Tamás Aján has stepped aside as President of the International Weightlifting Federation (IWF) for 90 days, pending investigations into allegations of corruption.
Ursula Papandrea, the American who chairs the IWF Women's Commission and is President of USA Weightlifting, takes charge until April.
The Hungarian has been at the IWF since 1976, serving 24 years as general secretary and the past 20 as President.
Aján's fifth term as President was due to run until May next year, and at the age of 81 he said he would not stand again.
But he is standing aside temporarily, pending investigations of claims made in a television documentary broadcast on January 5.
The decision was taken during a 13-hour meeting of the IWF Executive Board in Doha in Qatar.
The meeting was called in the aftermath of a recently aired German television documentary Secret Doping – Lord of the Lifters, which featured allegations of corruption, both financial and in anti-doping procedures.
The allegations were strongly denied by the IWF, and Aján claimed the documentary had "ruined my life and 50 years of my work".
In a statement released after the meeting, the IWF said it would now convene a group of independent experts "to assess the validity of the allegations" during the next 90 days.
Papandrea will head an Oversight and Integrity Commission "whose responsibilities will include identifying, nominating and recommending independent experts in fields including anti-doping and financial reporting", said the statement.
Joining Papandrea on the Commission will be fellow UWF Executve Board members from Oceania, Asia and Europe: Marcus Stephen from Nauru, Birendra Prasad Baishya from India and Karoliina Lundahl from Finland.
The new Commission will report to the Executive Board and the IWF Congress, scheduled for Bucharest on March 11 until 13.
In the statement, Aján claimed the German documentary's "allegations against the IWF in general and against me in particular are unfounded.
"They are not supported by the relevant documentation or by people involved in the relevant decisions.
"Consequently, I have no doubt that external experts will vindicate my commitment of nearly 50 years to develop the sport of weightlifting."
For the 90-day period and "consistent with the practice of good governance" Aján has "delegated a range of operational responsibilities" to Acting President Papandrea.
"Weightlifting has always been bigger than one man, and I am happy to have Ursula acting by my side in a Presidential capacity," he said.
Aján had earlier complained that the allegations related to the past, and that the documentary makers from Germany's state broadcaster ARD ignored recent reforms by the IWF, which had helped weightlifting regain permanent status on the Olympic Games schedule.
The International Olympic Committee (IOC) continued to monitor developments in the sport after officially confirming that status last May, and described as "very serious and worrying" the allegations in the documentary.
Aján, though, is confident the claims in the documentary will be dismissed.
"For me, the allegations made against the IWF and made against my person do not have substance," he said.
"I give you one example.
"The ARD claimed that millions of IOC TV revenue is missing from the Federation.
"But already today it was shown that no money is missing.
"Money from the IWF reserve accounts in Switzerland was moved to the IWF accounts in Hungary, to compensate for the operating shortfalls.
"These were not secrets.
"I was never the only signatory.
"The [IWF] Executive Board always knew where was the money. Internal auditors from the time have confirmed this.
"And external auditors found no irregularities.
"I have no doubt that independent experts will validate my position and the IWF position.
"It is worth it to wait a little longer to have this validation, in a way that is compatible with the best governance."