• 한국산학기술학회논문지
• /
• 제20권7호
• /
• pp.380-386
• /
• 2019

어깨관절 통증은 성인의 약 20% 정도가 일생에 한 번 이상 경험하는 매우 흔한 근골격계 질환이다. 이에 본 연구에서는 작은가슴근 신장운동에 의해 어깨뼈봉우리 밑 공간이 증가하여 충돌증후군 및 어깨통증에 긍정적인 효과가 있다는 객관적 평가를 실시하고, 작은가슴근 자가 신장운동이 도수 신장운동과 비교하여 작은가슴근의 길이와 봉우리 위팔 거리에 미치는 영향을 알아보고자 실시하였다. 경상북도 소재의 대학교에서 성인 남녀 30명을 대상으로 하여 대상자가 스스로 작은가슴근 자가 신장운동을 실시하는 실험군 15명과 치료사에 의해 수행되는 작은가슴근 도수 신장운동을 적용한 대조군 15명으로 두 그룹을 무작위 배치하여 치료의 즉각적인 효과를 비교하였다. 어깨뼈봉우리 위팔 거리를 측정하기 위해 초음파 장비를 사용하였고, 작은가슴근 길이를 측정하기 위해 4번째 늑골과 복장뼈가 만나는 부위 그리고 오훼돌기 아래측면 사이의 거리를 재었다. 연구결과 실험군과 대조군 모두 그룹 내에서 작은가슴근의 길이와 봉우리 위팔 거리 모두 유의하게 증가되었고(p<.05), 그룹 간 비교에서는 통계학적으로 유의한 차이가 나타나지 않았다(p>.05). 이러한 결과는 작은가슴근의 자가 신장운동이 충돌증후군 및 어깨질환의 예방 및 치료에 효율적인 운동방법으로 제시될 수 있다고 사료된다.

• 한국엔터테인먼트산업학회논문지
• /
• 제14권6호
• /
• pp.301-309
• /
• 2020

본 연구는 4주간 테이핑을 병행한 스위스 볼 운동이 임신성 요통환자의 통증과 기능장애 및 삶의 질에 미치는 효과를 규명하기 위하여 실시되었다. 단일 맹검 및 사전 무작위 임상시험으로 진행되었으며, 16명의 임신성 요통 환자는 무작위로 테이핑과 스위스 볼 운동군(n=8)과 테이핑과 신장 운동군(n=8)으로 배정되었다. 모든 대상자는 허리에 테이핑을 적용하였다. 추가적으로 테이핑과 스위스 볼 운동군은 스위스 볼 운동을 하루 30분, 주 5회, 4주간 시행하였고 테이핑과 신장 운동군은 같은 시간동안 스트레칭 운동을 적용하였다. 통증은 시각사상척도(VAS)를 사용하여 측정하였고, 기능장애는 Roland Morris Disability Questionnaire (RMDQ), 삶의 질은 Short-Form 36 items (SF-36)을 사용하였다. 훈련 후 테이핑과 스위스 볼 운동군이 테이핑과 신장 운동군에 비해 통증과 기능장애, 삶의 질이 유의하게 개선되었다(p<.05). 본 연구는 테이핑을 병행한 스위스 볼운동이 임산부의 요통과 기능장애 및 삶의 질을 효과적으로 향상시킴을 증명하였다.

• Smart Structures and Systems
• /
• 제19권2호
• /
• pp.115-126
• /
• 2017

In this paper, size dependent bending and free flexural vibration behaviors of functionally graded (FG) nanobeams are investigated using a nonlocal quasi-3D theory in which both shear deformation and thickness stretching effects are introduced. The nonlocal elastic behavior is described by the differential constitutive model of Eringen, which enables the present model to become effective in the analysis and design of nanostructures. The present theory incorporates the length scale parameter (nonlocal parameter) which can capture the small scale effect, and furthermore accounts for both shear deformation and thickness stretching effects by virtue of a hyperbolic variation of all displacements through the thickness without using shear correction factor. The material properties of FG nanobeams are assumed to vary through the thickness according to a power law. The neutral surface position for such FG nanobeams is determined and the present theory based on exact neutral surface position is employed here. The governing equations are derived using the principal of minimum total potential energy. The effects of nonlocal parameter, aspect ratio and various material compositions on the static and dynamic responses of the FG nanobeam are discussed in detail. A detailed numerical study is carried out to examine the effect of material gradient index, the nonlocal parameter, the beam aspect ratio on the global response of the FG nanobeam. These findings are important in mechanical design considerations of devices that use carbon nanotubes.

