Effects of Shoulder Flexion Loaded by an Elastic Tubing Band on EMG Activity of the Gluteal Muscles during Squat Exercises

[Purpose] We investigated the effects of shoulder flexion loaded by an elastic tubing band during squat exercises, by assessing electromyographic activities of the gluteus maximus and gluteus medius. [Subjects] In total, 17 healthy males were recruited. [Methods] Participants performed squat exercises with and without shoulder flexion loaded by a tubing band. Gluteal muscle activities during the downward and upward phases of the squat exercises were recorded using a surface electromyography (EMG) system. The mean electromyographic activities of the gluteal muscles during squat exercises with and without loaded shoulder flexion were compared using the paired t-test. [Results] Electromyographic activities of the gluteus maximus and gluteus medius were greater in both the upward and downward phases of the squat with loaded shoulder flexion. [Conclusions] The combination of squat and loaded shoulder flexion can be an effective exercise for increasing gluteal muscle activity.Key words: Squat exercise, Gluteus maximus, Gluteus medius     

The Effect of Trunk Stabilization Exercises with a Swiss Ball on Core Muscle Activation in the Elderly

[Purpose] The purpose of this study was to investigate the effects of trunk stabilization exercise on the muscle EMG activations related to core stability. [Subjects and Methods] Fifteen elderly people in a geriatric hospital performed trunk stabilization exercises with a Swiss ball for 20 minutes five times per week for 8 weeks. Trunk muscle activations were measured using electromyography before and after the intervention. [Results] After the intervention, the muscle activations of the rectus abdominis, erector spinae, lateral low-back (quadratus lumborum and external oblique), and gluteus medius muscles increased significantly. [Conclusion] The trunk stabilization exercise with a Swiss ball significantly increased the muscle activities of the elderly.Key words: Elderly, Electromyography, Core stability     

The Effects of Sling Exercise Using Vibration on Trunk Muscle Activities of Healthy Adults

[Purpose] This study compared the effects of sling exercises with and without vibration on the muscular activity of the internal oblique (IO), rectus abdominis (RA), multifidus (MF), and erector spinae (ES) muscles of healthy adults. [Methods] Eleven healthy university students (11 men) with a mean age of 22.8 years were enrolled in this study. Subjects performed supine and prone bridge exercises with the knees flexed using a sling suspension system with and without vibration. The amplitudes of the EMG activities of selected trunk muscles (internal oblique, rectus abdominis, erector spinae, multifidus) were recorded. Two types of exercise conditions were executed in a random sequence for 5 seconds each. The signals detected from the middle 3 seconds (after discarding the signals of the first and the last one seconds) were used in the analysis. A 3-minute break was given after each exercise to minimize muscle fatigue. [Results] During the supine bridge exercise with vibration, the activities of the IO, RA, MF, and ES muscles were significantly higher than those of the supine bridge exercise without vibration. Additionally, during the prone bridge exercise with vibration, the activities of the IO, RA, MF, and ES were significantly higher than those of the prone bridge exercise without vibration. [Conclusion] Sling exercises with vibration improved the trunk muscle activities of healthy adults compared to the sling exercises without vibration. The information presented here is important for clinicians who use lumbar stabilization exercises as an evaluation tool or a rehabilitation exercise.Key words: Sling exercise, Vibration, Trunk muscle     

Effects of a Pelvic Belt on the EMG Activity of the Abdominal Muscles during a Single-leg Hold in the Hook-lying Position on a Round Foam Roll

[Purpose] This study investigated the effects of a pelvic belt on the electromyography (EMG) activity of the abdominal muscles during a single-leg hold in the hook-lying position on a round foam roll. [Subjects] Seventeen healthy female volunteers were recruited for this study. [Methods] The participants performed single-leg-hold exercises on a round foam roll with and without a pelvic belt. Surface EMG was recorded from the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) bilaterally. [Results] The EMG activity of the bilateral RA, EO, and IO was significantly lower when the pelvic belt applied. [Conclusions] Our finding that the bilateral EO, IO, and RA muscles were less active with a pelvic belt during trunk-stabilizing exercises on an unstable surface suggests that the pelvic belt provided “form closure”.Key words: Abdominal muscle, Pelvic belt, Round foam roll     

