Won-Hwee Lee

A comparison in the muscle activity of the abductor hallucis and the medial longitudinal arch angle during toe curl and short foot exercises

OBJECTIVE To compare the muscle activity of the abductor hallucis (AbdH) and the medial longitudinal arch (MLA) angle during toe curl (TC) and short foot (SF) exercises while sitting or in one-leg standing position. DESIGN Two-way repeated-measures ANOVA was used to analyze the effects of exercise type and position on the muscle activity of the AbdH and the MLA angle. PARTICIPANTS Twenty subjects with normal feet participated in this study. MAIN OUTCOME MEASURES The muscle activity of the AbdH and the MLA angle were measured during TC and SF exercises while sitting or in one-leg standing position. RESULTS The EMG activity of AbdH in SF exercise was significantly greater than during TC exercise in both exercise postural positions (p < 0.001). During the SF exercise, the EMG activity of the AbdH in the one-leg standing position was significantly higher than that while sitting (p < 0.001). The MLA angle in SF exercise was significantly smaller than during TC exercise in both postural positions (p < 0.001). CONCLUSIONS These results suggest that SF exercise is a more useful strengthening exercise than TC exercise in activating the AbdH muscle.

Effects of the Abdominal Drawing-In Maneuver on Muscle Activity, Pelvic Motions, and Knee Flexion During Active Prone Knee Flexion in Patients With Lumbar Extension Rotation Syndrome

OBJECTIVE To investigate the effects of performing an abdominal drawing-in maneuver (ADIM) during active prone knee flexion on the hamstrings and erector spinae muscle activity, the amounts of pelvic motion and knee flexion, and onset of pelvic movements. DESIGN Comparative, repeated-measures study. SETTING University research laboratory. PARTICIPANTS Men patients (N=18) with lumbar extension rotation syndrome. INTERVENTION Subjects performed prone knee flexion in 2 conditions. MAIN OUTCOME MEASURES To measure muscle activity, surface electromyogram (EMG) of both erector spinae and the medial and lateral hamstrings was performed. Kinematic data on the pelvic motion and knee flexion were measured using a 3-dimensional motion analysis system. Repeated 1-way analysis of variance was used for the statistical analysis. RESULTS Significantly decreased electromyographic activity in the right and left erector spinae and significantly increased electromyographic activity in the medial and lateral hamstrings activity were shown during prone knee flexion in ADIM condition using the pressure biofeedback unit. In addition, the amounts of anterior pelvic tilt, pelvic rotation, knee flexion, and perceived pain decreased significantly during prone knee flexion in the ADIM condition compared with the same maneuver in the non-ADIM condition. The onset of anterior pelvic tilt and pelvic rotation occurred significantly earlier in the non-ADIM condition, compared with the ADIM condition. CONCLUSIONS ADIM effectively increased activation of knee flexors, decreased activation of back extensors, and reduced the pelvic motions and low back pain during prone knee flexion in patients with lumbar extension rotation syndrome.

Real-time visual feedback can be used to activate scapular upward rotators in people with scapular winging: an experimental study

QUESTION Can real-time visual feedback facilitate the activity of serratus anterior in individuals with scapular winging during shoulder flexion? DESIGN Comparative, repeated-measures experimental study. PARTICIPANTS Nineteen subjects with scapular winging. INTERVENTION Participants performed isometric shoulder flexion at 60° and 90° with and without real-time visual feedback using a video camera to monitor scapular winging. OUTCOME MEASURES Activity in the upper trapezius, lower trapezius, and serratus anterior muscles was measured using surface electromyography. A video motion analysis system measured the displacement of a marker attached to the acromion in the frontal and sagittal planes. RESULTS Visual feedback significantly increased activity in the upper trapezius at 60° of shoulder flexion by 2.3% of maximum voluntary isometric contraction (95% CI 0.7 to 4.0). Visual feedback also significantly increased activity in the serratus anterior at 60° and 90° of shoulder flexion, by 3.0% (95% CI 2.3 to 3.6) and 5.9% (95% CI 3.3 to 8.5) of maximum voluntary isometric contraction respectively. These effects equated to effect sizes from 0.29 to 0.46. Visual feedback also significantly improved movement of the acromion superiorly at 60° of shoulder flexion and anteriorly at 60° and 90° of shoulder flexion. CONCLUSION Real-time visual feedback can be used to activate the upper trapezius and serratus anterior muscles and to improve movement of the scapula during shoulder flexion in people with scapular winging.

Comparison of electromyographic activity of the lower trapezius and serratus anterior muscle in different arm-lifting scapular posterior tilt exercises

OBJECTIVE To determine the most effective exercise to specifically activate the scapular posterior tilting muscles by comparing muscle activity generated by different exercises (wall facing arm lift, prone arm lift, backward rocking arm lift, backward rocking diagonal arm lift). DESIGN Repeated-measure within-subject intervention. PARTICIPANTS The subjects were 20 healthy young men and women. MAIN OUTCOME MEASURES Lower trapezius (LT) and serratus anterior (SA) muscle activity was measured when subjects performed the four exercises. RESULTS Muscle activity was significantly different among the four exercise positions (p<0.05). The backward rocking diagonal arm lift elicited significantly greater activity in the LT muscle than did the other exercises (p<0.05). The backward rocking arm lift showed significantly more activity in the SA muscle than did the other exercises (p<0.05). CONCLUSIONS Clinicians can use these results to develop scapular posterior tilting exercises that specifically activate the target muscle.

