THE CORRELATION BETWEEN LEG AND ARM MUSCLE POWER TOWARDS THE RESULTS OF OPEN SMASH ABILITY ON VOLLEY BALL EXTRACURRICULAR
 
Hakim Irwandi Marpaung1, Bambang Priyonoadi2
1Graduate School Program, Yogyakarta State University, Sleman, Yogyakarta, Indonesia
2Graduate School Program, Yogyakarta State University, Sleman, Yogyakarta, Indonesia
hakimirwandimarpaung@gmail.com, bambang_pa@uny.ac.id

Keywords	: Leg muscle power, Arm muscle power, Open Smash	

Abstract		:This study aimed to determine the correlation between leg muscle and arm muscle power with the results of the open smash ability. The number of the samples were 10  students from all male who belonged to volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa, Sumatra Utara, which was obtained by conductinhtotal sampling technique. The instruments which were used in this study were vertical jump, ball medicine, and volleyball smashes.First hypothesis test presented the coefficient correlation as stated rx1y = rcount0,822 > rtable0,632 dan tcount = 4,086 > ttable= 1,86. Based on the criteria of hypothesis test, it could be concluded that H0had been rejected and Hahad been accepted, which meant that there are any correlations between leg muscle and arm muscle power with the results of the open smash abilityat Nurul Amaliyah vocational school Tanjung Morawa. Determinated coefficient in the amount of 67,57%, indicated the existence of contribution from leg muscle power toward the results of the open smash ability.Second hypothesis test presented the coefficient correlation as stated rx2y = rcount0,749 > rtable0,632 dan tcount = 3,193 > ttable= 1,86. Based on the criteria of hypothesis test, it could be concluded that H0has been rejected and Hahas been accepted, which meant that there are any correlations between leg muscle and arm muscle power with the results of the open smash abilityat Nurul Amaliyah vocational school Tanjung Morawa, Sumatra Utara. Determinated coefficient in the amount of 56,10%, indicate the contribution of arm muscle power toward the results of the open smash ability.Third hypothesis test presented the coefficient of correlation as stated rx1x2y = rcount0,822 > rtable0,632 dan Fcount = 7,301 > Ftable= 4,74. Based on the criteria of hypothesis test, it could be concluded that H0has been rejected and Hahas been accepted, which meant that there are any correlationsbetween leg muscle and arm muscle power with the results of the open smash abilityat Nurul Amaliyah vocational schoolTanjung Morawa, Sumatra Utara. Determinated coefficient in the amount of 67,57%, indicate the contribution of arm muscle and leg muscle power toward the results of the open smash ability, whereas 32,43 % has been affected by other variables.

INTRODUCTION

Volley ball is a kind of sports which is played by two groups of people, where each group consists of six players. Volley ball is the majorly known sports that people are delight in doing such activity. It is a kind of sport that can upgrade the sense of recreation and performance or competition, which has been proved by many volley ball competitions in the rank of high school or even university. There are 5 technique in volley ball i.e. upper passing, lower passing, service, smash, and blocking. The research focused on open smash ability, where the object matter which affected the ability was leg muscle and arm muscle power. Regarding to the techniques, power and speed are necessary for the players, with the consequence of supporting physical fitness is mainly needed. The power of leg muscle is useful to create an optimal jump when the players in the effort of doing an open smash and the power from arm muscle is useful to increase the power and the speed while players hit the ball.
In order to mastery the basic technique of volley ball, players have to be in good physical condition, since the condition will give contribution to players and it will make easier for doing such kind of technique. Good physical condition will ease the player to obtained many achievements. Sajoto (1988:3) stated that “determining factors in order to gain an achievement in sports is obtained good physical aspects such as strength, speed, agility, coordination, power, muscle durability, healthy heart and lungs, accuracy, flexibility, reaction, and fitness”. Therefore, it can be concluded that volley ball is a kind of sport that good physical condition is the basic requirements to develop the optimal fitness, physically and mentally. By having a good physical condition, players should have intense training, correct, programmed, and consistent in order to gain an optimal achievement.  
Leg muscle and arm muscle power are very important for volley ball players, especially for smasher,since leg muscle has the main role for player in doing an optimal jump, and arm muscle is actively contribute in hitting the ball. When volley ball players have good condition of leg and arm muscle, they will have an optimal power, thus their smash will be hard to be blocked. In order to give a deadly smash to the opponents, the players have to make good position and power while smashing the ball, take the highest point to avoid opponents’ block.
According to the result of observation and interview at 10th – 30th June, 2019 with trainer or education sports teacher named Zainal Abidin, S.Pd., it can be assumed that 10 of all male volleyball extracurricular athletes at Nurul Amaliyah vocational schoolTanjung Morawa hadgained three times training in a week, at Tuesday, Thursday, and Saturday. Based on the observation, it had been known that some problems occurred during the mastery of basic techniques, such as easy to take the smash, smashis very easy to be blocked, and several failed and inaccurate smash. The researcher assumed that the problems were caused by the weak power of leg muscle and arm muscle.
Based on that problems above, researcher will take deep contemplation and research entitled“The Correlation Between Leg Muscle And Arm Muscle Power Towards The Results of Open SmashAbility on Volley Ball Extracurricular Athlete atNurul Amaliyah Vocational SchoolTanjung Morawa, Sumatera Utara.”
Indra Kasih (2016:35) stated that “Smash is an action of hitting the ball in the pointed direction within great power, along with optimal jump, enter the opponents’ field”. Gerhard Durrwacher (1982:63) also stated that “Smash is main hit in the effort of create an offensive play, in order to win the game”. Nuril Ahmadi (2007:31) stated that “Smash is an action where the hands of players fully contacted the upper part of the ball, make the pointed lines of the ball’s track within massive power and speed”. 
From quotation above, it can be explained that smash is an effort to gain a score in the gameplay, smash usually done by the front line of attack field, because only in the attack field, players are easier to make a smash through the net. Smash also can be done in the back field; however, it must be done with optimal jump from 3 metres of back line. 

