Refereeing decisions, testosterone levels and lack of confidence.
Home advantage – meaning sports teams generally play better at their home stadium – is a well-established fact in almost every sport.
But why does this happen?
A study bringing together the results of previous research examined factors including being familiar with local conditions (found to be of “little benefit”) and travel distance (found to have an effect “provided the journey involved crossing a number of time zones”).
The factor found to have the most effect was the crowd – whose main impact was to “influence the officials to subconsciously favour the home team”.
So poor away results may not be due to poor performance.
But there is evidence home advantage affects players.
One study found testosterone levels in football players were “significantly higher” during home games.
It has also been suggested that winning games at home increases the number of androgen receptors (which receive testosterone) in a part of the brain that controls social aggression – a change described as the “winner effect”.
Heightened testosterone levels – possibly linked to a “territorial response” like that seen in many animals – may lead to more aggression and confidence.
But none of the above explanations seem adequate to explain the large effect of home advantage in football – which has been worth about 0.5 points per game in the Premier League in recent years.
So maybe a combination of factors is responsible – and maybe widespread belief in home advantage is one of these. It’s certainly common for football teams to play more defensively away from home.
This negative attitude may be the most important factor of all, as it may rob the away team of a vital weapon – confidence.