Effects of a Bridging Exercise with Hip Adduction on the EMG Activities of the Abdominal and Hip Extensor Muscles in Females

[Purpose] This study compared the activities of the abdominal and hip extensor muscles between the bridging exercise (BE) and bridging exercise with hip adduction (BEHA) positions in women using electromyography (EMG). [Subjects] We recruited 14 healthy adult females with no history of low back pain. [Methods] The subjects performed bridging exercises with and without hip adduction. The EMG activities of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and gluteus maximus (GM) muscles were recorded. [Result] The EMG activities of all muscles were significantly increased during the BEHA compared to the BE. [Conclusion] The bridging exercise with hip adduction produced greater activation of the abdominal and hip extensor muscles.Key words: Bridging exercise, EMG, Hip adduction     

Effects of selective exercise for the deep abdominal muscles and lumbar stabilization exercise on the thickness of the transversus abdominis and postural maintenance

[Purpose] The purpose of this study was to examine the effects of selective exercise for the deep abdominal muscles (SEDA) and lumbar stabilization exercise (LSE) on the thickness of the transversus abdominis and postural maintenance on an unstable base of support. [Subjects and Methods] The subjects of this study were 20 male and 10 female adults in their 20s without lumbar pain. They were equally and randomly assigned to a SEDA group and a LSE group. The thickness of the transversus abdominis was measured using ultrasound imaging during rest and drawing-in. The thickness of the transversus abdominis was measured when subjects raised their right and left legs while lying on a Swiss ball. [Results] Initially, there were no differences between the two groups. After the intervention, significant differences were observed in all parameters. A significant interaction between group and period was not found for any parameters. [Conclusion] In conclusion, both SEDA and LSE thickened the transversus abdominis, which is a deep abdominal muscle, thereby adjusting posture, and stabilizing the trunk. These exercises increased the thickness of the deep abdominal muscles. They are important exercises for improving the stability of athletes or patients who need postural adjustment.Key words: Transversus abdominis, Selective exercise, Lumbar stabilization     

SWISS BALL ABDOMINAL CRUNCH WITH ADDED ELASTIC RESISTANCE IS AN EFFECTIVE ALTERNATIVE TO TRAINING MACHINES

Background:

Swiss ball training is recommended as a low intensity modality to improve joint position, posture, balance, and neural feedback. However, proper training intensity is difficult to obtain during Swiss ball exercises whereas strengthening exercises on machines usually are performed to induce high level of muscle activation.

Purpose:

To compare muscle activation as measured by electromyography (EMG) of global core and thigh muscles during abdominal crunches performed on Swiss ball with elastic resistance or on an isotonic training machine when normalized for training intensity.

Methods:

42 untrained individuals (18 men and 24 women) aged 28–67 years participated in the study. EMG activity was measured in 13 muscles during 3 repetitions with a 10 RM load during both abdominal crunches on training ball with elastic resistance and in the same movement utilizing a training machine (seated crunch, Technogym, Cesena, Italy). The order of performance of the exercises was randomized, and EMG amplitude was normalized to maximum voluntary isometric contraction (MVIC) EMG.

Results:

When comparing between muscles, normalized EMG was highest in the rectus abdominis (P<0.01) and the external obliques (P<0.01). However, crunches on Swiss ball with elastic resistance showed higher activity of the rectus abdominis than crunches performed on the machine (104±3.8 vs 84±3.8% nEMG respectively, P<0.0001). By contrast, crunches performed on Swiss ball induced lower activity of the rectus femoris than crunches in training machine (27±3.7 vs 65±3.8% nEMG respectively, P<0.0001) Further, gender, age and musculoskeletal pain did not significantly influence the findings.

