The Analysis of Running Distances in National Teams in 2010 and 2014 FIFA World Cup and Estimation of Oxygen Consumption Capacity Based on These Distances

This study aims to analyze running distances in national teams during 2010 and 2014 FIFA World Cup and to propose a new program which estimates oxygen consumption capacity based on running distances. The data were evaluated by SPSS 22.0 statistical package program. The findings demonstrate that among teams participating in 2010 and 2014 FIFA World Cup, the lowest average running distance and estimated VO2max values belong to Brazil with 7398.77 meters and 43.84 ml/kg/m, respectively. On the other hand, the highest average running distance and estimated VO2max values belong to Australia with 10598 meters and 67.69 ml/kg/m, respectively. The average running distance and estimated VO2max value in national teams participating in 2010 FIFA World Cup was 9635.54 meters and 60.52 ml/kg/m, while they were 9095.82 meters and 52 ml/kg/m in 2014 FIFA World Cup, respectively.


Introduction
Historical developments and natural conditions (pitch conditions, cultural values and physical features) lead to the emergence of different playing styles in different regions and countries of the world. There are different schools in various countries of the world, and each school brings a new taste to football. For instance, English football attaches importance to running, physical tackling, long passes and a high tempo until the end of 90 minutes. Brazilian football seems to have reached the highest elegance on the pitch. On the other hand, German and Dutch football is based on a more detailed technical game plan, and requires long running distances (Wahl, 2005).
The energy spent during a football game requires players to possess some physiological capacities, which are directly associated with player's physical condition and training methods. Football requires different approaches depending on the playing style, position on the pitch and difficulty level of the match. All players need to possess the ball during the game, and become fast and active in order to support their teammates for defensing and attacking. They are often expected to run for 90 minutes and support the teammate possessing the ball in a suitable position on the pitch (Reilly, 2003).

Methods
The average running distances during the tournament were used to estimate running distance in these national teams. (M-0.3138)/0.0.278 formula, which was developed by Cooper (Cooper, 1968) was used to estimate approximate VO2max values of the teams. The numbers in this formula (1), which enables to estimate VO2max values during 12 minutes, were multiplied by 3 in order to estimate VO2max values for 36 minutes. In a football match, during a half of 45 minutes, nearly 9 minutes are spent passively (penalty kick, free kick, goal kick, fouls etc.). Thanks to our modified formula, a new VO2max formula was developed in order to approximately estimate running distances in a football match. As a result, oxygen consumption of the players in a team was estimated based on their running distances. VO 2 max= Running Distance-0.9414/0.0834 (1) [Running Distance/1 mile (1.609m)] Direct VO 2 max estimation may pose threats to a player's life because it needs to be measured on his respiratory, circulatory and heart system. In fact, it is compulsory to maintain a medical staff during a VO 2 max measurement. Nevertheless, as mentioned above, methods for VO 2 max measurement have not been developed yet. These estimations usually yield results similar to direct VO 2 max measurements. However, these methods are called "sub-maximal measurements" because circulatory and respiratory systems are not fully activated.

VO 2 max Test
The average running distances during the tournament were used to estimate running distance in these national teams.
Direct VO2max estimation may pose threats to a player's life because it needs to be measured on his respiratory, circulatory and heart system. In fact, it is compulsory to maintain a medical staff during a VO2max measurement. Nevertheless, as mentioned above, methods for VO2max measurement have not been developed yet. These estimations usually yield results similar to direct VO2max measurements. However, these methods are called "sub-maximal measurements" because circulatory and respiratory systems are not fully activated.

Statistical Analyses
After the data were analyzed through the SPSS 22 software program, descriptives statictics analysis was used to the analysis of running distances in national teams in 2010 and 2014 FIFA World Cup and estimation of oxygen consumption capacity based on these distances.

Discussion
It can be observed that a player's running distance has increased in the last ten years. For instance, average running distance is nearly 11.000 meters in 90 minutes. Because players playing in different positions on the pitch perform different duties, midfielders', defenders' and forwards' running distances are estimated to be 11.4, 10.1 and 10.5 kilometers, respectively. It can be stated that a player's running distance during a football match varies between 8 and 11 kilometers. A football player performs different activities during a match such as standing (17.01%), walking (40.4%), low tempo running (35.1%), high tempo running (8.1%), high tempo sprint (0.7), as well as other activities such as tackling, headers and shooting, dribbling, and jumping (Günay, & Yüce, 1996). The close proximity of football players with an average MaxVO 2 values of 55-65 ml/kg/min to long distance runners underlines the importance of the aerobic energy spent by these players (Marangoz, & Genç ay, 2017 (2000) reports that VO 2 max values of two groups of 16 players in Serbian First and Third Football League was measured as 53.5 ml/kg/min and 42.9 ml/kg/min, respectively. Edwards et al. (2003) found out that VO 2 max value of 20 players in English Premier League was 62.1 ml/kg/min. In a study on 20 elite football players in Irish League, Mclntyre (2005) observed that VO 2 max was calculated as 57.6 ml/kg/min. In a study on 72 footbal players in Japan, Tahara et al. (2006) reported VO 2 max as 54.0 ml/kg/dk.
Although the highest VO 2 max value measured in studies on football players is 80 ml/kg/min, this value is nearly 55-68 ml/kg/min for male football players except goalkeepers. It can be observed that VO 2 max values measured in recent years have varied between 61.1 and 70.7 ml/kg/min in recent years (Aşçı, 2003).

Conclusion
In conclusion, the modified formula developed for this study to estimate oxygen consumption capacity measured VO 2 max levels of national teams participating in 2010 and 2014 FIFA World Cup as 60.52 ml/kg/min and 56.50 ml/kg/min, respectively. It can be argued that these values are lower than VO 2 max values measured in recent years. It was also demonstrated that average running distances of national teams participating in 2010 and 2014 FIFA World Cup were nearly 9500 meters, which is lower than the running distances measure in recent years. Finally, no significance or correlation was observed between running distance and success in the tournament.