• 대한물리의학회지
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• 제4권1호
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• pp.49-56
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• 2009

Purpose : The Purpose of this study was to investigate the effects of image training and vibration on performance of vertical jumping. Methods : Subjects was classified into two groups, which were image training group(n=20) and vibration application group(n=20). The standard methods of each intervention were image training with listening recorded indication for 5 minute and vibration with speed of $1200{\pm}200\;rpm$. Muscle strength was measured using vertical jump performance. Results : The vertical jump performance was significantly increased after image training and vibration application(p<.05), however, it was more significantly after image training(p<.05). Conclusion : This study showed that image training and vibration application were effective treatment strategy on increase of muscle strength. Therefore, it could be considered as a treatment method in the patients with musculoskeletal disease including fracture, chronic degenerative disease and disuse atrophy.

• 한국운동역학회지
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• 제13권3호
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• pp.27-46
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• 2003

The purposes of this study were to determine the functions of actions of the limbs during each of the three support phases of the triple jump and their relationships with the performance of the triple jump. Four elite male triple jumpers were participated as subjects. The statistical analyses used were the Pearson product moment correlation coefficient for establishing relationships and simple regression analyses to determine and compare the relationships between the change of the horizontal velocity and the change of the vertical velocity during different support phases. A level of significance at p<.05 was set. The actions of the arms were responsible for about 25%, 25%, and 30% of the decrease in the horizontal velocity of the whole body center of gravity during the support phases of the hop, step, and jump, respectively. The change in the velocities of the whole body center of gravity due to the actions of the free limbs were significantly related with the whole body center of gravity during each support phase. The action of the support leg was associated with the decrease in the horizontal velocity and the increase in the vertical velocity of the whole body center of gravity during each support phase.

• 한국운동역학회지
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• 제27권1호
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• pp.25-33
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• 2017

Objective: The purpose of this research was to establish the differences of ground reaction force variables and sensations according to the foot types and the structures of the inner arch support band during $2^{nd}$ vertical ballet jump. Method: 12 Female ballet majors in their twenties who have danced for more than 10 years and had no injuries were selected for this research. Independent variables consist of the foot type (pes rectus, pes planus) and the structure of the inner arch support band (no band, x-shaped, linear shaped). Dependent variables consist of ground reaction force variables and relative wearing sensation. Results: The impact decreased the most when x-shaped bands were used on pes rectus and rigid pes planus. When linear-shaped bands were used on flexible pes planus, the impact decreased. Conclusion: The bands also helped reduce the impact on pes rectus. Furthermore, it is clear that according to the foot type, the impact reducing band structures perform differently. The inner arch support bands were necessary for jump training for any foot type.

• 한국운동역학회지
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• 제19권3호
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• pp.489-497
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• 2009

본 연구의 목적은 최대 수직점프시 개인내에서 발생하는 수행력의 차이와 이와 관련된 역학적 변인들의 영향을 규명하는데 있다. 이를 위해 20대 남성 20명을 대상으로 6회의 최대 수직점프를 실시하였으며, 이 가운데 최고 수행과 최저 수행을 추출한 후 수행력과 역학적 변인들을 비교, 분석하였다. 분석 결과, 우수수행과 비우수수행사이의 점프 높이는 약 4cm로 10% 정도의 유의한 차이를 보였으며 이는 이지시 중심의 높이(25%)와 이지속도(75%)에 기인하였다. 무릎관절과 엉덩관절의 역학적 출력은 유의한 차이가 나타나지 않은 반면 발목관절에서는 최대신전모멘트, 최대파워, 일량이 우수수행에서 유의하게 높았다. 최대수직점프에서 개인내 수행차는 주로 발목관절의 운동에 주로 기인한다고 할 수 있으며, 무릎과 엉덩관절의 역학적 출력은 수행력에 주요한 기여를 하지만 개인내 변이가 크지 않아 개인내 수행차에는 영향을 미치지 못하였다. 이에 비추어 점프력을 극대화하기 위해서는 트레이닝의 과정에서 발목관절의 역학적 출력을 증가시킬 수 있는 방안에도 보다 관심을 두어야 할 것으로 사료된다.

• 한국운동역학회지
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• 제27권2호
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• pp.141-147
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• 2017

Objective: We obtained force-displacement curves for countermovement jumps of multiple heights and examined the effect of an arm swing on changes in vertical jumping strategy. Countermovement jumps with hands on hips (Condition 1) and with an arm swing (Condition 2) were evaluated to investigate the mechanical effect of the arm movement on standing vertical jumps. We hypothesized that the ground reaction force (GRF) and/or center of mass (CoM) motion resulting from the countermovement action would significantly change depending on the use of an arm swing. Method: Eight healthy young subjects jumped straight up to five different levels ranging from approximately 10% (~25 cm) to 35% (~55 cm) of their body heights. Each subject performed five sets of jumps to five randomly ordered vertical elevations in each condition. For comparison of the two jumping strategies, the characteristics of the boundary point on the force-displacement curve, corresponding to the vertical GRF and the CoM displacement at the end of the countermovement action, were investigated to understand the role of arm movement. Results: Based on the comparison between the two conditions (with and without an arm swing), the subjects were grouped into type A and type B depending on the change observed in the boundary point across the five different jump heights. For both types (type A and type B) of vertical jumps, the initial vertical force at the start of push-off significantly changed when the subjects employed arm movement. Conclusion: The findings may imply that the jumping strategy does change with the inclusion of an arm swing, predominantly to modulate the vertical force advantage (i.e., the difference between the vertical force at the start of push-off and the body weight).