Nuril Ahmadi (2007: 32) stated that, Smash can be done within some steps,steadiness, approaching, striking, and landing. Further detail of each steps will be explained as follow:
1.	Steadiness
Players stands with normal posture about 3-4 metres in the back distance of net. While players try to make step forward, they make steady little steps in their place.
2.	Approaching
Stepping forward, then take a foothold along with lowered body. Both of arms already on each side of the body, then pull the arms into the backside followed by explosive jump, ready for striking the ball by posturing a swing from behind to front side.
3.	Striking
While in the air, players should be able to reach the ball and then hit the ball with great power from dominant hand. The positioning of the hand must be focused on how palm can make a whip move, either arms or hand. The hit can be optimalized, if the whip movement followed by strong foothold, lowered body, and controlled standing. This position must be done in one harmonic and explosive movement.
4.	Landing
After the ball has been successfully hit, the smasher is ready to land. Landing must be done with good positioning use two legs and steadiness.

Analysis of Smash Movement
a. Process of Steadiness, steadiness depends on the track of passing ball, about 3-4 metres from the falling point. When we jump, we must take a full awareness on how our legs has been positioned, the leg which become the hold must be positioned in front of another leg. The movement that occurred called lower leg flexi movement (fleksi genu).
b. Process of Jumping, after the process of steadiness, smasher continue the process with stepping movement. This process are extended process from lower leg flexi movement use particular parts of the muscle (extremitas inferior muscle)i.e.m.rectus femoris, m.vastus medialis, m.vastus lateralis, m.biceps femoris, dan m.gastronemius.
When players take explosive jump, it must be done continually. The starting stephave to be coordinated with the arms which has been swang from behind the back of the body, bending the knee, then both of arms must be massively jolted through the thigh, starting the explosive spread of the legs, shoulder follow the explosive movement.
Shortly after jumping when the body floated in the air with position swelled backward, which is the hyperextension motion. The soles of the feet, ankles, pelvis, and toes are moved in harmony to obtain a perfect range of motion to create explosive movements and vertical jumps.
c. Process of Striking, in striking the ball, this skill is the work of hand eye coordination in an effort to adjust the right time from the highest jumping range to the presence of the falling ball. The active wrist jerks forward with the palm and fingers closing the ball which is a flexion of the wrist by involving the flexor carpi radialis muscle, the extensor carpi ulnaris muscle and the extensor digitorum. After exposure to the ball, the beating arm makes a further movement towards the midline of the body or the extended range of arms, which involves the deltoid muscle, the pectoralis major muscle, and the lactimus dorsi muscle, followed by bending gestures involving the abdominis.
The correct strike will result in a hard and fast ball going to the ground with a fast spin towards the top (top spin). When striking, the muscles directly involved are shoulder groups such as deltoid, travezeus and triceps brachii and lower arm muscles such as flexor carpi radialis muscle, extensor carpi ulnaris muscle and extensor digitorum.
d. Process of Landing, the next movement after striking the ball above the net is landing with the two legs slightly bent (lower limb flexion motion) that are flexible to dampen the leg. The way to land in each smash is the same when the upper body bends forward, the foot is directed forward to maintain the balance of the athlete landing on both legs with a slight bend.
Open smash is a variation of attack techniques in volleyball that is quite difficult to do, because it has a complex movement. The movement consists of elements of speed when running the starting steps, jumping, coordinating with the ball when it will hit the ball and the strength when it will land. A mistake that often occurs or that is done by a player is the absence of explosive power or power in making open smash / spike movements. Explosive power or leg power greatly affects the results of spikes where leg muscle power and arm muscle power are very important in volleyball games, especially for smasher. Thus, by having good leg muscle power and arm muscle power, the smash will be difficult to block. In order to produce a deadly strike to the opponent's field, the player must smash when the ball is at maximum height to avoid block from the opponent.
