Effect of wearing a knee brace or sleeve on the knee joint and anterior cruciate ligament force during drop jumps: A clinical intervention study

Moon, Jeheon,Kim, Hyeyoung,Lee, Jusung,Panday, Siddhartha Bikram Elsevier 2018 The knee Vol.25 No.6

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>Knee braces are considered to be extremely useful tools in reducing the shear force of knee joints for non-contact anterior cruciate ligament (ACL) injury prevention. However, the effectiveness of sports knee braces and sleeves remains to be identified. Therefore, the purpose of this study was to evaluate the effectiveness of wearing commercialized sports knee braces and sleeves on knee kinematics, kinetics, and ACL force during drop jumps using musculoskeletal modeling analysis.</P> <P><B>Methods</B></P> <P>Musculoskeletal modeling analysis was conducted on 19 male alpine skiers who performed drop jump motions from a 40-cm box under three conditions: without a brace/sleeve, with a brace, and while wearing a neoprene sleeve.</P> <P><B>Results</B></P> <P>The physical performance (i.e., the center of mass of the jumping height) was not affected by the type of brace or sleeve. However, wearing a brace or sleeve during drop jump tasks reduced the knee joint's maximum flexion, abduction angles, and adduction moment. The knee joint shear force when wearing the brace or sleeve exhibited no statistical differences. Further, the ACL load estimated in this study did not exhibit any statistical differences in relation to wearing a brace or sleeve.</P> <P><B>Conclusions</B></P> <P>The knee braces and sleeves reduced flexion and abduction movement, and adduction moment but did not reduce the knee joint shear force, internal rotation moment, or the ACL force. Therefore, if a sports knee brace that controls the knee joint's shear force and internal rotation moment is developed, it may aid in preventing ACL injuries.</P>

The Effect of Shoulder Flexion Angles on the Recruitment of Upper-extremity Muscles during Isometric Contraction

Moon, Jeheon,Shin, Insik,Kang, Myoungsoo,Kim, Yeonghun,Lee, Kunwoo,Park, Jaewoo,Kim, Kyungnam,Hong, Daehie,Koo, Dohoon,O'sullivan, David The Society of Physical Therapy Science 2013 JOURNAL OF PHYSICAL THERAPY SCIENCE Vol.25 No.10

<P> The purpose of this study was to investigate the differences in muscle activation patterns of the biceps brachii (BB) and flexor carpi radialis (FCR) muscles, while measuring the resultant force (RF) at different shoulder flexion angles. [Subjects] Thirteen healthy males (age 24.85±3.4 years, weight; 77.8±7.9 kg; height, 1.7±0.05 m) were enrolled in this study. [Methods] The resultant force was measured by a force transducer . The elbow angle remained constant and the flexion shoulder angle was changed (30°, 45°, 60°, 75° and 90°). [Results] The results of the surface EMG show the largest muscle activities occurred at a shoulder flexion of 75° for BB and 90° for FCR. The largest resultant force was measured at a shoulder flexion angle of 75°. We conclude, that when performing the biceps curl exercise using an arm curl machine, the shoulder should be flexed at 75° to maximize the focus of the exercise for the BB. [Conclusion] These results are useful from the perspective of design as they highlight the differences in the muscle activation of BB and FCR with postural change. Ultimately this knowledge can be used in the design of rehabilitation training for the shoulder as they show that posture can affect muscle activation.</P>

Effect of ski simulator training on kinematic and muscle activation of the lower extremities

Moon, Jeheon,Koo, Dohoon,Kim, Kitae,Shin, Insik,Kim, Hyeyoung,Kim, Jinhae The Society of Physical Therapy Science 2015 JOURNAL OF PHYSICAL THERAPY SCIENCE Vol.27 No.8

<P>[Purpose] This study aimed to verify the effectiveness of an augmented reality-based ski simulator through analyzing the changes in movement patterns as well as the engagement of major muscles of the lower body. [Subjects] Seven subjects participated in the study. All were national team-level athletes studying at “K” Sports University in Korea who exhibited comparable performance levels and had no record of injuries in the preceding 6 months (Age 23.4 ± 3.8 years; Height 172.6 ± 12.1 cm; Weight 72.3 ± 16.2 kg; Experience 12.3 ± 4.8 years). [Methods] A reality-based ski simulator developed by a Korean manufacturer was used for the study. Three digital video cameras and a wireless electromyography system were used to perform 3-dimensional motion analysis and measure muscle activation level. [Results] Left hip angulation was found to increase as the frequency of the turns increased. Electromyography data revealed that the activation level of the quadriceps group’s extension muscles and the biceps femoris group’s flexing muscles had a crossing pattern. [Conclusion] Sustained training using an augmented reality-based ski simulator resulted in movements that extended the lower body joints, which is thought to contribute to increasing muscle fatigue.</P>