• Wind and Structures
• /
• 제27권4호
• /
• pp.269-282
• /
• 2018

In this paper, a new displacement field based on quasi-3D hybrid-type higher order shear deformation theory is developed to analyze the static and dynamic response of exponential (E), power-law (P) and sigmoïd (S) functionally graded beams. Novelty of this theory is that involve just three unknowns with including stretching effect, as opposed to four or even greater numbers in other shear and normal deformation theories. It also accounts for a parabolic distribution of the transverse shear stresses across the thickness, and satisfies the zero traction boundary conditions at beams surfaces without introducing a shear correction factor. The beam governing equations and boundary conditions are determined by employing the Hamilton's principle. Navier-type analytical solutions of bending and free vibration analysis are provided for simply supported beams subjected to uniform distribution loads. The effect of the sigmoid, exponent and power-law volume fraction, the thickness stretching and the material length scale parameter on the deflection, stresses and natural frequencies are discussed in tabular and graphical forms. The obtained results are compared with previously published results to verify the performance of this theory. It was clearly shown that this theory is not only accurate and efficient but almost comparable to other higher order shear deformation theories that contain more number of unknowns.

• 대한물리의학회지
• /
• 제12권4호
• /
• pp.83-92
• /
• 2017

PURPOSE: The purpose of this study was to investigate the effect of the elastic band and stretching exercise program on ankle joint maximal voluntary isometric contraction (MVIC) and plantar pressure in high-heel wearing women in their 20s. METHODS: Twenty women in their twenties were randomly assigned to the experimental group (n=10) and the control group (n=10). The experimental group (n=10) performed the elastic band exercise program, while the control group (n=10) performed the stretching exercise program. Both exercise programs were performed three times a week for a total of four weeks. The BTE Primus RS was used in order to measure the ankle joint MVIC during dorsiflexion, plantar flexion, inversion, and eversion. Maximum pressure ($N/cm^2$), average pressure ($N/cm^2$) were measured using the Pedoscan. SPSS v. 21.0 software was used for all statistical analyses in this study. RESULTS: The measurement of the ankle joint's MVIC revealed that in inversion, a significant change in both feet was seen in both the experimental and control groups. In eversion, there was a significant change in both feet only in the experimental group. In terms of the rest of the results, no significant changes were visible. With regard to the plantar pressure, no significant results were seen for either foot in the comparison between or within the groups. CONCLUSION: Exercise program using elastic band and exercise program using stretching were effective on MVIC of ankle joint muscles, although it had no effect on changes of plantar pressure.

• Structural Engineering and Mechanics
• /
• 제75권2호
• /
• pp.193-209
• /
• 2020

This paper presents a new hyperbolic shear deformation plate theory including the stretching effect for free vibration of the simply supported functionally graded plates in thermal environments. The theory accounts for parabolic distribution of the transverse shear strains and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. This theory has only five unknowns, which is even less than the other shear and normal deformation theories. The present one has a new displacement field which introduces undetermined integral variables. Material properties are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume power laws of the constituents. The equation of motion of the vibrated plate obtained via the classical Hamilton's principle and solved using Navier's steps. The accuracy of the proposed solution is checked by comparing the present results with those available in existing literature. The effects of the temperature field, volume fraction index of functionally graded material, side-to-thickness ratio on free vibration responses of the functionally graded plates are investigated. It can be concluded that the present theory is not only accurate but also simple in predicting the natural frequencies of functionally graded plates with stretching effect in thermal environments.

