Background and aims: proprioception and balance are two effective factors on improving performance and sport injury prevention, but the effect of participate in different sport activates on this sense has been studied less. So, the aim of this study was to compare the knee joint sense position in soccer player, volleyball player and non-athlete men.Methods: 45 subjects including 15 soccer players, 15 volleyball players, 15 non Participated in this study. The Knee joint position sense of the dominant leg of these subjects was assessed through 15, 30, 60 degrees flexion reconstruction with closed eyes and in closed movement chain using electrogoniameter. Data were analyzed using one way ANOVA test and TUKEY POST HOC test.Results: The results showed that the mean of absolute error in 60 degree reconstruction in volleyball players is significantly less than absolute error in soccer players and non-athletes (P<0.05). There was not significant differences between mean absolute error in 15, 30 degrees in the three groups of subjects (P>0.05).Conclusion: volleyball players have better knee joint position sense in 60 degree reconstruction.Maybe plyometric training specially jump- descend with body weight can help to improving knee joint position sense.

The main purpose of this study was to investigate the effect of short term creatine supplementation monohydrate supplementation with tensile training (exercise with cache) on aerobic and anaerobic power of volleyball players from 30 to 40 years of age. Fifty volleyball players from 30 to 40 years of age voluntarily participated as a sample in the study population after completing the health questionnaire. Subjects were randomly divided into 4 groups of elastic training and supplemented creatine monohydrate, elastic training, placebo and supplemented alone, and control and elastic training group. The protocol was completed for 8 weeks, 3 sessions a week. Supplementing creatine monohydrate was also 4 servings per day at 5 grams per serving. The measurement of aerobic power was carried out using a test run of 1 m (1609 m) and an anaerobic power with RAST test. To analyze the data, this study was conducted to compare intraperitoneal mean of T-test and to study the effect of eight weeks of training in four groups of covariance test. SPSS 21 software was used to analyze the data and the Excel 2010 software was employed for drawing charts. The results showed that eight weeks of elastic training accompanied with Creatine Monohydrate Supplements led to a significant improvement in aerobic power and anaerobic power of volleyball players (p ≤,0. 05). Considering the positive effect of supplementation of creatine supplementation and elastic exercise on aerobic and potency exercises also mentioned in other references, coaches, athletes and nutrition team members of sports teams are suggested to be cautious in the diet of athletes,in particular, since the side effects have not been reported for short-term use.

Background and Objectives: The aim of the present study was to investigate the effect of six weeks of volleyball training on lipid and lipoprotein profiles of elite high school male volleyball players in the Golestan Province (Iran) during preparation season for an international championship in France. Methods: Training group included 12 elite volleyball players in students’ premier league and control group included 12 healthy non-athlete male students. The training group practiced at 60-85% of maximum heart rate for six weeks, 90 minutes per session, six sessions per week and three sessions a day (first session: technical practice, second session: tactical practice and third session: technical/tactical practice). Blood samples were taken after 12 hours of fasting both before and after the training. Results: Level of total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C) and LDL-C/HDL-C increased in the training group (P> 0. 05). However, there was a significant difference between the two groups in TC and LDL-C levels (P<0. 05). Level of triglyceride, VLDL, and TC/HDL-C reduced in the training group after six weeks of training (P> 0. 05). Conclusion: Our results show that the six-week volleyball training during the preparation season can cause abnormalities in plasma lipid profile.

Background and Aim: The purpose of the present study was to investigate and compare the impact of taping and two types of braces (Lacy brace and Brace Neoprene) on functional performance of volleyball players with an unstable foot ankle. Materials and Methods: In the current comparative research, 15 volleyball players of Iraqi Kurdish State, who had an unstable foot ankle (average age: 21. 93± 1. 94 years, height: 1. 85± 0. 08m, weight: 80. 50± 7. 25kg, and Body Mass Index: 23. 37± 1. 65 kg/m² ) were included. Functional tests included Jump Sargent and Y Balance Test. Data was analyzed using repeated Analysis of Variance (repeated ANOVA) in SPSS, version 22 (p˂ 0. 05). Result: The findings showed that in Brace Neoprene (p˂ 0. 001) and Lacy brace (p˂ 0. 001), the scores of Y Balance Test and all three protecting devices, including taping (p ˂ 0. 001), brace neoprene (p ˂ 0. 002), and Lacy brace (p ˂ 0. 001), had a positive impact on the vertical jump test score, but these three types of protective equipments had no certain superiority over each other prior to and after the practices. Conclusion: Based on the findings of the present study and since in Y Balance Test the taping had no effect on the results of the test, overall, no difference was found between the three types of protective devices. Also, based on the findings of the previous studies, showing that using braces is less expensive, it seems reasonable to use the brace compared with taping. It is noteworthy to remind that the preference of one of these methods to other is dependent on the factors like the convenience of the athlete and the biomechanical items, which deserve further investigation.

