CC BY
170Relationship between medicine ball explosive power tests, throwing ball velocity and jump performance in team handball players
Mourad Fathloun1, Souhail Hermassi2, Mohamed Souhail Chelly2, Abdelkrim Bensbaa3
1Research Unit, School and University Sportive Practices and Performance,
Higher Institute of Sport and Physical Education, Kef, Tunisia.
2Research Unit, Analysis and Evaluation of Factors Affecting the Sport Performance,
Higher Institute of Sport and Physical Education, Ksar Said, Tunisia.
3Military Centre of Physical Education and Sport (Abu Dhabi, United Arab Emirates).
Annotation:
In this study, the relationships between medicine ball explosive power tests, jump and handball throwing velocity performance in team handball players were investigated. Explosive test was measured by a medicine ball throw. Specific explosive strength was evaluated by making 3 types of overarm throw: standing position, using an adapted chair (without run-up, TW), a 3-step rnnnrng throw (T ) and a jump shot (JS). The jump test (SJ, CMJ and FCMJ) were determined using the OptoJump.
The medicine ball explosive power test was closely related to T3-Ste s. Significant relationships- were observed between medicine ball explosive power tests and (JS) and (TW). The Medicine balS explosive power test is also positively related to vertical jump ability represented by Squat Jump (SJ) and Countermovement Jump (CMJ). The results suggest an association of the medicine ball explosive power tests to performance in throwing events.
Keywords:
throwing, jumping, test, handball.
Фатхлун Мурад, Хермаси Сухаил, Щелли Мохамед Сухаил, Бенсбаа Абделкрим. Отношение между взрывной силой броска набивного мяч назад, скоростью мяча при броске и показателями вертикальных прыжков у гандболистов. В этой работе изучалось отношение между взрывной силой броска набивного мяч назад, вертикальными прыжками и скоростью мяча при броске у гандболистов. Оценка взрывной силы изучалась с помощью броска набивного мяча назад. Специальная взрывная сила броска в гандболе определялась измерением скорости мяча при 3х разных видах броска сверху: -сидя на адаптированном стуле, (без использования нижних конечностей и с фиксированным туловищем) (Т ); -в опорном положений после трёх шагов (■С ); -в прыжке ^у. Взрывная сила при прыгучести измерялась с помощью 3-х видов плиометрических прыжков ^, С1Ш и FCMJ) с использованием аппарата (OptoJump). Результаты исследования показали, что взрывная сила броска набивного мяча тесно связана с (Т^). Были замечены существенные отношения^ между взрывной силой броска набивного мяча ^1Б) и (Ти). Положительное отношение также определила взрывная сила броска набивного мяча к способности вертикальных прыжков, представленных ^) и (CMJ). Результаты свидетельствуют о том, что существует тесное взаимоотношение между оценкой взрывной силы броска набивного мяча назад с результативностью броска.
бросок, прыжки, тестирование, гандбол.
Фатхлун Мурад, Хермасі Сухаїл, Щеллі Мохамед Сухаїл, Бенсбаа Абделкрім. Відношення між вибуховою силою кидка набівного м'яч назад, швидкістю м'яча при кидку і показниками вертикальних стрибків у гандболістів. У цій роботі вивчалося відношення між вибуховою силою кидка набівного м'яч назад, вертикальними стрибками і швидкістю м'яча при кидку у гандболістів. Оцінка вибухової сили вивчалася за допомогою кидка набивного м'яча назад. Спеціальна вибухова сила кидка в гандболі, визначалася виміром швидкості м'яча при 3х різних видах кидка зверху: -сидячі на адаптованому стільці, (без використання нижніх кінцівок та з фіксованим тулубом) (Т ); - в опорному положенні після трьох шагів ІГ Р5); -у стрибці ^І3). Вибухова сила при стрибучості вимірювалася за допомогою 3-х видів пліометрічеських стрибків ^, СІШ і FCMJ) з використанням апарату (Ор^итр). Результати дослідження показали що, вибухова сила кидка набивного м'яча, тісно пов'язана з (ТЗ-БІерз). Були відмічені істотні стосунки між вибуховою силою кидка набивного м'яча, ^Ів) і (Т\м). Позитивне відношення також, визначила вибухова сила, кидка набивного м'яча, до здатності вертикальних стрибків, представлені ^) і (СШ). Результати свідчать про те, що існує тісне взаємовідношення між оцінкою вибухової сили кидка набивного м'яча назад, з результативністю кидка.
