**Abstract**

In games such as soccer, where the stability and the possibility of replicating game situations are complex, teams and players continually deal with a highly unstable cooperative and non-cooperative environment. Thus, synchronized cooperation among players during training sessions is a fundamental factor, which many times contributes to a team's success. In this context, there are some specific drills that attempt to challenge and create meaningful contexts in order to simulate match situations as closely as possible. Small-sided games are play-sport situations in which all elements of the game interact together in a flexible manner. However, there are a variety of small-sided games in elite soccer, such as possession games and positional games, which may present specific characteristics and stimulate different physical-physiological demands. An adequate selection and implementation of these games may help coaches to promote positive adaptations and performance improvements. Thus, this chapter provides practical tips to modulate the physical-physiological responses and technical-tactical requirements of the players using a variety of game formats during soccer training sessions.

**Keywords:** soccer, ball possession, small-side games, possession games, positional games

### **1. Introduction**

Game theory plays a key role in the applied social sciences. Concretely, it has been used in consequence analysis of "decision-making" in the tactical performance of any given individual in team sports, which is a fact to be considered for the players of the same team as for their opponents [1]. In particular, games such as soccer where the stability and the possibility of replicating game situations are complex, teams and players continually deal with a highly unstable cooperative and non-cooperative environment [2]. From this perspective, players and teams are conceptualized as dynamic, intricate systems, interacting in a nonlinear fashion with the environment. Therefore, exposure to challenging and meaningful contexts pushes the exploration and discovery of new synergies, promoting co-adaptive processes between players and transforms sports into dynamic entities [2]. Thus, synchronized cooperation among players is a fundamental

factor, which many times contributes to a team's success. This phenomenon will be substantially more favorable than the fictitious sum of the technical and motor qualities inherent to each player belonging to that team [1]. In this context, there are some specific drills such as "small-sided soccer games" that attempt to challenge and create meaningful contexts in order to simulate match situations as closely as possible.

Small-sided games (SSGs), also referred to in the literature as "game-based training" [3], are play-sport situations [4] in which all elements of the game interact together in a flexible manner [5]. In addition, there are a variety of specific game approaches in elite soccer. The use of such games in professional environments is based on the premise that greater performance improvements are achieved when the specific demands of the sport are transferred [6, 7]. Several studies have shown that the physiological responses of different games can be modified by manipulating variables such as number of players per team [8, 9], modification of certain rules [9], relative area per player [6, 10, 11], comparison with competition [12–14], floaters [15], among others. The authors concluded that these games enable players to get as close as possible to real competitive situations. On account of this, the physical, physiological, technical, and tactical demands of a match can be reproduced to a greater extent.

Moreover, using a weekly pattern with different formats of SSGs in each training session may modulate the player's training load during the micro-cycle [16], which allows a short tapering strategy to face the match with enough energy. Therefore, it might be utilized as a strategy for maintaining or optimizing players' physical performance during the season [17].

As a consequence, coaches and performance staff have made emphasis on and proposed an infinite number of exercises, all of which count with variations in pitch size, number of players in each team, game instructions, and different designs in the shape of the pitch to be used [12, 14]. However, to the best of the author's knowledge, no previous references have been published in order to classify and contrast each kind of game used in elite soccer to train players to reach the physical, technical, and tactical demands of the match. In this context, the present chapter attempts to classify and categorize the different types of specific games and describe their characteristics and the physical-physiological demands.

## **2. The "Conventional Small-Sided Games"**

The SSGs represent one of the most common training elements in soccer at any level and age, as they allow the simultaneous development of technical-tactical contents together with physical goals [18]. In particular, the player's responses during the performance of SSGs have been extensively studied by different authors [12, 19, 20]. In this sense, the advantage of carrying out these games is to replicate real competition situations as closely as possible and thus be able to reproduce very similar physical, physiological, technical, and tactical demands of the game [6, 13]. These types of games can be configured according to a variety of components such as number of players, space orientation, individual interaction space, and balance (whether the teams have the same number of players or are unbalanced by floaters) [12].

The SSGs are collaboration-opposition games [4], which possess a space orientation (one team defending and the other attacking opposite goals), that count with a *"sequence of attacking"* (possession) and *"defending" (*out-of-possession). In this way, two forms of transition are originated: 1) from possession to non-possession of the ball, or 2) from non-possession to possession of the ball [21].