Conclusion:

Crunches on a Swiss ball with added elastic resistance induces high rectus abdominis activity accompanied by low hip flexor activity which could be beneficial for individuals with low back pain. In opposition, the lower rectus abdominis activity and higher rectus femoris activity observed in machine warrant caution for individuals with lumbar pain. Importantly, both men and women, younger and elderly, and individuals with and without pain benefitted equally from the exercises.     

Electromyographic Activities of Trunk Muscles Due to Different Exercise Intensities during Pulley-based Shoulder Exercises on an Unstable Surface

[Purpose] This study examined the relationship between core stability and exercise intensity during a pulley-based shoulder exercise (PBSE) on an unstable support surface. [Subjects] Twenty healthy college students enrolled in this study. [Methods] Surface EMG was carried out in twenty healthy adult men. The electromyographic activities of the rectus abdominis (RA), erector spinae (ES), exercises with 14 kg or 26 kg of resistance and external oblique (EO) muscles during pulley-based shoulder on an unstable support surface (USS) were compared. [Results] The EMG signals of the RA, ES, and EO did not increase with increasing exercise resistance. [Conclusion] Increasing the exercise intensity to increase the core stability during PBSE on a USS may be ineffective.Key words: Electromyography, Core stability, Ankle strategy     

Electromyographic analysis of trunk and lower extremity muscle activities during pulley-based shoulder exercises performed on stable and unstable surfaces

[Purpose] The aim of the present study was to identify the effects of an unstable support surface (USS) on the activities of trunk and lower extremity muscles during pulley-based shoulder exercise (PBSE). [Subjects] Twenty healthy college students were included in this study. [Methods] Surface EMG was carried out in twenty healthy adult men. The activities of trunk and lower extremity muscles performed during PBSE using a resistance of 14 kg on a stable or unstable support surface were compared. The PBSE included shoulder abduction, adduction, flexion, extension, internal rotation, and external rotation. [Results] On the unstable surface, the rectus abdominis and erector spinae showed significantly less activation during shoulder external rotation, but the extent of activation was not significantly different during other shoulder exercises. The external oblique and rectus femoris showed no significant difference during any shoulder exercises. The tibialis anterior showed significantly greater activation during all shoulder exercises, except flexion and extension. The gastrocnemius showed significantly greater activation during shoulder abduction, extension, and internal rotation. However, during shoulder adduction, flexion, and external rotation, the gastrocnemius showed no significant difference. [Conclusion] The use of USS to increase core stability during PBSE is probably not effective owing to compensatory strategies of the ankle.Key words: Electromyography, Core stability, Ankle strategy     

Selective Activation of Lumbar Paraspinal Muscles during Various Exercises in the Prone Position as Measured by EMG

[Purpose] This study compared the effects of three exercises performed in a prone position on the selective activation of the lumbar erector spinae (LES) and lumbar multifidus (LM) muscles in healthy males to investigate the effective method for selective activation of the LM. [Subjects] Twenty-two healthy males were recruited. Surface EMG data were collected from the right LES and LM muscles during three exercises: 1) trunk extension, 2) hip extension, and 3) the arm lift. [Results] The ratio of LM to LES EMG activity during hip extension was higher than those during trunk extension and the arm lift. [Conclusion] Hip extension in a prone position may be effective for selective activation of the lumbar multifidus muscles in healthy males.Key words: Lumbar erector spinae, Lumbar multifidus, Selective activation     

Differences in Muscle Activities of the Infraspinatus and Posterior Deltoid during Shoulder External Rotation in Open Kinetic Chain and Closed Kinetic Chain Exercises

