In the world of women’s soccer, the color of a team’s shorts may seem like a trivial detail.
But a new study suggests that it could have a significant impact on a team’s performance.
The study, published on April 18 in the Journal of Behavioral and Experimental Economics, found that women’s soccer teams wearing white shorts scored fewer points per game compared to their opponents wearing non-white shorts.
The study’s author, Alexander Krumer of Molde University College in Norway, analyzed data from the FIFA Women’s World Cup and UEFA European Championships between 2003 and 2023.
He found that women’s teams wearing white shorts scored, on average, between 0.32 and 0.37 fewer points per game than their opponents.
Analyzing the Impact of Shorts Color
The study analyzed a substantial dataset to reach its conclusions.
Krumer examined 391 games from the Women’s FIFA World Cups and UEFA European Championships between 2003 and 2023.
He removed 30 games deemed “uncompetitive,” for example because one of the teams had already qualified for the next stage of the tournament, or because one of the teams had no chance of qualifying; in such cases, teams might not have had the incentive to perform at their best, potentially skewing the results.
Krumer also removed 127 games where both teams had the same color shorts.
The final dataset consisted of 234 games.
In 67.5% of these games (158 out of 234), one team wore white shorts while the other wore non-white shorts.
The analysis revealed that teams in white shorts scored, on average, 1.27 points per game, while their opponents in non-white shorts scored 1.57 points per game.
When controlling for team rankings, home advantage, and other factors through regression analysis, Krumer found that teams in white shorts scored between 0.32 and 0.37 fewer points per game, a statistically significant result.
For comparison, the study also looked at 579 games from the Men’s FIFA World Cups and UEFA European Championships between 2002 and 2022, and found no significant relationship between shorts color and performance for the men’s teams.
The Reasons Behind the Performance Gap
Krumer suggests that the reason for this disparity may be related to the anxiety and discomfort that some female athletes experience while wearing white shorts during their menstrual cycle.
“Female athletes claim that white shorts can make them anxious, or that playing in white shorts is an uncomfortable experience,” Krumer writes in the study.
The menstrual cycle and associated issues are still considered taboo in many societies, leading to a lack of understanding and sub-optimal decision making.
Despite increased awareness, over half the teams participating in the recent 2023 FIFA Women’s World Cup played in white shorts.
A Pioneering Study
Krumer’s study is the first to quantify the potential impact of this anxiety on athletic performance in women’s team sports.
He found that, in any given game, there is a 77.4% probability that one to three players on a team are playing during their menstrual cycle.
This suggests that the anxiety experienced by even a few players could have a significant impact on a team’s overall performance.
This finding supports the idea that the performance disparity in women’s soccer is specifically related to menstruation-related anxiety, rather than a general disadvantage of wearing white shorts.
Implications and Recommendations for Women’s Soccer
The study’s findings have important implications for women’s sports.
“The practical suggestion, which is very easy to implement, is simply to avoid playing in white shorts,” Krumer writes.
Beyond the potential performance benefits, Krumer suggests that addressing this issue could have broader implications for gender equality.
“Given that sport is an important vehicle of gender equality, increased awareness of period anxiety could result in higher participation of women in sports and, ultimately, in narrowing other gender gaps,” he writes.
Journal Reference:
A. Krumer, Journal of Behavioral and Experimental Economics, Volume 110, June 2024, https://doi.org/10.1016/j.socec.2024.102214