Научная статья на тему 'Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players'

Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players Текст научной статьи по специальности «Науки о здоровье»

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Ключевые слова
countermovement & squat jump / elastic energy / drop 40cm jump

Аннотация научной статьи по наукам о здоровье, автор научной работы — Lleshi Enkeleida

The aim of this study is to define the effect of a Plyometric Training (PT) to volleyball players female in Albania and to evaluate the vertical jump height during the test Squat Jump (SJ), Countermovement Jump (CMJ), Drop Jump (DJ).The data were taken prior to Pre and Post afterwards PT. We give positive energy producing utilization of elastic energy to the female in volleyball. The data base is based on: before and after 12 weeks of exercise rebounds and is analyzed by ANOVA. Subjects are 2 female volleyball teams (N = 20). There is a Control (CO) panel and Experimental (EX)tests performed on three different SJ, CMJ, DJ 40cm in (Ergo jump test) and Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players 89 platforms Leonardo® Ground Force Reagimit Plate (GRFP)which express Fmax (kN), Pmax (w/kg), Time Contact (TCs), Air Time (TAs), TA/TCs.For each one person is measured Body Height (BH), Body Weight (BW), Body Mass (BMI). The 12‑week program was implemented by the EX group 2 times a week and resulted in a significant increase in vertical jump in the force value and maximum power of group CO. This study proved that plyometric exercises improve physical qualities especially muscular force and consequently the vertical jumper skills. It also serves on their integration as a part of a whole program for volleyball players.

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Текст научной работы на тему «Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players»

Section 11. Physical Education

• Circular complex nonstop training with 1015 planned exercises: squat jump with knees near the chest, the rotation 360 degrees, arm pumps, belly muscles, somersault etc.

Seventh day

• Break

Conclusion:

I am convinced that within a limited space it is difficult to deal strictly with such an important problem as the complex training methodology. However, something modest has been achieved. The research showed some quantitative and qualitative methodology on rating training complex as a viable and

profitable activity, which accelerated the achievements of training indicators and the results of team sports champion boxers SK “Tirana”. It pointed out some ideas, original concepts and practices that need to be carefully analyzed and evaluated by specialists of boxing. The idea of dividing training periods in several training stages, the idea of dismounting and converting preparatory types according to their relevant training tasks, the assessment of loadings according to the load coefficient and their distribution according to the respective scales, relative settings of the regeneration period, all these matters increase the profitability of training and its creative features.

References:

1. Dick F., 1984. Training Theory.

2. Dibra F., 2007. Athletics: Training Grounds Sports (Albanian).

3. Volkov. E.A., 1972: Sport recovery process (Translated into French by Russian, FIS).

4. Ibrahimi E., 2010 Box (Albanian).

5. Jorgoni A., 2005: Theory and Methodology of Sports Training. (Albanian).

6. Kiseliov V.A., Cerenicinov V.N., 2013: The Bases of Physical Preparation (Russian).

7. Matvejev L., 1981. Fundamentals of Sports Training.

8. Reka R., 2006: Box (Albanian).

9. Saltin B., 1973. Fundamentals in Metabolic Exercise.

10. Skender D.H., 2012: Physical Preparation in Sports. (Albanian).

11. Tschene P., 1977: Some new aspects of periodization of the high level training (translated into French from German, RFA. P. 379-382).

12. Verkhoshanski Y. 1977: Bases of training (Translated into French from Russian).

13. Weineck J., 1982 from Optimal Training.

14. Zaciorsky V., 1995: Science and Practice of Training, HK.

Lleshi Enkeleida, Sports University of Tirana PhD student at Sport Sciences Research Institute Sports University of Tirana Email: [email protected]

Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players

Abstract: The aim of this study is to define the effect of a Plyometric Training (PT) to volleyball players female in Albania and to evaluate the vertical jump height during the test Squat Jump (SJ), Countermovement Jump (CMJ), Drop Jump (Dj).The data were taken prior to Pre and Post afterwards PT. We give positive energy producing utilization of elastic energy to the female in volleyball. The data base is based on: before and after 12 weeks of exercise rebounds and is analyzed by ANOVA. Subjects are 2 female volleyball teams (N = 20). There is a Control (CO) panel and Experimental (EX)tests performed on three different SJ, CMJ, DJ 40cm in (Ergo jump test) and