As stated by Indra Kasih (2016: 45) suggests the special characteristics of a normal smash (open smash) are: the ball (bait) is high enough to reach 3 m above, the distance of the ball trajectory that is fed ranges between 20-50 cm from the net, the point of the falling point of the ball that is fed around the middle between the feeder and the smasher measured from the projection line of the smasher to the net, the first step starts after removing the feeder by looking at concentrating the ball, reaching and hitting the ball as high as the net.
From a number of opinions above, the writer concludes that the skill of open smash / open spike is one of the blows that has a fairly high ball characteristic, namely 3 to 4 meters which means that a spiker must have a high enough jump quality in purpose that the spike / smash results are more maximal.
According to Harsono (1988: 200) explosive power (power) is the ability of muscles to exert maximum strength in a very fast time. Then Bompa (1983: 57) states, "explosive power is the result of an alloy of the strength and speed of muscle contraction". Whereas Sajoto (1988: 85) argues that muscular power is the ability of a person to carry out maximum strength with his effort being deployed in the shortest amount of time. 
Based on the opinion above, it can be concluded that power is the result of strength and speed, namely the ability of the muscle to exert or exert maximum strength in a very short time. If each 2 individuals can lift a weight of 70 kg, but one can lift it faster than the others, then that person has better power than the person who lifts it more slowly. 
Power of the leg muscles greatly determines the ability of a player to perform various movements in playing volleyball, which is one of his movements jumping when he wants to do a smash. In the game of volleyball to do a power, the maximum speed of smash is one of which is determined by good explosive power, in other words the player who has the explosive power of leg muscles is one component of a very important physical condition, which must be possessed in volleyball. The part of the leg muscle (inferior extremity muscle) is m.rectus femoris, medial vascular, lateral mucus, m.biceps femoris, m.gastronemius, m.soleus. Leap when doing a smash really needs good leg muscle power, by having good leg muscle power most likely will result in a high jump and to overcome the net height so that it will be easier to smash when floating in the air.
Regarding to to the explosive power of the leg muscles, the explosive power of the arm muscles is also a very important thing an athlete must have in carrying out volleyball smashes. Where an athlete must be able to hit the ball quickly and strongly so that the opponent is difficult to return the ball. 
Bompa (1993: 57) states "power is the result of the combination of the strength and speed of muscle contraction. While Indra Kasih (2016: 52) suggests that power is the ability to do business optimally in the shortest time - in short. 
Thus, it can be stated that "power is one of the most important traits for skills (performance) in sports and maximum power (maximal power) or called exsplosive power is the maximum combination of speed and strenght. Muscle explosive power is very important to do a motion activity in every sport. The explosive power of the arm muscles will determine how hard an athlete striking, how far they throw or repuls. The explosive power of the arm muscles is influenced by the ability of the arm muscles, while the part of the arm muscles (superior extremity muscle) is m. Trapezius, m.deltoideus, m.pectoralis major, m.biceps brachii, m.triceps brachii, m.brachialis, m.brachioradialis, m.pronator teres, m. flexor carpi radialis, m.flexor digitorum superficialis tendines.
		
RESEARCH METHODOLOGY
As stated earlier, this study aimed to determine the correlation of leg muscle and arm muscle power with the results of the open smash ability in volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa, Sumatra Utara. This study implemented descriptive methods by conducting test and measurement techniques.

Instrument
The data in this study were variableswhich were correlated on leg muscle power, arm muscle power, and the results of the ability to open smash volleyball collected by tests and measurements.

Vertical Jump            Field ofSmashTest

Pulse Medicine

Figure 1: Instruments of the testto gain the score

Data Analyzing Technique
The data obtained in this study were processed using simple correlation, multiple correlation and before testing hypotheses the requirements test was carried out, namely the data normality test and linearity test.

