Abdominal muscle activity according to knee joint angle during sit-to-stand.

[Purpose] This study assessed the activity of the abdominal muscles according to the angle of the knee joints during sit-to-stand. [Subjects and Methods] Thirty healthy adult males participated in this study. Subjects initiated sit-to-stand at knee joint angles of 60°, 90°, or 120°. An electromyography system was used to measure the maximum voluntary isometric contraction of the rectus abdominis, external oblique, and internal oblique and transverse abdominis muscles. [Results] Percent contraction differed significantly among the three knee joint angles, most notably for the internal oblique and transverse abdominis muscles. [Conclusion] Wider knee joint angles more effectively activate the abdominal muscles, especially those in the deep abdomen, than do narrower angles.

Differences in abdominal muscle activation during coughing between smokers and nonsmokers.

[Purpose] The purpose of this study was to compare the activity of the abdominal muscles during coughing between smokers and nonsmokers. [Subjects] A total of 30 healthy adults (15 smokers, 15 nonsmokers) participated. [Methods] The percentage maximal voluntary isometric contraction values (%MVIC) of the rectus abdominis (RA), external abdominal oblique (EO), and internal abdominal oblique (IO) and transversus abdominis (TrA) were measured using surface electromyography. [Results] The %MVIC of the IO and TrA statistically significantly differed and the %MVIC of IO and TrA was found to be higher during coughing in nonsmokers compared with during coughing in smokers. [Conclusion] The activity of the deep abdominal muscles in nonsmokers was also higher than that of smokers during coughing.

Differences in the activation of abdominal muscles during trunk extension between smokers and non-smokers.

BACKGROUND: Many studies reported that the morbidity of the respiratory and circulatory diseases is higher among smokers than non-smokers. Some recent studies reported the effects of smoking on the musculoskeletal system. However, it is difficult to generalize the experimental environment because it is different from activities of daily living environment. OBJECTIVE: The purpose of this study was to compare the differences in the activation of abdominal muscles during trunk extension between smokers and non-smokers. METHODS: The subjects were 30 healthy adults (15 smokers and 15 non-smokers). The percentage of maximal voluntary isometric contraction (%MVIC) values of rectus abdominis (RA), external oblique (EO), internal oblique and transversus abdominis(IO&TrA) were measured using the surface electromyography System. RESULTS: The results showed no significant differences in the %MVIC of RA and EO between smokers and non-smokers. However, the %MVIC of IO&TrA showed a significant difference between smokers and non-smokers. The %MVIC of IO&TrA of non-smokers was higher. CONCLUSIONS: The non-smokers showed greater activation of deep abdominal muscles than smokers did.

Internal- and External-Rotation Peak Toque in Little League Baseball Players With Subacromial Impingement Syndrome: Improved by Closed Kinetic Chain Shoulder Training.

CONTEXT: Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain. OBJECTIVE: To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players. DESIGN: Single-group pretest, posttest. SETTING: Biomechanics laboratory. PARTICIPANTS: 23 Little League Baseball players with subacromial impingement syndrome. INTERVENTIONS: The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk. MAIN OUTCOME MEASURES: The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s. RESULTS: The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s. CONCLUSIONS: CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.

Muscle tone changes in the lower limbs of stroke patients induced by trunk stabilization exercises.

bstract. [Purpose] The purpose of this study was to identify the effects of trunk stabilization exercises on the spasticity of the lower limbs in stroke patients. [Subject] The subject of this study was a 38-year-old male patient who experienced a spontaneous intracranial hemorrhage, and had motor paralysis symptoms and spasticity on the left side. [Methods] The Hmax/Mmax ratio was measured before and after the trunk stabilization exercises, by using proprioceptive neuromuscular facilitation techniques. [Results] The Hmax/Mmax ratio changed from 37% to 20%. [Conclusion] Trunk stabilization exercises help control the muscle tone in stroke patients.

Effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function.