[Purpose] This study investigated the changes in electromyographic (EMG) activities of the infraspinatus and posterior deltoid muscles during shoulder external rotation under open kinetic chain (OKC) and closed kinetic chain (CKC) exercise conditions. [Subjects] In total, 15 healthy males participated in this study. [Methods] Subjects performed shoulder external rotations under CKC and OKC conditions while standing with and without weight support provided by a height-adjustable table. Pressure biofeedback was used to ensure a constant amount of weight support. The activities of the infraspinatus and posterior deltoid muscles during shoulder external rotation were measured using a wireless surface EMG system. The paired t-test was used to compare the EMG activities of the infraspinatus and the posterior deltoid muscles and the ratio of the infraspinatus to the posterior deltoid during shoulder external rotation under OKC and CKC conditions. [Results] The EMG activity of the infraspinatus and the ratio of the infraspinatus to the posterior deltoid activities were significantly increased, whereas the posterior deltoid activity was significantly decreased under the CKC condition compared to the OKC condition. [Conclusion] Clinicians should consider the CKC shoulder external rotation exercise when they wish to selectively strengthen the infraspinatus.Key words: Infraspinatus, Posterior deltoid, Selective muscle strengthening     

The Effects of Closed Kinetic Chain Exercises and Open Kinetic Chain Exercises Using Elastic Bands on Electromyographic Activity in Degenerative Gonarthritis

[Purpose] The purpose of this study was to examine the effects of closed kinetic chain exercises (CKCEs) and open kinetic chain exercises (OKCEs) with elastic bands on the electromyographic activity of patients with degenerative gonarthritis. [Subjects] The study subjects were 30 degenerative gonarthritis patients who were divided into a CKCE group (CKCEG, n=10), an OKCE group (OKCEG, n=10), and a control group (CG, n=10). [Methods] The CKCEG and the OKCEG performed exercises with elastic bands, and the CG took part in a quadriceps strengthening exercise. All three groups performed the exercises three times per week for four weeks. The electromyographic activities of the subjects’ vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), semitendinosus (ST), and biceps femoris (BF) muscles were measured and compared. [Results] Within-group comparisons revealed that the electromyographic activities of the VM, RF, VL, ST, and BF muscles increased significantly in the CKCEG. The OKCEG displayed significant increases in the electromyographic activity of the VM, RF, ST, and BF muscles, and the CG showed significant increases in the electromyographic activities of the RF, VL, ST, and BF muscles. In between-group comparisons after the intervention, the electromyographic activities of the VM, RF, and VL muscles of the CKCEG were significantly higher than those of the CG. The electromyographic activities of the VM, RF, and ST muscles of the OKCEG were significantly higher than those of the CG. [Conclusion] We consider CKCEs with elastic bands are an effective intervention for increasing the electromyographic activities of the VM, RF, VL, ST, and BF muscles of degenerative gonarthritis patients, and OKCEs with elastic bands are an effective intervention for increasing the electromyographic activities of the VM, RF, ST, and BF muscles of degenerative gonarthritis patients.     

Effects of performing an abdominal hollowing exercise on trunk muscle activity during curl-up exercise on an unstable surface

[Purpose] The purpose of this study was to investigate the effects of the abdominal hollowing exercise on trunk muscle activity during the curl-up exercise on an unstable surface by measuring electromyography (EMG) activity. [Subjects] Fourteen young healthy adults (nine male, five female) voluntarily participated in this study. [Methods] Each subject was asked to perform a curl-up exercise on two supporting surfaces (stable and unstable surfaces) combined with the abdominal hollowing exercise on an unstable surface. The muscle activities of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) were measured using surface EMG during performance of the curl-up exercise. [Results] The EMG activity of the RA and EO was significantly higher on an unstable surface than on a stable surface during the curl-up exercise. The EMG activities of the TrA and IO were greater in combination with the abdominal hollowing exercise on an unstable surface than during the curl-up exercise on both a stable and unstable surface. [Conclusion] These findings suggest that the local trunk muscle activity during the curl-up exercise is more strongly affected by combination with the abdominal hollowing exercise than by performance on an unstable supporting surface.Key words: Abdominal hollowing exercise, Curl-up exercise, Unstable surface     

