.05). The findings suggest that asymmetric changes in the pelvic and spine region secondary to the prolonged cross-legged sitting postures may cause lower back pain and deformities in the spine structures.
[Show abstract][Hide abstract] ABSTRACT: We investigated the effects of four weeks of training using a knee extension with hip adduction (KEWHA) exercise in asymptomatic participants. In addition, we compared different methods of electromyographic (EMG) onset-time detection. Eighteen participants who achieved earlier activation of the vastus lateralis (VL) muscle compared to that of the vastus medialis obliquus (VMO) muscle performed the isometric KEWHA exercise in the sitting position for four weeks. A 15° hip adduction was added to the existing knee extension in the KEWHA exercise. EMG onset times were detected using a computer-analyzed system and evaluated using two methods in which the thresholds for activity onset were set at two and three standard deviations (SDs) of the mean baseline activity. No significant difference in the EMG onset-time for the VMO muscle was observed compared to that of the VL muscle between the pre- and post-tests (p>0.05) when data at 2SDs of the mean baseline activity were analyzed. However, a significant difference in the onset times for the VMO muscle and VL muscle was found between the pre- and post-tests (p<0.05) when data at 3SDs of the mean baseline activity were analyzed. In addition, less variation was observed in data analyzed at 3SDs compared to that of the data at 2SDs. The normalized VMO:VL muscle ratio was not significantly different between the pre- and post-tests. These findings show that the KEWHA exercise may decrease the difference between the onset times of VMO and VL muscles. In addition, we suggest that task-specific EMG onset-time detection methods are required to minimize variations in the data obtained during the recording of muscle activation.
Journal of electromyography and kinesiology: official journal of the International Society of Electrophysiological Kinesiology 09/2011; 21(6):1011-6. · 2.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The effects of passive correction of scapular position (PCSPT) on pain, proprioception, and range of motion (ROM) were investigated in neck-pain patients with bilateral scapular downward-rotation (SDR). Fifteen neck-pain patients with bilateral SDR were recruited from a workplace based work-conditioning center. The intensity of pain felt was quantified using a visual analogue scale. Kinematic data for ROM and joint-position error (JPE) were analyzed using a 3-dimensional motion-analysis system. Differences in pain, JPE, and ROM with and without PCSPT were assessed using a paired t-test. PCSPT significantly decreased JPE and neck pain during active neck rotation and significantly increased neck-rotation ROM (p < 0.05). These findings suggest that PCSPT results in decreased neck pain and improved neck-rotation ROM and proprioception during active neck rotation in neck-pain patients with bilateral SDR.
[Show abstract][Hide abstract] ABSTRACT: To determine the effect of novel augmented abdominal drawing-in maneuver (ADIM) training using rehabilitative ultrasound imaging (RUSI) and electromyography (EMG) in adults with core instability.
A convenience sample of 20 young adults with core instability (female =4; mean age ± standard deviation=24.4 ± 2.9 years) was recruited. Core instability was determined by the formal test. All subjects underwent an intensive ADIM that was augmented by comprehensive visual feedback via a pressure biofeedback unit, RUSI, and EMG. The intervention was provided for 20 minutes a day, 7 days a week, over a two-week period.
The paired t-test showed that both transverse abdominal (TrA) and internal oblique (IO) muscle thickness during ADIM were significantly greater than at rest (p= 0.000). However, external oblique (EO) muscle thickness remained relatively unchanged. The mean EMG amplitudes of the EO and erector spinae (ES) muscles were significantly decreased after the intervention (p=0.001, p=0.008). The intra-class correlation coefficient (ICC(1,2)) showed the excellent test-retest reliability for muscle thickness (ranging from 0.90 to 0.98 in the prone position).
This is the first evidence to demonstrate that the novel augmented ADIM training can effectively improve the lumbo-pelvic stabilization in adults with core instability.