[Purpose] To determine the effects of cervical sustained natural apophyseal glide on forward head posture and respiratory function. [Subjects and Methods] Thirty male and female adults in their 20s with forward head posture were included in the study. The subjects were divided randomly into experimental and control groups (n=15 each). Subjects in the experimental group performed cervical sustained natural apophyseal glide three times/week for four weeks while subjects in the control group did not perform the intervention. The craniovertebral angle, forced vital capacity and forced expiratory volume in the first second, as well as the % predicted value of each measurement were assessed to determine the changes in respiration functions before and after the exercise. [Results] The craniovertebral angle four weeks after the experiment was increased in the experimental group, whereas the control group showed no significant difference compared to baseline. The forced vital capacity, forced expiratory volume in the first second, and the % predicted values thereof were significantly increased in the experimental group four weeks after the experiment, but not in the control group. [Conclusion] Cervical sustained natural apophyseal glide was determined to be effective in improving neck posture and respiratory functions for patients with forward head posture.

Reliability and validity of the closed kinetic chain upper extremity stability test.

[Purpose] The purpose of this study was to examine the reliability and validity of the Closed Kinetic Chain Upper Extremity Stability (CKCUES) test. [Subjects and Methods] A sample of 40 subjects (20 males, 20 females) with and without pain in the upper limbs was recruited. The subjects were tested twice, three days apart to assess the reliability of the CKCUES test. The CKCUES test was performed four times, and the average was calculated using the data of the last 3 tests. In order to test the validity of the CKCUES test, peak torque of internal/external shoulder rotation was measured using an isokinetic dynamometer, and maximum grip strength was measured using a hand dynamometer, and their Pearson correlation coefficients with the average values of the CKCUES test were calculated. [Results] The reliability of the CKCUES test was very high (ICC=0.97). The correlations between the CKCUES test and maximum grip strength (r=0.78-0.79), and the peak torque of internal/external shoulder rotation (r=0.87-0.94) were high indicating its validity. [Conclusion] The reliability and validity of the CKCUES test were high. The CKCUES test is expected to be used for clinical tests on upper limb stability at low price.

The changes of pulmonary function and pulmonary strength according to time of day: a preliminary study.

[Purpose] The purpose of this study was to identify changes in pulmonary function and pulmonary strength according to time of day. [Subjects and Methods] The subjects were 20 healthy adults who had no cardiopulmonary-related diseases. Pulmonary function and pulmonary strength tests were performed on the same subjects at 9:00 am, 1:00 pm, and 5:00 pm. The pulmonary function tests included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and forced expiratory flow between 25 and 75% of vital capacity (FEF25-75%). Pulmonary strength tests assessed maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). [Results] FEV1 showed statistically significant differences according to time of day. Other pulmonary function and pulmonary strength tests revealed no statistical differences in diurnal variations. [Conclusion] Our findings indicate that pulmonary function and pulmonary strength tests should be assessed considering the time of day and the morning dip phenomenon.

Difference in lateral abdominal muscle thickness during forceful exhalation in healthy smokers and non-smokers.

BACKGROUND AND OBJECTIVES: The present study aims to determine whether the internal oblique (IO) and transversus abdominis (TrA) muscles, which are major lumbar stabilisers and also expiratory muscles, are affected by smoking. METHODS: A total of 31 healthy individuals in their 20s (smokers: 15; non-smokers: 16) voluntarily participated in the study. They were made to maintain an upright standing posture with their scapulars on the wall. Then measurement was taken on the thickness of their right IO and TrA while they were at rest and in a state of forced expiration using a 7.5 MHz linear probe, an ultrasonic imaging system. The thickness of the muscles was converted into the percentage of change in muscle thickness (PCMT) and relative contribution ratio (RCR) using a calculation formula, and then the data were analysed. RESULTS: Significant differences were found between the two groups in the PCMT of the TrA and in the RCR of both TrA and IO. CONCLUSION: Smokers have a relatively higher degree of dependence on IO than TrA during forceful expiratory conditions compared with non-smokers. This relative overreaction of the IO is considered to likely cause problems in efficiently diffusing loads of the spine.