кидок, стрибки, тестування, гандбол.
Introduction.
Overhead throwing in individual and team sports is a complex body activity with sequential activation of body parts through the link system which, in a righthanded thrower, goes from the left foot to the right hand. Toyoshima and al. (26) have shown that 53.1% of the velocity of the overhand throws could be attributed to arm action, while the remaining 46.9% was due to the step and body rotation. From the acceleration phase of throwing, the arm is whipped from the position of extreme external rotation to one of internal rotation. Tullos and Erwin (27) have stated that an increased rotational range of motion of the shoulder may enable athletes who use overhead throwing to improve the efficiency of the internal rotator muscles and thus allow the ball to be delivered with faster velocity. Jobe and al (16, 17) and others (5, 10, 23) have meticulously investigated the strength and the range of motion of internal and external rotation in the pitching motion in baseball. It was found that, the pitcher is required to generate a large amount of torque in internal rotation to project the ball with sufficient velocity to be successful.
© Mourad Fathloun, Souhail Hermassi, Mohamed Souhail Chelly, Abdelkrim Bensbaa, 2011
In team handball, the ability to score a goal depends, in large part, upon the velocity of the ball and the accuracy of the throw. Thus, the exploration of the relationship between explosive test of throw and ball velocity is of paramount importance, since the existence of such a relationship, which is highly advantageous in sports involving throwing movements. The ball velocity and its relationship with isokinetic strength has been the subject of a number of studies directed mainly toward athletes and more specifically to baseball pitchers (4, 27). Pedegana and al. (24) tested isokinetically eight professional baseball players using a Cybex II Isokinetic Dynamometer to determine the relationship of upper extremity strength to throwing velocity. They reported a relationship between ball velocity and external rotation of the shoulder, but they didn’t show any relationship between ball velocity and internal rotation of the shoulder. Other researchers, however, have reported no relationship between ball velocity and isokinetic strength of the shoulders rotators (2, 4, 22) in baseball pitching. The discrepancy in the results may be due to certain factors such as the subjects’ characteristics and the isokinetic speed employed.
There is only one study which has examined the above relationship also in team handball throwing (11). Appar-
ently, the relationship between ball velocity and medicine ball explosive power tests has not been studied thoroughly in team handball.
The aim and methodology of the research.
The aim of our study was to examine the relationship between the medicine ball explosive power tests to jumping ability in team handball players with various throwing abilities, in three types of shot (on the spot, with a crossover step and with a vertical jump).
Nineteen male handball players (n=19) volunteered for the investigation (age: 21.37 ± 1.92 years; mass: 77.7 ± 9.67 kg; height: 1.83 ± 0.06 m and body mass index: 27.32 ± 5.85 kg.m2). Explosive test was measured by a medicine ball throw. Specific explosive strength was evaluated by making 3 types of overarm throw on an indoor handball court: standing position, using an adapted chair (without run-up TW), a 3-step running throw (T3-Steps) and a jump shot (JS). The characteristics (jump height) of the Squat Jump (SJ), the Countermovement Jump (CMJ) and the Free Countermovement Jump (FCMJ) were determined using the OptoJump measurement technology (Microgate, Bolzano, Italy).
Testing Procedures
On the first day of testing, the protocol was explained to the subjects, and they then watched a demonstration of the medicine ball throw. This was followed by a practice session. Subjects were given as many practice throws as they desired until they were able to make 3consecutive throws to within 0.50 m of their longest practice throw. This was followed by a rest period (typically 20 minutes) before completing the test protocol. Subjects performed their initial testing at least 5 days before their retesting, and all testing was conducted over a 21-day span. Testing consisted of a medicine ball throw that involved a movement pattern similar to that of a standard countermovement vertical jump. The medicine ball throws were performed using a 1.5 kg rubber medicine ball. For comparative purposes, subjects also completed a standard countermovement vertical jump. Before each session, the subjects performed their normal warm-up. They were also given several warm-up throws, followed by 3 measured trials in which they attempted to throw a medicine ball as far as possible. Each throw was measured for distance (meters), and eachjump was measured for height (meters). The subjects were also measured for their standing reach height (meters) and body weight (kilograms). Each trial was followed by approximately 45 seconds of passive rest before the subsequent trial. Testing was conducted so that each subject performed 3 medicine ball throws and 3 vertical jumps at each session. According to the test order, the subjects completed the jump trials first and the medicine ball throws second.
