Marko, M. et al.: Biomecanical analysis of extraleague players shooting in Eurovia Sport Science 8 (2015) 2: 52 56

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1 BIOMECHANICAL ANALYSIS OF EXTRALEAGUE PLAYERS SHOOTING IN EUROVIA SLOVAK BASKETBALL LEAGUE Michal Marko, Elena Bendíková and Robert Rozim Faculty of Arts, Matej Bel University, Slovak Republic Original scientific paper Abstract The study presents causative biomechanical analysis of motion of EUROVIA basketball league players in Slovakia, who completed ten three-point field shooting attempts recorded by high-speed camera from the right side of a shooting player. The biggest visible changes have occurred in angular changes at elbow and knee joint and in speed of radial-wrist and elbow joint, which directly determined the elevation angle of the shooting. These findings declare the importance of the longer distance shooting in relation to the victory in basketball game. Key words: basketball shooting, biomechanical analysis of the motion, joint changes Introduction Basketball shooting is in the basketball classification classified among offensive basic fundamentals (Velenský, 2008). Mačura (2010), Argaj, Rehák (2007), Krause et al. (2008), Tománek (2010) characterize basketball shooting as challenging motion activity of the player, whose main objective is to place the ball in the hoop, so it goes top-down through the hoop. Ďuračka (2011) also adds that basketball shooting is unlike other sport games the activity challenging for the muscular sense, distance estimation, subtle differentiation of the fingers, hands and arms movement. Force component is not primary, even though it has got its foundation, especially in the longer distance shooting (Trnovský et al., 1992). Basketball shooting classification is systematic arrangement and sorting of shooting into group according to declaratory characters but we still meet with diametrically opposed values, especially in the shorter and middle distance shooting (Mačura, 2010). Table 1 Length of the shooting from longer distances according to different authors Hermann (1957, s.32) Dobrý (1965, s. 48) Dobrý (1980, s. 66) Distance [m] large/long Riecky et al. (1982, s. 55) Distance [m] large/long Jetleb et al. (1982, s. 71) Dobrý et al. more than (1987, s. 69) 6,25 Table 2 Values of elevation angle and velocity of the ball according to different authors Hartley (1971, s ) Hay (1978, s ) Brancazio (1981, s ) Knudson (2007, s. 236) Elevation angle [ ] Brancazio (1981, s ) Hamilton (1997, s ) Satern (1993, s. 20) Tran (2008, s ) Velocity of the ball [m/s] 6,0-6,3 7,3 6 6 s are united in the case of longer distance shooting and they report almost identical distances (table 1). The longer distance shooting is considered to be the most important shooting action with which we meet in basketball (Hess, 1980). Proof of this statement can be found in the toughest and most attractive basketball league on "the Old Continent" - Spanish League ACB (Asociación Clubs Baloncesto), where the total number of achieved points in basketball game from the longer distance represents 41 %. In Slovak Basketball League (SBL) similar numbers have been recorded as well as in the Spanish League. Up to 52 % of the total points have been achieved by shooting from longer distances and 33 % of the total points have been scored from the three-point line. Among the most important factors, that influence percentage of shooting from longer distances, include elevation angle and velocity of the ball travelling in a parabolic curve (table 2). The higher the ballistic curve is, the greater probability is that the ball enters the hoop. The height of ballistic curve depends on the strength of the player, especially on the strength of upper limbs. Aim The aim of the study has been biomechanical analysis of shooting from longer distances within selected extraleague players in Slovak basketball league EUROVIA in relation to victory in basketball game. Methods The monitored group has consisted of three extraleague players of basketball club EUCOS Levickí Patrioti, which plays in the Slovak basketball league EUROVIA SBL. The primary characteristic of the monitored group presents table 3. We conducted monitoring on the 01/30/2015 in Levice sports hall. The players shot ten attempts from the three-point line (6,75 m, 22,1 ft) while they were using officially approved basketball (Spalding TF- 100 SBA Legacy) hoop and lines, which have been 52