Anterior Cruciate Ligament Injury is Unlikely to Occur when Performing a Stable Weight Lifting Operation

Moon, Youngjin,Moon, Jeheon Korean Society of Sport Biomechanics 2018 한국운동역학회지 Vol.28 No.4

Objective: The purpose of this study was to examine the effect of increase in barbell weight on closely related variable to the anterior cruciate ligament (ACL) injury which are knee joint kinematics, joint load, joint moment, and maximum load attainment point during snatch of the weight lifting. Method: The subjects of the study were 10 male Korean national weight lifting athletes (69 kg 5, 77 kg 5; age: $21.80{\pm}3.91yrs.$, height: $168.00{\pm}4.06cm$, weight: $75.00{\pm}4.02kg$, career: $7.8{\pm}3.99yrs.$, snatch records: $168{\pm}4.06kg$). The weight of the barbell during the snatch operation was set at 70%, 75% and 80% of the highest records for each subject studied. Results: The result obtained from the one-way repeated measure ANOVA are as follows: With increased barbell weight, the extension moment of the left knee joint was higher in the 80% condition than the 70% (p<.001). However, other variables were not statistically significant difference. According to the factor analysis of the variables related to maximum load attainment point of the ACL major injury variables, the first sub-factor was the internal shear force, the posterior shear force, the abduction moment, and the muscle activity of the VL. The second sub-factor was the extension moment of the knee joint, compressive force, adduction moment, and the third sub-factor was the muscle activity of BF. Conclusion: These results indicate that the possibility of ACL injury can be lowered when performing a stable snatch movement.

LTV 규제의 금융기관 경영건전성 효과 분석

문제헌(Moon, Jeheon),김갑열(Kim, Gabyoul) 한국경제연구원 2015 규제연구 Vol.24 No.1

우리나라 LTV 규제정책은 금융기관 경영건전성 유지 목적으로 2002년에 도입되었다. LTV 규제근거인 금융위원회 고시에도 이를 명시하고 있다. 그러나 LTV 제도는 규제비율 강화 또는 완화를 통해 부동산시장 등 경기조절수단으로 활용되고 있는 실정이다. 본 연구는 LTV 제도 도입 13년이 경과한 시점에서 동 규제가 본래의 도입 목적에 부합하게 운영해왔는지를 실증분석을 통해 확인해 보았다. 분석 결과 LTV 규제 완화는 오히려 금융기관 경영건전성 지표인 고정이하여신비율과 자기자본비율을 개선시키는 것으로 나타났다. 이는 LTV 규제를 강화하면 반대로 금융기관 경영건전성이 악화된다는 의미이다. 이러한 역설적 현상은 LTV 규제 강화(또는 완화)로 대출이 감소(또는 증가)하면서 금융기관 경영건전성에 역의 방향으로 영향을 미치기 때문이다. 한편 LTV 규제는 한국은행 정책변수인 통화량과 금리에는 정의 방향으로 영향을 주고 상당한 설명력을 보유한 것으로 확인되었다. 이는 현행 LTV 규제정책의 거버넌스를 재정비할 필요가 있음을 시사한다. The LTV regulatory policy was adopted for improving asset soundness of financial institutions by FSC in 2002. Administrative rule made by FSC also states that aims. But, it is a current picture to use tightening or easing the LTV regulation as an instrument which affects macro economy at large as well as real estate sector. The purpose of this study is to check up on coinciding with aims in statute and operation of reality through empirical analysis at this time over 13 years after bringing in the regulation system. It proved that easing the LTV regulation affects improving a soundness indicator of banking institutions, NPL ratio and BIS ratio, on the contrary. It means on other way that tightening the LTV regulation brings about lowering the soundness. Those paradoxical phases comes from reverse effect that tightening(or easing) of the regulation causes decreasing(or increasing) loans each. On the other hand, it affected the policy variables of central bank, total currencies and interest rate, normally. Further more it has a significant description capacity. These results implies that it is necessary to rebuild regulatory governance of LTV policy.