Journal of Back and Musculoskeletal Rehabilitation 01/2011; 24(4):233-40. · 0.61 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To improve trunk stability or trunk muscle strength, many athletic trainers and physiotherapists use various types of unstable equipment for training. The round foam roll is one of those unstable pieces of equipment and may be useful for improving trunk stability.
To assess the effect of the supporting surface (floor versus round foam roll) on the activity of abdominal muscles during a single-legged hold exercise performed in the hook-lying position on the floor and on a round foam roll.
University research laboratory.
Nineteen healthy volunteers (11 men, 8 women) from a university population.
The participants were instructed to perform a single-legged hold exercise while in the hook-lying position on the floor (stable surface) and on a round foam roll (unstable surface).
Surface electromyography (EMG) signals were recorded from the bilateral rectus abdominis, internal oblique, and external oblique muscles. Dependent variables were examined with a paired t test.
The EMG activities in all abdominal muscles were greater during the single-legged hold exercise performed on the round foam roll than on the stable surface.
The single-legged hold exercise in the hooklying position on an unstable supporting surface induced greater abdominal muscle EMG amplitude than the same exercise performed on a stable supporting surface. These results suggest that performing the single-legged hold exercise while in the hook-lying position on a round foam roll is useful for activating the abdominal muscles.
Journal of athletic training 01/2011; 46(4):403-8. · 1.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The objective of this research was to examine the effects of lumber stabilization exercise and a general physiotherapy program for caregivers with chronic low back pain. Sixteen people participated in this study and were randomly assigned to two groups for either lumbar stabilization exercise or for general physiotherapy, respectively. The experiment was performed for eight weeks. To examine the general as well as the medical characteristics of the participants, the following measurements were used: Visual Analogue Scale (VAS); Oswestry Disability Index (ODI); Back Performance Scale (BPS); Roland - Morris Disability Questionnaire (RMDQ); and Beck Depression Index (BDI). To compare the general and medical characteristics of the participants in the two groups, an independent t test were used. During the experiment, a paired t test was conducted to determine whether there was a significant difference in the values of VAS, ODI, BPS, RMDQ, and BDI before and after the experiment. To examine the difference in the VAS, ODI, BPS, RMDQ, and BDI values in the two groups, ANCOVA was used with pre test values as a covariate. According to the test results, in the lumbar stabilization exercise group, the VAS, ODI, BPS, RMDQ, and BDI values showed a statistically significant difference before and after the test (p
[Show abstract][Hide abstract] ABSTRACT: We examined how the soleus H-reflex is affected by the changes in limb loading by testing subjects on a body weight support system during standing.
Twenty-two healthy subjects (10 males and 12 females) were recruited for this study. The size of the soleus H-reflex was measured in six different limb loading conditions: 100%, 90%, 80%, 70%, 60%, and 50%. One-way repeated measure ANOVA was used (p<0.05) to compare the H/M ratios among the six different load conditions.
The amplitudes of the soleus H-reflex decreased significantly as the amount of body weight load decreased.
Findings of this study suggest that the levels of body weight load in pre- and post-test conditions should be consistent when H-reflex testing is adapted as an outcome measure of rehabilitation intervention for patients with central nerve system lesion such as partial body weight supported gait training.
Journal of electromyography and kinesiology: official journal of the International Society of Electrophysiological Kinesiology 12/2010; 21(3):445-9. · 2.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to evaluate whether locomotor imagery training leads to clinical improvements in gait after stroke.
Pretest-posttest matched control design.
A total of 24 people with chronic hemiparetic stroke (13 for experimental and 11 for control) were recruited in this study.
The subjects in the experimental group participated in videotape-based locomotor imagery training five days a week for four weeks. They also conducted regular physical therapy.
Kinematic gait parameters were collected using a three-dimensional motion analysis system. Functional gait performance was assessed using clinical measures: Activities-specific Balance Confidence Scale, Berg Balance Test, Dynamic Gait Index and modified Emory Functional Ambulation Profile.
