The Relation between Performance Values with Different Characteristics and Hematological Results of Professional Soccer Players.

Transcription

1 The Relation between Pefomance Values with Diffeent Chaacteistics and Hematological Results of Pofessional Socce Playes Alpe Kaadağ School of Physical Education and Spot, Adahan, Tukey Abstact: Pupose: Socce which is the most popula spots in the wold equies vaious factos such as technical/biomechanical, tactical, mental and physiological aspects fo success. In this study, the elations between the esults of pefomance tests coming fom diffeent enegy tansfe systems depending on intensity and time and hematological esults occu in a socce game of 90 minutes wee investigated. Methods: 24 socce playes with age of 22.2 ± 2.0 yeas, height of 77.0 ± 4.7 cm and body mass of 7.9 ± 6.4 kg joined this study. Afte measuing the hematological esults of the subjets the loss (decease) in thei maximal aeobic (20 m shuttle un test), anaeobic (wingate test) capacities, spint ability (30 m) and epeated spint (6 x 30 m spint) pefomances wee detemined. Results: Afte the findings wee evaluated, it was detemined that the elation between maximal oxygen consumption (VO2max) and mean powe is 0.0 and elation between VO2max and pecentage decement in epeated spint ability is 0.05, the elation between peak powe and fastest spint value is 0.0, the elation among each hematological values was 0.0. Conclusion: The fuel equied in socce game fo motions pefomed with o without ball is supplied by diffeent enegy systems depending on intensity and time. These enegy systems ae in an inteaction in diffeent levels among themselves independent fom hematological values. [Kaadağ A. The Relation between Pefomance Values with Diffeent Chaacteistics and Hematological Results of Pofessional Socce Playes. Life Sci J 203;0(5s): ] (ISSN: ).. 65 Key Wods: Maximal Oxygen Uptake, Anaeobic Powe and Capacity, Spint Powe, Pecentage Decement, Hematological Values, Socce Playes. Intoduction Socce pefomance depends on vaious factos such as technical-biomechanical, tactical, mental and physiological aspects (Stølen et al., 2005). Physiological demands equie the playes to be sufficient in vaious aeas such as aeobic and anaeobic powe, muscle stength, elasticity and agility. In socce game consisting of execise peiods of high intensity intespesed among execise peiods of low intensity the enegy equied (Svensson & Dust, 2005) is supplied both by aeobic and anaeobic metabolism (Foss & Keteyian, 998; Bompa, 999; Guyton & John, 20). The enegy systems do not activate sepaately one by one manne but in a scolling manne depending the time and intensity chaacteistics of the activity (Åstand & Rodahl, 986; McAdle, 2000). Thee is a need fo enegy fo the fomation of body movements and muscle contactions. This need is fulfilled by the enegy that aouses afte degading the last bond in the adenosine tiphosphate (ATP) combination which has high enegy phosphate bonds stoed in skeleton muscula tissue (Scott, 2005; Guyton & John, 20; McAdle, 2000; Foss, 998; Åstand & Rodahl 986). The ATP amount needed fo the contaction of skeleton muscles at the physical activities is supplied by thee diffeent enegy systems. The selection of which enegy system to be activated is detemined by duation and intensity of the activity. The immediate enegy is supplied by ATP-PC system, the shot tem enegy is supplied by glycolytic system and the long tem enegy is supplied by aeobic system (Guyton & John, 20; McAdle, 2000; Foss, 998). The aeobic capacity is linked with the ability of body to use existing oxygen (Svensson & Dust 2005) and it is the highest oxygen utilization that could be eached duing maximal o intense execise pogam. It is stated that the aeobic capacity can be limited depending on the lack of oxidative enzymes in the cell mitochondia o the O2 amount caied to active tissues with ability of cadio vascula system (Wilmoe & Costill, 2005). The anaeobic capacity is the wok capacity ceated by skeleton muscles duing maximal and supamaximal physical activities of less than 90 seconds with the lack of oxygen (Jonathan & Euan, 997). It is stated that the elite socce playes epeat spints of 2-4 seconds in aveage with intevals of 90 seconds (Stolen et al., 2005). Also it is indicated that aeobic way is used as main enegy souce in socce games (Bangsbo, 994; Kustup et al., 2003) and socce playes at elite level un nealy 0 kms with a powe close to the aeobic theshold (80-90 % of maximal heat ate) duing a game of 90 minutes (Stølen et 362

