The Effect of Plyometric Trainings on the Leg Muscle Power

Enhancement of Women’s Volleyball Junior Athletes

Bayu Santoso

, Hari Amirullah Rachman

Departement of Sport Science, Graduate School,

Universitas Negeri Yogyakarta, Yogyakarta, Indonesia

Keywords: Front Jump and Side Jump Plyometric Training, Leg Muscle Power.

Abstract: The purpose of this research is to find out the effect of plyometric training on the leg muscle power

enhancement of the women’s volleyball junior athletes at Yuso Yogyakarta. This research employed

experiment methods with the design of “two group’s pre-test post-test design”. The population in this

research were the women’s volleyball junior athletes at Yuso Yogyakarta which consist of 30 athletes. The

sampling technique was purposive sampling, with following criteria: (1) The chosen athletes have been

training more than three years; (2) The athletes were between 14 to 18 years old; (3) The athletes were able

to participate in the conducted pre-test, treatment, and post-test. As a result on that consideration, 18 out of

30 athletes were chosen as the participants. Muscle leg power requires vertical jumps with a jump aid and

Harman Formulation. The data were analyzed using T test. The result of analysis showed that: (1) There

was a significance effect of the front jump plyometric training on the leg muscle power of the women’s

volleyball junior athletes at Yuso Yogyakarta with t count 3.357 > t table 2.306, significance value of 0.010

< 0.05, enhancement percentage of 8.586%. (2) There was a significance effect of side jump plyometric

training to the leg muscle power enhancement of the women’s volleyball junior athletes at Yuso Yogyakarta

with t count 3.577 > t table 2.306, significance value of 0.007 < 0.05, and enhancement percentage of

3.976%. (3) The front jump plyometric training was more effective to increase leg muscle power with the

different percentage of 4.610%.

1 INTRODUCTION

Volleyball is one of favourite sports in Indonesia,

including in Yogyakarta. In its development, there

have been some volleyball clubs in Yogyakarta

which actively participate in the regional, province

to national levels of championship. Many teenagers

joining the clubs have won the championships

ranging from junior to senior levels. Each volleyball

club in Yogyakarta is currently in the race to

develop its athletes which are competitive and

eligible in any event and are excellent in any

championship.

In volleyball games, there are several factors that

influence athletes to excel in order to obtain

maximum achievement, namely techniques, tactics,

and mental as well as physical condition. LA84

Foundation (2012: 57) describes the components of

physical training in volleyball games. They are

divided into four categories: endurance, speed,

strength and power. All those physical components

in volleyball are athletes’ need to achieve maximum

performance. Without having a good physique,

volleyball athletes will find it hard to achieve

maximum performance.

Good physical ability will help athletes to master

volleyball techniques, i.e. the smashing technique

which is the main weapon of a volleyball player to

turn off an opponent and get points. When

performing this technique, it takes a high jump as

well as a hard and directed blow. For that, the

players need power of their legs, arms, back and

stomach. Another technique is called blocking. This

technique is also the main weapon for defense to

stem the opponent's smash and turn off the ball in

the opponent's area. In addition, this also requires

high jumps and good movement techniques.

The physical component especially the power of

legs is very influential for volleyball athletes in

jumping when performing smashing and blocking

techniques so as to produce a good high jump that

can help athletes in doing good smashes and blocks.

268

Santoso, B. and Rachman, H.

The Effect of Plyometric Trainings on the Leg Muscle Power Enhancement of Women’s Volleyball Junior Athletes.

DOI: 10.5220/0009784402680272

In Proceedings of the 3rd Yogyakarta International Seminar on Health, Physical Education, and Sport Science in conjunction with the 2nd Conference on Interdisciplinary Approach in Sports

(YISHPESS and CoIS 2019), pages 268-272

ISBN: 978-989-758-457-2

Speed and strength when jumping are also important

factors in volleyball.

Power training methods can use a variety of

strength training or plyometric exercises. Pliometrics

is one method of trainings to enhance the power of

legs and the height of jumping. Plyometric training

is very easy for athletes to do during training in the

field. However, the structured pliometric exercises

are rarely applied during training sessions.

Plyometric training has many benefits for

volleyball athletes, because volleyball games that

require good power. Thus, this training can help the

athletes when smashing and blocking by increasing

the jump height. Donald A Chu (2013: 36) explains

that proper pliometric movements have a large

impact on increasing power related to sports

involving Stretch-Shortening Cycle (SSC). Front

jumps and side jumps are the forms of pliometrics

that emphasize speed and height of jump.

