Effects of Isokinetic Shoulder Strength Training on Throwing Velocity in Collegiate Female Handball Players

ORİJİNAL ARAŞTIRMA Effects of Isokinetic Shoulder Strength Training on Throwing Velocity in Collegiate Female Handball Players Ahmet YILDIRIM, a Mehmet Settar KOÇAK, a Feza KORKUSUZ b a Department of Physical Education and Sports, Middle East Technical University, Faculty of Education, b Department of Orthopedics and Traumatology, Middle East Technical University, Medical Center, Ankara Ge liş Ta ri hi/re ce i ved: 21.03.2008 Ka bul Ta ri hi/ac cep ted: 16.09.2008 Ya zış ma Ad re si/cor res pon den ce: Ahmet YILDIRIM Middle East Technical University, Faculty of Education, Department of Physical Education and Sport, Ankara TÜRKİYE/TURKEY yahmet@metu.edu.tr ABS TRACT Objective : The purpose of this study was to examine the effects of isokinetic shoulder strength training on throwing velocity in collegiate female handball players. Material and Methods: Eleven healthy volunteer female collegiate handball players were assigned into experimental (n= 6) and control (n= 5) groups. Results: Testing and training for internal-external rotation (IR-ER) of the dominant and non-dominant shoulders were performed by using BIODEX isokinetic dynamometer. Both experimental and control groups were pre and post tested concentrically at 90-180 deg/s and eccentrically 90 deg/s and peak torque (PT) measures were recorded. Experimental group performed three concentric training in a week for four weeks at velocities of 90-120-180-120- 90 deg/s and 5-10-15-10-5 repetitions for both dominant and non-dominant shoulders. Three types of shooting style which were mostly used in handball were selected; 1) Three-step shot, 2) Jump shot and 3) Set shot on a spot. Maximum and average throwing velocities (Max-TV, Av-TV) were measured in km/h by a radar gun. four-weeks isokinetic strength training indicated significant differences for Av-TV for jump shot and eccentric PT-ER for non-dominant shoulder in pre and post tests of experimental group while the rest of the variables did not demonstrate significant difference. There was no significant difference in pre and post tests of control group. Conclusion: The addition of four-weeks of isokinetic strength training to the handball training resulted in gains only in Av-TV for jump shot and eccentric PT-ER for non-dominant shoulder but rest of the variables did not demonstrate significant difference. Key Words: Handball; isokinetic strength training; shoulder strength; throwing velocity ÖZET Amaç: Bu çalışmanın amacı üniversiteli kadın hentbol oyuncularında omuz bölgesine yönelik yapılan izokinetik kuvvet antrenmanının atış hızına etkisini araştırmaktır. Gereç ve Yöntemler: On bir sağlıklı kadın hentbol oyuncusu deney grubu (n= 6) ve kontrol grubu (n= 5) olarak ikiye ayrılmıştır. Bulgular: Dominant olan ve olmayan kollardaki internal ve eksternal rotasyon kuvvet testleri ve antrenmanları BIODEX izokinetik dinamometre kullanılarak yapılmıştır. Deney ve kontrol gruplarının ön testleri ve son testleri 90 ve 180 o /s konsantrik ve 90 o /s eksantrik olarak ölçülmüştür. Deney grubu dört hafta boyunca haftada üç gün 90-120-180-120-90 o /s hızlarda ve 5-10-15-10-5 tekrarlarda kuvvet antrenmanı yapmıştır. Hentbolde sıkça kullanılan dayanma adımı atışı, üç adımlı dayanma adımı atışı ve sıçrayarak atış türleri seçilmiştir. Radar gun kullanılarak atış hızları saptanmış ve her oyuncunun en yüksek