After training, walking velocity increased 0.07 +/- 0.06 m/s in the experimental group and 0.01 +/- 0.07 m/s in the control group. In the experimental group, the affected and less affected limb stride lengths increased by 0.09 +/- 0.12 m and 0.10 +/- 0.07 m respectively, whereas in the control group they decreased by 0.00 +/- 0.04 m and increased by 0.02 +/- 0.06 m, respectively. Kinematic parameters in the lower extremity joints during walking were more improved after the training in the experimental group. Confidence in balance, postural control, dynamic balance and performance time for different environmental walking situations were also improved more in the experimental group.
Locomotor imagery training can be considered as a useful option for restoration of ambulation for individuals with chronic hemiparetic stroke who are unable to participate in physical gait training.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to observe changes in electromyographic activity appeared in shoulder and scapular muscles when one wears no wrist extension orthosis, short wrist extension orthosis and long wrist extension orthosis when performing two model assembling operations. The study subjects were 16 adults who use right hand and did not have any functional disorder on their wrist or the upper limbs without any orthopedic surgery. The study subjects were asked to do the two model assembling operations without wrist extension orthosis, with a short wrist extension orthosis and with a long wrist extension orthosis. As a result of repetitive assembling operation that requires shoulder movement, electromyographic activity in upper trapezius and serratus anterior increased significantly when the subjects wore the short and long wrist extension orthoses compared to none. When the subjects performed repetitive assembling operation that requires shoulder stability, electromyographic activity in upper trapezius, lower trapezius, serratus anterior, and anterior deltoid showed significant increase when they wore the short and long wrist extension orthoses compared to none. Especially, the upper trapezius showed significantly high electromyographic activity when they wore the long wrist extension orthosis compared to a short one.
Industrial Health 01/2010; 48(1):108-14. · 0.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study was conducted to find the effects of scapular taping on muscle activities of the scapular rotators and upper trapezius pain in subjects with upper trapezius pain. Fifteen male subjects were recruited from Yonsei University for this study. Muscle activity of upper trapezius, lower trapezius, and serratus anterior was measured using surface electromyography. Visual analog scale was used for measuring upper trapezius pain. The subjects were asked to maintain shoulder flexion position with holding a 1 kg dumbbell in standing position. Scapular taping was applied over the muscle belly of the upper trapezius and attached parallel with the lower trapezius muscle fibers. For normalization, % maximal voluntary isometric contraction (%MVIC) was conducted. Paired t-test was applied to compare the muscle activities of scapular rotator and upper trapezius pain before and after applying the scapular taping. The muscle activity of the upper trapezius muscle and serratus anterior decreased significantly after tape application (p
[Show abstract][Hide abstract] ABSTRACT: To investigate the effect of motor imagery training (MIT) on the symmetrical use of knee extensors during sit-to-stand and stand-to-sit tasks.
We measured the electromyographic (EMG) data in the knee extensor on the affected side of 3 volunteers with post-stroke hemiparesis. We used a single-subject multiple-baseline research design across individuals. The EMG data were collected from knee extensors while performing the sit-to-stand and stand-to-sit tasks. The EMG activation and onset time ratios for the knee extensors were calculated by dividing the EMG activation and onset time of knee extensor action on the affected side by these on the unaffected side. MIT consisted of a 10-min detailed description of 5 stages: preparation, sit-to-stand tasks, weight shifting during standing, stand-to-sit tasks, and completion.
During MIT, the EMG activation ratios of participants 1, 2, and 3 increased by 11.24%, 18.07%, and 26.91%, respectively, in the sit-to-stand task and by 12.11%, 14.31%, and 25.92%, respectively, in the stand-to-sit task. During MIT, the onset time of participants 1, 2, and 3 decreased by 36.09%, 24.27%, and 25.61%, respectively, in the sit-to-stand task and by 26.81%, 27.20%, and 22.83%, respectively, for the stand-to-sit task.
These findings suggest that MIT has a positive effect on the symmetrical use of knee extensors during sit-to-stand and stand-to-sit tasks.