Soccer is an intermittent sport in which the aerobic and anaerobic capacity of the players are both essential. Elite football players perform an average of 150-250 short and intense movements during a match, demonstrating the significant contribution of the anaerobic energy system. Sided-games is a tool to enhance the performance of the aerobic and anaerobic system. This training includes actions such as sprinting, changes of direction, accelerations, decelerations, jumps, and shooting, characterized by a strong eccentric component. Eccentric actions are associated with exercise-induced muscle damage (EIMD). Nevertheless, to date, EIMD responses following a session of sided games training have not yet been investigated. Therefore, the present study aims to examine the speed of recovery after training with a large-dimension pitch area with a small and large number of athletes in football.

Football is an intermittent sport that includes actions of variable intensities and combines elements of physical fitness with technical and tactical skills. The game is characterized by a combination of several short-term movements such as jumps and change of direction. Typically, a player in a soccer game changes his kinetic situation every 4-6 seconds. The mean and maximum heart rate during the fight is approximately 85% and 98% of the maximum heart rate, respectively, while the average oxygen uptake is 70% of the maximum, proving that the aerobic system contributes significantly during the game. In addition, the lactic acid value in the blood ranges from 2 to 14 mM, which proves that also the anaerobic energy system contributes significantly during a game. Based on the above, the training of soccer players must meet the physiological and physiological requirements of the game.

There are two approaches to developing fitness. In the first, there is a distinction between fitness training technical skills and tactics, while the second attempts to achieve all of them at the same time, and for that purpose, the sided games are used. The first approach refers to the literature as a traditional form of physical fitness training and contains the ball and run exercises. It is part of the training unit and separates the physical conditioning from the technique and tactics, resulting in longer training time. Moreover, although this training achieves the necessary physiological adaptations, the piece of game specialization is missing. For this reason, coaches have been interested in the sided games with restrictions, combining physical, technical, and tactical elements. The coach can modify these games to achieve the training goal each time. During training with racing blocks, a similar or even higher heart rate has been observed on soccer players compared with the short-term intermittent exercise. The intensity of the exercise on the sided games is controlled by several variables that the coach can modify according to the training goal. Many variables can affect the training load such as pitch area, the number of players, and other restrictions (e.g., goalkeepers, contact limitation, etc.). In the application of sided games with large dimension and a small number of players, the maximum heart rate can reach 84-90% while with a large number of players it can reach 84-88%. There is a lack of references regarding rehabilitation after the implementation of sided games, and especially after the execution of large-dimension pitch area with a small and large number of athletes. The aim of the proposed study is, therefore, to examine the speed of recovery after training with a large-dimension pitch area with a small and large number of athletes in football.

Inclusion Criteria:

1. Absence of any musculoskeletal injury for at least 6 months prior to the study
2. No use of any drugs or ergogenic supplements for at least 6 months prior to the study
3. Absence of regular soccer training for the last 3 years

Exclusion Criteria:

1. Any recent incidence of musculoskeletal injury
2. Use of any drugs or ergogenic supplements for the last 6 months
3. Regular soccer training for the last 3 years-