atış hızı (Max-TV) ile ortalama atış hızı (Av-TV) kullanılmıştır. Sonuçlar dört hafta boyunca omuz bölgesine yönelik yapılan izokinetik kuvvet antrenmanının sıçrayarak atış hızının ortalamasını ve dominant olmayan koldaki ekzantrik eksternal rotasyon kuvvet değerinde anlamlı değişmeye sebep olduğunu gösterirken, diğer değişkenlerde anlamlı bir değişikliğe neden olmamıştır. Kontrol grubunda ise ön ve son testler arasında anlamlı bir fark gözlenmemiştir. Sonuç: Bu çalışmada hentbol antrenmanına ek olarak yapılan dört haftalık izokinetik kuvvet antrenmanının sadece sıçrayarak atıştaki ortalama atış hızında ve dominant olmayan koldaki ekzantrik eksternal rotasyon kuvvet değerinde anlamlı değişmeye neden olduğu, fakat diğer değişkenlerde anlamlı bir değişikliğe neden olmadığı gözlenmiştir. Anah tar Ke li me ler: Hentbol; izokinetik kuvvet antrenmanı; omuz kuvveti; atış hızı Cop yright 2009 by Tür ki ye Kli nik le ri Tur ki ye Kli nik le ri J Sports Sci 2009;1(1):11-6 Turkiye Klinikleri J Sports Sci 2009;1(1)Turkiye Klinikleri J Int Med Sci 2008, 4 11

Ahmet YILDIRIM ve ark. EFFECTS OF ISOKINETIC SHOULDER STRENGTH TRAINING ON THROWING VELOCITY... hro wing ve lo city and sho ul der strength are two im por tant con si de ra ti ons for hand ball. In hand ball, the ball sho uld be fast and ac cura te to the tar get for de si red per for man ce. Sud den and fast arm and sho ul der ac ti on with the cor rect tech ni qu e is very im por tant for sco ring a go al. In ju ri es in sho ul der jo int is very com mon in hand ball 1 and re ha bi li ta ti on is very im por tant for ath le tic per for man ce. 2,3 The na tu re of hand ball is open to com pe ti ti on and inc lu des many ac ti ons such as; dribb ling, pas sing, and thro wing. As handball is an over he ad thro wing sport as well as the body con tact sport, im por tan ce is pla ced on the sho ul der jo int and its strength and hen ce the ac cu - ra te as sess ment of sho ul der musc le per for man ce is im por tant for hand ball. Sho ul der musc le per for man ce can be as ses sed eit her by dyna mic or sta tic con trac ti ons. Iso ki ne - tic me a su re ment pro vi des qu an ti fi ca ti on of tor que, work, and po wer. 4 In ad di ti on, iso ki ne tic exer ci - ses pro vi de ma xi mal re sis tan ce thro ug ho ut the who le ran ge of mo ti on. Con cen tric and ec cen tric types of as sess ments are two dyna mic me a su re - ments and sho ul der in ter nal ro ta ti on (IR) and exter nal ro ta ti on (ER) are two es sen ti al mo ve ments for hand ball. In hand ball throw, in ter nal ro ta tor musc les (del to id, pec to ra lis ma jor, subs ca pu la ris, co ra cob - rac hi a lis, la tis si mus dor si, te res ma jor) act as fast as pos sib le to send the ball to the go al. At this ti me, ex ter nal ro ta tor musc les (sup ras pi na tus, in fras pi - na tus, del to id, te res mi nor) act re ac ti ve mo ve ment for de ce le ra ti on. Sta bi li za ti on bet we en in ter nal and ex ter nal ro ta tor musc les plays cru ci al ro le to pre vent in ju ri es du ring high ve lo city arm ac ti - on. 5-7 Tra i ners and sport the ra pists emp ha si ze injury pre ven ti on by iden tif ying we ak nes ses in strength and in bi la te ral and re cip ro cal musc le gro up strength re la ti ons hip. The ra ti o bet we en ago nist and an ta go nist musc le gro up is very im por - tant to avo id in ju ri es and show de si rab le per for man ces. 8-14 Pre vi o us stu di es in di ca ted