2 approved by FIBA regulations. All of the players have had dominant right hand, player no. 2 and no. 3 have specialized in basketball shooting from medium and longer distances and basketball player no. 1 has been playing on position called "power forward". To record shooting from longer distances we were using high-speed camera PCO 1200 hs, which was located by the players right side at the distance of 14 meters and at the height of 1,85 meters. The camera was set up to record 500 images per second, while the exposure time represented value of 0,005. Camera recording was set up at the resolution of 760 x 1024 with value of the screen 2. On each body of the players there were signs placed, on the right upper limb (radialwrist joint, elbow joint and shoulder joint) and on the right lower limb (hip joint, knee joint and ankle joint). While inserting white signs we determined the middle of the basketball by using method called "triangulation", in which we used the coordinates of the three points and defined a perimeter of the ball. According to signs placed, we calculated angular changes of the joints after releasing the ball, angular velocity of the joints before releasing the ball, velocity of the joints due to releasing the ball, height and distance of jump during shooting. While interpreting results of shooting from longer distances among selected extraleague players we used method of observation and casuistry by using logical analysis while analyzing data and information from recorded video and synthesis in forming conclusions, as well as arithmetic mean (±) and analysis of percentage frequency (%) through which we expressed determined data and facts into tables and graphs. Results Table 3 Characteristic of monitored group of basketball players EUCOS Levickí Patrioti Monitored group Nationality Date of birth Decimal age Length of practice Weight Height [kg] [cm] Slovak , Serbian , American , Table 4 Evaluation of angular changes of the joints after releasing the ball SHOOTING S. Ch. Radial-wrist Elbow Shoulder Hip Knee Ankle Max Min Diff Max Unsuccessful Min Diff Max Min Diff Max Unsuccessful Min Diff Max Min Diff Max Unsuccessful Min Diff Table 5 Evaluation of angular velocity of the joints before releasing the ball SHOOTING S. Ch. Radial-wrist Elbow Shoulder Hip Knee Ankle Max. 1501, ,21 721,88 477,62 553,09 751,56 Min. 141,34 482,48 255,51 120,80 226,91 173,00 Diff. 1360,00 560,73 421,37 356,82 326,18 578,56 Max. 1382,79 853,21 658,92 431,21 521,49 732,64 Unsuccessful Min. 211,92 428,59 231,42 110,29 208,99 158,09 Diff. 1170,87 424,62 427,50 320,92 312,50 574,55 Max. 1486, ,21 731,41 475,21 572,35 762,62 Min. 193,21 472,51 267,49 149,21 251,32 183,21 Diff. 1293,08 651,70 463,92 326,00 321,03 579,41 Max. 1398,12 882,07 628,93 422,31 525,85 721,34 Unsuccessful Min. 211,92 432,43 221,68 123,51 221,51 159,28 Diff. 1186,20 449,64 407,25 298,80 304,34 562,06 Max. 1241,48 825,88 603,79 406,75 614,98 775,94 Min. 114,08 352,93 176,81 137,94 214,40 132,99 Diff. 1127,40 472,95 426,98 268,81 398,58 640,95 Max. 972,61 672,42 491,74 315,20 980,77 529,26 Unsuccessful Min. 369,72 368,91 217,16 95,71 143,95 135,10 Diff. 602,89 303,51 274,58 219,49 836,82 394,16 53

3 Table 6 Evaluation of velocity of the joints in consideration of releasing the ball SHOOTING S. Ch. Radialwrist Elbow Shoulder Hip Knee Ankle Max. 0,125 0,043 0,067 0,131 0,134 0,138 Min. -0,315-0,152-0,339-0,281-0,279-0,251 Diff. 0,440 0,195 0,406 0,412 0,413 0,389 Max. 0,144 0,144 0,079 0,149 0,139 0,142 Unsuccessful Min. -0,329-0,171-0,345-0,300-0,289-0,269 Diff. 0,473 0,229 0,424 0,449 0,428 0,411 Max. 0,129 0,049 0,064 0,135 0,139 0,137 Min. -0,319-0,158-0,338-0,285-0,279-0,255 Diff. 0,448 0,207 0,399 0,420 0,418 0,392 Max. 0,146 0,055 0,077 0,145 0,147 0,142 Unsuccessful Min. -0,328-0,175-0,342-0,292-0,287-0,327 Diff. 0,474 0,230 0,419 0,437 0,434 0,407 Max. 0,144 0,052 0,078 0,144 0,144 0,144 Min. -0,310-0,150-0,343-0,277-0,277-0,243 Diff. 0,454 0,202 0,421 0,421 0,421 0,387 Max. 0,167 0,067 0,089 0,152 0,152 0,152 Unsuccessful Min. -0,320-0,167-0,333-0,298-0,267-0,264 Diff. 0,487 0,234 0,422 0,450 0,419 0,416 The study presents partial results in relation to objective, which is subject to further exact processing and monitoring. In table 4 we present measured angular changes of the joints after releasing the ball from longer distances, where we found out that the greatest differences in angular changes of the joints after releasing the ball were in elbow joint, where the difference between successful and unsuccessful shooting from longer distances were in a ratio of 86,3 : 