• Physical Therapy Rehabilitation Science
• /
• 제13권1호
• /
• pp.36-42
• /
• 2024

Objective: The aim of this study is to investigate the effect of hamstring eccentric exercise on pain and functional activity in patients with chronic low back pain. Design: Randomized controlled trial Methods: Participants comprised 27 subjects with back pain persisting for 3 months. They were randomly assigned to the experimental group (Eccentric exercise: n=13) and the control group (Stretching: n=14). The experimental group performed gastrocnemius, iliopsoas, and quadratus lumborum stretching along with hamstring eccentric exercise, while the control group engaged in the same stretches along with hamstring stretching. The eccentric exercise for the hamstrings was Nordic curl exercise. Each group practiced for 1 hour a day, 3 times a week, for 4 weeks. Pain, disability index, balance, and hamstring length were measured. Results: Significant differences were observed in the comparison of changes in back pain, back disability index, and hamstring length before and after exercise within each group (p<0.05). The balance ability of the experimental group showed a difference before and after exercise (p<0.05), whereas no significant difference in the control group. There were no significant differences in back pain and hamstring length between the groups. Changes in back disability index and balance ability significantly increased in the experimental group compared to the control group (p<0.05). Conclusion: Hamstring eccentric exercise using Nordic curls has a positive effect on back pain, back disability index, balance ability, and hamstring length changes.

• Structural Engineering and Mechanics
• /
• 제66권1호
• /
• pp.61-73
• /
• 2018

In this article, a higher shear deformation theory (HSDT) is improved to consider the influence of thickness stretching in functionally graded (FG) plates. The proposed HSDT has fewer numbers of variables and equations of motion than the first-order shear deformation theory (FSDT), but considers the transverse shear deformation influences without requiring shear correction coefficients. The kinematic of the present improved HSDT is modified by considering undetermined integral terms in in-plane displacements and a parabolic distribution of the vertical displacement within the thickness, and consequently, the thickness stretching influence is taken into account. Analytical solutions of simply supported FG plates are found, and the computed results are compared with 3D solutions and those generated by other HSDTs. Verification examples demonstrate that the developed theory is not only more accurate than the refined plate theory, but also comparable with the HSDTs which use more number of variables.

• 대한물리치료과학회지
• /
• 제26권1호
• /
• pp.15-21
• /
• 2019

Background: The purpose of this study was to the effects of stretching on lumbar flexibility after lumbar and lower muscle strengthening exercise. Design: Randomized Controlled Trial. Methods: 24 subjects without back pain in their twenties were divided into 12 experimental groups and 12 control groups. The experimental group performed a stretching program after muscle strength exercise. In the control group, only muscle strength exercise was performed, and total exercise was performed 24 times a week for 8 weeks to compare and analyze before and after experiment. Results: The results of this study are as follows: 1) There was no statistically significant difference in both before and after weight of experimental group and control group. 2) There was no statistically significant difference in both before and after skeletal muscle levels of experimental group and control group. 3) There was no statistically significant difference in both before and after fat mass of experimental group and control group. 4) There was a statistically significant difference in both before and after trunk forward flexion of experimental group and control group. Conclusion: This research showed a positive affect on increasing flexibility, which is expected to have a great effect on improvement of flexibility in the future.

• 대한물리의학회지
• /
• 제16권3호
• /
• pp.55-64
• /
• 2021

PURPOSE: The purpose of this study was to apply dynamic neuromuscular stabilization (DNS) to subjects with forward head posture (FHP) and to compare its effects on respiratory function as against the conventional neck stabilization exercise and neck stretching and extensor strengthening exercises. METHODS: The whole-body posture measurement system was used to measure the degree of FHP, and a spirometer and a respiratory gas analyzer were used to measure the respiratory function. After the intervention was completed, the changes over time were analyzed in the DNS group, the neck stabilization exercise group, and the neck stretching and extensor strengthening exercise group. The inter-group difference in the changes was also analyzed. A repeated ANOVA was performed to compare the respiratory function according to the period between the three groups, and the least significant difference (LSD) method was used for the post hoc test. RESULTS: After the 6-week exercise period, respiratory functions, such as forced vital capacity (FVC), forced expiratory volume for 1 second (FEV1), forced expiratory volume for 1 sec/forced vital capacity (FEV1/FVC), maximum oxygen intake (VO₂max), and the volume of expired gas (VE), significantly improved according to the period (p < .05), but no inter-group differences were found. CONCLUSION: DNS is an effective training method, and can be applied along with neck stabilization exercise and neck stretching and extensor strengthening exercises, which are widely used in clinical practice, to people with FHP who cannot directly perform neck exercises to improve their respiratory function.