that con cen tric isoki ne tic tor qu e du ring sho ul der ro ta ti on are sig ni fi - cantly re la ted to the thro wing ve lo city of a ba se ball. 15-17 Ho we ver, this re la ti on is not cle ar. Cle ments et al. 16 fo und that thro wing ve lo city is mo re re la ted with sho ul der in ter nal musc les than ex ter nal musc les. In con trast, Pe de ga na et al. 17 fo - und that thro wing ve lo city is mostly re la ted with sho ul der ex ter nal musc les. Mo re o ver, Ba yi os et al. 18 fo und no re la ti ons hip bet we en thro wing ve lo city in set shot and sho ul der in ter nal and ex ter nal ro ta - ti on. Wo o den et al. 19 sta ted that iso ki ne tic strength tra i ning has no ef fect on thro wing ve lo city and inter nal ro ta tor musc le strength. Stu di es re la ted with iso ki ne tic musc le strength for dif fe rent sport branc hes are well do cu men ted; ho we ver, the re are few stu di es abo ut hand ball. Hen ce the pur po se of this study was to exa mi ne the ef fects of iso ki ne tic sho ul der strength tra i ning on thro wing ve lo city in col le gi a te fe ma le hand ball pla yers. MATERIAL AND MET HODS SUB JECTS Ele ven he althy vo lun te er fe ma le col le gi a te handball pla yers, ages 18-23 (20.9 ± 1.7) par ti ci pa ted in this study. They we re as sig ned in to two gro ups randomly as: ex pe ri men tal gro up (n= 6; he ight: 169.8 ± 1.7 cm; we ight: 63.5 ± 5.2 kg; ye ars pla yed: 5.8 ± 1.8) and con trol gro up (n= 5; he ight:167.6 ± 1.8 cm; we ight: 58.6 ± 7.6 kg; ye ars pla yed: 6.2 ± 1.8). All sub jects we re in for med abo ut the na tu re and the pur po se of the study and in for med con sent was sig - ned by the sub jects. ISO KINE TIC SHO UL DER STRENGTH TEST Strength me a su re ments of do mi nant and non-do - mi nant sho ul ders we re tes ted con cen tri cally and ec cen tri cally at 90 deg/s and con cen tri cally at 180 deg/s be fo re and af ter the tra i ning pe ri od by using BI O DEX iso ki ne tic dyna mo me ter NY. Tes ting and tra i ning po si ti on for sho ul der in ter nal and ex ter nal ro ta ti on is shown in Fi gu re 1. Each par ti ci pant perfor med two sub ma xi mal and then fi ve ma xi mal con se cu ti ve con trac ti ons. Pla yers we re en co u ra ged to per form the ir best ef forts du ring the tests. Re li - a bi lity and va li dity of bi o dex dyna mo metry are pro vi ded with many stu di es. 16,20 12 Turkiye Klinikleri J Sports Sci 2009;1(1)

EFFECTS OF ISOKINETIC SHOULDER STRENGTH TRAINING ON THROWING VELOCITY... Ahmet YILDIRIM ve ark. of the 6-me ter li ne. Sub jects per for med fi ve throws for each style ran domly fol lo wed by a 10- min warm-up be fo re the test. The ma xi mum thro - wing ve lo city (max-tv) and ave ra ge of two hig hest thro wing ve lo ci ti es (Av-TV) we re re cor - ded. Sub jects we re en co u ra ged to throw the ball as fast as pos sib le. STA TIS TI CAL ANALY SIS Mul ti va ri a te analy sis of va ri an ces (MA NO VA) was used for pre test gro up com pa ri son and pa i red samp le t-test was used to exa mi ne dif fe ren ces bet we en iso ki ne tic strength and thro wing ve lo city for pre and post tests of two gro ups. Sta tis ti cal sig ni fi can - ce le vel was set at 0.05. FIGURE 1: Testing and training position for shoulder internal and external rotation. ISO KINE TIC STRENGTH TRA I NING Ex pe ri men tal gro up we re tra i ned thre e ti mes per we ek for fo ur we eks. All pla yers comp le ted twel ve tra i ning ses si ons (to tal 72). Pyra mi dal tra i ning at 90-120-180-120-90 deg/sec ve lo ci ti es and 5-10-15-10-5 re pe ti ti ons we re per for med for both do mi nant and non do mi nant sho ul ders. Four-six we eks pe ri - od are ade qu a te to test whet her the se lec ted strength tra i ning is ef fec ti ve. 19,21,22 But the se stu di - es we re con duc ted on se den tary pe op le and ba se - ball pla yers. A ma xi mal ef fort was per for med for all tri als to de ve lop ma xi mal strength. A thirty se - cond rest pe ri od was gi ven bet we en each set. THRO WING VE LO CITY ME A SU RE MENT Me a su re ments we re con duc ted on a stan dard si ze hand ball co urt and a go al, and ball spe ed was me - a su red in km/h by a ra dar gun, pla ced be hind the go al ac cor ding to the user ma nu al. Re li a bi lity and va li dity of the ra dar gun is cle ar with the pre vi o us stu di es. 15,17 Thre e types of thro wing style which we re mostly used in hand ball we re se lec ted. 18 The - se we re 1) Thre e-step shot, 2) Jump shot and 3) Set shot on a spot. All sho ots we re per for med in front RE SULTS The re was no sta tis ti cally sig ni fi cant dif fe ren ce bet we en ex pe ri men tal and con trol gro ups for the pre - test (Wilks = 0.046, F (9,1) = 2.29, p=.47). Pre and post re sults of me an ball ve lo ci ti es and SDs for thre e dif fe rent thro wing styles we re gi ven in Tab le 1 for ex pe ri men tal and con trol gro ups. Pa - i red samp le t-test re sults de mons tra ted that the re was a sig ni fi cant dif fe ren ces in Av-TV for jump shot (p<.05). The re sults in di ca ted that the me an con cern for post-test jump shot (Me an: 64.8, SD: 5.4) was sig ni fi cantly hig her than the me an concern for pre test jump shot (Me an: 60.8, SD: 7.6), t(5)= -3.2, p=.024. Ho we ver, the re was no sig ni fi - cant dif fe ren ce in Av-TV for 3-step shot and set shot in re la ti on to pre and post test re sults for expe ri men tal gro ups. In ad di ti on, max-tv was not sig ni fi cantly dif fe rent for the thre e thro wing styles for ex pe ri men tal gro up. Con trol gro up sho wed no sig ni fi cant dif fe ren ces bet we en pre and post-test re sults for Av-TV and max TV. Pre and post test re sults of me an strength me - a su res (ER, IR and con ven ti o nal ra ti o) and SDs for dif fe rent spe eds (con cen tric 90, con cen tric 180 and ec cen tric 90 deg/sec) we re gi ven in Tab le 2 for expe ri men tal and con trol gro ups. The re was no sig ni - fi cant dif fe ren ce in iso ki ne tic sho ul der strength me a su res and con ven ti o nal ra ti os for pre and posttest re sults for ex pe ri men tal and con trol gro up. In ex pe ri men tal gro up, the only dif fe ren ce was in ex- Turkiye Klinikleri J Sports Sci 2009;1(1)Turkiye Klinikleri J Int Med Sci 2008, 4 13

Ahmet YILDIRIM ve ark. EFFECTS OF ISOKINETIC SHOULDER STRENGTH TRAINING ON THROWING VELOCITY... TABLE 1: Throwing velocities for three different shooting styles. Pre-test Post-test Experimental Control Experimental Control Mean SD Mean SD Mean SD Mean SD Set shot on a spot Max-TV 57.2 7.3 58 6.1 59.8 3.4 58.6 4.3 Av-TV 56.6 6.9 56.1 6.1 59 3.3 58 4.5 3-step set shot Max-TV 59.8 2.8 60.8 7.3 60.5 4.1 59.6 7.1 Av-TV 58.8 3.3 59.4 7.1 60.1 4.1 59.4 7.2 Jump shot Max-TV 62.7 7.7 61.6 7.2 65.2 5.4 63 9.1 Av-TV 60.8 7.6 60.9 6.9 64.8* 5.4 61.7 8.6 * p<.05. TABLE 2: Pre and post-test PT and conventional ratio results for experimental and control group. Pre-test Post-test