• Physical Therapy Rehabilitation Science
• /
• v.7 no.2
• /
• pp.72-77
• /
• 2018

Objective: This study aimed to compare the effects of core exercise methods on muscle activation and muscle thickness in healthy young adults and to propose effective core exercise methods. Design: Three-group pretest-posttest design. Methods: A total of 30 healthy young adults (14 males, 16 females) voluntarily participated in the study. Subjects were randomized to the prone plank exercise (n=10), reverse plank exercise (n=10), or bridge exercise (n=10) groups. Muscle activity and thickness of the rectus abdominis (RA), multifidus (MF), external oblique (EO), and internal oblique (IO) muscles were measured using surface electromyography and ultrasound. Subjects from each group participated in the exercises five times a week, with five 20-second sets during week 1. The set time was increased by 10 seconds per week. Results: Muscle activity and thickness in the prone plank, reverse plank, and bridge exercise group were statistically significant different for RA, MF, EO, and IO changes over time, and interaction between time and groups were also significantly different (p<0.05). We analyzed statistically significant differences between groups using a one-way analysis of variance for each period. A significant difference was observed after 4 weeks of exercise (p<0.05). Conclusions: The results suggest that the prone plank exercise is a beneficial method for enhancing muscle activation and thickness of the RA, EO, and IO compared to the reverse plank and bridge exercises. On the other hand, the reverse plank and bridge exercises are effective methods for enhancing the MF compared to the prone plank exercise.

• Journal of The Korean Society of Integrative Medicine
• /
• v.7 no.3
• /
• pp.197-204
• /
• 2019

Purpose: The purpose of this study was to investigate the effects of the plank exercise to strengthen the core muscles on the muscle thickness of external and internal obliques and transverse abdominis muscle depending on the form of the support surface. Methods: This study was randomized to 12 males and 12 females in their 20s and conducted three times a week for 4 weeks. The subjects were divided into the two groups and performed flank exercise on a stable surface (stable surface group) and an unstable surface (unstable surface group). A mat was used as a stable surface, and an TOGU used as a unstable surface. Results : In both stable and unstable surface, the thickness changes of the transverse abdominis and external and internal oblique muscle increased (p<.05). In the unstable surface, there was a greater increase in the thickness change of the transverse abdominis and external oblique muscles in the flank exercise than in the stable surface (p.<05). Among them, the greatest increase was found in the external abdominal muscle (p<.05). Conclusion : This study found that the flank exercise was more effective in strengthening the abdominal muscles on an unstable surface, when compared with the outcomes on a stable one. It is also thought to have the most effect on the muscle activity of the external oblique muscle on unstable surface.

• Journal of The Korean Society of Integrative Medicine
• /
• v.9 no.4
• /
• pp.183-190
• /
• 2021

Purpose : The purpose of this study was to investigate the effect of side planks on the muscle thickness of the core muscles, external oblique, internal oblique, and transverse abdominis, and this study was conducted to compare whether side plank exercise according to the application of various unstable support surfaces increases the thickness by activating the action of the muscles. Methods : The subjects of this study were 30 healthy adults and were randomly and equally assigned to three groups by a random number table. All subjects were divided into three groups according to the application of an unstable support surface during the side plank(Group A = stable support, Group B = one unstable support, Group C = two unstable supports). The side plank exercise was performed 30 minutes a day, 3 times a week for a total of 4 weeks. The muscle thickness of the core muscle was measured before the intervention, 2 weeks, 4 weeks, and 3 times in total. All measured data were comparatively analyzed by repeated measures ANOVA and one-way ANOVA. The statistical significance level was set to .05. Results : The results of this study were as follows : 1. All muscles showed an interaction between training period and group. 2. There was a significant difference between the groups at the 2 weeks and 4 weeks of the internal oblique and transverse abdominis muscle measurements. Conclusion : The thickness of the abdominal muscle increased during the side plank exercise according to the support surface, and the thickness of the abdominal muscle increased the most during the side plank exercise on the unstable support surface. Therefore, it is thought that the addition of an unstable support surface will provide a more effective therapeutic effect on the thickness change of the abdominal muscle during side plank exercise.