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Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players

platforms Leonardo® Ground Force Reagimit Plate (GRFP)which express Fmax (kN), Pmax (w/kg), Time Contact (TCs), Air Time (TAs), TA/TCs.For each one person is measured Body Height (Bh), Body Weight (BW), Body Mass (BMI). The 12-week program was implemented by the EX group 2 times a week and resulted in a significant increase in vertical jump in the force value and maximum power of group CO. This study proved that plyometric exercises improve physical qualities especially muscular force and consequently the vertical jumper skills. It also serves on their integration as a part of a whole program for volleyball players.

Keywords: elastic energy, drop 40cm jump, countermovement & squat jump.

Introduction

The Volleyball game is characterized by the activity of jump performance. Considering the importance of this activity for the performance score and the frequency in which they occurs during game types of dance SJ, CMJ and DJ are an important indicator in volleyball game. Those jump styles we have implemented in a training program to volleyball player female in Albania over 12 weekly sessions with 2 seasons at week. Usages of plyometric exercises of DJ type during training in the sport of volleyball have shown an increase performance during the concentric phase of the muscle contraction. Observed during the concentric phase, this improvement is known to discharge the elastic energy stored in the sequence of elastic elements muscle during eccentric contraction, the length of the extension [1, 135-140]Komi & Bosco in their study have compared the performance of vertical leap in males and females in these three cases, SJ, CMJ and DJ, where men’s had a better performance than women, but women had a good use of elastic energy stored [2, 261-265]. One earlier study from Sheppard. Et. Al has reported that exist an average connection between force/power measurement in jump SJ and CMJ performance in elite volleyball team [3, 2096-2101]. A lot of researchers found that dance in height can be greatly improved bouncing between plyometric [1; 2 135-140,261-

265] [4, 583-588] compared a group exercise DJ, a group exercise isokinetic, and a controller group. They found that both DJ and isokinetic group jumped above obviously than the control group. A group of scholars [5, 5-10] have compared training with training CMJ DJ in training with weights. They found no significant differences between the DJ and CMJ group; both groups improved their ability in vertical jump by 8.4 cm after 4 weeks Trainings. This study proved that plyometric exercise support to volleyball female players as part of a 12-week program for improving the skills serve vertical jumper and performances of force and strength of the lower extremities.

Subject:

Participate two female volleyball teams with 10 athletes, whose physical characteristics are presented in table 1.The teams participating in this study are Tirana Volley which underwent our experimentation as the Experimental group and team Dinamo Volley was considered as the Control group. All of them were part of the Championship volleyball. Were given clear explanations to all participants on the study, including the benefits and risks of participation and if after these explanations, they refused to participate in the study, did not affect their decision in selecting their team’s matches. All participants gave their written consent to participate in the testing and data collection.

Table 1. - Average data volleyball players

Nr GROUPS Age Bady Hight (BH)cm BadyWeight (BW)kg BMI Kg/m%

10 EXS PERIMENT 17 173.7cm 62.06kg 20.64%

SD 1.6 4.9 6.5 2.08

10 CONTROLL 18 170.3cm 62.5kg 20.96%

SD 0.8 3.8 2.6 2.01

Procedures and Methods: ments of anthropometric measurements and then to

The volleyball players female test was done the tests in vertical jump performance of the three

24 hours after a total rest. We start with the assess- tests protocol [6,7, 60-78,80-85] and DJ SJ. CMJ

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Section 11. Physical Education

and was elected to a height of 40 cm. All the participants were informed about the tests on which will start the test also was decides to repeat the specific tests. Then they performed in maximum vertical jumps with hands in bowl with an odd rule to all of these disciplines: CMJ, DJ and SJ. The e SJ and CMJ tests were developed in Ergo test Technology. Ergo jump in order to define the use of elastic energy but also we Platform Leonardo (GRFP) for deter-

mining the force and power extremities.Tests have been developed in laboratory environments Sports of University of Tirana.

Result

The table below present’s data anthropometric measurements taken both groups in the study but data test SJ and CMJ obtained from the test protocol (Cometti, G., Cometti. D.,2009. Marell, M., Risalti, M.,2007) in Ergo test Technology Ergo jump.

