Some tennis players, especially on the women’s tour, are known for their grunting, which is easily heard when they play. Some people it’s a form of cheating, as it can be considered unsportsmanlike and distracting to opponents. But scientific studies have been performed to determine if grunting provides an advantage to the grunter or if it’s just annoying to some opponents and onlookers. Here’s what the data shows.

The science behind grunting in tennis

The Guardian helps us understand the science of grunting. Preliminary experimental work shows that grunting may mask important auditory information an opponent can use.

Participants watched videos of pro tennis players and had to quickly and accurately determine if the ball was hit to their right or left. The results showed that grunting did impair the speed and accuracy of the person’s decision-making. A delay of 30 milliseconds in responding with additional auditory stimulus present results in a typical rally shot is picked up about two feet later, compared to when there is no grunt.

This means opponents face more pressure as they have less time to prepare for the volley. Further evidence shows grunting enhances a player’s hitting velocity by 3.8% in groundstrokes.

Famous grunters in tennis

Some tennis players are more known for their grunting than others. Let’s take a look at some of the most famous grunting in tennis.

Monica Seles

Many consider the former women’s No. 1 one of the creators of the “art” of grunting. She’s been known to reach 90 decibels when she’s on the court. Seles discussed her grunting, reports Tennis 365, admitting that some people loved it while others hated it. She said she grunted since she was a girl as she put everything into each hit using big rackets. She says she grunted throughout her tennis development before the pros.

Maria Sharapova

Maria Sharapova took grunting to the next level. When asked about it, she said, “Either you do it, or you don’t. But you shouldn’t think about it.” Announcers dubbed one of Sharapova’s 2013 Wimbledon matches “the battle of the grunters,” when she took on Portuguese qualifier, Michelle Larcher de Brito. Sharapova’s grunt reportedly reached 103 decibels, but Larcher de Brito beat her out, getting up to 109 decibels.

Is grunting in tennis cheating?

Professional tennis players voice different opinions about grunting. Legendary player Martina Navritilova went on record saying it is “cheating pure and simple,” reports The Telegraph. Her argument is that the noise can hamper the opponent’s ability to hear the ball hitting the racket — a key element of preparing to return a shot.

Roger Federer says he’s “OK with it to a certain level.” But if it gets to be too much or is used at important moments, “That becomes unsportsmanlike.”

Whether or not grunting is cheating, the science mentioned earlier suggests that it enhances the player’s performance. This is likely why the practice has become popular in tennis. When you compete with the top players in the sport, you need every advantage you can get. Regardless, it gives both tennis fans and players something to talk about.