• PNF and Movement
• /
• v.17 no.2
• /
• pp.293-302
• /
• 2019

Purpose: The purpose of this study was to investigate the effects of plank exercises involving the contraction of the adductor muscle of the hip joint on core muscle thickness and to propose an effective plank exercise method. Methods: A total of 30 healthy young adults (17 males, 13 females) voluntarily participated in the study. The subjects were randomized to the prone plank exercise with hip adductor contraction (n=10), the prone plank exercise (n=10), and the supine plank exercise (n=10) groups. Muscle thickness measurements were taken prior to starting the exercise program and after completing the program at the end of a 4-week period. The muscle thickness of the rectus abdominis (RA), multifidus (MF), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) muscles were measured using ultrasonography. Each group performed the stipulated plank exercise five times a week as follows: 5 sets of 20 seconds during the first week, 5 sets of 30 seconds in the second week, 5 sets of 40 seconds in the third week, and 5 sets of 40 seconds in the last week. Results: The three different types of plank exercises all showed significantly increased thickness of the RA, MF, EO, IO, and TrA (P<0.05). Furthermore, changes in the thickness of both the MF and TrA were statistically more significant in the groups that did the prone plank exercise with the hip adductor contraction and the supine plank exercise than in the prone plank exercise group (P<0.05). Conclusion: The study results suggest that the prone plank exercise with hip adductor contraction is a more effective method for overall activation of the RA, MF, EO, IO, and TrA than the prone plank exercise and the supine plank exercise.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.3
• /
• pp.103-110
• /
• 2022

Objective: The aim of this study was to investigate effect of core stabilization exercises on the erector spinae contractile properties and trunk isokinetic muscle function of middle age with low physical activity and sedentary lifestyle. Method: Twenty (female: n=10, male: n=10) middle-age subjects (age: 37.25 ± 6.08 years, height: 168.01 ± 6.84 cm, weight: 71.37 ± 11.75 kg) participated in this study. Tensiomyography was measured on the erector spinae, and the isokinetic trunk muscle function test was measured at an angular velocity of 60 °/s and 90 °/s. All subjects performed the core stabilization exercises for 60 min per day, 3 times a week, for 7 weeks. A paired t-test was performed with a significance level of 0.05. Results: Tensiomyography of the erector spinae revealed a significant post-exercise increase in the maximum radial displacement (p < .05) and velocity of contraction (p < .05), however, there wasn't a significant post-exercise change in the contraction time. Additionally, the isokinetic muscle function test of the trunk revealed a significant post-exercise increase in trunk extensor relative strength (p < .05) and strength ratio (p < .05). Conclusion: Our results indicated that core stabilization exercises reduced erector spinae muscle stiffness, increased the velocity of erector spinae contraction. Additionally, data showed the improvement in the trunk extensor strength help induce a more balanced development in trunk muscle.

• Journal of Korean Physical Therapy Science
• /
• v.30 no.3
• /
• pp.72-83
• /
• 2023

Background: Normal-weight obese women have a normal weight with relatively low muscle mass resulting from high body fat. We aimed to investigate the effects of core exercise on body composition, abdominal muscle thickness, trunk muscular endurance, and psychological factors in normal-weight obese women. Design: One group pre-, mid-, and post-test design. Methods: A total of 20 normal-weight obese women were recruited voluntarily. Core exercises were performed for 30 minutes, three times a week for 4 weeks. InBody measurements, ultrasound imaging, and clinical tests were used to assess body composition, abdominal muscle thickness, trunk and core muscular endurance, and psychological condition(satisfaction with appearance and self-esteem). The dependent variables were measured three times: before the intervention (pre-test), 2 weeks after the intervention (mid-test), and 4 weeks after intervention (post-test). One-way repeated measures ANOVA and Friedman test were used for statistical analysis. Results: Although there was no change in the body composition (p>0.05), thickness of the transversus abdominis and internal and external oblique muscles, endurance of the trunk flexors and extensors and core muscles, and psychological condition showed significant differences after the intervention (p<0.05). Conclusion: Our findings will help develop exercise programs for normal-weight obese individuals that utilize the beneficial effect of core exercises.

• Korean Journal of Applied Biomechanics
• /
• v.27 no.4
• /
• pp.247-255
• /
• 2017

