• 수산해양교육연구
• /
• 제28권4호
• /
• pp.893-902
• /
• 2016

The purpose of this study is to investigate the effect of wearing a weightlifting belt, which is an auxiliary equipment used during squat, by measuring and analyzing biomechanical difference in lower limb and proposing safer and to suggest a more effective exercise method for general population. Selected 8 male participants in their 20s who have not performed regular resistance exercise for at least a year, but have experience of performing squat. The comprehensive method of study is as follows: subjects were notified of the purpose of the study and were told to practice warm-up and the squat motion for the experiment for 20 minutes. When the participant believed they were ready to begin, the experiment was started. At controlled points, foot pressure distribution sensor has been installed. Then left and right feet have been placed on the pressure distribution sensor, from which data for successful squat position that does not satisfy the criteria for failure have been collected and computed with Kwon3D XP program and TPScan program. For data processing of this study, SPSS 21.0 was used to calculated mean (M) and standard deviation (SD) of the analyzed values, and paired t-test has been conducted to investigate the difference before and after wearing the weightlifting belt, with p-value of ${\alpha}<.05$. As for time consumed depending on usage of weightlifting belt in squat, statistically significant difference has been found in P2, which is recovery movement. Lower limb angle depending on usage of weightlifting belt in squat has shown statistically significant difference in E1 foot joint(p<. 001). There has been statistically significant difference in E2 knee joint. Foot pressure percentage depending on usage of weightlifting belt in squat were found to be statistically significant (p<. 01) in both regions of anterior and posterior foot.

• 대한인간공학회지
• /
• 제30권3호
• /
• pp.409-418
• /
• 2011

Objective: This study was performed to evaluate the child-care teachers' job in relation to physical work. Background: Child-care teacher is directly related to the quality of child care. And their physical activity is higher than general education teachers because the proportion of day care is high. But analyzes of child-care teachers' job burdens and the work environment associated with physical activity is not well established. Method: To conduct this study, the child-care teachers' job was classified into 18 physical works. After classification, posture was evaluated by ergonomic posture evaluation schemes of OWAS, RULA, REBA and evaluated for each physical part. Next, musculoskeletal subjective symptoms were analyzed. Results: The results showed the following: The highest assessment on the posture evaluation was "helping children to ride a school bus", "feeding: meal/snack", "brushing children's teeth" and "arrangement of nap-stuff". The rank of high-risk assessment on the neck/trunk/leg part was arranged by: "feeding: meal/snack", "helping children to ride a school bus", "making nap", "arrangement nap-stuff" and "brushing children's teeth". The rank of high-risk assessment on the upper limbs part was arranged by: "helping children to ride a school bus", "the bust - group activity", "meal/snack time - preparing, feeding, arrangement", "nap time - preparing, arrangement", "brushing children's teeth", and "using the toilet". According to the results of each musculoskeletal subjective symptom, teachers ordered the pain area as follows: waist, shoulder, leg/feet, and neck, and they showed more pain on trunk than the upper limbs. Conclusion: To sum up the results from ergonomic posture evaluation and a subjective symptom, the following are high working pressures: "feeding: meal/snack", "the bust - group activity", "making nap", "brushing children's teeth" with deep bending and waist twisting, "helping children to ride a school bus", "brushing children's teeth" with lifting shoulder; "meal/snack time - preparing, arrangement", "nap time - preparing, arrangement", and "using the toilet" with moving or an up-down position in their job. Application: The results of this study might be information for improvement of the child-care teachers' job environment.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
• /
• 제16권11호
• /
• pp.1131-1135
• /
• 2010

본 논문에서는 고정시킨 평면거울을 바라보는 단일 카메라에서 얻어진 영상을 이용하여 훈련자 양 하지의 자세를 3차원으로 추정하는 방법을 제안한다. 이를 위해, 카메라 입력영상으로부터 평면거울에 부착된 네 개의 적외선 마커를 탐색하여 단일 카메라의 자세를 추정한다. 추정된 카메라 자세를 통해 거울평면을 기준으로 하는 훈련공간을 정의하고, 압력 센서를 사용하여 공간 내의 훈련자의 양 하지 위치를 측정한다. 양 하지의 마커는 직접적으로, 또는 거울을 통해 카메라 영상으로 투영되고, 정의된 훈련 공간에서 3차원 위치로 변환된다. 변환된 마커들의 3차원 위치관계에 의해 최종적으로 양 하지의 자세를 얻고 연속적인 움직임에 대해 운동 상태를 추정한다.

