US-based health club chain 24 Hour Fitness, which has more than three million members worldwide, has been acquired by Forstmann Little, a New York City private investment firm, in a deal worth US$1.6bn (£840m, 1.2bn euros).

24 Hour Fitness’s chair and CEO, Mark Mastrov, who founded the company in 1983, will retain a ‘significant’ stake in the company and continue to run it with his existing management team.

Forstmann Little is financing the transaction with more than US$900m (£470m, 695m euros) from its equity and subordinated debt funds with the balance through a senior loan facility.

“24 Hour Fitness has a very strong market position, a superb management team and significant potential for growth,” said Ted Forstmann, senior partner at Forstmann Little.

24 Hour Fitness currently has 330 health clubs in the US and a further 15 in Asia. It plans to accelerate growth in both markets with Forstmann Little’s backing. Details: www.24hourfitness.com