Uganda's parliament has opened a probe into the alleged sex abuse of elite female runners from the national team by a top coach, calling the affair a "national shame".

The east African nation, an emerging distance running power that has been trying to take on regional rivals Kenya and Ethiopia, has been gripped by the scandal for nearly a month.

According to officials and local media reports, female runners were subjected to sexual harassment and abuse while participating in a training camp to prepare for last month's Africa Cross-country Championships.

"This is a national shame that a coach can harass these young girls and he goes scot-free," Betty Amongi, an MP and chair of Uganda parliamentary women's association, told reporters.

"We are opening investigations as parliament so that the culprit is arrested and punished for sexual harassment of the female athletes," she added.

The scandal broke after Moses Kipsiro, a Commonwealth double gold medallist and one of Uganda's top distance runners, went public and relayed complaints from his female teammates.

He said the accused coach, who cannot be named for legal reasons, told some of the women runners that they had to have sex in order to perform better on the grounds that "if a woman's private parts are wide, their legs move easily."

The Uganda Athletics Federation (UAF) has also been accused of inaction and even dropping Kipsiro from the national squad for the World Half Marathon Championships as punishment for speaking out.

According to Amongi, police have also failed to take any action, even though several runners have filed formal complaints.

"We want the athletes to come out and expose these culprits," the MP said, adding that police and the government "must protect the victims and the whistleblowers in this case."

Ugandan police spokesman Fred Enanga confirmed a criminal investigation was now underway.

"We are taking up the matter. Those with information should pass it on to us to enable investigations," he told AFP.