Background: volleyball is a sport with technical elements and explosive power. Objectives: This study investigates the relationship between sprint speed and isokinetic knee strength applied at different angular velocities in male volleyball players. Methods: This study was conducted on 15 volunteer male volleyball players (age,17-25 years, height,1. 75 + 0. 12 m). Isomedx 2002 isokinetic dynamometer is employed to measure the isokinetic strength, and a 20msprint test is conducted to measure the speed. In measuring knee flexion and isokinetic extension strength, quadriceps and hamstring concentric/eccocentric are measured separately on both legs at 60°, /sec angular velocity for three repetitions, at 180°, /sec for six repetitions, and at 300°, /sec for nine repetitions. For statistical analysis, the Spearman’, s correlation test was performed using SPSS 18. 0 (SPSS Inc., USA) software. Results: The highest torque value in subjects was recorded on both sides at 60°, /sec angular velocity, 180 and 300 degrees, respectively, were lower. There was no significant relationship between speed and isokinetic strength at different angular velocities. Conclusions: Based on our results, the highest peak torque in volleyball players was found to be at 60°, /sec angular velocity while no significant correlation was found between isokinetic strength of the knee at different angular velocities and speed of volleyball players.

In this study, the prevalence, type and the probable causes of sport injuries in Iranian super league man volleyball players was evaluated. The study was descriptive research and the statistical population was about 160 volleyball players that were present in Iran's super league in the year 2005. The statistical sample was about 60 mans with at least 3 years experience in volleyball. The information was gathered using a combined questionnaire by interviewing the volleyball players and their coaches. During the training and competition seasons, lower limbs with 44% and 46/8 % were the most vulnerable organs to injuries. During training, joint injuries with 46/1 % and during match, muscular injuries with 43/5 % were the most common kind of injuries. During training and match, sprain with 46/8 % and 38/6% was the most common joint injury and spasm with 42% and 37/3 % was the most common muscular injury. During training, fracture with 49/4% and during match, the close fracture with 54/6% was the most common bone injuries. During training and match, fingers with 42/8 % and 44/9 % were the most vulnerable organs of upper limbs, ankle with 33/1% and 38/3 % the most vulnerable organs of lower limb and lumbar with 68/6% and 75% the most vulnerable organs of trunk, head and neck to be injured. During training and match, Sprain with 23% and 20% was the most common kind of injury as a whole. During training, fingers with 15/58% and during match ankle with 17/4% were the most vulnerable organs of all body to get injuries. And each considered probable factors with different effects had caused injuries. The study revealed that body building in volleyball, ground/surface condition and quality of personal equipment could be important factors to associate with the injuries in this sport. Eventually, it was concluded that fingers, lumbar and ankle are the most vulnerable organs and injuries which are mostly the result of over Research on Sport Science. No 14, 2006 15 using organs with incorrect techniques. Therefore, correcting the techniques might play a considerable role in prevention of injuries.

Presence of supportive atmosphere in the form of organizational variables and coach-athletic relationships, while making an optimal executive commitment, had significant effect on athlete's turnover. Therefore, the main purpose of research was designing model of volleyball player’ s turnover intention based on coach behavioral support, club’ s support and organizational commitment. Sample size consist of N= 90 volleyball players and coaches, that selected with snowball and cognitive sampling method. To collect data, Kim (2007) turnover intention questionnaire, modified version of Eisenberger (1996) perceived organizational support and perceived supervisor support and Meyers (1993) organizational commitment questionnaire used. The results showed that all three variables, perceived organizational support (β =0. 86), perceived supervisor Support (β =0. 88) and organizational commitment (β =0. 78) had significant effect on turnover intention. Also, the results of the regression test indicated that organizational factors (β =0. 86) were the main predictor of volleyball player's turnover. So, with consider to destructive outcomes of the turnover in elite athletes, necessity for attention in applying supportive styles by coach and top managers of the organization, for retain of volleyball players are recommended.