• 한국운동역학회지
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• 제33권3호
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• pp.85-93
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• 2023

Objective: This study examined differences in joint kinematics and movement variability of lower extremity between adolescent athletes with and without lateral ankle sprain (LAS) history during drop vertical jump. Method: Fourteen adolescent athletes with LAS history and 14 controls participated in this study. The independent variable was group while dependent variables were 3D joint kinematics and movement variability of hip, knee, and ankle joint. Ensemble curve analyses were conducted to identify differences in movement strategies between two groups. Results: The LAS group showed that greater eversion during jump phase compared with the control group. Additionally, less movement variability was found in the LAS group during the pre-landing and jump phases in ankle and hip joints compared with the control group. Conclusion: The LAS group may adapt the environmental constraints by reducing the movement variability in ankle and hip joints. However, training programs focusing on recovery of ankle function should be emphasized after LAS because excessive pronation for prevention of LAS during the jump phase may result in reduced performance.

• 한국운동역학회지
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• 제21권5호
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• pp.611-619
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• 2011

The purpose of this study was to analyze the kinematics of the men's triple jump at the 2011 Daegu World Championships by comparing the results to those at the 2009 Berlin World Championships. The kinematic data were gathered from two steps before take off to the landing using a seven panorama system, and these data were divided into 3 phases for 8 participants. The average jump for the finalists was longer in the Daegu championships (17.46 m) than in the Berlin championships (17.28 m). The longest jump record was increased by 23 cm. The step was the longest at 36% of the total distance, followed by the hop at 30% and the jump at 34%. The first and third phases were substantially longer than the second phase (the step). The horizontal speed at take-off increased in the order hop, step, and jump. Overall, in comparison with the results from Berlin, the horizontal velocity increased, the vertical velocity decreased, and the landing angle decreased.

• 대한물리치료과학회지
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• 제29권1호
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• pp.47-54
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• 2022

Background: Plyometric exercise is an exercise exerting forceful power in a brief period using isotonic activation. It is effective to improve reaction of muscle, agility, endurance and athletics performance. Weight training is an exericse improving muscular strength, endurance and respirating ability applying diversely in frequency and load of exercise Plyometric exercise and Weight training is to facilitate the athletics performance though improving the function of lower limb muscle, there is a difference that Plyometic jump squats is the way to improve agility and Weight training is the way to improve muscular strength. Therefore, it is necessary to know how this difference effects on athletics performance as measuring ankle, ROM, and jumping ability. Design: Randomized controlled trial. Method: This study was conducted with the voluntary participation of 40 university students, who were randomly assigned to jump squat and calf raise groups (n=20 per group). For each subject, we measured the range of motion of the ankle joint before and after exercise, as well as a standing broad jump and vertical jump test performance. We compared the performance indices before and after exercises using paired t-tests, and between groups using independent-samples t-tests. Conclusions: Both jump squat and calf raise exercises improved ankle joint dorsiflexion and plantar flexion, as well as standing broad jump and vertical jump height performance. However, there were no significant differences before versus after exercise, or between exercise types. Although jump squats and calf raises have different purposes, it is thought that, in combination, these exercises improve performance more effectively than either alone, and that such a combined exercise program improves the quality of training in both the general public and athletes in various sports.

• 한국운동역학회지
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• 제21권5호
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• pp.621-629
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• 2011

The purpose of this study was to analyze the kinematics of the women's triple jump event at the 2011 Daegu World a Chmpionships by comparing them to those of the 2009 Berlin World Championships. The kinematic data were gathered from two steps before take off to the landing using a 7-camera panorama system. The data were then divided into 3 phases for each of the 8 participants. Similar average results were found the final contestants in the Daegu and Berlin championships, 14.58 m and 14.51 m, respectively. The first step had a relatively short length percentage (29%) compared to the hop and jump (36% and 35%, respectively). At the take off, the horizontal velocity was the lowest for the step, followed by the hop and jump. These results were different from the results for the men, who had an order of hop, step, and jump. Overall, in a comparison of the Daegu and Berlin participants, the vertical speed at take off for the three events was reduced compared to the horizontal speed.

• 대한물리의학회지
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• 제3권1호
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• pp.1-9
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• 2008

Purpose : The purpose of this study is to assess the effects of ice immersion to the ankle, foot on vertical jump, isokinetic exercise. Methods : Thirty volunteers from universal students who had not sustained an injury to the lower extremity within the past 6 months were randomly assigned to either an experimental or control group. Subjects in the experimental group performed vertical jump and isokinetic exercise before and after the application of a 15-minute ice immersion($50-55^{\circ}F$) to the ankle and foot. Subjects in the control group performed vertical jump and isokinetic exercise before and after the application of a 15-minute resting. Results : Shuttle run was not significantly decreased after than before the application of a 15-minute ice immersion($50-55^{\circ}F$) to the ankle and foot(p<0.05). Vertical jump was significantly decreased after than before the application of a 15-minute ice immersion($50-55^{\circ}F$) to the ankle and foot(p<0.05). Speed $60^{\circ}$ of peak torque was significantly decreased after than before the application of a 15-minute ice immersion($50-55^{\circ}F$) to the ankle and foot(p<0.05). Speed $120^{\circ}$ of peak torque was significantly decreased after than before the application of a 15-minute ice immersion($50-55^{\circ}F$) to the ankle and foot(p<0.05). Conclusion : we think because the ice immersion decrease active, physical therapist should carefully consider the consequence of cold therapy to increase active.