Dominant Non-dominant Dominant Non-dominant Mean SD Mean SD Mean SD Mean SD Control group Concentric 90 ER-PT 24.4 2.9 22.6 3.9 24.2 3.7 23.2 3.8 IR-PT 32.4 4.8 31.5 6.6 33.6 5.7 32.6 7.3 Ratio 0.76 0.06 0.72 0.05 0.73 0.07 0.72 0.06 Concentric 180 ER-PT 22 1.8 20.2 2.3 23.4 3.8 21.1 2.9 IR-PT 35.5 2.5 33.0 5.3 37.1 3.8 37 5.3 Ratio 0.62 0.05 0.62 0.04 0.63 0.08 0.58 0.06 Eccentric 90 ER-PT 47.7 8.3 46.9 8.4 48.4 5.4 49.4 6.8 IR-PT 31.5 6.0 36 7.8 37.3 12.1 35.5 11.2 Ratio 1.53 0.22 1.33 0.28 1.40 0.40 1.45 0.30 Experimental group Concentric 90 ER-PT 27.6 3.2 25.6 2.7 24.3 3.1 22.5 3.0 IR-PT 33.9 3.3 29.1 3.6 35.1 4.1 30.7 4.6 Ratio 0.82 0.05 0.88 0.05 0.69 0.09 0.74 0.1 Concentric 180 ER-PT 25.2 2.5 23.2 2.6 25.1 5.0 22.1 3.4 IR-PT 34.4 2.8 29 2.1 36.2 5.8 33.3 5.9 Ratio 0.73 0.07 0.81 0.12 0.69 0.07 0.67 0.1 Eccentric 90 ER-PT 45.7 5.4 41 5.9 49.7 3.6 46.8* 5.4 IR-PT 36.6 5.4 30.4 3.1 34.6 6.4 34.4 4.0 Ratio 1.26 0.16 1.35 0.22 1.47 0.2 1.36 0.1 *p<.05; PT= Peak torque; IR= Internal rotation; ER= External rotation. ter nal ro ta ti on-pe ak tor qu e (ER-PT) me a su re for non-do mi nant sho ul der. The re sults in di ca ted that the me an con cern for post test ER-PT (Me an= 46.8, SD= 5.4) was sig ni fi cantly gre a ter than the me an con cern for pre test ER-PT (Me an= 41, SD= 5.9), t(5)= -2.7, p=.044. Pre and post-test func ti o nal ra ti o re sults we re gi ven in Tab le 3. Func ti o nal ra ti os (Ecc ER/Con IR) 14 Turkiye Klinikleri J Sports Sci 2009;1(1)

EFFECTS OF ISOKINETIC SHOULDER STRENGTH TRAINING ON THROWING VELOCITY... Ahmet YILDIRIM ve ark. TABLE 3: Pre and post-test functional ratio results for experimental and control group. Pre-test Post-test Dominant Non-dominant Dominant Non-dominant Mean SD Mean SD Mean SD Mean SD Eccentric 90 ER/Concentric 90 IR Control group functional ratio 1.48 0.21 1.53 0.37 1.46 0.14 1.57 0.40 Experimental group functional ratio 1.35 0.17 1.43 0.30 1.42 0.08 1.54 0.19 for do mi nant and non- do mi nant sho ul ders we re ran ged bet we en the 1.35 and 1.57. DIS CUS SI ON The re sults sug gest that four we eks iso ki ne tic pyra - mi dal strength tra i ning was not very func ti o nal to im pro ve ball ve lo city. Max-TVs in thre e thro wing styles we re not sig ni fi cant and Av-TVs we re not sig ni fi cant for 3-step and set shot. The se re sults we - re con sis tent with the pre vi o us study in which they fo und iso ki ne tic strength tra i ning had no ef fect on thro wing ve lo city. 19 On the ot her hand, Mont et al. 23 sta ted that iso ki ne tic strength tra i ning had an 11% in cre a se in thro wing ve lo city. The pre sent study sus pec ted the in cre a se as the re was a slightly im pro ve ment in Av-TV for jump shot per for man - ce. Si mi larly, in a pre vi o us study, Fleck et al. 24 sta - ted that thro wing ve lo city of a te am hand ball jump shot de pends on mo re on up per ex tre mity strength than do es thro wing ve lo city of a te am hand ball set shot. Ba sed on the re sults of this study fo ur we eks iso ki ne tic pyra mi dal strength tra i ning was not very ef fec ti ve to im pro ve sho ul der strength. Pe ak tor qu - e IR and ER me a su res for con cen tric 90-180 and eccen tric 90 deg/sec ha ve not chan ged sig ni fi cantly for do mi nant and non-do mi nant sho ul ders ex cept the ec cen tric 90 deg/sec ER for non-do mi nant sho - ul der. Ho we ver, this im pro ve ment was qu i te small (p=.044). On the ot her hand, Mont et al. 23 fo