Effects of breathing maneuver and sitting posture on muscle activity in inspiratory accessory muscles in patients with chronic obstructive pulmonary disease

BackgroundTo determine the influence of breathing maneuver and sitting posture on tidal volume (TV), respiratory rate (RR), and muscle activity of the inspiratory accessory muscles in patients with chronic obstructive pulmonary disease (COPD).MethodsTwelve men with COPD participated in the study. Inductive respiratory plethysmography and surface electromyography were used to simultaneously measure TV, RR, and muscle activity of the inspiratory accessory muscles [the scalenus (SM), sternocleidomastoid (SCM), and pectoralis major (PM) muscles] during quiet natural breathing (QB) and pursed-lips breathing (PLB) in three sitting postures: neutral position (NP), with armm support (WAS), and with arm and head support (WAHS).ResultsTwo-way repeated-measures analysis of variance was employed. In a comparison of breathing patterns, PLB significantly increased TV and decreased RR compared to QB. Muscle activity in the SM and SCM increased significantly in PLB compared to QB. In a comparison of sitting postures, the muscle activity of the SM, SCM, and PM increased in the forward-leaning position.ConclusionsThe results suggest that in COPD, PLB induced a favorable breathing pattern (increased TV and reduced RR) compared to QB. Additionally, WAS and WAHS positions increased muscle activity of the inspiratory accessory muscles during inspiration versus NP. Differential involvement of accessory respiratory muscles can be readily studied in COPD patients, allowing monitoring of respiratory load during pulmonary rehabilitation.

Selective Activation of the Infraspinatus Muscle

CONTEXT To improve selective infraspinatus muscle strength and endurance, researchers have recommended selective shoulder external-rotation exercise during rehabilitation or athletic conditioning programs. Although selective strengthening of the infraspinatus muscle is recommended for therapy and training, limited information is available to help clinicians design a selective strengthening program. OBJECTIVE To determine the most effective of 4 shoulder external-rotation exercises for selectively stimulating infraspinatus muscle activity while minimizing the use of the middle trapezius and posterior deltoid muscles. DESIGN Cross-sectional study. SETTING University research laboratory. PATIENTS OR OTHER PARTICIPANTS A total of 30 healthy participants (24 men, 6 women; age = 22.6 ± 1.7 years, height = 176.2 ± 4.5 cm, mass = 65.6 ± 7.4 kg) from a university population. INTERVENTION(S) The participants were instructed to perform 4 exercises: (1) prone horizontal abduction with external rotation (PER), (2) side-lying wiper exercise (SWE), (3) side-lying external rotation (SER), and (4) standing external-rotation exercise (STER). MAIN OUTCOME MEASURE(S) Surface electromyography signals were recorded from the infraspinatus, middle trapezius, and posterior deltoid muscles. Differences among the exercise positions were tested using a 1-way repeated-measures analysis of variance with Bonferroni adjustment. RESULTS The infraspinatus muscle activity was greater in the SWE (55.98% ± 18.79%) than in the PER (46.14% ± 15.65%), SER (43.38% ± 22.26%), and STER (26.11% ± 15.00%) (F3,87 = 19.97, P < .001). Furthermore, the SWE elicited the least amount of activity in the middle trapezius muscle (F3,87 = 20.15, P < .001). Posterior deltoid muscle activity was similar in the SWE and SER but less than that measured in the PER and STER (F3,87 = 25.10, P < .001). CONCLUSIONS The SWE was superior to the PER, SER, and STER in maximizing infraspinatus activity with the least amount of middle trapezius and posterior deltoid activity. These findings may help clinicians design effective exercise programs.

Effect of sleep posture on neck muscle activity

[Purpose] This study investigated the effect of sleep posture on neck muscle activity. [Subjects and Methods] The study recruited 20 healthy subjects, who were positioned in three supine sleeping positions: both hands at sides, both hands on the chest, and dominant hand on the forehead. The activities of the scalene and upper trapezius muscles bilaterally were measured by surface electromyography. [Results] The upper trapezius and scalene muscle activity on the right side was significantly greater in the supine with dominant hand on the forehead position than in the other positions. [Conclusion] Sleep posture is important and prevent neck and shoulder musculoskeletal pain.

Analysis of the relationships among perceived service encounter quality, service value, satisfaction and behavioral intention for physical therapy patients

[Purpose] The purpose of this study was to investigate the relationships among perceived service encounter quality, service value, patient satisfaction, and behavioral intention in physical therapy patients. [Subjects and Methods] This study surveyed 335 patients who received physical therapy treatment at five medical institutions in Jeonju-si, Republic of Korea. This study conducted path analysis on the collected data using Smart PLS 2.0 M3. [Results] The analysis of this study showed that service encounter quality had significantly positive relationship with service value, patient satisfaction, and behavioral intention. Service value had significantly positive relationship with patient satisfaction and behavioral intention. Patient satisfaction had significantly positive relationship with behavioral intention. [Conclusion] Improving the perceived quality of service encounters for physical therapy patients increases service value and patient satisfaction, and positively influences behavioral intention.