Squat Jump, Counter-movement Jump and Free Counter-movement Jump
The height of the vertical jumps was measured using the OptoJump measurement technology (Microgate, Bolzano, Italy). This measurement system is consistent and reliable (19) and uses optical sensors to measure the jump height on the basis of flight time, having the individual three tries. The best try was the used result.
Athletes performed the following vertical jumps: the squat jump (SJ) starting from a static semisquatting position (~90° of flexion) maintained for ~1 second and without any jump; the countermovement jump (CMJ) starting from a standing position, squatting preliminary movement, countermovement down and then extending the knee in one continuous movement for both jumps (SJ and CMJ) hands placed on the hips; the third jump was performed in a similar fashion to the countermovement jump except that the participant was instructed to perform it with arm help (free countermovement jump FCMJ). the subject was instructed to step with both feet into the OptoJump zone and execute the jump in such a way as to land as quickly as possible in a semi squat position (knee angle 90°) and then take off as fast and high as possible without swinging her arms In the phases of leaving the surface and landing on the ground, the knee and ankle joints had to be extended. The landing had to be on both feet (29). In each case, the height of jump was calculated by using the flight time.
Medicine ball explosive power tests:
The standing backward overhead medicine ball throw consisted of starting with the feet shoulder width apart, heels on the zero measurement line, and the medicine ball held with arms straight out front at shoulder height. The countermovement consisted of the subjects flexing the hips and knees. At the same time, they also flexed forward at the trunk, lowering the medicine ball to just below waist or hip height. After the countermovement, the subjects began to thrust the hips forward and to extend the knees and trunk. They flexed the shoulders, elevating the ball back up to shoulder height and beyond as they threw it back over their head. The arms were maintained in an extended manner. The finishing point was with the ankles plantar flexed; the knees, hips, and trunk extended; and the shoulders flexed to above the head. During the countermovement, the subjects were asked not to bend the knees or hips any more than they normally would for a standard countermovement vertical jump. The shoulders maintained at least 458 of shoulder flexion in relation to the trunk. At the end of the throw, the subjects’ feet were allowed to leave the ground, as would happen with a jumping motion, to minimize any deceleration component of the vertical ground reaction forces (Figure 1). The subjects were also asked to keep their arms as straight as possible as they threw the ball back over their head with a pendulum action. This instruction was meant to force the legs, trunk, and shoulders to generate the power, as would be the case in a vertical jump (3).
Handball throwing
The throwing test using an adapted chair was evaluated on an indoor handball court. One type of throw without run-up, (TR) was performed with one hand from a standing position, using an adapted chair. The trunk of the player was immobilized by a belt blocked; the shoulder was maintained in 90 degree of abduction and external rotation, and the elbow was flexed to 90 degrees. The test was undertaken after a 15-minute standardized warm up and using a standard handball (mass 480 g, circumference 0.58 m). To simulate a typical handball action, the players
were allowed to put resin on their hands and they were told to throw with maximal velocity towards the upper right corner of the goal. The coaches supervised both tests closely to ensure that the required techniques were followed. Each subject continued until three correct throws had been recorded, up to a maximum of three sets of three consecutive throws. A 1- to 2-minute rest was allowed between sets of throws and 10-15 seconds between two throws of the same set. The 3-step running throw (T3-Steps) have been described by Hermassi and al (15). In the jump shot (JS), players made a preparatory three step run before jumping vertically and releasing the ball while in the air, behind a line 9m from the goal.
All the throwing times were recorded by digital video camera (Sony Handycam DCR-PC105E, Japan), positioned on a tripod 3 m above and parallel to the player. Data processing software (Regavi & Regressi, Micrelec, Coulommiers, France) converted measures of ball displacement to velocities. Throws with the greatest starting velocity were selected for further analysis. The reliability of the data processing software has been verified previously (7); measurements were accurate to 0.001 s, and the test-retest coefficient of variations in throwing velocity was 1.9%.
Statistical analysis
Variables are expressed as mean ± standard deviation (m ± SD). Pearson product-moment correlations tested relationships between medicine ball explosive power tests, jump performance and throwing tests and. P<0.05 was taken as the limit of significance in all statistical tests. The reliability of the throwing ball modes, jumping ability and medicine bal throw measurements was assessed using Intraclass Correlation Coefficients (ICC) (25). An ICC over 0.90 is considered as high, 0.80-0.90 is moderate and values below 0.80 indicate that a physiological field test is inadequate (28).