• 한국운동역학회지
• /
• 제23권3호
• /
• pp.209-218
• /
• 2013

This study was to perform the kinetic analysis of forward $1\frac{1}{2}$ somersault on the platform diving. Six men's diving players of the Korea national reserve athletes participated in this study. The variables were analyzed response time, velocity, center of mass (COM), angle, center of pressure (COP) and ground reaction force (GRF) of motion. For measure and analysis of this study, used to synchronized to 4 camcorder and 1 force plate, used to the Kwon3D XP (Ver. 4.0, Visol, Korea) and Kwon GRF (Ver. 2.0, Visol, Korea) for analyzed of variables. The results were as follows; Time factor were observed in maximum knee flexion depending on the extent of use at phase 1 of take-off to execute the somersault. This enabled the subject to secure the highest possible body position in space at the moment of jumping to execute the somersault and prepare for the entry into the water with more ease. Regarding the displacement of COM, all subjects showed rightward movement in the lateral displacement during technical execution. Changes in forward and downward movements were observed in the horizontal and vertical displacements, respectively. In terms of angular shift, the shoulder joint angle tended to decrease on average, and the elbow joints showed gradually increasing angles. This finding can be explained by the shift of the coordinate points of body segments around the rotational axis in order to execute the half-bending movement that can be implemented by pulling the lower limb segments toward the trunk using the upper limb segments. The hip joint angles gradually decreased; this accelerated the rotational movement by narrowing the distance to the trunk. Movement-specific shifts in the COP occurred in the front of and vertical directions. Regarding the changes in GRF, which is influenced by the strong compressive load exerted by the supporting feet, efficient aerial movements were executed through a vertical jump, with no energy lost to the lateral GRF.

• Composites Research
• /
• 제34권3호
• /
• pp.161-166
• /
• 2021

본 연구에서는 당뇨병 환자들의 균일한 족압 분포를 유도하여 발의 상처를 예방하는 신발을 개발하기 위한 연구방법을 제시하였다. 직교 그리드 센서를 사용하여 일반인의 직립 상태 시 족압 분포를 확인하고, 다양한 조건에 대한 족압분포의 변화를 비교하였다. 신발 바닥부에 삽입된 스프링의 스프링 상수와 인솔의 아치부 유무 등에 따른 족압 분포의 변화를 파악하여 효과적인 족압 분산 조건을 확인하였다. 인체거동의 임의성 등에 의한 실험 오차를 최소화 하기 위해, 직립 상태를 모사한 유한요소해석을 통해 특정 조건에서의 족압 분포를 예측하고 실험 결과와 비교하여 실험의 정확성을 확보할 수 있도록 하였다. 스프링의 개수와 배치에 따른 족압 분포의 변화를 유한요소해석을 통해 확인하여 보다 균일한 족압을 구현할 수 있는 조건을 제시하였다. 이러한 결과는 당뇨발을 가진 환자를 위한 신발 설계에 활용할 수 있을 것으로 기대된다.

• 대한통합의학회지
• /
• 제9권1호
• /
• pp.133-140
• /
• 2021

Purpose: This study aimed to compare the relative muscle activity on the erector spinae, gluteus maximus, and hamstring, using a non-visual feedback bridge exercise and a visual feedback bridge exercise with a tension sensor and clinometer. Methods: Twenty-two healthy subjects participated in this study. The study subjects performed bridge exercises without visual feedback, bridge exercises using a tension sensor, and bridge exercises using an inclinometer in the supine position, and the muscle activity of the left and right erector spinae, gluteus maximus, and hamstring muscles was measured while maintaining isometric contraction during the bridge movement. Muscle activity was measured by using surface an electromyography equipment. To standardize the measured action potential of each muscle, the maximum voluntary isometric contraction was measured. The bridge exercise was repeated 3 times for 5s each. Using repeated analysis of variance, we compared the significant difference in EMG activity for each muscle between the three experiments, and all statistical processing was performed using SPSS version 26. The statistical significance level was set at α = 0.05. Results: During bridging exercises, the asymmetry of the muscle activity of the erector spinae and gluteus maximus during visual feedback guiding was lower than that during no visual feedback. However, there was no significant difference. Moreover, the asymmetry of the muscle activity of the hamstring muscles was significantly lower during tension sensor visual feedback than that during no visual feedback (p<0.05). Conclusion: These findings suggest that bridge exercise with visual feedback using a tension sensor and an inclinometer is effective in inducing symmetrical movement. When it is necessary to symmetrically adjust the weight load of both feet during the bridge exercise, it is effective to apply visual feedback using a tension sensor.

• The Journal of Korean Physical Therapy
• /
• 제35권2호
• /
• pp.48-52
• /
• 2023

Purpose: This study was undertaken to determine whether the position of cane use affects the distribution of weight-bearing on both feet of children with hemiplegic cerebral palsy in a standing posture. Methods: Twenty participants with cerebral palsy were recruited as volunteers for this study. Using the Zebris FDM-System, weight-bearing distribution according to the method of using a cane was measured under three conditions in randomized order: (1) standing unaided (no cane); (2) standing with the affected side using the cane; and (3) standing with the non-affected side using the cane. The cane was matched by measuring length-from-floor to the greater trochanter of the subject, and was placed 15 cm outward from the little toe on the supporting side. Results: Evaluating the method of using a cane under the three conditions, we determined that pressure of the foot on the affected side was higher in the order: standing with affected side using cane > standing unaided (no cane) > standing with non-affected side using cane (p<0.05). In the post-hoc analysis, a significant difference was observed between (i) standing unaided (no cane) and standing with the affected side using cane, and (ii) standing with affected side using cane and standing with non-affected side using cane (p<0.05). Conclusion: This study suggests that induced weight-bearing methods using a cane on the affected side could increase the weight-bearing capacity on the affected side in children with spastic hemiplegic cerebral palsy, which will have a positive effect on reducing asymmetry weight support.

