Fifteen years ago, my backyard and my house were full of basketballs, different colors for different purposes, indoor and outdoor, but all the same Size 7, the regulation ball for men’s games. But suddenly, the ball changed in European women's basketball, and new, smaller balls joined my home collection, Size 6. Along with being smaller, the balls were lighter and felt different, but this didn’t stop me from playing basketball. The size difference, though, changed everything about the game: the physics behind the throw, passing, and dribbling.

In the fall of 1978, the first professional Women’s Professional Basketball League (WBL) was formed in the U.S, 20 years after the women’s Euroleague. From the beginning, the WBL used Size 6 balls, which are about one inch smaller and two ounces lighter than men’s basketballs with circumference 28.5 inches and weight of 20 ounces. The smaller basketball size was suggested by WBL player Karen Logan, reasoning that women’s hands are on average smaller than men’s and their upper body strength also differs. However, the suggested change was not based on any scientific evidence. For all three seasons of the WBL’s existence, women played with smaller balls. When the Women's National Basketball Association (WNBA) was formed in 1996, they also adopted the Size 6 ball.

Outside of the U.S, reservations about smaller balls for women remained until 2004, when the International Basketball Federation (FIBA) changed the rule on the basketball size for women, mandating a Size 6. With a smaller ball, they hoped the score accuracy would improve, which would make games more interesting and attractive. But what does basketball science have to say? 

The first studies to investigate the effect of smaller balls on women players’ performance were initiated when they were introduced in the WBL. Early studies detected slight changes in ball handling skills, such as traveling, double dribbling calls, passing, steals, and shot accuracy. Brenda G. Pitts, a PhD student at the University of Alabama at the time, explored the “effect of a smaller and lighter ball on skill performance of female basketball players” as part of her 1985 thesis. The skill test included diverse shot positions, passes, and dribbling. When women players were tested using smaller balls in comparison to the larger ones their skills improved. However, the skills test wasn’t performed during an actual game and is only an approximation of skills used when playing against opponents. Pitts also raised concerns in the NCAA News that the ball size was arbitrarily chosen.

“Changing the size of the field, the height of the rim, the weight of the puck, and the size of the ball brings less value to women’s sports.”

Since the international adoption of the Size 6 ball, researchers have been able to collect sufficient data from games played before and after the size change to check if there was improvement in scoring accuracy. Once study  compared over a thousand games in which women played with larger basketballs to games when smaller balls were used. The research showed no improvement in scoring. Researchers recorded an increase in successful free throws when women played with Size 6 basketballs, but only on adult level. The findings didn’t replicate with the data from players in cadet categories (girls aged 16 and younger). 

Smaller balls could also impact the prevalence of dunking in women's basketball, but the smaller ball size would need to be accompanied by a lower rim. Three decades ago Pitts led a research group that explored which basketball size and hoop rim height would enable average female basketball players to dunk successfully. Recently, an active WNBA basketball player, Elena Delle Donne, suggested that women should have the rim height lowered to ease the dunks and make games more attractive. However, not everyone agrees that dunks would make women’s basketball more exciting. One can make a case against dunking when examining the way Stephen Curry plays, arguably “the ultimate NBA highlight,” who rarely dunks but is wildly famous and beloved for his style of play. His long shot precision and ball handling skills attract numerous fans to games. 

So far only eight female players have dunked successfully in the WNBA. The first was Lisa Leslie in 2002. But the first recorded women’s dunk happened more than a decade before WNBA was formed on the college level basketball in 1984. The number of dunks is also higher in college basketball than in the WNBA. The ball size is not the only reason not many women dunk—women who play professional basketball hold less secure positions and receive lower salaries than their men counterparts and cannot afford to sustain injuries and sit out a season or two.

Other team sports also use different equipment for men’s and women’s leagues. Net height in women’s volleyball is lower than for men’s, for example. Recently, the manager for England’s Chelsea team has suggested reducing the goal size in women's soccer to bridge the “‘physical differences’ between women and their male counterparts.” Similar initiatives have been present in hockey where a lighter puck was proposed for women. On both occasions, women players were against the change. 

Changing the size of the field, the height of the rim, the weight of the puck, and the size of the ball brings less value to women’s sports. Women's basketball is not as popular as men’s, but the size of a ball probably won’t change this. This isn’t because women’s sports are less competitive and exciting, but because of systemic sexisim based on the gendered idea that sports are masculine pursuit. This leads to less money invested in promotion and marketing of women’s sport, which, in turn, impacts the media coverage. Only a different attitude toward sports figures who aren’t men and greater support for women’s sports would improve their popularity. 

Image credit: Women’s basketball game. “17V5659" by Durham Lords, February 6, 2018 (Flickr | CC BY-NC-SA 2.0)