Changes in the Activities of the Trunk Muscles in Different Kinds of Bridging Exercises

[Purpose] The purpose of this study was to examine the effects of different types of bridging exercises on the activities of the trunk muscles. [Methods] Twenty-four students participated in this experiment. The activities of the internal oblique (IO), external oblique (EO), rectus abdominis (RA), and erector spinae (ES) muscles were measured in four different bridging exercises. [Results] There were significant differences in the IO, EO, RA, and ES among the four kinds of bridging exercise. The activities of IO, EO and RA were the highest in prone bridging (exercise 4), followed by unilateral bridging (exercise 3), and supine bridging on balance pads (exercise 2). In conventional bridging (exercise 1), the activities of IO, EO, and RA were the lowest. The activity of ES was the highest in exercise 3 followed by exercises 2 and 1. The activity of ES was the lowest than in exercise 1. [Conclusions] Bridging exercise in the prone position may be a more effective method of enhancing trunk muscle activities exercises in other positions.Key words: Bridge exercise, Muscle activity, EMG     

Comparison of trunk and hip muscle activity during different degrees of lumbar and hip extension

[Purpose] This study compared the activity of trunk and hip muscles during different degrees of lumbar and hip extension. [Subjects] The study enrolled 18 participants. [Methods] Two exercises (hip and lumbar extension) and two ranges (180° and <180°) were studied. [Results] Differences in degree of extension affected the percentage maximal voluntary isometric contraction of the lumbar erector spinae and biceps femoris muscles, with significantly higher average values at >180° than at 180° lumbar extension. No significant differences were found in gluteus maximus activity according to exercise type or range. [Conclusion] Hip extension may be more effective and safer for lumbar rehabilitation than lumbar extension.Key words: EMG, Hip extension, Lumbar extension     

Comparison of the isolated contraction ratios of the hip extensors and erector spinae muscles of the lumbar region and thoracic muscles during different back extension exercises

[Purpose] This study compared the isolated contraction ratios of the hip extensors, erector spinae muscles of the lumbar region, and thoracic muscles during different back extension exercises. [Subjects] Twelve males participated in this study. [Methods] The subjects performed various back extension exercises. The activities of the T7 erector spinae muscles, L3 erector spinae muscles, and the gluteus maximus were measured, and the isolation contraction ratios were calculated. [Results] The isolated contraction ratio of the T7 erector spinae muscles significantly increased during exercise 2. The isolated contraction ratio of the gluteus maximus increased by a significant degree during exercise 1 compared with the other exercises. [Conclusion] This study demonstrated that the back extension exercises 1 and 2 can be applied to selectively exercise the hip extensors, thoracic muscles, and muscles of the lumbar region.Key words: Back extensor, Isolated contraction ratio, Selected exercise     

Surface EMG during the Push-up plus Exercise on a Stable Support or Swiss Ball: Scapular Stabilizer Muscle Exercise

[Purpose] Scapular stabilizer strengthening exercise is crucial for shoulder rehabilitation. The purpose of this study was to compare two types of push-up plus exercises, on a stable and unstable bases of support, using surface electromyography (EMG), to suggest an effective shoulder rehabilitation program. [Subjects and Methods] Ten healthy men volunteered for this study. All volunteers performed two sets of push-up plus exercise (standard push up and knee push up) on stable and unstable bases of support. The muscle activities of five important scapular stabilizer muscles (upper trapezius, middle trapezius, lower trapezius, serratus anterior, latissimus dorsi) were recorded during the exercise. [Results] The upper trapezius showed greater mean electric activation amplitude in the scapular retraction posture than in the scapular protraction posture, and the serratus anterior showed greater mean electric activation amplitude in the scapular protraction posture than in the scapular retraction posture. The root-mean-square normalized EMG values of the muscles were greater during the exercise performed on the unstable support than those on the stable support. [Conclusion] The standard push-up plus exercise on an unstable base of support helps to increase muscle activity, especially those of the upper/middle trapezius and serratus anterior.Key words: Scapular stabilizer, Push-up plus, Surface EMG     