Table 1. The general table of the SJ&CMJ tests in (Ergo test Technology Ergo jump)

Nr Teams Age Body Height BH cm Body Weight BW kg BMI Kg/m Jump SJ Jump CMJ CMJS- Tx100/CMT

Pre Post Pre Post Pre Post

10 EX 17 173.7 62.06 20.64 23.89 25.33 29.06 31.29 18.74 19.39

SD 1.6 4.9 6.5 2.08 2.9 3.5 3.3 4.05 4.02 3.5

10 CO 18 170.3 62.5 20.96 22.33 23.02 28.44 28.83 16.18 16.48

SD 0.8 3.8 2.6 2.01 2.8 1.8 2.7 2.6 4.6 4.2

Graphic 1. All groups' graphic presentation

Analyses

In tab.1 are presented in general the average data of the tests practiced to the volleyball players of two groups of the study, where the Experimental (EX) group compared to the Control (CO) group have difference in BH 173.7 ±3, BW62.05±2, BMI 20.96%±0.1.The jumps in the test performance,, the positive energy and the elastic energy were calculated by using the Komi & Bosco [2, 261-265] method. The positive energy (Epos) provided from the evaluation of the bended leg jump/squat/rep-resents the contractual performance over pure concentric contraction. Squat Jump test provides a part of the quick jump ability for developing a fast explosive force. The Countermovement Jump test, pro-

vides quick measure of the strength of the jump [6, 60-78]. The Pearson correlation shows for SJ and CMJ tests, a strong and positive correlation. The SJ correlation between the two groups even if its is technically positive the Value R=0,004, the relation between the two variables is weak and closer to the value zero and the value of R2, determining coefficient is 0. While the CMJ correlation between the two groups in time the value of R=-, 1016 even though technically is a negative correlation the relation between the variables is weak and closer to value zero. The R2 value, determining coefficient, is 0, 0128. From what we can see in tab.1, the EX group has had a significant growth compared to the control group. According to C. BOSCO the differ-

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Performance of the vertical jumps ability influenced by plyometric exercises in female volleyball players

ence between CMJ and SJ test has proposed the assessment of “elastic quality” of the athletes in teams using the concept of “elasticity index” that comes from the difference of these tests. The well managed capacity from the elastic energy corespondts to 8-10 cm. The difference between these two tests, is called the fast power index. And by applying the formulas (CMJ-Sj)x100/CMJ we gain the elasticity

coefficient expressed in%, is an indicator of the accumulated energy capacity as a result of the elastic muscular extension (eccentric) that precedes the muscular contraction (concentric), shows the obtained team values. Jumps of CMJ and SJ type are needed and if these athletes don’t demonstrate to have these type of features, means that they need a better training to develop fast power index.