2 al., 2005). Accoding to the liteatue on this field the positive elation between maximal oxygen consumption capacity (VO2max) and distance coveed in the socce matches and (Hoff, 2005; Kustup, 2003; Dust, 998; Reilly, 2003; Fanco, 2005) technical-tactical pefomance of playes is stessed (Apo, 988; Wisløff, 998; Helgeud et al., 200). Integity could not be identified at the studies on the elation between hematological values and execises. Linstedt (200) has shown that maximal oxygen consumption amount has been limited by the cental ciculatoy system duing the execises in which the lage muscle goups took pat. Thee ae numeous studies that stimulation of the hematological paametes ae attibuted to the spotive activities on the chaacteistics of the specific styles such as stength and powe taining. It has been stated that the hemoglobin concentation has inceased eythocytosis (eythocyte incease) stimulation mainly with the effect of execise but this mechanism has been suppessed by the vey lage incease of the plasma volume (Schumache et al., 2002). In this study the elations between diffeent enegy tansfe systems that needed fo pefoming the actions with o without ball duing a socce game and activate accoding to intensity and duation and the hematological values have been obseved. 2. Mateials and Methods The measuements ae pefomed at 4 diffeent days in second week of socce league pepaation season. In the fist day measuements of height and body composition and taking of blood samples have been done. In the 2 nd day Wingate anaeobic powe test (WAnT) application at the socce fitness saloon, in the 3 d day 6 x 30 m epeated spint test and in the 4 th day 20 m shuttle un test have been pefomed. 30 m spint and 20 m shuttle un tests have been caied out at the envionment that 067 mete of altitude, at an outdoo aea, on dy natual tuf and tempeatue of C. Pefomance tests have been stated 2.5 hous late afte beakfast. 3. Paticipants 24 socce playes fom the Tukish 2 nd pofessional socce league paticipated to this study. 4. Expeimental Pocedues Measuement of body composition and heigh The measuement of body composition (body mass, fat mass, fat fee mass) has been pefomed by Tanita TBF 40 Japan, height measuements have been pefomed by a Holtain band (England) stadiomete with a sensitivity of ± mm. The measuement of body composition was pefomed befoe taking of blood samples in fasting state. Taking of blood samples Eythocytes (RBC) and hemoglobin (HGB) measuements at the blood samples taken afte 9 hous of fasting peiod have been done with a Coulte T-890 USA device. Wingate anaeobic powe test (WAnT) WanT test consists of pedaling fo 30 seconds with a maximal speed against a constant foce. Test has been pefomed in 5 intevals as pepaation, ecovey peiod, acceleation, wingate test and cooldown phases espectively. At the pepaation phase (5 minutes) 5 low esistance maximal pedaling speed spints with 4-6 seconds intevals and at the ecovey phase (3 minutes) pedaling with a minimal esistance (0-20 pm kg) and vey low speed wee pefomed. At the acceleation phase esistance was inceased incementally and afte 9-0 seconds it was aised to the pe-detemined level. The paticipant pedaled fo 30 seconds with maximum effot at the wingate test phase and at the end of the pocess came the cooldown phase. This phase included of pedaling with maximum esistance fo 2-3 minutes. The load subjected to cycling pedal was detemined as 75 gams fo each kgs of body mass duing the test (Adams, 2002; Inba et al., 996; Ba-O, 987). 