Analysis and discussion of research results.
The Intraclass correlation coefficients for all parameters of reliability were in the table 2. The mean and standard deviation of all values of medicine ball explosive power tests, jump abilities and throwing ball velocity for each group are presented in table 1. The relationship between medicine ball explosive power tests and ball velocity was, in general, was statistically significant for all speeds of throw, types of throw and groups tested.
T3-Step is closely related to the medicine ball explosive power tests (r = 0.68, p<0.01 for both relationships, Table 3). Moreover, the jump shot is moderately related to medicine ball test (r = 0.50, p<0.05) (Table 3), (Figure 2). The throwing test using an adapted chair (without run-up, TW) is also very large related to medicine ball explosive power tests (r = 0.61, p<0.05; r = 0.62, p<0.05 respectively), (Table 3) and (Figure 2).
The medicine ball explosive power tests is closely related to SJ tests (r = 0.60, p<0.01 for both relationships), (Table 3) and (Figure 3). Moreover, the CMJ is moderately related to medicine ball test (r = 0.48, p<0.05) (Table 3) and (Figure 3). The only exceptions were for the CMJ Free not associated with medicine ball test (R=0.17, p=0.029).
Our main purpose was to examine relationships between medicine ball explosive power tests and throwing ball velocity at different jump shot. The hypothesis that both upper and lower limbs contributed to throwing performance, was confirmed. T3-Step was closely related to medicine ball test (r = 0.69, p<0.01 for both relationships) and it also showed moderately strong relationships to jumping ability (r = 0.56, p<0.05; r = 0.62, p<0.05 respectively). This seems the first investigation to demonstrate the substantial contribution of the lower limb muscles to the throwing velocity of handball players.
The main finding in our study was that, generally in handball, in three types of throw with various throwing abilities, and jumping performance was related to ball velocity. When comparing our findings with the results of Fleck’s and al. (11) study conducted in handball players of the U.S. National Team, we observe both agreements and disagreements. Fleck et al. (11) did not find a significant relationship between the ball velocity in set shot and shoulder rotation at any of the isokinetic speeds studied (180, 240 and 300 deg/sec), which is in agreement with our results regarding the shot on the spot (same as set shot). However, they found a significant correlation between concentric rotation and jump shot at all speed tested.
Hawley and al (14) found a correlation coefficient of 0.63 between the peak power of the upper limbs as evaluated by the Wingate test and the speed of a 50-m swimming sprint. In their study, the ratio of upper limb peak power to lower limb peak power was 45%. These results seem in accordance with our present study; we found a correlation of 0.69 between explosive medicine ball test and T3-Step (Table 3, Figure 1).
Several recent studies of elite male handball players (8, 12, 13, 18) investigated the relationships of throwing velocity to bar velocity and bar power during bench press or half squat. Gorostiaga EM et al. (12) reported a close relationship between 3-step running velocity and the bar velocity at 30% of 1-RMBp (r = 0.72, p<0.01), with a moderate relationship to power at 100% of body mass in the half squat exercise (r = 0.62, p<0.05). A close relationship between standing throwing velocity and 1-RMBp (r = 0.80, p<0.001) was also reported (8, 9).
Moreover, throwing velocities showed moderate relationships with the bench press bar velocity and the power achieved at 38%, 52% and 52%, 67% of body mass respectively (18). Nevertheless, it is difficult to compare these results with our findings, because of differences in methodology and the type of ergometer that was used. The studies cited used a rotary encoder linked to the end of the bar to record bar displacement, average velocity and average power of the bar. Moreover all of these parameters were only assessed during a concentric bench press exercise. In our investigation, we measured explosive power as dependent variables. In addition, we adopted a simultaneous eccentric-concentric upper limb muscle contraction with medicine ball throw.
To our knowledge, the relationships of medicine ball explosive power tests, throwing ball velocity as measured with a simultaneous eccentric-concentric contraction have
Results of all parameters measurements (n = 19).
