• 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.

• Structural Engineering and Mechanics
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• v.83 no.5
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• pp.681-692
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• 2022

The vibrational response of the two bones in a Volleyball player's arm under ball impact is conducted. The two bones in hand, Ulna and Radius, are modeled as two cylindrical shells. The formulations associated with the shells' vibration are obtained using the energy method. Then, the results are extracted with the aid of the two-dimensional form of DQM in conjunction with Runge-Kutta. The results are validated by means of a published paper. Lastly, the role of parameters in determining vibrational frequency as well as deflection is explored through parametric studies. It was shown that the impactor speed and the time of the impact could be essential factors in determining the vibration behavior of the bones. This work can be used in the further investigation of the behavior of bones and physiological structures.

• Archives of Plastic Surgery
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• v.49 no.3
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• pp.440-443
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• 2022

Spinal accessory nerve (SAN) palsy is typically a result of posterior triangle surgery and can present with partial or complete paralysis of the trapezius muscle and severe shoulder dysfunction. We share an atypical case of a patient who presented with SAN palsy following an injury sustained playing competitive volleyball. A 19-year-old right hand dominant competitive volleyball player presented with right shoulder weakness, dyskinesia, and pain. She injured the right shoulder during a volleyball game 2 years prior when diving routinely for a ball. On physical examination she had weakness of shoulder shrug and a pronounced shift of the scapula when abducting or forward flexing her shoulder greater than 90 degrees. Manual stabilization of the scapula eliminated this shift, so we performed scapulopexy to stabilize the inferior angle of the scapula. At 6 months postoperative, she had full active range of motion of the shoulder. SAN palsy can occur following what would seem to be a routine volleyball maneuver. This could be due to a combination of muscle hypertrophy from intensive volleyball training and stretch sustained while diving for a ball. Despite delayed presentation and complete atrophy of the trapezius, a satisfactory outcome was achieved with scapulopexy.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.241-252
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• 2003

The purpose of this study was to evaluate performance characteristics in the success of team attack during volleyball game. Three dimensional analysis was performed with games of business teams. Analyzed variables were followed by the movement distance of a setter when A-quick was occurred, the position during the spike, the possibility area during the attack, the right and left distance of the assistance attacker, the distance between attacker and blocker, and the distance between blockers each others. 1. It is recommended that the movement distance of the setter be decreased in order to make stable set condition. 2. In order to make one person blocking, the formation was to be consisted of the right and left formation which was associated with the progressive attack performance of the assistance attacker. 3. It is useful to widen attack area. Also it is necessary to improve the enhancement of passing the ball against the blocking of an opponent player. Finally, it is necessary to develop kinematic variables to evaluate performance characteristics of players. Further study may consider the best defense position against the attack of the opponent player.

• Korean Journal of Community Nutrition
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• v.4 no.2
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• pp.231-238
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• 1999

This study was done to investigate the 12 college volleyball player's food behavior, nutrient intakes, and their serum lipid levels during the periods of training and detraining and to provide basic data for an effective program for the volleyball players during the period of detraining after the game season. The results were summarized as follows : The total daily energy intake of the players was $3,363{\pm}339kcal and 3,692{\pm}499kcal$ during the periods of the training and detraining, respectively. During the training period, daily intakes of protein, calcium and vitamin A, and $B_2$ were lower than the recommended dietary allowance for the players. During the detraining period, the players' daily intakes of calcium, iron, and vitamin A were even lower. However, the consumption of alcohol was dramatically increased during the period of detraining. The levels of serum triglyceride and very low density lipoprotein were significantly increased during the detraining period. Basal metabolic rates were significantly increased after the training period and diastolic pressure was decreased during the detraining period. In conclusion, out results suggest that the detraining of volleyball players for 10 days after intensive training, negatively affects their food behavior and serum lipid concentrations. Therefore, for the improvement of performance for the next game season, a planned program for the players' detraining period should be developed.

• Korean Journal of Applied Biomechanics
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• v.17 no.4
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• pp.57-64
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• 2007

The purpose of this study was to investigate comparative analysis of the vertical ground reaction force variables during landing from vertical jump blocking in volleyball through GRF analysis system. The subjects participated in this study were 6 male university volleyball player and 6 male acted as a control group. The results are as follows: 1. The skilled group was longer than the unskilled group in flight time during vertical jump blocking. 2. The skilled group was faster than the unskilled group in tFz2 during landing from vertical jump blocking. 3. The skilled group was higher than the unskilled group in Fz2 during landing from vertical jump blocking. 4. The skilled group was higher than the unskilled group in Fz2LR during landing from vertical jump blocking. 5. The skilled group was higher than the unskilled group in impulse during landing from vertical jump blocking. Consequently, during landing from vertical jump, the landing strategy of the skilled group was found as a form of a stiff landing. Therefore, this landing strategy will be required to strengthen of hip and knee extensors and ankle plantar flexors for injury prevention.

• 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.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.1-18
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• 2005

The purpose of this study was to evaluate performance characteristics. in the success of team attack during volleyball competition. For this, real game was analyzed using S-VHS video camera for three dimensional cinematography. The contents of this research were receive to set time, set to spike time, setter moving distance, ball position during set and attacker's relative ball position during jump and spike, and open area at spike. Among the various kinematical factors considered in this study, the ball height relative spiker and open area were found to be related to offensive performance. This finding implies that although their direct impact were not significant the other factors could have indirect impact on offensive performance by increasing open area. Thus, receiver, setter, assistant attacker, and main attacker should practice for successful performance in each stage. Lastly, it is necessary to develop kinematic variables to evaluate performance characteristics of players. Further study may consider the best defense position against the attack of the opponent player.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1413-1421
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• 2016

In this paper graphical exploratory data analyses are proposed for ball games in sports. The plot of sequence of scoring points of each team can be used to see how the playing game has been processed until the end of each set or quarter. With the plot of sequential score differences through all the games we can see a dominance of each team and the times of score changes, i.e., turnovers. The ternary plots show the contours of scoring compositions for each player and enable us to compare the scoring patterns of each team if any. Using the score sequence plot we also can see the score pattern distribution of players. For demonstration we use the results of the gold medal match between Russia and Brazil for men's volleyball and between USA and Spain for men's basketball at the London 2012 Summer Olympics.

• Clinics in Shoulder and Elbow
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• v.9 no.1
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• pp.119-123
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• 2006

Isolated avulsion of the lesser tuberosity of the humerus in adolescent is rare injury. The mechanism of injury is acute forced external rotation and with the arm in abduction which has been reported in children participating in sports such as football, hockey, volleyball, wrestling and skateboarding. The diagnosis is often delayed despite chronic pain and disability. Authors report the unique case of a skeletally immature adolescent Judo player who had an isolated avulsion of the lesser tuberosity of the humerus with the references.