“Beach volleyball was a sport that was developed in Hawaii and Southern California and on the beaches of Rio,” Ross said. “And you play, and it’s hot, and then you go and jump in the water.”

One-piece bathing suits won’t work, because the sand gets inside and chafes; in fact, the players say, the less material that can trap sand, the better. Ross and her partner Alix Klineman, who helped design their own uniforms, also said it’s important that the straps don’t restrict her movement or breathing.

“For us, this is what feels most comfortable,” Klineman said. “You’re not wearing more clothing in really hot weather; getting sand stuck in places is not fun. But I totally respect other people wanting to be more covered if that’s what makes them more comfortable.”

Beach volleyball matches also proceed in all kinds of weather, including the rain from the leading edge of Typhoon Nepartak that dampened the Skiokaze Park venue this week. In Beijing, the Olympic championship was played in a downpour.

“This,” said American Misty May-Treanor, who was soaking wet but with a gold medal to show for it, “is just another reason why we play in bathing suits.”

Some teams did wear leggings and long sleeves under their uniforms on the cooler nights in 2012, dismaying the London tabloids, but even then most opted for the traditional board shorts and bikinis.

Four years later, after the FIVB expanded Olympic qualifying in an attempt to spread the sport to new countries, the Egyptians played in long sleeves, a loose-fitting top, full-length pant legs and hijabs to cover their heads.

“I have worn the hijab for 10 years,” said Doaa Elghobashy, a member of the first beach volleyball team from her country to compete in the Olympics.

“It doesn’t keep me away from the things I love to do,” she said. “And beach volleyball is one of them.”