20 m Shuttle Run Test Equipments fo this test ae a CD including 20 m shuttle un test audio wanings, a CD playe, a tape measue, cones and individual foms. The test pocess consisted of pepaation phase, application phase and cooldown phase afte the end of test. Duing the pepaation phase, to catch a standad all socce playe goups paticipating the test have been subjected to a wam-up phase of 0 minutes that has a content pepaed befoe (jog, low un, flexibility, stetching). Duing the test peiod socce playes wee expected to detemine thei unning tempo between the cones in accodance with the voice (ton and bleep) they head automatically fom the CD playe. It was peviously stated that the time inteval between voices would decease afte each minute so tempo would incease (accoding to the voices the unning pace was 8.5 km/h at the beginning and it inceased 0.5 km/h in evey minute. The tests of paticipants who could not each to the place that they had to be twice afte the audio wanings wee finalized (Lége et al., 988). 30 m ve 6 x 30 m Repeated spint test This test was applied in thee phases consisting of wam-up, testing and cooldown peiods. At the wam-up phase (25 min.) each paticipant subjected to vaious activities (containing jog, low un, submaximal /maxsimal un, flexibility, stetching and jump) in accodance with the pedetemined numbe, duation o pace in ode to catch the standad. The paticipants began the spint when they ae eady at high stat position without acceleating and ended at 30 metes. 30 m test measuements of the playes 363

3 passing between stat and stop divisions of photocell wee taken afte photocell automatically stopped. The measuement was pefomed by using new-test 2000 in Finland photocell device with milliseconds sensitivity. Afte the best degee was detemined at the 6 x 30 m epeated spint test pecentage decement at the velocity pefomance due to fatigue (Pecentage decement; % PD) was measued as below: Fatigue % o the pecentage decement (% PD); = 00 [(fastest spint time x 6 / total epeated spint time) x 00 ] (Glaiste, 2004). Statistical Analysis Mean and standad deviation measuements egading the total data wee pefomed. Test of nomality fo data was done with Sample K-S test and the values wee calculated moe than The elation between each datum that shows nomal distibution was eseached with the help of Peason poduct moment coelation analysis. Fo the statistical analysis, a package pogam was used and significance level was accepted as Results The demogaphical specifications of socce playes like age, height, body weight and body mass index (BMI) wee detemined as 22.2 ± 2.0 (yeas), 77.0 ± 4,7 (cm), 7.9 ± 6.4 (kg) and 22.9 ±.5 (kg/m²) espectively (Table ). Afte the 20 m shuttle un test to detemine the aeobic capacity, the maximal oxygen usage (VO2max) was calculated as 53.3 ± 3.6 (ml.kg.min ), with wingate test to detemine the aeobic stength the peak powe (PP) was calculated as. ± 0.9 (watt/kg) and the mean powe (MP) was calculated as 7.7 ± 0.6 (watt/kg) (Table 2). The fastest spint (FS) degee in 30 mete spint test was ecoded as 4.2 ± 0. (sec.) and pecentage decement (PD) o fatigue was ecoded as 2.9 ±.3 (Table 2). The elations between pefomance tests with diffeent chaactes of socce playes wee given at Table 3. Accoding to this, it had been detemined that thee was a positive meaningful elation between maximal oxygen usage and mean powe (P<0.0) and thee was a negative meaningful elation between maximal oxygen usage and the ability of maintaining spint powe (P<0.05). Also it had been seen that thee was a negative elation between peak powe (PP) and the fastest spint (FS) (P<0.05) and fo hematological values thee is a positive elation only between themselves (P<0.0) (Table 3). Table. Demogaphic chaacteistics and body composition of socce playes; mean ± standad deviation (SD), minimum and maximum values. n = 24 Mean ± SD Minimum Maximum Age (yeas) 22.2 ± Height (cm) 77.0 ± Body mass (kg) 7.9 ± Body mass index; BMI (kg/m²) 22.9 ± Table 2. Aeobic and anaeobic powe, fastest spint, spint powe maintenance, hematological of socce playes; mean ± standad deviation (SD), minimum and maximum values. N = 24 Mean ± SD Minimum Maximum Maximal oxygen consumption (ml. kg. min ) 53.3 ± Peak powe (watt/kg ). ± Mean powe (watt/kg) 7.7 ± Fastest spint (sec.) 4.2 ± Pecentage decement 2.9 ± Eythocytes (0 2 / L; M/mm³ ) 5.03 ± Hemoglobin (g/dl) 5. 7 ± VO2max;, RBC;, HGB; Hemoglobin, 364

