Michael Kraus, an assistant professor of psychology at the University of Illinois, and Teh-Way David Chen of University of California, Berkeley, did a recent study into the success rate of fighters that smile.
The study was called A Winning Smile? Smile Intensity, Physical Dominance, and Fighter Performance, and the PDF version of their full report can be downloaded here.
Their study took into account 152 unique fighters, or 76 staredowns and fights, between 2008 and 2009.
First, they coded the “intensity” of the smile from 0-2. The three ratings were: a neutral expression, a toothless smile, and a teeth-baring smile. These were compared to the fighter's performances utilizing FightMetric reports. They took in to account their stats from FightMetric, height, and betting odds among other factors.
Winning fighters displayed less intense smiles than losing fighters t(150)=-2.69, p<.01 (see Figure 1, top panel). In a similar analysis, we also compared fighters who won the match in dominant fashion (i.e., winning by knockout or submission) to all other fighters. Again, this analysis yielded the predicted pattern of results: Fighters who won the match by knockout or submission tended to show less intense smiles than all other fighters t(150)=-2.08, p<.05 (see Figure 1, bottom panel).
Taken together, the results from Study 1 provide evidence largely in support of our overarching hypothesis: Increased smile intensity prior to physical combat predicted poorer performance by the fighter exhibiting the smile, and enhanced performance for his opponent.
The weigh-ins are continually a big part of fight week. Fans turn out by the thousands to see fighters make weight and then stare down their opponent. Spectators anticipate the animosity between fighters to provide a certain spark 24 hours before they mix it up in the cage.
Now, with this study, there may be more reason for fighters to avoid acting happy and cordial to their opponent.
Smiling at one's opponent may alter how he fights the next day. He can view that grin as weakness. That his opponent will not be as aggressive, and that he now holds the upper hand. It could potentially give him the confidence boost he needs to outperform his counterpart in the bout.
Kraus has tried implementing this study in to predicting the outcome of fights.
@mbrandt05 i've been trying to make fight predictions based on this study. I've been right on outcome > 60% of the time.— Michael W. Kraus (@mwkraus) March 11, 2013
With UFC 158 just a few days away we can now look deeper into fighters' reactions during the weigh-ins. It gives us, the fans, something more to watch for during those Friday afternoons.
If nothing else, this is an interesting study that looks deeper into aspects of the fight game we rarely think about.
This could be just coincidence, but the findings should perhaps have fighters contemplating more mean mugging at the weigh-ins in the future. Any little bit helps, right?
Now we can await the first fighter to use this as an excuse for a loss.