TRT Holdings, the majority shareholder of Gold's Gym since 2004, has put the fitness brand up for sale in order to "focus on its core businesses".

Gold's Gym was first launched in 1965 and currently has more than 700 locations across six continents.

The sites are a mixture of group-owned clubs and franchised gyms.

"Over the years we have received significant inbound interest from potential owners looking to buy the most iconic brand in fitness," said TRT Holdings president Blake Rowling.

"Given the tremendous growth currently happening in the fitness industry, the stellar leadership team we have in place and the recent excitement surrounding the evolution of the Gold's Gym brand, that interest has spiked considerably.

"With TRT Holdings' increased focus on its Omni Hotels & Resorts, we feel that now is the right time to go to market."

According to Brandon Bean, Gold's Gym CEO, the change of ownership could signal the next stage of the company's progress.

"The popularity and growth of the Gold's Gym brand is at an all-time high, and we're excited to work with a new ownership group to continue this momentum across all our key business units, including our company-owned gyms, domestic and international franchising operations and global licensing programme," Bean said.

"In the last 24 months we've rolled out an entirely new Gold's Gym experience focused on broadening the brand's appeal, expanding our membership base and getting more people than ever engaged in our unique products and services."

TRT Holdings has retained Piper Jaffray & Co. to conduct the sales process.

Dallas, US-based TRT Holdings is diversified private holding company that owns Omni Hotels & Resorts and Gold's Gym, as well as numerous other public and private investments.