4 Table 3: The pefomance test esults of socce playes with diffeent chaacteistics and the elation between hematological values. VO2max PP MP FS PD RBC HGB VO2max (**) (*) P PP (**) P MP (**) P FS P.398, PD P RBC.758 (**) P.000 HGB P VO2max: Maximal oxygen consumption, PP: Peak powe, MP: Mean powe, FS: Fastest spint, PD: Pecentage decement RBC; Red blood cells o eythocytes, HGB; Hemoglobin, * Coelation is significant at the 0.05 level (2-tailed), ** Coelation is significant at the 0.0 level (2-tailed), 6. Discussion In socce physical demands equies the playes to be adequate on the aspects such as aeobic and anaeobic powe, muscle stength, flexibility and agility (Svensson & Dust, 2005). In this study that pefomed with the paticipation of national level pofessional playes it has been seen that diffeent enegy tansfe systems depending the intensity and time ae inteacting with each othe in some level independent fom the hematological values (aeobic and anaeobic) (Table 3). Hee the aeobic capacity epesents metabolic paamete and VO2max in figues is a significant pefomance indicato individually in socce (Bangsbo, 994). The VO2max value fo elite male playes was epoted by Wisloff et al., (998), Reilly (994) and Hoff (2005) is between ml/kg /min, between ml/kg /min by Wilmoe and Costill (2005) and between ml/kg /min by Goe (2000). The eason fo the VO2max esults in this study is lowe than the values stated at the liteatue can be attibuted to the eality that these socce playes ae just at the beginning of the pe-season pepaation phase (Table 2). The stong, positive elation found in this study between MP value which is the indicato of the lactasid section of wingate anaeobic test (Inba & Ba-O, 986; Wilmoe & Costill, 2005) and aeobic capacity ( =.605; P < 0.0) (Table 3) can be consideed as a suppoting data fo the knowledge that highe aeobic capacity will be tansfeed to the anaeobic capacity positively. WAnT is a pefomance test that pefomed with the contibution of diffeent enegy tansfe systems (Spence et al., 2005). It was epoted that the aeobic system has contibuted to the total enegy poduction with a pecentage of 3-44% duing this test (Gastin, 200 The negative elation between peak powe (the powe poduced pe kg in 5 seconds) value with alactacid quality belonging to Wingate test and the fastest 30 m spint time (= -.58; p < 0.0) (Table 3) indicates that the simila time (4 to 5s) and loading intensity (maximum) ae bought about with the same type enegy tansfe system (ATP-PC) (Wilmoe & Costill 2005; Guyton, 20). But Meckel et al., (2009) found no any elation between the fastest spints at 40m and 20m and WAnT peak powe and they have asseted that the eason of that esult is in wingate test only leg and in spint test only big muscle goups ae included to the activity. In socce match analyses the quick ecovey abilities of elite socce playes at high intensity execise peiods ae pioitized. Fo this eason, the ability of socce playes equies consecutive high intensity spint actions with o without ball (Moh, 2003). The stong elation between epeated spint 365

5 test fatigue pecentage as an indicato of maintaining spint quality and maximal oxygen consumption has been poved by the MP value as an indicato of wingate test lactate pat ( = -.802; P<0.0) (Table 3;). The simila esults by means of time and powe at these pefomance tests, despite one of the tests was pefomed on fixed cycle can be taken as the eflection of using both enegy souces (ATP-PC and glycolytic systems) (Wilmoe & Costill 2005; Guyton 20). In a study caied out with 33 elite socce playes of 6-8 age inteval in the middle of the season the coelation in a level of P<0.05 between VO2max and 2 x 20m epeated spint test (RST) pefomance decement (PD) was detemined but it was epoted that thee was no elation between 6 x 40m RST pefomed with intevals of 30 seconds and PD (Meckel et al., 2009). Thee has been a modeate elation between 8 x 40m RST with a esting intevals of 30 seconds and VO2max (Aziz et al., 2000), no elation was epoted 6 x 20m RST with a esting