Yuso is a volleyball team in Yogyakarta which

has a tiered coaching. The training program is

distinguished from the level of beginners, teens,

juniors to seniors. In its implementation the

pliometric training program has not been maximally

given to junior level athletes. In preparing an

exercise program, pliometric training needs to be

studied in terms of its dose of exercise that covers

the training load, number of sets, rhythm, repetition,

and recovery. Those elements are very influential to

determine the achievement of a training goal. The

preparation of a structured and systematic training

program has not been done by many trainers to

achieve the training objectives.

Based on the experience during microcoaching

and field practice education at the Yuso club, many

junior athletes have not got a good leap. In this case,

there are many factors which help athletes to have a

good leap, one of which is the athlete's physical

strength. The junior athletes in that club have not

got good physical strength so that they mostly

cannot make a good jump.

The forms and types of pliometric training are

needed to be presented by volleyball coaches to

avoid the athletes’ boredom. Plyometric front jump

and side jump exercises are the examples of

pliometric training to increase the leg muscle power

of volleyball athletes. Variations in this exercise are

needed when athletes feel bored with strength or

speed training.

Based on the underlying background above, a

research was conducted in Yuso volleyball club

Yogyakarta aimed at using pliometric front jump

and side jump exercises to increase the athletes’ leg

power. The research was entitled “The Effect of

Plyometric Trainings on the Leg Muscle Power

Enhancement of Women’s Volleyball Junior

Athletes".

2 RESEARCH METHODS

2.1 The Type of Research

This research was a quasi-experimental research,

meaning that the sample was not quarantined or

dormant. According to Suharsimi Arikunto (2010:

36) experimental research is a study that is intended

to determine whether there is a result of something

imposed on the subject. The research design used in

this study was "Two Groups Pre-test Post-test

Design"; the design of the study that had a pretest

before being treated and posttest after being treated.

2.2 Time and Place of Research

The research was conducted on February 18 - March

29, 2018. The pretest was held on February 17, 2018

and posttest on March 30, 2018. The treatment was

carried out for 18 meetings with a frequency of

exercise of three times in a week; on Tuesdays,

Thursdays and Saturdayso at the Yuso volleyball

court in Yogyakarta.

2.3 Research Subject

The population in this study were Yuso Yogyakarta

volleyball athletes, totaling 35 athletes. According to

Sugiyono (2011: 120), sample is part of the numbers

and characteristics possessed by the population. The

sample can be taken from a population. According to

Sugiyono (2011: 126) purposive sampling is a

technique of determining samples with certain

considerations. The criteria for determining this

sample include the Yuso's female volleyball athletes:

(1) who has been training for more than 3 years, (2)

whose ages are between 14 to18 years old, (3) who

are willing to take the pretest, treatment and posttest.

Based on these criteria, 18 athletes were chosen as

they were suitable to be the research participants.

2.4 Instruments and Data Collection

Techniques

The research instrument is a tool used by the

researchers in collecting data so that their work is

easier and the results are better, in the sense of being

meticulous, complete, systematic, and easy to

process (Suharsimi Arikunto, 2010: 192). The

The Effect of Plyometric Trainings on the Leg Muscle Power Enhancement of Women’s Volleyball Junior Athletes

269

instrument was for the initial measurement (pretest)

and final measurement (posttest) using the vertical

jump test from Brian Mac (2012: 4) with the

Harman formula. The purpose of the test is to

measure the leg muscle power.

2.5 Data Analysis Technique

The data in this study were analyzed by conducting

normality, homogeneity and hypothesis testings with

the help of SPSS 20.

2.5.1 Normality Test

The purpose of the normality test is to test the

normal distribution of the data to be analyzed.

2.5.2 Homogeneity Test

The purpose of the homogeneity test is to ensure that

the groups that make up the sample come from a

homogeneous population.

2.5.3 Hypothesis Testing

After the prerequisite test is fulfilled, the hypothesis

is tested. Hypothesis testing uses the t-test with the

help of SPSS 20, namely by comparing the mean

between pretest and posttest. If the value of t count

is smaller than t table, then Ha is rejected, if t count

is greater than t table then Ha is accepted.

