[audio clip] That’s Rafael Nadal, one of the loudest grunters in tennis  But the real screamers are the women. [audio clip] Ah yes, Maria Sharapova, belting at 101 decibels, is the scream queen. Yet curiously, she doesn’t utter a peep during practice.

But does grunting distract an opponent? Ivan Lendl complained that Andre Agassi’s howls in the 1988 U.S. Open threw off his concentration and timing. And last year the International Tennis Federation began considering banning grunts. Well, maybe a  study in the journal Public Library of Science ONE bolsters the case for a ban.

Thirty-three undergrads watched videos of a tennis player hitting a ball, sometimes with a grunt, sometimes in silence. The subjects had to predict, as fast as possible, the direction of the ball and where it would land, by hitting a keyboard key. And when they heard grunts, the subjects were slower and less accurate.

The researchers say that this is the first study on the impact of grunting in tennis. Now they’re examining how pro players deal with the negative effects of a loud player. But until the ITF rules, it’s up to the umpire to decide if a grunt goes too far.

—Christie Nicholson

[The above text is an exact transcript of this podcast.]