FINDING AND DISCUSSION
Description of Research Data
The following is a description of the raw data of the research results which include data on the number, average value, maximum, minimum value and standard deviation.

1.	The Result of Leg Muscle Power Test
Table1:The Result Data of Leg Musle Power Test
Statistic	X1	
Maximum Value
Minimum Value
Average Value
Standard Deviation	62
40
50,2
7,35	

2.	The Result of Arms Muscle Power Test
	Tabel 2: The Result Data of Arms Muscle Power Test
Statistic	X2	
Maximum Value
Minimum Value
Average Value
Standard Deviation	524
424
457,2
35,00	

3.	The Result of Open Smash Test
Table3:The Result Data of Open Smash Test
Statistic	Y	
Maximum Value
Minimum Value
Average Value
Standard Deviation	129,10
73,16
100
14,73	

Analysis Requirements Test
Test requirements for analysis is required in the analysis of statistical data to make the data collection can be used in this study. Requirements test for the analysis data were normality test and linearity test.
Variable	Average andStandard Deviation	Lo	L table		Ket	
Leg Muscle Power	= 50.2
S = 7,35	0.168	0.258	0,05	Normal	
Arms Muscle Power	= 457,2
S = 35,00	0   0,247	0.258	0,05	Normal	
Result of Open Smash	= 100
S= 14,73	0,210	0.258	0,05	Normal	

1.	Result of Normality Test
Table4. Normality Test

Normality test of data by using the reliability test, from table 4, it can be seen that the values ​​for each variable are all greater than theL table, Ltable= 0.258 with n=10 dan level α= 0,05. because Lcount< Ltable can be concluded that the sample comes from a population that is normally distributed.
No	Research Variable	Fcount	Sig	Info	
1	 (X1) - (Y)	84,736	0,083	Linier	
2	 (X2) - (Y)	0,215	0,932	Linier	

2.	Result of Linearity Test
Tabel 5 : Linearity Test
Source: Output SPSS 18.0
Based on the results of data analysis, it can be seen that the correlation between leg muscle power and the results of the open smash ability is linear, with an F value of 84.736 and significant 0.083 (sig> 0.05). The correlation between arm muscle power and the results of the open smash ability is linear, with an F value of 0.215 and significant 0.932 (sig> 0.05).

Hyphotesis Test

1.	The correlation between Leg Muscle Power (X1) towards Open Smash Ability Results (Y) in Male Volleyball Extracurricular Athletes at Nurul Amaliyah Vocational School Tanjung Morawa, North Sumatra.

Table 6. Correlation of coeficient X1 with Y variable
Correlation	Correlation of coeficient, n=10	Amount of t, dk=10-2=8, α = 0,05	Determination (R2)	
	rcount	rtable	tcount	ttable		
rx1y	0,822	0,632	4,086	1,86	
67,57%

The results of testing the first hypothesis obtained a correlation coefficient of rx1y = rcount 0.822> rtable 0.632 and tcount = 4.086> ttable = 1.86. Based on the testing criteria of the hypothesis that H0 is rejected Ha accepted, then in this study concluded that there is a positive and significant correlation between leg muscle power towards the open smash ability results of male volleyball extracurricular athleteat Nurul Amaliyah vocational school Tanjung Morawa, North Sumatra. The determination coefficient of 67.57% explained that leg muscle power contributed 67.57% to the results of the ability of open smash.

2.	The correlation between Arm Muscle Power (X2) towards Open Smash Ability Results (Y) in Male Volleyball Extracurricular Athletes at Nurul Amaliyah Vocational School Tanjung Morawa, North Sumatra.

Table7. Correlation of coeficient X2 with Y variable
Correlation	Correlation of coeficent, n=10	Amount of t, dk=10-2=8, α = 0,05	Determination
(R2)	
	rcount	rtable	tcount	ttable		
rx2y	0,749	0,632	3,193	1,86	
56,10%

The results of testing the second hypothesis obtained a correlation coefficient of rx2y = rcount 0.749> rtable 0.632 and tcount = 3.193> ttable = 1.86. Based on the testing criteria of the hypothesis that H0 is rejected Ha accepted, then in this study concluded that there is a positive and significant correlation between arm muscle power and the open smash ability results of male volleyball extracurricular athleteat Nurul Amaliyah vocational school Tanjung Morawa, North Sumatra. The determination coefficient of 56.10% explained that arm muscle power contributed 56.10% to the results of the ability of open volleyball smash.

