Research On The Running Performance And Energy Cost Of University Male Soccer Players In Small-Sided Games

To understand and master the load of football project is helpful to improve the understanding of the characteristics of football project in the academic circle.The main component of football external load is running performance,and the concentrated expression of internal load is energy consumption.With the deepening of practical application and the upgrading of research technology,global positioning equipment has been widely used in football and other collective ball projects.However,the attention of the academia to the global positioning equipment is mainly on the external load,and the accuracy of the equipment in measuring the internal load such as energy consumption is rarely reported.The common method of football training is small field match.It is not known how different types of small field match affect the running performance and energy consumption of players.It is not known whether there are differences in the performance of players in different positions in small field match.In order to answer the related questions,this study first tested the validity of the global positioning equipment in measuring the energy consumption of football straight-line running and variable-speed running;secondly,using the global positioning equipment and the calculation formula of the energy consumption of variable-speed running,it studied the common small field matches in football training,and explored the impact of different types of small field matches on running performance and energy consumption;finally It analyzes the running performance and energy consumption of players in different positions in small field competition.First study(Chapter Three)is to compare the difference of energy cost between straight-line and CoD running of male football players.20 male football players from university were recruited to measure the energy cost of straight-line running and 20m 180° CoD running under the step-by-step increasing speed(speed 7.5-10.0km/m,0.5km every 3 minutes)by using gas analyzer(K4b2)and global positioning equipment(ctatpuls S5).The results show that:in 7.5-10.0 km/h,the energy cost measured by gas analyzer is 4.42-4.65J·kg-1·m-1,which is significantly lower than that of the energy cost measured by GPS(5.65-6.64J·kg-1·m-1),which is significantly lower than that of gas analyzer(4.89-5.65J·kg-1·m-1).The average difference of energy cost measured by two methods under straight line running is 0.29J·kg-1·m-1,which is significantly lower than that under the CoD running(0.93 J·kg-1·m-1).It shows that in the low-speed,the energy cost of 20m 180°CoD running increases with the speed.The consistency of gas analyzer and global positioning equipment is good when measuring the energy consumption of straight-line running,but decreased when measuring the change direction running.Considering that the running form of football consist of straight line and CoD,it has practical significance to measure the load with the help of global positioning equipment..Second study(Chapter Four)is to find the influence of three kinds of SSGs(4v4,6v6 and 8v8)on the running performance and energy cost of university men's football players,and compares the difference of the proportion of high-intensity activities under the two criteria.Using global positioning equipment,the running data of 20 male football players in SSGs were measured.The energy cost was calculated based on the calculation formula of acceleration.The results showed that the total running distance increased significantly with the increase of the number of players,the middle speed running distance of 8v8 small field races was significantly higher than 6v6 and 4v4,the middle and high speed running distance and high speed running distance of 4v4 were significantly lower than 6v6 and 8v8,the total changing speed and low deceleration decreased significantly with the increase of the number of players,and middle acceleration and middle deceleration were significantly higher than 6v6 and 8v8.The energy cost and metabolic power increased significantly with the increase of the number of players,the proportion of high-intensity activities(11.35-13.34%)classified by running speed was significantly lower than energy cost(17.00-18.07%).It shows that in a certain range,SSGs with a large number of players is more suitable for the development of running ability,and SSGs with a small number of players is more suitable for the development of agility abilities.According to the standard of running speed,the proportion of high-intensity activities is underestimated,which is especially obvious in SSGs with a small number of players.Third study(Chapter Five)is to analyzes the running performance and energy cost of male football players in different positions in SSGs.The data of 100 non-goalkeepers players from 18 SSGs were standardized(1min).The results showed that:the total running distance,low-speed running distance,middle speed running distance and middle high-speed running distance showed the difference in position.The total speed change times of forwards were significantly higher than that of midfield,the maximum speed up times of forwards were significantly higher than that of midfield and guards,the maximum speed down times of guards were significantly higher than that of midfield.The energy cost of midfield was significantly higher than that of forwards and guards,the energy cost of forwards was significantly higher than that of guards.It shows that the running performance and energy cost of college men's football players in SSGs have obvious position characteristics.The requirements of SSGs on the running ability of midfield,the high acceleration starting ability of forward and the high deceleration braking ability of guard are obviously higher than other positions.In SSGs,the proportion of high-intensity activities with running speed as the division standard is significantly lower than the energy consumption,which is more prominent in the position with higher requirements for high-intensity activities.In conclusion,this research found that:1)compared with the portable gas analyzer,the global positioning equipment has a certain validity in measuring the energy cost of CoD running.2)Coaches should combine the running distance,the number of speed changes and energy cost of players in different SSGs to arrange the SSGs plan,and develop the physical performanc of players.3)SSGs has a significant effect on the development of the running ability of the midfield,the acceleration ability of the forward and the deceleration ability of the guard.4)In soccer practice and training,it is suggested that the energy cost should be taken as the division standard of the proportion of high-intensity activities,so as to reflect the load characteristics of soccer more objectively.