The effect of plyometric training applied to volleyball players on selected physical and physiological parameters

The aim of this study is to evaluate the effect of plyometric training applied to volleyball players for 8 weeks on isokinetic strength, anaerobic power, vertical jump, agility, speed and balance parameters. The research was conducted using a single-group pretest-posttest weak experimental design, which is one of the quantitative research approaches. The research group consisted of 10 female volleyball players competing in the Turkish Women's Volleyball League, with an average age (year) of 23.80±4.31 and an average height (cm) of 179.94±6.36. After the preliminary tests were taken, plyometric training was applied to the research group, 2 days a week for 8 weeks, in addition to their routine training, and post-test measurements were made. SPSS 24.0 program was used to evaluate the data obtained from the research. With the data showing normal distribution, paired t test (paired simples t) analysis was applied to determine the test results of the same sample group in the pre-test and post-test. As a result, when we look at the jumping performance parameters, it is seen that there are significant improvements in the squat jump, active jump, squat jump power, active jump power and active jump-squat jump difference power values between the pre-test and post-test values. Another parameter, speed, which is one of the motoric characteristics, was examined. When the results obtained at different distances such as 5 m, 10 m and 15 m are evaluated, it is not found to be statistically significant, but when the pre-test and post-test values are examined, it is 0.02 unit at 5 m speed, 0.04 unit at 10 m speed and 0.05 unit at 15 m speed. It was determined that there was unit development. Another feature examined in the research was agility. When the results of the applied training are evaluated, a statistically significant difference is seen. The reason for this significant development is that it is known that the sudden resistance production of the muscle is important in the cycle of acceleration, deceleration, sudden change of direction and acceleration in the agility feature, and the fact that plyometric exercises are performed at high intensity to increase strength plays a role. Regarding balance, which is another motoric feature, no significant difference was observed in the results of single-leg and double-leg measurements. The reason for this may be that plyometric exercises were not preferred in the form of movements that improve the balance feature in the applied training content. On the other hand, when looking at the change between pre-test and post-test data, it was observed that there were unit improvements in all parameters. Although it seems that the desired level of statistical significance has not been reached, it can be said that the applied studies have made positive contributions. Considering another parameter, anaerobic power performance, pedal speed on bicycle ergometry is 5 seconds. 10 sec. and 15 sec. In the power values revealed in the measurements, also anaerobic power 0-5 sec. There is also a significant difference in the results obtained in w/kg. Another parameter included in the study is isokinetic strength measurements. Here, it is determined that there is a significant difference at the values of 60° and 180° in the concentric contractions caused by the muscle tissue while the knee joint performs flexion and extension at different angles. It can be said that plyometric exercises are studies in which high resistance production occurs by releasing the energy stored in the muscle as a result of sudden contractions during a mechanical action by switching from the eccentric phase to the concentric phase at high intensity. Therefore, it can be recommended to be used as a preferred training method in order to develop sports performance characteristics where explosive force or power output is important. Looking at the results of the study, it supports the idea that the applied plyometric training program improves performance parameters. Keywords: Volleyball, Plyometric Training, Anaerobic capacity, Speed