Comparison of physical function according to the lumbar movement method of stabilizing a patient with chronic low back pain

[Purpose] The purpose of this study was to examine the changes caused by lumbar stabilization exercises in chronic low back pain patients. [Subjects and Methods] Swiss ball exercise regimen group and sling exercise regimen group exercised for 30 minutes a day, 5 days a week, for 12 weeks. The control group was to continue performing their usual daily living activities. [Results] We obtained significant results in both the Swiss ball and sling exercise groups, but not in the control group. The best effect was obtained in the sling exercise group. [Conclusion] The Oswestry Low Back Pain Disability Index and visual pain scale scores of the patients with low back pain decreased in both the Swiss ball exercise group and the sling exercise group, and these patients experienced an increase in waist isometric muscular strength after 12 weeks of exercise compared with those doing no exercise (the control group).Key words: Lumbar stabilizing, Sling exercise, Chronic back pain     

Impact of post-manipulation corrective core exercises on the spinal deformation and lumbar strength in golfers: a case study

[Purpose] This study examined spinal shape in professional golfers with chronic back pain, and analyzed the effects of a 4-week regimen of semi-weekly manipulation and corrective core exercises on spinal shape. [Subjects] Two golfers with chronic back pain. [Methods] The pelvis and spinal vertebrae were corrected using the Thompson “drop” technique. Angle and force were adjusted to place the pelvis, lumbar spine, and thoracic vertebrae in neutral position. The technique was applied twice weekly after muscle massage in the back and pelvic areas. The golfers performed corrective, warmup stretching exercises, followed by squats on an unstable surface using the Togu ball. They then used a gym ball for repetitions of hip rotation, upper trunk extension, sit-ups, and pelvic anterior-posterior, pelvic left-right, and trunk flexion-extension exercises. The session ended with cycling as a cool-down exercise. Each session lasted 60 minutes. [Results] The difference in height was measured on the left and right sides of the pelvic bone. The pelvic tilt changed significantly in both participants after the 4-week program. [Conclusion] In golfers, core muscles are critical and are closely related to spinal deformation. Core strengthening and spinal correction play a pivotal role in the correction of spinal deformation.Key words: Chronic back pain, Manipulation, Core exercise     

The Effects of Bridge Exercise on an Unstable Base of Support on Lumbar Stability and the Thickness of the Transversus Abdominis

[Purpose] We examined the effects of an abdominal drawing-in bridge exercise using a pressure biofeedback unit on different bases on the thickness of trunk and abdominal muscles, and lumbar stability. [Subjects] Thirty healthy young adults (2 males, 28 females) took part in this study. The subjects were randomly and equally assigned to a stable bridge exercise group and an unstable bridge exercise group. [Methods] The subjects performed bridge exercises using an abdominal drawing-in method on a stable base and on an unstable base, and changes in their abdominal muscle thickness and on the stable and on unstable bases lumbar stability were evaluated. [Results] After the intervention, the stable bridge exercise group showed a statistically significantly increased muscle thickness in the transversus abdominis, and the unstable bridge exercise group showed significantly increased muscle thicknesses of the transversus abdominis and internal obliques in static and dynamic lumbar stability. The unstable bridge exercise group showed significant increase after performing the exercise. [Conclusion] Lumbar stability exercise, with the compensation of the lumbar spine minimized, using an abdominal drawing-in method on an unstable support of base is effective and efforts to prevent the compensation may induce a greater exercise effect.Key words: Bridge exercise, Abdominal drawing-in method, Transversus abdominis