65,6, thus each player during unsuccessful shooting diverted from ideal angular change in the elbow joint of 20,7. Furthermore, we found out that two players (player no. 2 and player no. 3) had high angular differences of knee joint, which caused excessively high horizontal and vertical jump. Among the same two players we recorded significant angular differences of the ankle joint. Ankle joint was during unsuccessful shooting affecting knee joint, which lead to wrong angular change and consequently led to unreasonable high horizontal and vertical jump during shooting and faster releasing the ball. We did not find out any significant differences of the successful and unsuccessful shooting from longer distances among player no. 1 of his knee and ankle joints, although we observed significant differences in measurements of angular changes of the hip joint at ratio of 48 : 36. The mentioned player did not have optimal angle of the hip joint during shooting (179 ), therefore during shooting from the threepoint line was unsuccessful. The above findings show that the angular changes of the elbow joint of the right upper limb, as well as ankle joint and knee joint after releasing the ball were the main determinants of determining successful shooting from longer distances. The second monitored indicator was angular velocity of the joints before releasing the ball (table 5). Obtained information from successful and unsuccessful shooting from longer distances showed that the greatest angular velocity of the joints before releasing the ball was in radial-wrist joint and elbow joint. The biggest differences in successful and unsuccessful shooting in angular velocity of the joints before releasing the ball were measured among player no. 3, where ratio of successful and unsuccessful shooting was 1127,40 /s : 602,89 /s. Due to high difference in the angular velocity of radial-wrist joint caused fast, intense and untimely shooting. The player no. 3 was recorded with the difference in measurements in the angular velocity of knee joint, while during unsuccessful shooting was the angular velocity higher about 438,24 /s. The angular velocity of the ankle joint during unsuccessful shooting was significantly decreased by 264,79 /s, therefore the player no. 3 tried to compensate it by increasing the angular velocity of the knee joint. Among the players no. 1 and no. 2 were the most visible changes of the angular velocities of the radial-wrist joint and in elbow joint. Due to incorrect movement of radial- wrist joint the mentioned players got into unfavorable position towards the basketball hoop, which resulted into unsuccessful shooting from longer distances. The obtained results (velocity of the joints in consideration of releasing the ball) about shooting from longer distances are presented in table 6. Among all of the players who were shooting from longer distances was the ratio between successful and unsuccessful shooting in all joints of upper limb, as well as in joints of lower limb ranged from 0,1s to 0,3s. The biggest values of velocity of the joints in consideration of releasing the ball were measured in radial-wrist joint, which determined velocity of the ball after releasing the ball as well as elevation angle. On the contrary, the smallest values were measured in elbow joint, where its maximum and minimum velocity of successful and unsuccessful shooting reached within one tenth of a second, respectively two hundredths of a second. The height and distance of jump during shooting from longer distance play an important role in basketball. Among all of the players we measured growing tendency of vertical and horizontal jump during unsuccessful shooting (figure 1). Changing of the vertical and horizontal jump caused that the player during shooting did not get into ideal height, which resulted into successful, respectively unsuccessful shooting from longer distances in basketball. 54