3 RESEARCH RESULTS AND

DISCUSSION

3. 1 Research Result

The results of data analysis could be described as

follows:

3.1.1 Group A (Front Jump Pliometric

Exercise)

Group A for front jump plyometric training consists

of 9 athletes. The results of the study are known as

follows. Based on the data analysis, the pretest on

the leg power resulted in the mean value of 794,689,

minimum value of 592.2, and the maximum value of

1028.8, while the posttest resulted in the mean value

of 826,922, minimum value of 608.3, and maximum

value of 1038.5. In addition, the pretest on vertical

jump resulted in the mean value of 44.22, minimum

value of 38, and maximum value of 55, while the

posttest resulted in the mean value of 46.78,

minimum value of 42, and the maximum value of

56.

3.1.2 Group B (Pliometric Side Jump

Exercise)

Group B for side jump plyometric training consists

of 9 athletes. The results of the study are known as

follows. Based on the data analysis, the pretest on

the leg power resulted in the mean value of 787,989,

minimum value of 542.1, and maximum value of

1016.9, while the posttest resulted in the mean value

of 819.322, minimum value of 581.7, and the

maximum value of 1017.4. In addition, the pretest

on vertical jump resulted in the mean value of 44.33,

minimum value of 39, the maximum value of 53,

while the posttest resulted in the mean value of

45.44, minimum value of 41, and maximum value of

53.

3.1.3 Prerequisite and Data Analysis of the

Test Results

The normality test was done using the Shapiro-Wilk

formula with the SPSS 20. The data are said to be

normally distributed if the significance value

obtained is greater than 0.05. The following are the

results of normality test calculations:

From the data above, it can be seen that all data

(pretest and posttest) have p value (Sig.) of more

than 0.05 (> 0.05). It can be concluded that the data

are normally distributed.

The purpose of the homogeneity test is to find

out the similarity of variance or test that the data

obtained come from homogeneous samples.

From the table, the Sig. value scores 0.884 and

0.814 which are greater than 0.05. This means the

data are homogeneous.

The hypotheses proposed in this study are: (1)

There is a significant effect of applying plyometric

front jump training on enhancing the leg muscle

power of women’s volleyball junior athletes at Yuso

Yogyakarta. (2) There is a significant effect of

applying plyometric side jump training on enhancing

the leg muscle power of women’s volleyball junior

athletes at Yuso Yogyakarta. (3) Polyometric front

jump exercises are more effective than side jump

exercises in increasing leg muscle power.

The results of the t-test on group A, it can be

seen that t count values 3.357 and t table values

2.306 (df = (n-1) = 9) with a significance value (p)

of 0.010, and a percentage increase of 8.586%.

Therefore, this result showed that there is a

significant difference in group A (front jump

training).

YISHPESS and CoIS 2019 - The 3rd Yogyakarta International Seminar on Health, Physical Education, and Sport Science (YISHPESS

2019) in conjunction with The 2nd Conference on Interdisciplinary Approach in Sports (CoIS 2019)

270

From the results of the t-test on group B, it can

be seen that t count values 3.577 and t table values

2.306 with a significance value of p of 0.007.

Because t count 3.577 is > t table 2,306, a

significance value of 0.007 is < 0.05, and a

percentage increase of 3.976%, this result showed a

significant difference in group B (side jump

training).

From the results of the t-test it can be seen that t

count values 2.455 and t table values 2.306 with a

significance value of p of 0.040. Therefore t count

2.455 is > t table 2.306, the significance value 0.040

is <0.05, and the difference in percentage increase is

4.61%. This means that there are significant

differences between group A and group B. Thus, the

front jump training applied for group A is more

effective in enhancing leg muscle power.

3. 2 Discussion

This study aimed at determining the effect of front

jump and side jump pliometric trainings on

enhancing the leg muscle power of women’s

volleyball junior athletes at Yuso Yogyakarta.

The statistical results show that group A athletes

who received the treatment of pliometric front jump

training and group B who received treatment for

pliometric side jump training for 18 meetings both

experienced the enhancement of leg power. By

joining the training process for 18 times, it can

enhance the power of the legs significantly.

3.2.1 Increased Group a Leg Muscle Power

(Front Jump Exercise)

The results of the analysis showed that there were

effects of leg power before and after the pliometric

front jump exercise. This was indicated by the value

of t count 3.357 and t-table 2.306 df = 8, while the p

value is 0.010 (table 5). Because t count 3.357 is > t

table 2.306 and p value 0.010 is <0.05, it means that

there is a significant effect.