Objective: The purpose of this study was to investigate the maximum core muscle activation angle according to core-strengthening exercises. Method: Twenty-six young female football players (age: $17.84{\pm}0.80years$, height: $163.08{\pm}5.25cm$, weight: $54.96{\pm}7.41kg$) registered in the Korea Football Association from D High School located in Seoul were the subjects of this research. An electromyogram (Noraxon, USA) was used for monitoring the maximum core muscle contraction activity. Results: The angle for the maximum core muscle strength per core exercise and muscle was the smallest for the upper rectus abdominis in the windshield wiper exercise. The angle of the vastus medialis was significantly the largest. The range of angles at which the maximum strength was observed for each core exercise were as follows: 1) abdominal flutter kicks ($11{\sim}40^{\circ}$), 2) leg raises ($21{\sim}34^{\circ}$), 3) scissors ($45{\sim}66^{\circ}$), 4) knee to elbow sit-ups ($42{\sim}64^{\circ}$), 5) reverse crunches ($9{\sim}40^{\circ}$), 6) butt-ups ($24{\sim}32^{\circ}$), 7) V sit-ups ($5{\sim}24^{\circ}$), 8) windshield wipers ($11{\sim}20^{\circ}$), 9) bird dog ($11{\sim}18^{\circ}$), and 10) raised leg plank ($38{\sim}50^{\circ}$). Conclusion: Four kinds of motion could be classified according to the range of angles at which the core muscles were maximally activated. The first group involves the range of motion that gives the maximum muscle strength when the lower extremity and ground angle was between $5^{\circ}$ and $24^{\circ}$, such as the V sit-ups, windshield wipers, and bird dog. The second group comprised the flutter kicks and reverse crunches at an angle between $9^{\circ}$ and $40^{\circ}$. The third group comprised the leg raise and butt-up exercises at an angle between $21^{\circ}$ and $34^{\circ}$. The fourth group included the scissors, knee to elbow sit-ups, and raised leg plank at an angle between $38^{\circ}$ and $66^{\circ}$. These results may be useful as basic data for core movement and core muscle training according to the purpose of exercise.

• The Journal of Korean Physical Therapy
• /
• v.28 no.2
• /
• pp.112-118
• /
• 2016

Purpose: This study examined thickness changes in abdominal muscles according to difficulty level of core stabilization exercise in healthy subjects. Methods: Thirty healthy subjects (age range: 21-30 years) volunteered under three conditions. In the first condition, the subjects performed an abdominal draw-in maneuver (ADIM). In the second condition, they performed the ADIM during quadruped exercise using a suspension device without extending their lower limbs. In the third condition, the subjects performed the ADIM during quadruped exercise using a suspension device while extending both lower limbs. The changes in thickness of transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) muscles were measured by ultrasonography (US) imaging during the three experimental conditions, and US was used to measure the improvement ratio of muscle thickness at rest. The interventions were conducted over three trials in each condition, and measurements were performed on each subject by one examiner. Results: Our results showed a significantly greater increase in the muscle thickness of TrA and IO muscles after performance of quadruped exercise using a suspension device without knee extension (p<0.05) compared to the other conditions. The results also showed a significantly greater increase in the thickness changes of EO muscle in those who performed the ADIM during quadruped exercise using a suspension device with knee extension (p<0.05) compared with the ADIM only. Conclusion: These findings demonstrated positive evidence that a low-level core stabilization exercise could improve thickness of abdominal muscles.

• Journal of The Korean Society of Integrative Medicine
• /
• v.8 no.1
• /
• pp.67-76
• /
• 2020

Purpose : The purpose of this study was to provide more effective interventions for elderly men with weak core muscles by measuring the thickness of the muscles according to the five core stabilization exercise and comparing the thickness differences in muscles in each posture. Methods : The study selected 29 elderly men aged 65 to 80 years old among outpatient patients at S Medical Center in B city, and measured the muscle thickness by exercise posture once. In order to find out the thickness of the external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) muscles were measured by using rehabilitative ultrasound imaging (RUSI) in five exercise conditions. Results : A significant change in the thickness of the EO muscles in each group was measured by the method of motion, followed by the abdominal crunches (1.67±0.15), the lower body rotations (1.54±0.07). As a result of measuring the thickness of the IO muscles of each group according to the exercise method, the bridge group (1.14±0.22) was the highest, followed by the abdominal drawing group (1.05±0.03). As a result of measuring the thickness of the TrA muscles of each group according to the exercise method, the abdominal crunches (0.98±1.00) were the highest, and the bridge group (0.57±0.05) were higher in order of magnitude. Conclusion : Consequently, the five core stabilization exercises all affect changes in abdominal thickness and are expected to continue to require training studies on muscle posture.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.1425-1426
• /
• 2015

Core spine muscle are related are associated with trunk stability and play a main role for the prevention of low back pain. In this study, it was investigated the effect of spine stabilization exercise device on core spinal muscles using a musculoskeletal model The forward direction of the tilt mainly induced the activation of long and superficial back muscles and the backward affected the front muscles. It was shown that spine stabilization exercise device can induce significant core muscle exercise effect.