Gelber began her race for the global title at Haifa University's rhetoric club. The club, operated by the university's Dean of Students, includes a team of competitors and judges of an international level and is considered to be one of Israel's most successful clubs today.
On her way to the desirable title, Gelber was required to deliver fiery speeches on a variety of issues, including the situation in Pakistan, the right to undergo fertility treatments, animal rights and atomic energy.
Winning the global title was another achievement in a series of victories after Gelber won the European Debate Championship during the years 2003-2005.
But the road to the top was not easy.
"At the beginning, I was unable to deliver a speech for more than 20 consecutive seconds and I suffered from stage fright," the new champion revealed Sunday.
"The training and the hard work at the club were what turned me into a champion. In order to succeed in such a competition one does not only need discussion skills, but also comprehensive knowledge and familiarity with everything that is happening in the world today," she said.
Gelber's trainer, Uri Zakai, who founded the rhetoric club, explained that "the club simulates a parliament with a coalition and an opposition, while each side must reasonably justify its arguments."
'Netanyahu a gifted speaker'
"Studies at the club train the young students to integrate into the fields of management, law and politics. (Former Prime Minister) Benjamin Netanyahu, (former Foreign Minister) Abba Eban and (former President) Chaim Herzog were part of such clubs when they were young, and their rhetoric skills helped them in their political ways," Zakai said.
When asked which Israeli politician is a good debater, Gelber quickly answers that "without revealing my political views, Benjamin Netanyahu is a gifted speaker. He knows how to use information, he knows how to phrase arguments and he knows how to simplify complicated issues into a language that any person can understand."
"Another good debater is (Knesset member) Yossi Sarid, who I believe is one of the most witty people in Israeli politics," she added.
Gelber's list of unsuccessful debaters is topped by former Prime Minister Ehud Barak.
"Barak is unequivocally not a good debater. He speaks to the audience as if it was an audience of subordinates who have to listen to him, and therefore makes no effort to convince them," she explained.
"Shimon Peres, in my opinion, makes a classic mistake when he asks a rhetorical question like 'am I a loser?' during a speech. And the audience in fact answered 'yes.' My advice to any politician is: Never ask a rhetorical question while delivering a speech," Gelber added.
The world champion offered a number of tips for delivering a winning speech.
"You have to know who is the audience. For example, is it young or old. And you have to prepare for the speech in advance. The speaker should be ready and support himself with facts, data and examples," she said.
"Another emphasis is on style, which is divided between a verbal style - for example using humor - and a non-verbal style, which means body language."