Chess chiefs ask why it's still mostly a man's game. Culture, but hormones and endurance too?

GENEVA (AP) — A top global chess official on Friday called for more research into whether factors such as hormone levels and physical endurance might have an impact on players' abilities at the game, which has traditionally been and remains dominated by men.

The world chess federation FIDE stirred controversy with its decision, announced this week and set to take effect Monday, to prohibit transgender women from its official events for women until the federation makes an assessment of the issue.

Dana Reizniece-Ozola, the deputy chair of the federation's management board, insisted that the goal of the new regulations was “actually to increase the rights of the transgender persons and allow them being registered under their new gender” in its official directory.

Tournaments only for women were created in the 1970s as a way to foster their participation in a sport that has long been dominated by men. Even now only 2% of all players — and 10% of rated players — are women, she said.

The new regulations, which could subject transgender women to a waiting period of up to two years as the issue is examined, was aimed at giving FIDE a “grace period” to sort out the matter of transgender players and men's dominance in the sport.

“What is still not clear is if the hormonal levels do influence the competitiveness in chess," she said by video from Latvia's capital, Riga. "There is no serious research or scientific analysis that would prove one or the other way. There are speculations, but no more than that.”

Many sports involving intense physical activity — which chess does not — have been grappling with how to formulate policies toward transgender athletes in recent years.

Cathy Renna, communications director for the U.S. National LGBTQ Task Force, said the new rules appeared to be “a case of ‘trans panic’ with no justification, not grounded in reality and once again marginalizing trans people.”

Reizniece-Ozola said FIDE, like other sports organizations, needs to balance equality — providing rights to every person to compete on an equal basis — and fair competition. “This is the aspect that really needs more and more research, scientifically based research," she said.

“Even though it’s not the physical sports, you need some endurance working on the chess game for four or sometimes four or five and more hours in a longer period of time," Reizniece-Ozola said.

Culture, she said, was “probably” the main reason that women were less active in chess “because chess has not been regarded as a sport that is appropriate for women in so many cultures. So that ... has created this huge gender gap.”

The foundation of chess, which she called an “intellectual sport,” is equal: "I mean, there is no difference between men and women at the intellectual part. But still, we see that the statistical data show the differences between men and women.”

Word of the decision came as the federation is hosting a World Cup event in Azerbaijan where top players, including No. 1-ranked Grand Master Magnus Carlsen of Norway, are attending.

The federation has open competitions that allow all players to take part, as well as specialized categories, such as for young players and even computers.