und sig ni fi cant im pro ve ment in IR and ER strength for ex pe ri men tal gro up who se tra i ning con sis ted of 8 sets of 10 sub ma xi mal re pe ti ti ons for six we eks which in di ca te that hig her num ber of sets and re p- e ti ti ons re sul ted in im pro ve ment in IR and ER musc le strength. In anot her study Wo o den et al. 19 fo und that ER and IR of PT to body we ight (BW) me a su - res did not im pro ve sig ni fi cantly. In the ir study tra - i ning du ra ti on was fi ve we ek and the ir set num bers ha ve in cre a sed from 6 to 10 with ten re pe ti ti ons. Si - mi larly, Bast et al. 21 fo und no sig ni fi cant dif fe ren ce con cen tric IR and ec cen tric IR at the end of four we eks iso ki ne tic tra i ning for con cen tri cally tra i ned gro up. In ad di ti on to that, he sta ted that any tra i - ning re gard less of mo de can in cre a se the ec cen tric strength for ER. The non-do mi nant ec cen tric ER strength in cre a sed in the pre sent study. One of the ma jor re a sons for sho ul der in jury is strength im ba lan ce bet we en ago nist and an ta go nist musc les. The con ven ti o nal and func ti o nal ra ti os of pre sent study pro vi de prac ti cal da ta for sport the r- a pists. But the re was no study gi ving the strength ra ti os for fe ma le hand ball pla yers. Most of the stu - di es we re con duc ted on ba se ball pla yers and it is hard to com pa re the re sult of pre sent study. Go ros ti a ga and his col le a gu es 22 test the ef fects of six we eks of he avy re sis tan ce tra i ning on thro w- ing ve lo city. They fo und 3.2% in cre a se in thro wing ve lo city. Me an age of the ir sub jects was 15 and they we re ma le hand ball pla yers but the me an age in pre sent study was 21 and they we re col le gi a te fe ma le hand ball pla yers. So the age, gen der and expe ri en ce co uld inf lu en ce the tra i ning ef fects. In his re vi ew, van den Til la ar 25 exa mi ned the ef fect of diffe rent tra i ning prog rams on the ve lo city of over arm thro wing. He conc lu ded that the re was no cle - ar ans wer con cer ning the most ef fec ti ve tra i ning on thro wing ve lo city. This study has so me li mi ta ti ons such as; small samp le si ze and short du ra ti on of tra i ning. Fo ur we eks pe ri od pos sibly was not suf fi ci ent to show sig ni fi cant strength ga in. Lar ger samp le si ze with Turkiye Klinikleri J Sports Sci 2009;1(1)Turkiye Klinikleri J Int Med Sci 2008, 4 15

Ahmet YILDIRIM ve ark. EFFECTS OF ISOKINETIC SHOULDER STRENGTH TRAINING ON THROWING VELOCITY... va ri a bi lity in tra i ning de sign may help to find out mo re sig ni fi cant fin dings. Al so, sub jects of the study we re col le gi a te fe ma le hand ball pla yers and they we re not pro fes si o nal. So they had pri o rity to study les sons. Fin ding of this study co uld ha ve be - en af fec ted from pla yers in suf fi ci ent mo ti va ti on or con cen tra ti on du e to the exams. As a conc lu si on, four we eks con cen tric iso ki - ne tic tra i ning inc lu ding 5-10-15-10-5 re pe ti ti ons at 90-120-180-120-90 spe eds for do mi nant and non-do mi nant sho ul der was not very ef fec ti ve to im pro ve strength and thro wing ve lo city ex cept Av- TV for jump shot and ec cen tric PT-ER for non-do - mi nant sho ul der. 1. Dur maz B. Up per ex tre mi ti es in ju ri es in ath le - tes. Tur ki ye Kli nik le ri J Int Med Sci 2006;2(27): 18-28. 2. 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