Table 2. - The general table of the SJ tests in the platform GRFP

Nr EXPERIMENTAL SJ PRE F max KN P max kW V max m/s JH m

10 Average 1.49 2.41 2.15 0.39

Max. 1.88 2.82 2.32 0.52

Min. 1.14 2.05 1.97 0.29

Nr EXPERIMENTAL SJ POST F max KN P max kW V max m/s JH m

10 Average 1.26 2.48 2.3 0.44

Max. 1.72 3.07 2.57 0.46

Min. 1 1.91 2.15 0.31

Nr CONTROL SJ PRE F max KN P max kW V max m/s JH m

10 Average 1.46 2.38 2.05 0.39

Max. 1.17 2.79 2.24 0.42

Min. 1.12 2.05 1.97 0.29

Nr CONTROL SJ POST F max KN P max kW V max m/s JH m

10 Average 1.45 2.26 2.16 0.40

Max. 1.18 2.80 2.29 0.39

Min. 1.13 2.05 1.97 0.29

Table 3. - The general table of the CMJ tests in the platform GFRP

Nr EXPERIMENTAL CMJ PRE F max KN P max kW V max m/s JH m

10 Average 1.59 2.47 2.22 0.33

Max. 2 2.94 2.44 0.4

Min. 1.29 2.11 2.05 0.28

Nr EXPERIMENTAL CMJ POST F max KN P max kW V max m/s JH m

10 Average 1.55 2.67 2.33 0.36

Max. 1.92 3.15 2.52 0.44

Min. 1.38 2.15 2.2 0.31

Nr CONTROL CMJ PRE F max KN P max kW V max m/s JH m

10 Average 1.52 2.34 2.18 0.29

Max. 1.86 2.84 2.36 0.4

Min. 1.39 2.11 2.40 0.28

Nr CONTROL CMJ POST F max KN P max kW V max m/s JH m

10 Average 1.55 2.41 2.21 0.31

Max. 1.65 2.97 2.42 0.36

Min. 1.34 2.12 2.3 0.25

Data analyses

The F max, P max, V max and Jump High data of the below extremities in the volley players was registered in the GFRP platform with a connected micro computer. The participants used the maximal force to jump as high as they can. During

the jump, the players stayed in the force platform used in the study. Two of the ANOVA measurement factors were used to test the training differences in group and in time, before and after testing. The differences variation was in the high jump force and maximal power. The Alpha level was set

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Section 11. Physical Education

p < 0.05 for all comparisons. Therefore the tests were used for evaluating the changes in the max force and max power during the 12 weeks training of the plyometric exercises. The Pearson system was used for calculating the changes of the jump percentages in CMJ and SJ tests of power, force between the two groups. The correlation had R=0,8603 values between F max and P max in SJ test and shows

that is a strong positive correlation, which means that the F max results are diverse from the P max result (and vice versa). The eR2= 0,3721value, significant coefficient. While the F max and P max correlation in the CMJ test technically is a negative correlation, where r=0.7319 the relation between the variables is weak and closer to the value zero. The value of the defying coefficient is R2=0, 0938.

Table 4. - The general table of the Drop Jump 40cm test in the GFRP platform

Nr Group EX F max Pre kN Post P n Pre w/ ax kg Post Time Contact TCs Pre Post Air Tim Pre e (TA)s Post TA/ Pre TC s Post

10 Average 2.57 2.37 24.85 25.86 0.358 0.376 0.448 0.463 1.3 1.36

Max. 4.49 4.43 30.76 34.78 0.486 0.511 0.495 0.512 1.62 2.1

Min. 1.78 1.48 18.25 19.93 0.266 0.209 0.411 0.431 0.85 0.87

Nr Group CO Fmax Pre kN Post P m Pre w/ ax kg Post TimeContact. TC Pre Post Air Tim Pre e (TA)s Post TA/ Pre TC s Post

10 Average 2.47 2.32 23.81 24.06 0.348 0.366 0.428 0.443 1.28 1.3

Max. 4.49 4.43 30.76 34.78 0.486 0.511 0.495 0.512 1.52 1.98

Min. 1.56 1.38 17.25 18.93 0.266 0.209 0.411 0.431 0.65 0.77

Discussion

The vertical jumps of the DJ type are a training style developed in order to improve force, power and velocity. The result of this study demonstrates that the experimental group has clearly improved the vertical jump in height in comparison with the control group. The improvement may be attributed to the growth of the positive energy. Our result suggested that CMJ and DJ training are both effective for improving the vertical jump abilities. [9, 85-89] found out that also plyometric training is not more effective than CMJ training for improving the vertical jump abilities. But we think that the applied CMJ test is as effective as DJ training in this context. The results of this study specifies that the mechanism for improving the jump abilities by following the DJ training and that is of the plyometric exercises type. The DJ training can enhance the neuromuscular factors that affect the training specifics. As it is shown in the tables 1 and 2, the groups show that SJ and CJM test improve only the vertical jump in height and the production of positive energy in jump. While the experimental group trained in plyometric exercises of DJ40cm type, improves the jump in height as well as in max power and max force. Our results sustain the hypothesis that DJ training is superior towards the 12 weeks training of the experimental group dif-

ferent from the control group that hasn’t been scheduled for training of the DJ 40cm plyometric type. The majority of training studies have not pointed to the other differences that may have been influenced by the training programs. [10, 36-41] in 7 weeks training, measured the vertical jumping ability through the Sergeant jump and did not evaluate changes in the positive energy or effects in the elastic energy. In a 12 weeks study evaluated the subjects/individuals with specific programs but presented only vertical jumps height and did not discuss the changes in the positive energy or the effects in the elastic energy.