Anterior Cruciate Ligament Injury is Unlikely to Occur when Performing a Stable Weight Lifting Operation

( Youngjin Moon ),( Jeheon Moon ) 한국운동역학회 2018 한국운동역학회지 Vol.28 No.4

Objective: The purpose of this study was to examine the effect of increase in barbell weight on closely related variable to the anterior cruciate ligament (ACL) injury which are knee joint kinematics, joint load, joint moment, and maximum load attainment point during snatch of the weight lifting. Method: The subjects of the study were 10 male Korean national weight lifting athletes (69 kg 5, 77 kg 5; age: 21.80±3.91 yrs., height: 168.00±4.06 cm, weight: 75.00±4.02 kg, career: 7.8±3.99 yrs., snatch records: 168± 4.06 kg). The weight of the barbell during the snatch operation was set at 70%, 75% and 80% of the highest records for each subject studied. Results: The result obtained from the one-way repeated measure ANOVA are as follows: With increased barbell weight, the extension moment of the left knee joint was higher in the 80% condition than the 70% (p<.001). However, other variables were not statistically significant difference. According to the factor analysis of the variables related to maximum load attainment point of the ACL major injury variables, the first sub-factor was the internal shear force, the posterior shear force, the abduction moment, and the muscle activity of the VL. The second sub-factor was the extension moment of the knee joint, compressive force, adduction moment, and the third sub-factor was the muscle activity of BF. Conclusion: These results indicate that the possibility of ACL injury can be lowered when performing a stable snatch movement.

부동산금융규제의 법적 한계 고찰: LTV를 중심으로

문제헌 ( Moon Jeheon ) 한국금융법학회 2021 金融法硏究 Vol.18 No.1

금융분야는 대표적 규제산업으로 정부규제가 가장 많은 부문으로 꼽힌다. 주택시장 안정화 대책을 내놓을 때마다 등장하는 LTV 규제도 이에 해당한다. 규제는 피규제자의 자유와 재량권을 제약한다는 점에서 엄격한 법적 요건을 갖추어야 한다. LTV 규제는 원래 창구지도 형식으로 2002년 9월 운영되다가 법적 근거가 없다는 지적에 따라 2007년 7월에야 법제화된 역사를 갖고 있다. 금융위원회 고시 형식으로 각 금융회사의 감독규정에 LTV 규제조항을 신설한 것이다. 제정 형식은 상위법령인 법률과 대통령령에서 위임받아 규정하는 위임 명령의 방식을 채택했다. 따라서 LTV 규제는 위임명령으로서의 법적 요건인 구체성과 명확성을 갖추어야 한다. 즉 위임명령이 적법하려면 구체적이고 명확한 근거가 있어야 하고 포괄적 위임이 금지되며 모법에서 위임하지 않은 사항을 스스로 규정할 수 없다는 한계를 벗어나지 않아야 한다. 본 연구는 LTV 규제 법령이 위임명령의 요건에 부합하는지를 문헌 검토를 통해 분석해 보았다. 분석 결과 위임의 범위와 한계를 벗어나거나 상위법령에 위임근거 없는 것으로 나타났다. 이는 현행 LTV 규제법규 체계를 개선할 필요가 있음을 시사한다. The financial sector is a representative regulatory industry, and is counted as the sector with the most government regulation. This is also the case with the LTV regulation, which appears whenever measures are taken to stabilize the housing market. Regulations must have strict legal requirements in that they limit the freedom and discretion of the regulated person. The LTV regulation was originally operated in September 2002 in the form of a window map, but has been legislated only in July 2007 according to the point that there is no legal basis. In the form of a notice by the Financial Services Commission, the LTV regulatory provisions were newly established under the title of “Risk Management for Mortgage Loans” in the supervisory regulations of each financial company. The form of enactment adopted the law of establishing each financial company, which is a higher statute, and the method of delegation order stipulated by the Presidential Decree. Therefore, LTV regulation must have concreteness and clarity, which are legal requirements as a mandate. In other words, for a delegation order to be legal, it must have specific and clear grounds, comprehensive delegation is prohibited, and it must not deviate from the limit of being unable to self-define matters not delegated by the parent law. This study analyzed through literature review whether the LTV regulatory statute meets the requirements of the mandate. As a result of the analysis, it was found that there was no basis for delegation beyond the scope and limits of delegation or in higher statutes. This suggests that there is a need to improve the current LTV regulatory system.

