Kickboxing-themed gym operator 9Round has opened its 500th location in Orlando, Florida, US.

The franchise-based business has expanded rapidly since its launch nine years ago and now has a presence in 11 countries and 40 US states.

9Round – founded by former middleweight kickboxing world champion Shannon “The Cannon” Hudson – offers members specialised kickboxing fitness training based on 30-minute, full body training sessions undertaken in circuit format.

The 9Round system consists of nine, three-minute stations of activities – including cardio, weight training, core exercises, plus kicks and punches on speed bags.

A real boxing bell rings to begin the workout, another to warn the station is ending and a third to signal the end. Members have a 30-second active break between rounds to recover.

There are no class times for the 30-minute sessions, but trainers are always on site to lead the workouts and routines change daily.

Hudson says that he plans to have 1,000 9Round gyms open by the end of 2018.

"The convenience factor of our 30-minute, no-class-time workout coupled with the empowerment many people derive from kickboxing makes the concept extremely appealing to the masses,” Hudson said.

“This unique fitness proposition along with our rapid growth, are two of the key differentiators that make us stand out from the competition."