Conclusion

The result of the current study showed that 12-week program clearly improved the vertical jump height and production of positive energy for both trained. To us it resulted acceptable the 12 weeks training of the plyometric exercises on these age groups. The plyometric training is connected to the power production of the lower part of the body and is applied with the DJ test and the players perform with higher power in “drop jump” than “countermovement jump”. The coaches need for exercises that spend less time and in the same time help players to improve the jumping abilities, excluding the damage risk “Drop Jumping” is thought to complete these needs.

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60 cm Drop Jump test assessment in 17 years old volleyball players in Albania under the influence of Plyometric Training

References:

1. Bosco C., P. Komi, 1981. Prestretch potentiation of human skeletal muscle during ballistic movement. Acta Physiol. Scand. 111: 135-140 p.

2. Komi, P. V.,&C. Bosco.,1978.Utilization of stored elastic energy in leg extensor muscles by men and women. Med. Sci. Sports 10: 261-265 p.

3. Sheppard, M.&Chapman, D.&al.2009.U. Twelve-month training-induced changes in elite international volleyball players.Journal Strength Cond Res.volum 23, nr 7, 2096-2101 p.

4. Blattner, S. E., and L. Noble. (1979)Relative effects of isokinetic and plyometric training on vertical jumping performance. Res. Quar. 50: 583-588 p.

5. Clutch, D., M. Wilton, C. Mc Gown, and G. R. Bryce. (1983)The effect of depth jumps and weight training on leg strength and vertical jump. Res. Q. Exerc. Sport 54: 5-10 p.

6. Cometti, G., Cometti. D., 2009”LaPliometria (origini, teorie, allenamento)2a edizione italiana (Tivoli) Capitolo V; I TEST. Test di Bosco, 60-78 p.

7. Marell, M., Risalti, M.,2007. Il librodeiTest, Le prove di valutazionefisica per tuttigli sport; 80-85pp.

8. Carmelo Bosco Ph.D (2006).”Laforzamuscolare”Aspetti Fisiologici ed Applicazioni Pratiche” (Rome) Capitolo IV, La Forza Explosiva,103-110 p.

9. Daniel J. Gehri, Mark D. Ricard, Douglas M. Kleinerl, and Donald T. Kirkendall Journal of Strength and Conditioning Research, 1998, 12 (2), 85-89. National Strength & Conditioning Association A Comparison of Plyometric Training Techniques for Improving Vertical Jump Ability and Energy Production.

10. Adams, T. (1984). An investigation of selected plyometric training exercises on muscular leg strength and power. Track Field Qnar.Rear. 84 (1): 36-41p.

Lleshi Enkeleida, Sports University of Tirana PhD student at Sport Sciences Research Institute Sports University of Tirana Email: [email protected]

60 cm Drop Jump test assessment in 17 years old volleyball players in Albania under the influence of Plyometric Training

Abstract: The assessment of vertical jump through 60cm Drop Jump Test under the influence of Plyometric Training (PT) is the main purpose of this study. PT has been conducted for 12 weeks with volleyball players in Albania. The data were taken prior to afterwards PT for 12 week. 20 volleyball players Experimental (EX) group 10 players with average Age 17±1, BH186.3±5.1, BW 74.3 ± 6.1, BMI 22.25% ± 3.4 and also Control group (CO) 10 players with average Age17±0.9, BH 185.9 ± 8.4, BW 70.2±8.6, BMI 20.37%±2.01 performed the test DJ60cm in the platform Leonardo® Ground Force Reaction Plate (GRFP) which express Force max (kN), Power max (w/kg), Time Contact (TCs), Air Time (TAs), TA/TCs. The 12 week programme was applied only by the EX group in 2 sessions in each week aiming plyometric exercises and 3 sessions with ball, while the CO group developed only 5 training session with ball. Both volleyball groups performed lower values at the beginning of the tests. The results obtained from PT in GRFP after 12 weeks showed an improvement in lower extremities Fmax and Pmax. EX group showed statistically proficiency improvement on 60cm DJ jump test from CO group. Plyometric exercises as part of a programme designed for volleyball players are necessary for improving vertical jump skills of the teams but also of the individual himself.

Keywords: drop jump, volleyball, plyometric training.

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