Comparison of Physical Capacities Strength and Speed of Different Competition Level Football Players

IntroductionThere are several studies in literature that report soccer is a dynamic, complex, and particularly demanding sport. Soccer, as a typical intermittent-type sport, incorporates various explosive motions such as sprinting, kicking, jumping, tackling, changes of direction, and turning (Reilly, Bangsbo, Franks, 2000; Reilly, Hoff, Helgerud, 2004; Wisloff, Castagna, Helgerud, Jones, Hoff, 2004; Mohr, Krustrup, Bangsbo, 2005; Bangsbo, Mohr, Krustrup, 2006; Spori, Jukic, Ostojic, Milanovic, 2009). Strength, power, and their derivatives, acceleration, all make important contributions to the performance potential of soccer players (Reilly, Bangsbo, Franks, 2000; Hoff & Helgerud, 2004). There are also reports in the literature concerning investigations which studied the strength of soccer players (Oberg, Moller, Gillquist, Ekstrand, 1986; Wisloff, Helgerud, Hoff, 1998; Cometti, Maffiuletti, Pousson, Chatard, Maffulli, 2001; McBride, Triplett-McBride, Davie, Newton, 2002; Newman, Tarpenning, Marino, 2004; Ronnestad, Kvamme, Sunde, Raastad, 2008; Tonnessen, Shalfawi, Hauge, Enoksen, 2011) and the speed of football players (McBride et al., 2002; Newman et al., 2004; Ronnestad et al., 2008; Tonnessen et al., 2011). In addition we can see significant differences between soccer players of different levels of competition, and soccer teams of different divisions in strength, vertical jump, and sprint performance (Oberg et al., 1986; Cometti et al., 2001; McBride et al., 2002; Newman et al., 2004; Ronnestad et al., 2008). The evaluation of force-time curve characteristics, vertical jump ability, and speed has been used for strength and speed diagnosis and to monitor the effects of training in soccer players (Oberg et al., 1986; Cometti et al., 2001; McBride et al., 2002; Newman et al., 2004; Ronnestad et al., 2008; Gissis et al., 2006; Gissis, 2012). The purpose of this study was to assess the physical abilities of strength and speed of soccer players of different divisions. In order to draw conclusions which will be used in training plans.MethodsParticipantsForty two (n=42) soccer players were divided into three groups according to competition level: elite class football players of higher division (η = 14), middle class football players of middle division (η = 14) and lower class football players of lower division (η = 14) (Table 1). MeasureThe measurements were conducted in the Sport Biomechanics Laboratory of the Department of Physical Education in Serres (Aristotle University of Thessaloniki). Isometric ForceA specially designed leg-press apparatus was used for the measurement. Maximal isometric force of the bilateral leg extensor muscles was measured in a sitting position (knee and hip angle 90 degrees) (Gissis, I., Papadopoulos, C., Kalapotharakos, V.l., Sotiropoulos, ? ., Komsis, G., Manolopoulos, E., 2006; Papadopoulos, C., Kalapotharakos, V.l., Nousios, G., Meliggas, K. Gantiraga, E., 2006; Gissis, 2012). Three trials were completed by each participant, separated by 3 min. intervals, and the best performance was used for the subsequent statistical analysis. During maximum isometric effort a non movable-back chair was supporting the trunk, while the subjects had their hands on the dynamometer grips. Calibration of the measurement system was achieved by using weights (5, 10, and 20 kg weight discs) from 50 to 600 kg. Input (input = weight) and output values (output = electric signal) presented a distinct linearity. Reliability indexes ranged from . 92 to . 95 for the isometric strength.Vertical Jump AbilityVertical jump ability was evaluated using a one-dimensional dynamometer. Before the initiation of the measurements, a 10 min warming up was applied. All participants performed the following laboratory test items: a) squat jump from a static semi-squatting position with a knee angle 90° without using arms, b) drop jump from stands of 10 cm, c) drop jump from stands of 20 cm, d) drop jump from stands of 30 cm and e) drop jump from stands of 40 cm (Bobbert, Huijing, van Ingen Schenau 1987; Papadopoulos et al. …