Fitness First, one of the world's largest health club operators, has changed its top management team after experiencing a difficult period of trading at both its UK and Australian businesses.

Effective immediately, chief executive Colin Waggett and chief financial officer Duncan Tatton-Brown will step down from their roles. They are to be replaced with turnaround specialist Chris Stone as CEO and Jan Kengelbach of BC Partners as interim CFO.

John Gamble will also leave the business following a five-year stint.

Andrew Newington has been appointed chair and has been tasked with overseeing the changes. Donald Featherstone of AlixPartners will work with Newington as chief restructuring officer.

The company has also made changes at the regional management level.

Kengelbach will act as interim managing director for the UK business, while the team at Fitness First's low-cost arm Klick will report to Martin Seibold.

In Australia, Pete Manuel - who joined the company in 2011 - will be supported by Chris Martin of AlixPartners who will become interim financial director.

In Germany, Stefan Tilk will be joined by Peter Neubacher of AlixPartners to strengthen the operations team.

There are no changes to the Asia management team or structure.

Commenting on the news, David Stalker, CEO of Fitness Industry Association (FIA) said:"Fitness First is a competitive business that has been hurt by the ongoing worldwide recession.

"It has endeavoured to react to the money conscious market by delivering its budget brand Klick Fitness but has been unable to rectify its debt maturity problem.

"We acknowledge the business decision by BC Partners to recruit a new leadership team and as long standing members of the FIA, look forward to working with the new Fitness First board to promote physical activity."