달리기 시 인솔의 굽힘 강성 증가에 따른 발목과 중족골 관절의 운동학적 변인 및 관절 협응에 미치는 영향

( Sungmin Kim ),( Jeheon Moon ) 한국운동역학회 2021 한국운동역학회지 Vol.31 No.3

Objective: The aim of this study was to analyze body stability Joint coordination pattern though as bending stiffness of shoes during stance phase of running. Method: 47 male subjects (Age: 26.33 ± 2.11 years, Height: 177.32 ± 4.31 cm, Weight: 65.8 ± 3.87 kg) participated in this study. All subjects tested wearing the same type of running shoes by classifying bending stiffness (A shoes: 3.2~4.1 N, B shoes: 9.25~10.53 N, C shoes: 20.22~21.59 N). They ran 10 m at 3.3 m/s (SD ±3%) speed, and the speed was monitored by installing a speedometer at 3 m intervals between force plate, and the measured data were analyzed five times. During running, ankle joint, MTP joint, coupling angle, inclination angle (anterior-posterior, medial-lateral) was collected and analyzed. Vector coding methods were used to calculate vector angle of 2 joint couples during running: MTP-Ankle joint frontal plane. All analyses were performed with SPSS 21.0 and for repeated measured ANOVA and Post-hoc was Bonferroni. Results: Results indicated that there was an interaction between three shoes and phases for MTP (Metatarsalphalangeal) joint angle (p = .045), the phases in the three shoes showed difference with heel strike~ impact peak (p1) (p = .000), impact peak~active peak (p2) (p = .002), from active peak to half the distance to take-off until take-off (p4) (p = .032) except for active peak~from active peak to half the distance to take-off (p3) (p = .155). ML IA (medial-lateral inclination angle) for C shoes was increased than other shoes. The coupling angle of ankle angle and MTP joint showed that there was significantly difference of p2 (p = .005), p4 (p = .045), and the characteristics of C shoes were that single-joint pattern (ankle-phase, MTP-phase) was shown in each phase. Conclusion: In conclusion, by wearing high bending stiffness shoes, their body instability was increased during running.

Force Production Patterns of Muscles Surrounding Knee During Running and Cutting Maneuvers: A Musculoskeletal Modeling Approach

Jusung Lee,Kichung Lee,Jeheon Moon,Tejin Yoon 대한운동학회 2022 아시아 운동학 학술지 Vol.24 No.1

OBJECTIVES The purpose of this study was to investigate the force production patterns of individual muscles surrounding the knee during running (RUN) and cutting (CUT) tasks. METHODS Thirteen women (24.2±3.5 yrs, 162.8±6.0 cm, 55.3±6.2 kg) performed a series of running and cutting tasks. Running and cutting motions were recorded using a motion capture system and ground reaction force (GRF) was recorded using a force plate. Three-dimensional knee angle, ground reaction force, and knee joint moment were calculated using Visual3D software. OpenSim musculoskeletal modeling software was used to calculate the force of individual muscles including the medial hamstring, biceps femoris long head, biceps femoris short head, rectus femoris, vastus medialis, vastus lateralis, gastrocnemius medialis, and gastrocnemius lateralis. All data were analyzed for loading response (or weight acceptance), mid-stance, and final push-off periods, respectively and were compared between two tasks. RESULTS At loading response: external rotation angle, medial and vertical GRFs, and valgus moment for the CUT task were greater than those of the RUN task. Compared to the RUN task, the CUT task showed: 1) an increase in lateral hamstring muscle force at weight acceptance, 2) a decrease in hamstring muscle force and an increase in medial vastus muscle force at mid-stance, and 3) an increase in lateral gastrocnemius muscle force at final push-off. CONCLUSIONS Selective force production patterns of muscles surrounding the knee seem to offset the external load caused by the cutting motion. We anticipate that our results will provide basic data for future training programs designed to prevent noncontact knee injuries.

Development of fermented sprouted ginseng material fortified with functional ingredients using lactic acid bacteria and premium dog food manufacturing using the fermented sprouted ginseng material

Jisu Mun,Haeju Moon,Seungwoo Baek,Hyeonji Kim,Sehyen Byen,Jeheon Oh,Seongjin Park,Hyuna Park,Junhyeong Kim,Sugon Kim,Sukheung Oh 한국식품영양과학회 2022 한국식품영양과학회 학술대회발표집 Vol.2022 No.10