3.	The correlation between Legs Muscle Power (X1) and Arms Muscle Power (X2) towards Open Smash Ability Results (Y) in Male Volleyball Extracurricular Athletes at Nurul Amaliyah vocational school Tanjung Morawa, North Sumatra.  

Table8. Correlation of coefficient X1 and X2with Y variable
Correlation	Correlation of coeficient, n=10	Amount of  F,dkpb:2  dkpy:10-2-1=7, 
α = 0,05	Determination
(R2)	
	rcount	rtable	Fcount	Ftable		
rx1y	0,822	0,632	7,301	4,74	
67,57%

The results of the third hypothesis test obtained a correlation coefficient of rx1x2y = rcount 0.822> rtable 0.632 and Fcount = 7.301> Ftable = 4.74. Based on the testing criteria of the hypothesis that H0 is rejected while Ha is accepted, then in this study concluded that there is a positive and significant correlationbetween leg muscle power and arm muscle power towards the open smash ability results of male volleyball extracurricular athleteat Nurul Amaliyah vocational school Tanjung Morawa, Sumatra Utara. The determination coefficient of 67.57% explained that leg muscle power and arm muscle power contributed 67.57% to the results of volleyball smash open ability while 32.43% was influenced by other variables.

DISCUSSION

Based on the results of this study, where the leg muscle power and arm muscle power contribute positively to the ability of open smash results,the corrrelation will be explained as follows:
1.	There is a positive and significant correlation between leg muscle power and the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra. Power of the limb muscles plays a role when jumping will do open smash by having good leg muscle power, it is useful to help the smasher produce high jumps and overcome the net height. It will make easier for the spiker to smash when floating in the air. The movement during the jump to reach the high net is an anaerobic movement that uses the ATP-PC energy system because of its explosive movements. In this case, Harsono (1988: 175) states that: To produce a strike in the smash is very determined with efficiency and the effectiveness of muscle movements which also involved, the leg muscles, among others (inferior extremity muscles), namely m. rectus femoris, m medial vascular, lateral mucus, m. biceps femoris, and m. gastronemius. As a support for repelling, it is clear that leg muscle power contributes positively to open smash.
2.	There is a positive and significant correlation between arm muscle power and the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra. Muscle explosive power is very important to do a motion activity in every sport. The explosive power of the arm muscles will determine how hard an athlete strike the ball, how far they throw or repul. The explosive power movement when hitting the ball is an anaerobic movement that uses the ATP-PC energy system because of its explosive movements. The explosive power of the arm muscles is influenced by the ability of the arm muscles, while the part of the arm muscles (superior extremity muscle) is m.trapezius, m. deltoideus, m.pectoralis major, m.biceps brachii, m.triceps brachii, m.brachialis, m.brachioradialis, m.pronator teres, m.flexor carpi radialis, m.flexor digitorum superficialis tendines. Power of the arm muscles is needed to produce punch strength in which the ball falls at high speed and dives sharply. it is clear that arm muscle power contributes positively to open smash.
3.	There is a positive and significant correlation between leg muscle power and arm muscle power towards the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra. Muscle explosive power is very important to do a motion activity in every sport. Power of the leg muscles is useful to help the smasher produce a high jump to overcome the height of the net so that it will make it easier for the smasher to smash when floating in the air while the arm muscle power is needed to produce punch strength so the ball falls at high speed and dives sharply. Because it is clearly proven that the smash requires several components, namely leg muscle power and arm muscle power. This shows that in the implementation of a smash between these two factors the leg muscle power and arm muscle power are inseparable and make a positive contribution.

CONCLUSION

	Regarding to the objectives of the study, it can be concluded that:
1.	There is a positive and significant correlation between leg muscle power and the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra with the results of the rx1y correlation of 0.822 and the tcount 4.086 with a significant level of 5%.
2.	There is a positive and significant correlation between arm muscle power and the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra. with the results of rx2y correlation of 0.749 and tcount of 3.193 with a significant level of 5%.
3.	There is a positive and significant correlation between leg muscle power and arm muscle power towards the open smash ability results in male volleyball extracurricular athletes at Nurul Amaliyah vocational school Tanjung Morawa North Sumatra with the results of rx12y correlation of 0.822 and F count 7.301 with a significant level of 5%. The determination coefficient of 67.57% explained that leg muscle power and arm muscle power contributed 67.57% to the results of volleyball smash open ability while 32.43% was influenced by other variables.

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