Research shows grunting tennis players hinder opponents

by Deborah Jones
VANCOUVER, Canada, October 2010

For the first time, scientists say they’ve been able to measure the negative effects on professional tennis players of loud grunts made by players such as Maria Sharapova and Rafael Nadal make when hitting the ball.

And an empirical study that measures how much grunting slows down and distracts opponents in tracking the direction of a tennis ball will provide tennis authorities with an objective way to regulate grunting, said Scott Sinnett, lead author of the report.

Grunting noises, which some players make as loudly as 100 decibels, has often triggered complaints in professional tennis, Sinnett said in an interview. The behaviour falls under regulations against making a hindrance but, he said “it’s all subjective, and based on an umpire saying whether it’s too much.”

Regulating tennis-player’s grunts scientifically “could be looked toward, because if it’s distracting to opponent, then it’s basically cheating,” he said.

Researchers played 384 video clips of a tennis player hitting a ball to either the left or right of a video camera, to 33 students at the University of British Columbia in western Canada.

The students were asked to quickly determine whether the ball was hit to the right or left. For some of the shots, a loud white noise was played as the racquet hit the ball.

“When an additional sound occurs at the same time as when the ball is struck, participants are significantly slower …. and make significantly more decision errors,” said the study, published in the journal Public Library of Science ONE.

A growing body of research shows that noise “distracts you from your ability to pay attention from what is going on,” said Sinnett “A grunt doesn’t allow you to place all your attention on what’s happening. It blocks the ability to pay attention to a multi-sensory event.”

Grunting could cause a tennis player to perceive a ball traveling 50 miles per hour to be “two feet closer to the opponent than it actually is,” said Sinnett. “This could increase the likelihood that opponents are out of position and make returning the ball more difficult.”

“A lot of people have complained about grunting in the tennis world, that it’s distracting, and even some professionals have said it’s pretty much cheating,” said Sinnett, who conducted the research as a post-doctoral fellow at the University of British Columbia, and is now an assistant professor of psychology at the University of Hawai‘i at Mānoa.

“The study raises a number of interesting questions for tennis. For example, if Rafael Nadal is grunting and Roger Federer is not, is that fair?” he said in a statement.

Because grunting is so controversial in the sport of tennis, said Sinnett, who is a tennis player, he and the study co-authors was surprised to find that no one else had previously researched its impact with an empirical study.

Copyright © 2010 Deborah Jones

Originally published by Agence France-Presse, October 01, 2010