intevals of 20 seconds and VO2max (Aziz et al., 2007). It has been stated that high intensity activity level of pemiee league socce playes in league matches meaningfully affects the success ating of thei teams Di Salvo et al., (2009). The ability of epeated spint has been affected by ecovey time between spints (Bogdanis et al., (996). Although it has been said that in socce pefomance distance coveed with high powe is moe impotant than the total distance coveed and thee is a elation between distance coveed with high powe and VO2max (Bangsbo & Lindguist, 992) thee ae vaious studies in which the positive elation between the distance coveed in socce matches and VO2max has been stessed (Hoff 2005; Kustup, 2003; Dust, 998; Reilly, 2003; Fanco, 2005). The efficiency aspect of aeobic enegy system has been the dominant view in detemining the ecovey ate afte intense activities (Kustup et al., 2003; Spence, 2005; Glaiste, 2005; Meckel et al., 2009). It has been stated that the execises with aeobic chaacteistics has a positive and meaningful change in all of the socce game components such as spint numbe, inteception abilities, completed o uncompleted passes, distance coveed and VO2max values (Helgeud et al., 200). This poves that VO2max has an effect on enegy tansfe metabolism takes pat duing the pefomance of activities with diffeent powe values. No elation has been detected between hematological values of socce playes and pefomance values shown though aeobic and anaeobic mechanisms (Table 3; p>0.05). An assessment of situation (the level at that moment) about hematological index of socce playes was (Cazzola, 2000; Schumache et al., 2002; Nikolaidis et al., 2003; Fallon, 2004; Segej, 2004) pefomed, in some studies it was epoted that these values occued duing measuements pefomed all thoughout the season with cetain intevals ae not consistent but eventually thee is no meaningful change (Silva et al., 2008, Filaie et al., 2003). At the study in which the physical and physiological chaacteistics of elite and non-elite Sebian socce playes, it has been obseved that thee is no hemoglobin value diffeence despite thee is a meaningful age and VO2max diffeences between goups (Segej, 2004). At the measuements pefomed at the beginning, middle and end of the 2 week pocess with the paticipation of 2 pofessional socce playes who ae membe of same team at national level no coelation has been detected between anaeobic theshold and hematological paametes (Silva et al., 2008). In some studies the elation between VO2max and hemoglobin (Kanstup & Ekblom, 984; Goe et al., 997) was mainly attibuted to muscle adaptations at anaeobic theshold (Billat et al., 2003). Because thee has been no incease at the eythocyte amount in acute execises, expecting an incease at the hemoglobin amount was not seen meaningful. It was stated that ed cell (eythocyte) and hemoglobin levels was inceased as a esult of hemoconcentation just afte the ulta maathon aces of 56 and 60 kms and highest hemodillution at the ecovey peiod afte the 60 km ace was 48 hous afte the ace (Viu & Viu, 200). When this study and the pevious ones has been taken into consideation no integity was seen at the elation especially between eythocyte and hemoglobin values of spotsmen and the pefomance levels whethe in coss-sectional o longitudinal studies. This situation makes out the effect of oxygen tanspotation, oxygen uptake ate, oxygen debt, mitochondial intensity, oxidative mechanisms, cetain execise conditions and types along with cental component (Cadiac Output) which is one of the limiting factos that egulates the existing oxygen uptake (Linstedt, 200; Joyne, 2008). It is appaent that diffeent enegy tansfe pocesses that meet the enegy need at the physical activities and changes based on time and intensity affect each othe. Developing the aeobic and anaeobic components in concodance with suitable execise loading will be a possible esult fo development of the ecovey ability. This change will especially help to maintain high intensity effots and incease the numbe of activities in high intensity with shot tem. This compatible featue that affects individual and team pefomances will take an impotant ole at the success. The ability to continue 366