• 한국운동역학회지
• /
• 제17권2호
• /
• pp.177-185
• /
• 2007

Even though there were no clear definitions of the short game and short game distance, short game capability is crucial for a good golf score. Generally, chip shot and pitch shot are regarded as two principal components of the short game. Chip shot is a short, low trajectory shot played to the green or from trouble back into play. Pitch shot is a high trajectory shot of short length. Biomechanical studies were conducted usually to analyze full swing and putting motions. The purpose of the study was to reveal the kinematical differences between professional golfers' 30 yard $53^{\circ}wedge$ chip shot and $56^{\circ}wedge$ pitch shot motions. Fifteen male professional golfers were recruited for the study. Kinematical data were collected by the 60 Hz three-dimensional motion analysis system. Statistical comparisons were made by paired t-test, ANOVA, and Duncan of the SPSS 12.0K with the $\alpha$ value of .05. Results show that both the left hand and the ball were placed left of the center of the left and right foot at address. The left hand position of the chip shot was significantly left side of that of the pitch shot. But the ball position of the pitch shot was significantly right side of that of the chip shot. All body segments aligned to the left of the target line, open, at address. Except shoulder, there were no significant pelvis, knee, and feet alignment differences between chip shot and pitch shot. These differences at address seem for the ball height control. Pitch shot swing motions(the shoulder and pelvis rotation and the club head travel distance) were significantly bigger than those of the chip shot. Club head velocity of the pitch shot was significantly faster than that of the chip shot at the moment of impact. This was for the same shot length control with different lofted clubs. Swing motion differences seem mainly caused by the same shot length control with different ball height control.

• 한국의상디자인학회지
• /
• 제11권2호
• /
• pp.183-195
• /
• 2009

In this study, foot shapes were compared between the men in their 20's and 60's, with the application of 3-dimensional measurement data, and the classification was established in consideration of each of their features. The results are as follows: 1. The investigation into the differences between the groups for the 3-dimensional measurement items of the men in their 20's and 60's indicated that those in their 20's had larger values than those in the 60's age group for all of the length items, while those in the 60's age group had larger values for all of the angle items. 2. The analysis of the constituting factors for the feet of those in their 60's and 20's resulted in the 7 items for the 20's age group and 8 items for those in the 60's age group. 3. The comparison of foot classifications for the 60's age group and 20's age group presented 3 types each for both groups, but the features of each type was different. To examine each characteristic by each type and age group, following can be determined of the 60's age group. Type 1 had a thick instep, high malleolus position and heel and a thick formed ankle. Type 2 the entire foot was small, and the big toe was formed in such a way that it tened to bend toward the inside. When the whole size compared with similar Type 1, Type 3 had a low instep, a low heel, the big toe did not bend and ankle form was thin. The following can be determined of the 20's age group. Type 1 had narrow width a thin ankle and the big toe was formed in such a way that it bended toward the inside. Compared with length, Type 2 had wide width and a thick ankle. Type 3 had a larger overall size, thick instep and wide and the toe was big, but the characteristic of inside and outside of a malleolus position was low and the big toe's form showed no tendencies to bend.

• 대한족부족관절학회지
• /
• 제15권2호
• /
• pp.68-71
• /
• 2011

Purpose: To analyze relation between age or parameters measured before operation and cartilage erosion of the first metatarsal head measured during operation. Materials and Methods: The study was targeted at 56 patients and 79 feet, who underwent Scarf osteotomy or Scarf and Akin osteotomy from November 2009 through November 2010, and whose cartilage lesion of the first metatarsal head referred to the cartilage grade III or IV of the International Cartilage Repair Society. The measurement parameters were age, hallux valgus angle, intermetatarsal angle (1~2), tibial sesamoid position, proximal articular set angle and distal articular set angle. The cartilage erosion of the first metatarsal head was measured by one surgeon using cellophane. Occupancy rate and frequent involved sites of the cartilage erosion were recorded using Auto$CAD^{(R)}$ and adobe Illustrator CS4 program. SPSS correlation test and T-test were used for statistical analysis of the parameters and the cartilage erosion. Results: The cartilage erosion was incurred frequently in the sagittal groove and the site where subluxation or dislocation of the tibial sesamoild bone occurred but frequent involved sites had no statistical significance with cartilage erosion. The age showed a statistical significance with the cartilage erosion in the correlation test (p=0.003). Especially, the group of over 51 year old patients was turned out to have association with the cartilage erosion, compared to the group of below 51 (p=0.007). But, hallux valgus angle, intermetatarsal angle (1~2), tibial sesamoid position, proximal articular set angle and distal articular set angle were no statistical significance with the cartilage erosion. Conclusion: We found the more the age of patients increased (especially above 51), the more cartilage erosion increased. And it is thought that we pay attention to reduce tibial sesamoid bone.