# Home Advantage in Football: Exploring Its Effect on Individual Performance  
[PERSON]  
1 Department of Physiotherapy, Faculty of Medicine, Health and Sports, European University of Madrid, Villavicios de Odon, 28670 Madrid, Spain; [EMAIL_ADDRESS] (G.B.-C.)  
1 Department of Physiotherapy, Faculty of Medicine, Health and Sports, European University of Madrid, Villavicios de Odon, 28670 Madrid, Spain; [EMAIL_ADDRESS] (E.C.-F); gerardbrunso@gmail. over 10 seasons (2003/04 to 2012/13), introducing the correlation of HA (independent of other teams' HA) with \"away disadvantage\" [10]. Although isolating the impact of each factor is challenging, several variables have been identified as potentially influencing HA, including crowd support, travel distance, familiarity with the stadium, referee decisions, territoriality, tactical choices, rule changes, and psychological factors. These variables are interrelated and often interact in complex ways [3; 9; 11]. Recent studies have found that the HA effect is more pronounced in sports with higher levels of physical contact, mainly due to crowd influence, which puts pressure on both the team and referees. Additionally, research has shown that HA is influenced by the league level [2; 4; 5; 12]. A possible explanation is the higher attendance of supporters in top leagues compared to lower divisions [2; 13; 14; 15]. As previously concluded, Inan attributed a significant impact to crowd support and stadium capacity in the five major European soccer leagues (Bundesliga, La Liga, Ligue 1, Premier League, and Serie A) between 2014 and 2019 [3]. Home teams performed particularly well in the Bundesliga, securing 70.45% of contested points (863 wins or draws). In La Liga and Ligue 1, the percentages rose to 71.65% and 71.51%, respectively. In the Premier League and Serie A, the percentages were 69.67% and 69.07%. The influence of fans on all aspects of a match (home team, away team, referees, etc.) became especially evident during the COVID-19 restrictions, when games were played without fans, reducing HA to a minimum or even eliminating it, according to some authors [16; 17; 18; 19]. Recent evidence points to referee decisions as the primary explanation for the HA effect [13]. One of the reasons HA decreased during COVID-19 was the lack of crowd influence on referees [20; 21]. A study analysing the cognitive behaviour from a neuroscientific perspective found that referee experience influenced decision-making, as they sought to avoid negative feedback and pursue the \"dopamine reward\" [21]. Similarly, refereeing bias has been observed in yellow and red card distribution. In a study of European competitions (UEFA Champions League and UEFA Europa League) during the 2009-2010 and 2011-2012 seasons. [PERSON] found that away teams received 25% more yellow cards than home teams in the Champions League and 10% more in the Europa League [22]. The study concluded that the bias in favour of home teams in the Champions League was primarily due to larger crowd sizes. [PERSON] et al. analysed the goals, yellow cards (home = 1.1, away = 1.6), red cards (home expulsions = 0.06, away expulsions = 0.09), and penalties (home = 0.1, away = 0.05) in the Premier League, concluding that referees granted a greater advantage to home teams [23]. Beyond crowd influence and refereeing decisions, other contextual factors contribute to HA. Location, distance, and altitude at which matches are played can also influence the HA effect. Although travel times have decreased due to advancements in transportation [24], a study of the Brazilian league observed a greater HA effect in teams from the north and south compared to those from central regions, possibly due to the effects of travel [11]. Altitude can also be a significant factor, as changes in atmospheric pressure and reduced oxygen levels impact performance [13; 25].