6 high intensity activities duing the match will also positively affect biomechanics and aesthetics of the pefomance of taget play with o without the ball. The playes being away fom the aea whee the ball is played will possibly decease the activity intensity duing that peiod. Making the ecovey peiod moe efficient will make it possible to make the playe who would take a ole at the continually changing fom and tempo of the game especially physiologically eady befoe tying a high powe activity. Without ignoing the individual abilities, the peson who plans the execises should employ a loading pogam that has content enables the playes to use the time intevals duing the match most effectively. Refeences. Adams, G. M. Execise physiology, laboatoy manual. Bston: WCB/McGaw-Hill companies, 2002: Apo, P. Successful fomulae fo fitness taining. In: Reilly T, Less A, Davids K, Muphy WJ, eds. Science and football. London: E & FN Spon, 988: Astand, P. O., Rodhal, K. Textbook of Wok Physiology. Physiological Bases of Execise. McGaw-Hill Book Company, New Yok, Aziz, A.R., Chia, M, and Teh, K.C. The elationship between maximal oxygen uptake and epeated spint pefomance indices in field hockey and socce playes. J Spots Med Phys Fitness, 2000; 40: Aziz, AR, Mukhejee, S, Chia, M, and Teh, KC. Relationship between measued maximal oxygen Uptake and aeobic enduance pefomance with unning epeated spint ability in young elite socce playes. J Spots Med Phys Fitness, 2007; 7: Bangsbo, J. The physiology of socce with special efeence to intense intemittent execise. Acta Physiologica Scandinavia 994; 5(69): Ba-O, O. The wingate anaeobic test: an update on methodology eliability and validity, Spots Medicine, 987; 4: Billat, V.L., Sivent, P., Py.G.K., Koalsztein, J.-P. & Mecie, J. The concept of maximal lactate steady state. A bidge between biochemisty, physiology and spot science. Spots Medicine 2003; 33: Bogdanis, G.C., Nevill, M.E., Boobis, L.H., and Lakomy, H.K. Contibution of phosphoceatine and aeobic metabolism to enegy supply duing epeated spint execise. J Appl Physiol 996; (80): Bompa, O. T. Peiodization: Theoy and methodology of taining, 4th ed. Champaign, Illinois: Human Kinetics, Cazzola, M.A. A global stategy fo pevention and detection of blood doping with eythopoietin and elated dugs. Haematologica, 2000; 85: Di Salvo, V., Baon, R., Tschan, H., Caldeon Monteo F.J., Bachl, N., Pigozzi, F. Pefomance chaacteistics accoding to playing position in elite socce. Int. J. Spots Med. 2007; 28(3): Dust, B., Reilly, E. and Rienzi, E. Analysis of wok ate in socce. Spots Execise and Injuy, 998; 4: Fallon, K.E. Utility of hematological and ionelated sceening in elite athletes. Clinical Jounal of Spots Medicine 2004; 4: Filaie, E., Lac, G. & Pequignot, J.-M. Biological, homonal and psychological paametes in Pofessional socce playes thoughout a competitive season. Peceptual and Moto Skills 2003; 97: Foss, M. L., Keteyian, S.J. Fox s Physiological Basis fo Execise and Spot. 6th ed. WCB/McGaw-Hill, Fanco, M. Impellizzei, Emanno Rampinini, Samuele M. Macoa. Physiological assessment of aeobic taining in socce. Jounal of Spots Sciences, 2005; 23(6): Gastin PB. Enegy system inteaction and elative contibution duing maximal execise. Spots Medicine, 200; 3(0): Glaiste, M. Multiple spint wok: physiological esponses, mechanisms of fatigue and the influence of aeobic fitness. Spots Med. 2005;35(9): Glaiste, M. Multiple spint wok: physiological esponses, mechanisms of fatigue and the influence of aeobic fitness. Spots Med. 2005;35(9): Goe, C.J. Physiological Tests fo Elite Athletes. Champaign: Human Kinetics: USA; Goe, C.J., Hahn, A.G., Buge, C.M. & Telfod, R.D. VO2max and hemoglobin mass of tained athletes duing high intensity taining. Intenational Jounal of Spots Medicine 997; 8: Guyton, A.C., John, E. H. Textbook of Medical Physiology. 2th Edition, impint by W.B. Saundes Company, Helgeud, J., Engen, C. L., Wisloff, U. & Hoff, J., Aeobik Enduance Taining Impoves 367

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