• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.27-33
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• 2014

In volleyball, the most common injuries are anterior cruciate ligament (ACL) tears. For this reason, volleyball players frequently use knee brace as prophylactic and rehabilitation measures. The purpose of the study was to investigate the effects of knee brace on anterior cruciate ligament injuries risk factors during spike take off in female volleyball players. Fifteen female volleyball players were recruited and performed randomly spike take off with and without knee brace. Kinematics and ground reaction data were collected to estimate the anterior cruciate ligament injuries risk factors. The ACL risk factors are knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle, shank maximum external rotation angle, knee maximum extension moment and knee maximum abduction moment. Data were analyzed with paired samples t-test with Bonfferoni collection. Female volleyball players with knee brace had no significant results in knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle and shank maximum external rotation angle compare to without knee brace. Female volleyball players, however, with knee brace showed more reduced knee maximum extension moment and knee maximal abduction moment than without knee brace. In conclusion, Female volleyball players with knee brace reduced anterior cruciate ligament stress.

• Journal of Convergence for Information Technology
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• v.9 no.7
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• pp.153-158
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• 2019

The purpose of this study was to compare the isokinetic muscular strength of the knee joint between female volleyball and table tennis players. A total of 27 elite volleyball players and 27 table tennis players participated in the study. This study measured both knee extensor and flexor strengths of volleyball and table tennis players using the isokinetic dynamic test. Peak torque was measured by performing maximal voluntary flexion and extension three times at $60^{\circ}/s$. Volleyball players had higher knee extensor and flexor strengths than table tennis players. No significant difference in both knee strengths was noted in table tennis players. However, volleyball players showed significant differences in both knee strengths. Height and weight showed a positive correlation with knee strength. This study found that volleyball players had greater knee strength than that of table tennis players. We also found that volleyball players have asymmetrical knee strength. Comparison with other sport players is warranted to better understand isokinetic muscular strength of the knee joint.

• Journal of International Academy of Physical Therapy Research
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• v.8 no.2
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• pp.1158-1162
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• 2017

The purpose of the study was to investigate the strength of sokinetic muscle by the position of a volleyball players. Analysis and comparison of shoulder dynamic stability will be conducted according to rotational movement of the shoulder during spiking and serving amongst the various positions. Fifty professional Korean female volleyball players (age: 20~30), all different positions - attacker (left and right), center, setter, and libero were The concentric peak torque, strength ration of the internal and external rotation of the shoulder girdle for both dominant and non-dominant arms. Firstly, there were significant differences found for the strength ratio between the setter and the other positions in the dominant arm. On a second note, there was a significant decrease in shoulder dynamic stabilization for both the attacker and center in the dominant arm. However, there were no significant differences for the setter or the libero. This study suggests that the isokinetic muscle strengths of the volleyball players are different from each other.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.438-447
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• 2012

This study was to explore the social network structure of professional volleyball players and analyze network variables and resource exchange. This study selected 127 players of Korean professional volleyball in ten team of male and female using the purposive sampling method. The research method utilized general social survey of NGQ(Name Generator Question) and interview. To analyze data, NetMiner 3.0 and SNA(social network analysis) were used. The conclusion based on above study method and the result of material analysis are here below. First, social network of professional volleyball players is scale-free network following power law. Centrality and herb of club members' network show up richer-get-richer and poor-get-poor by collecting links of back of beyond. Second, social network structure of professional volleyball players influence resource exchange.

• Journal of International Academy of Physical Therapy Research
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• v.2 no.1
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• pp.229-236
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• 2011

The purpose of this study was to comparatively analyze the active stability of shoulder joints according to the frequency of overhead motions, such as serving and spiking, engaged in by female professional volleyball athletes who play different positions, and to provide the results as the basic data for developing exercise programs to prevent shoulder joint injuries. The subjects of this study were 50 Korean female professional volleyball players and positions were as follows: left and right attackers, centers, setters, and liberos. The external rotation and internal rotation muscle strength and muscle strength ratios of the dominant and non-dominant arms of all subjects were measured using Biodex. The results of this study are as follows: Frist, no significant differences were found in the internal and external rotation muscle strength of the dominant and non-dominant arms between positions. Second, for the shoulder joint muscle strength ratio of the dominant arm, by position, the setter showed significantly greater stability compared to the other positions. Third, for the shoulder joint muscle strength ratio of the non-dominant arm, by position, no significant difference in stability between positions was found. Fourth, it was found that the dominant arm had significantly greater instability of the shoulder joint than the non-dominant arm for attackers and centers, but no significant difference was found for setters and liberos. This study comparatively analyzed the muscle strength ratios of the external/internal rotations and dominant/non-dominant arms, which can determine the stability of the shoulder joints between female professional volleyball playing positions that engage in jumps and spikes using only the dominant hand and positions that do not.

• Nutritional Sciences
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• v.8 no.2
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• pp.118-124
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• 2005

To examine the eating attitudes, weight concerns, dietary intake, and menstrual function of Korean female elite athletes, 109 subjects in seven sports disciplines (rhythmic gymnastics, synchronized swimming, badminton, volleyball, Taekwondo, field hockey, and soccer) responded to a questionnaire consisted of three parts; eating attitudes and behavior(Eating Attitude Test-26; EAT26), body weight perception (Body Dissatisfaction Index: BDI) and weight control behavior, and menstrual history and status. They also recorded three-day dietary intake. Body weight (43.6$\pm$4.3 kg) and body mass index (16.7$\pm$1.4 kg/$m^2$) in rhythmic gymnasts were lower than those in other athletes (P<0.05). EAT26 scores were not different among sport events (12.3$\pm$6.5 total), however, eating disturbances (EAT26 score$\geq$20) were highly prevalent in aesthetic athletes ($30\%$) than in others ($5\%$). More than half of the athletes perceived themselves overweight and four fifth of the athletes desired to reduce weight about 4.4 kg. The gymnasts consumed the lowest caloric intake (1028:t371) while the volleyball players did the highest (2995$\pm$342 kcal/d) (P<0.05). The BDI score was not different among sport events. Three fourth of the athletes experienced weight control, and the most frequently used weight reduction method was exercise followed by using robber suits, diet, and sauna. About $40\%$ of the subjects reported irregular menstrual cycles, but menstrual dysfunction ($\leq$6 menses/yr) was only $5\%$. Generally, the Korean female elite athletes desired to reduce weight from their current body weight. No differences in eating attitude and body dissatisfaction were noticed among athletic disciplines. However, eating disturbances were highly prevalent in aesthetic athletes who also reported much less energy intake than the recommend daily energy intake. It appeared that weight reduction methods were not properly practiced in these population. Menstrual dysfunction was minimally reported.