Happy families! Kimora Lee Simmons chases ex-husband Russell on the beach... as his model girlfriend laughs along

In great shape: Hip hop mogul Russell Simmons shows off his impressive yoga moves while on holiday with girlfriend Hana Nitsche in St Barts in the French West Indies on Christmas Eve

The flexible Def Jam founder bent double into the sand, his chest flat against his legs in a display that would have been impressive in a man half his 55-years.

To make the feat even more remarkable his lithe young girlfriend, 26-year-old German model Hana Nitsche, hopped on his back triumphantly.

She stood with her arms outstretched as he laughed in the sand.

On his head: The 55-year-old is worth $500m

Limber up: Russell isn't one to spend his beach time sunbathing

Russell then bent over double, his head on the sand as he limbered up.

After his acrobatic moves, Russell , whose net worth is estimated at $500 million, was covered in sand and decided to clean himself off.

Grabbing hold of Hana, he ran into the ocean as she squealed with laughter.

Happy holidays! Russell scoops up his girlfriend Hana Nitsche and runs into the surf with her to wash off

What a joker: At 55 Russell is 30 years older than his lover, but regular exercise and a strict vegan lifestyle have kept him in great shape

The Germany's Next Top Model star wore a festive red bikini to show off her figure as she soaked up the sun with her boyfriend.

Rather unusually it wasn't just a romantic time for the couple - but also a family break.

Joining them on the beach was Russell's ex-wife Kimora Lee Simmons, and their daughters Ming and Aoki, and her son Kenzo Hounsou from her second marriage.

Seasonal cheer: Happy Russell certainly seems to be enjoying his Christmas vacation

Looking good: Hana found fame on Germany's Next Top Model

She stretched out in her patterned bikini before taking a dip with her daughters.

Ladies man Russell enjoys a friendly relationship with his ex-wife, who 14 years ago he wed on this same island when the model was then 23 years old.

The former couple have been enjoying relaxed meals together with their children.

The proud father-of-two tweeted one snap of Kimora and his two little girls posing at his home. 'wowowow... looking at these photos, i can't believe how fast my daughters are growing up,' he wrote. 

The ex: Kimora Lee Simmons takes a dip as she enjoys her family holiday

1. Cooling down: Kimora sips froma a water bottle as she splashes around with her daughters