4 Among player no. 3, we measured his horizontal jump with the difference between successful and unsuccessful shooting only with 1,11 centimeters, which pointed out the fact that the dominant determinant of successful shooting for the player no. 3 was height of vertical jump. In addition to vertical jump among player no. 3, the height and distance of jump during shooting was significantly changing among all of the players, which resulted in inefficiency of shooting. For acceleration and constant velocity of the ball is well-known fact: "the more slowly ball travels along a ballistic curve to the hoop, the greater probability of success of shooting from longer distances in basketball is". The figure 3 presents elevation angle of shooting from longer distances, which did not have increasing tendency as previous two determinants, although these determinants are determining of successful shooting in basketball. All of the players had a common decreasing tendency of elevation angle of shooting from longer distances in unsuccessful shooting. Scale of the elevation angle depends on the strength of a player, especially on the strength of the upper limbs, although among all of the players player no. 3, who has been playing at the basketball position called "power forward", was shooting below the smallest elevation angle 57. Figure 1 Height and distance of jump during shooting from longer distances The figure 2 presents velocity of the ball after releasing it from the hand, which had among all of the players increasing tendency as well as height and distance jump of shooting. This phenomenon resulted in unsuccessful shooting from longer distances in basketball. Figure 3 Elevation angle of shooting from longer distances Conclusion Figure 2 Velocity of the ball after releasing it from the shooting hand The results indicate that the most visible changes occurred in angular changes of the elbow and knee joint and at the velocity of the radial-wrist and elbow joint, which directly determines elevation angle of shooting. Visible changes also occurred at the velocity of joints in consideration of releasing the ball, height and distance of jump during shooting, velocity of the ball after releasing it from hand and elevation angle. The above findings highlight the importance of shooting from longer distances in relation to victory in basketball game. References Argaj, G., & Rehák, M. (2007). Teória a didaktika basketbalu II. Bratislava: Univerzita Komenského, 137p. Brancazio, P.J. (1981). Physics of Basketball. American Journal of Physics. 49(1), Dobrý, L. (1965). Košíková mládeže. Praha: STN, 224p. Dobrý, L., et al. (1980). Košíková. Praha: SPN, 303p. Dobrý, L., et al. (1987). Košíková. Praha: SPN, 303p. Ďuračka, Ľ. (2011). Didaktika basketbalu a návody na cvičenia. BA: STU, 77p. Hamilton, G.R., et al. (1997). Optimal Trajectory for the Basketball Free Throw. Journal of Sport Sciences, 15(5), Hartley, J.W., et al. (1971). Mechanical Analysis of the Jump Shot. Athletic Journal, 51(5), Hay, J.G. (1994). The Biomechanics of Sports Techniques. Physical Educator. 38(5), Herrmann, G. (1957). Basketbal. Bratislava: SPN, 94p. Hess, C. (1980). Analysis of the Jump Shot. Athletic Journal, 61(3), Jetleb, J., et al. (1982). Basketbal. Praha: Olympia, 169p. Knudson, D. (2007). Fundamentals of Biomechanics. Chico: California State University, 319p. 55

5 Mačura, P. (2010). Biomechanika basketbalovej streľby. Bratislava: UK, 240p. Riecky, A., et al. (1982). Basketbal, učebné texty pre školenie trénerov III. triedy. Bratislava: Šport, 178p. Satern, M.N. (1993). Kinematic Parameters of Basketball Jump Shots from Varying Distances. International Symposium on Biomechanics in Sport, 1(1), 20. Velenský, M. (1999). Basketbal. Praha: Grada publishing, 104p. Krause, J., et al. (2008). Basketball skills and drills. USA: Human Kinetics, 254p. Tománek, Ľ. (2010). Teória a didaktika basketbalu. Bratislava: ICM agency, 221p. Tran, C.M., et al. (2008). Optimal Release Conditions for the Free Throw in Men s Basketball. Journal of Sport Sciences, 26(11), Trnovský, I., et al. (1992). Teória a didaktika športovej špecializácie basketbal. Bratislava: UK, 174p. BIOMEHANIČKA ANALIZA ŠUTIRANJA KOŠARKAŠA U EUROVIA SLOVAČKOJ KOŠARKAŠKOJ LIGI Sažetak Studija predstavlja uzročnu biomehaničku analizu kretanja igrača EUROVIA košarkaške ligu u Slovačkoj, koji su završili deset pokušaja snimanja u polje s tri točke zabilježeno kamerom velike brzine s desne strane u trenutku šutiranja igrača. Dogodile su se najveće vidljive promjene u kutnim promjenama na lakatnom i zglobu koljena i na brzini radijalnog-zgloba i lakta, što izravno određuje kut elevacije šuta. Ovi rezultati pokazuju važnost analize šuta s većih udaljenosti u odnosu na pobjedu u košarkaškoj igri. Ključne riječi: košarkaško šutiranje, biomehanička analiza gibanja, promjene u zglobovima Received: October 24, 2015 Accepted: December 5, 2015 Correspondence to: Michal Marko Matej Bel University, Faculty of Arts Department of Physical Education and Sports Banská Bystrica, Tajovského 40, Slovakia Phone: , michalmarkojv@gmail.com This project was supported by VEGA 1/0376/14. 56