FRIDAY, Aug. 15 (HealthDay News) -- Adding another wrinkle to the scientific debate on how color affects humans, a new German study reports that red athletic gear gave a boost to tae kwondo contestants by swaying referees in their favor.
"Competitors dressed in red are awarded more points than competitors dressed in blue, even when their performance is identical," the researchers reported in their study, which was released this week just in time for the Summer Olympics in Beijing.
The study authors contend that it may be necessary to even the playing field by altering rules, perhaps forbidding the wearing of red gear in sports where color could sway the judgment of referees. "We propose that the perception of colors triggers a psychological effect in referees," said study lead author Norbert Hagemann, a psychologist at the University of Munster.
But, an American color researcher said the findings may not tell the whole story because the researchers didn't take certain factors into account.
Scientists have argued for years over whether the color of sports uniforms has an effect on athletic performance. In the new study, the researchers examined another factor -- the effect of color on the decisions of referees.
The study authors asked 42 experienced tae kwondo referees to judge matches shown on video. Tae kwondo, an Olympic sport, is a form of martial art developed in Korea. The researchers chose the sport because a previous study found that the colors worn by participants had a large impact on outcomes, Hagemann said.
With the help of electronic manipulation, the researchers switched the colors of the combatants' protective gear -- head and chest protectors -- so they were blue at some points and red at others.
The researchers then analyzed the scores to see if the uniform colors made a difference. When the contestants seemed to be wearing red, the referees gave them 13 percent more points.
While some colors may help athletes perform better, the researchers wrote, "referees are responsible for the advantage conveyed to athletes who wear red."
But red may not always be a good color for athletes. For example, they may sway referees in soccer to call fouls on players. "One can speculate that the red-clothed players are associated not only with more dominance but also with more aggressiveness, and in ambiguous foul decisions this could be a disadvantage," Hagemann said.
The study findings are published in the August issue of the journal Psychological Science.
Andrew Elliot, a professor of psychology at the University of Rochester who has researched the effects of color, said the study authors erred by not taking into account other aspects of color, such as hue and brightness. These factors could all have played a role in how the officials perceived the colors, he said.
Elliot added that the color red actually seems to intimidate players on opposite teams, instead of boosting the performance of athletes. In some research, "the people in blue are seeing red and they're doing worse. It's not that wearing red leads to better performance," he said.
Why might red be intimidating? People's experiences with the color -- such as red marks on student papers in school or the red of a stop sign -- may affect how the color is perceived, Elliot said. People could then learn to see red as a sign of failure or of potential danger, he said.
"These are extremely basic processes and hard to overcome," he said.
Learn more about how colors can affect moods at Bloomsburg University of Pennsylvania.
SOURCES: Norbert Hagemann, Ph.D., University of Munster, Germany; Andrew Elliot, Ph.D., professor of psychology, University of Rochester, N.Y.; August 2008, Psychological Science