This means that the front jump pliometric

exercise has a significant influence on the leg power

enhancement of women’s volleyball junior athletes

at Yuso Yogyakarta. This enhancement is due to the

activity of pliometric front jump, i.e. is to jump

forward in explosive movements with different

heights every week. The example of pliometric front

jump training is to jump in a motion that explosively

passes through as many as 10 obstacles with a height

of 30cm by paying attention to repetitions, sets,

recovery, and intervals. Each repetition is given a

complete recovery time (t.r) and interval time (t.i)

(complete recovery). Comparison of recovery time

(t.r) 1: 5, while for interval time (t.i) 2 minutes. The

pliometric front jump exercise is similar to a vertical

jump test, so that the trained muscular spindles will

be the same.

3.2.2 Increased Group B Leg Muscle Power

(Side Jump Exercise)

The results of the analysis showed that there was a

significant influence of side jump training on

enhancing the leg power of women’s volleyball

junior athletes at Yuso Yogyakarta. This was

indicated by the value of t count of 3.577 and t table

2.306 while the significance value of p 0.007 (table

6). Because t count 3.577 is > t table 2,306 and

significance value p 0.007 is <0.05, it means that

there is a significant effect.

The athletes’ leg power has increased in side

jump pliometric exercises because this movement

involves Stretch Shortening Cycle (SSC). This is in

accordance with the statement of Donald Chu (2013:

36) that a proper plyometric movement involving

Stretch Shortening Cycle (SSC) has a large impact

on increasing power.

3.2.3 Front Jump Exercise is More Effective

in Increasing Leg Muscle Power

The results of the analysis showed that there is a

significant difference on the leg power enhancement

of women’s volleyball junior athletes at Yuso

Yogyakarta. This was indicated by the increase in

the percentage of group A (front jump exercises) by

8.586% greater than the increase in the percentage of

group B (side jump exercises) which is 3.976%, with

a difference in percentage of 4.610% (table 7).

Plyometric front jump exercises are more effective

because in these exercises, the athletes move

forward to jump high in accordance with the

movement of the leg power tests including vertical

jumping and muscular spindle training.

4 CONCLUSIONS AND

SUGGESTIONS

4.1 Conclusion

Based on the research findings and discussions,

some conclusions can be drawn as follows: a) There

is a significant effect of applying plyometric front

jump training on enhancing the leg muscle power of

women’s volleyball junior athletes at Yuso

Yogyakarta; b) There is a significant effect of

The Effect of Plyometric Trainings on the Leg Muscle Power Enhancement of Women’s Volleyball Junior Athletes

271

applying plyometric side jump training on enhancing

the leg muscle power of women’s volleyball junior

athletes at Yuso Yogyakarta; c) Polyometric front

jump exercises are more effective than side jump

exercises in increasing leg muscle power.

4.2 Implications of Research Results

Based on the research findings, discussions and

conclusions, there are several implications that can

be stated as follows: 1) It is needed to provide good

understanding for volleyball coaches in particular

and other kinds of sport coaches whose movements

resemble volleyball games such as basketball,

badminton, soccer and other sports in general about

the effectof pliometric front jump training on

enhancing athlete's leg power; 2) Ront jump training

is a variation of training used to increase the

athletes’ power especially their power of legs.

4.3 Suggestion

By referring to the research findings and

discussions, it suggested that: 1) It is best to do a

research using larger samples; 2) The research

should be carried out when the athletes have no

activity or no event held in the near future; 3) The

presence of strength training is needed before

applying plyometric exercise, because strength is the

prior requirement for plyometric exercise; 4) There

is a need for other researchers to conduct the

plyometric training for the upper body to increase

the power of athletes.

REFERENCES

Arikunto, S., 2010. Prosedur Penelitian Suatu Pendekatan

Praktek. Rineka Cipta. Jakarta.

Chu, D., 2013. Plyometrics. Human Kinetics. United

States.

LA84 Foundation, 2012. Volleyball Coaching Manual,

LA84 Foundation, United States.

Mac., B., 2012. Sargent Jump Test. Diakses tanggal 19

Mei 2016 dari www.brianmac.co.uk/sgtjump.htm

Sugiyono, 2011. Metode penelitian Kombinasi (Mixed

Methods). ALFABETA, Bandung.

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2019) in conjunction with The 2nd Conference on Interdisciplinary Approach in Sports (CoIS 2019)

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