Table 1
Mean ± SD
Medicine ball explosive power tests (m) 15,35 2,34
Ball-throwing velocities (ms-1)
Throwing test using an adapted chair (TW) 20,97 4,59
3-Step running throw (T3-Steps) 32,43 8,30
Jumping shot (JS) 35,18 11,22
Jump tests (cm)
Squat Jump (SJ) 35 5,38
Counter Movement Jump (CMJ) 45,60 4,58
Free Counter Movement Jump (FCMJ) 43,22 6,62
Table 2
Intraclass correlation coefficients showing the reliability of various measures of ball-throwing velocities, and jump tests
ICC 90% CI
Ball-throwing velocities
Throwing test using an adapted chair (TW) 0.96 0.91 to 0.97
3-Step running throw (T3-Steps) 0.97 0.92 to 0.98
Jumping shot (JS) 0.94 0.95 to 0.98
Jump tests
Squat Jump (SJ) 0.95 0.93 to 0.98
Counter Movement Jump (CMJ) 0.93 0.91 to 0.96
Free Counter Movement Jump(FCMJ) 0.97 0.93 to 0.98
Table 3
Correlation between medicine ball explosive power tests to jumping ability in team handball players with various throwing abilities
T W T 3-Steps JS
Medicine ball explosive power tests R =0.61, p<0.01 R =0.68, p<0.01 R= 0.50, p<0.05
SJ CMJ CMJ Free
R =0.60, p<0.01 R =0.48, p<0.05 R =0 .17 no sig
not been described previously. Moreover, the medicine ball test, although rarely measured in handball studies, is rather specific to the action of handball throwing. Our results suggest that the simple measurements of explosive ball throw and jump performance could be useful tools for the handball coach, since these two exercises are often used in resistance strength training programs. Regular use of bench press and pull-over exercises could form an important component of a resistance training program designed to increase the throwing velocity of handball players. This suggestion merits the testing by further prospective research. This observation challenges the conclusion
of Fleck et al. (11) that the ball velocity of a team handball jump shot depends more on upper extremity torque capabilities than doe’s ball velocity of a team handball set shot, even though the two tasks are similar.
A possible explanation for finding a significant relationship between shoulder rotators isokinetic strength and ball velocity only in jump shot and not during the shots with ground support (set shot in both Fleck’s et al. and the present study; cross over step in the present study) (11) is the following: During the set shot and the shot with a cross-over step, the feet are in contact with the floor, making it possible for the lower-extremity strength and trunk
rotation to increase ball velocity by using the ground reaction forces. During the throwing motion of a jump shot, on the other hand, the player is in the air, making it difficult to use lower-extremity strength and trunk rotation to increase ball velocity during the throw.
In the study of Fleck’s et al. (11) the throwing motion in handball was examined with high-speed, two-plane, synchronized camera. It was observed that set shot throwing in handball is quite similar to baseball pitching and same differences in the throwing movement between the two sports are due to ball size and weight. This observation allows us to compare our results from team handball with those obtained in baseball.
The lack of a relationship between the strength of shoulder rotators and the ball velocity implies that the internal and external rotation is not the sole determinant factor in throwing movement in handball. Since throwing is a multipoint action, a variety of factors may contribute to this movement. Indeed, Atwater (1) and Toyoshima et al. (26) have shown throwing to be a complex motion involving all body parts. It has been suggested by Toyoshima that approximately 50 percent of throwing velocity is the result of body rotation, while the remainder is the result of upper-extremity action. Further, Pappas et al. (23) have described the anatomical sequence of throwing as proceeding from the fixed foot, up through the pelvis and
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Figure 2: Relationship between 3-step running handball throwing, jump shot and medicine
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Figure 3: Relationship Counter movement jump, squat jump and medicine ball explosive power test.
trunk, to the upper extremity. Sequential rotation of each body segment generates torque which applies force to the ball. Therefore, the importance of the lower extremity movement and trunk rotation should not be minimized when examining throwing movements.
Summary and conclusions.
Several conclusions can be drawn from this investigation regarding team handball players: Peak torque of upper limb shoulder rotators, generally is related to ball velocity. The lack of relationship between ball velocity and peak torque of internal and external shoulder rotators is more marked and consistent in shots with ground support (on the spot, with a cross over step). In jump shots, the isokinetic strength of upper extremities seems to be, to some extent, related to ball velocity, but this relationship in not very clear and needs further investigation. Ball velocity is different among players with various throwing abilities in the three basic types of throw in handball (on the spot, with a cross-over step, with a vertical jump). Our results also highlight the contribution of both the lower and the upper limbs to handball throwing velocity, suggesting the need for coaches to include upper and lower limb strength and power programs when improving the throwing velocity of handball players.
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Came to edition 17.02.2011.
Mourad Fathloun Souhail Hermassi Mohamed Souhail Chelly mfadhloun@yahoo.fr Abdelkrim Bensbaa levion2001@yahoo.fr
