2350). Cardiorespiratory endurance can be measured by determining VO2 max values. VO2 max values can illustrate the cardiorespiratory endurance of individuals. The VO2 max of male outfield players lie between 50 and 75 mL/kg/min while female players range from 38.6 to 57.6 mL/kg/min (Stølen et al., 2005, p. 509, p. 511). Elite soccer teams have greater VO2 max values in comparison to other teams. Midfielders were found to have even greater oxygen uptake in comparison to the other positions. While VO2 max is a helpful indicator of endurance performance in the majority of the population, it is more difficult to predict endurance performance in elite athletes using VO2 max. International midfielders have high endurance, but endurance can be limited by the respiratory capacity of the muscles. According to Davies et al. (1982), endurance of running is more dependent on the amount of mitochondria in the muscles than VO2 max with endurance …show more content…
502). The main energy delivery system is aerobic metabolism, but during pivotal moments such as short sprints, jumps, tackles and dual play, anaerobic metabolism is used (Stølen et al., 2005, p. 509). Wide and central midfielders cover more distance than central defenders (Bradley et al., 2010, p. 2348). Because midfielders cover more distance, the aerobic and anaerobic systems are being used to a greater extent than a central defender (Bradley et al., 2010, p. ___). Sprinting covers on average 1-11% of the distance covered in a game (Stølen et al., 2005, p. 503). According to Bradley et al. (2010), wide midfielders cover more distance at high intensity than central midfielders, indicating that they rely more on anaerobic metabolism throughout the duration of a game (p.